Apramycin derivatives

Abstract

The invention relates to derivatives of apramycin-based aminoglycoside antibacterial drugs modified in positions C5 and/or C6 and O5 and/or O6. The modifications impart favourable properties regarding increased selectivity and retention of activity in the presence of resistance determinants of the AAC(3) class. The invention further relates to said compounds for use in the therapy of bacterial infection by systemic administration, especially in instances where the infection is caused by a pathogen comprising a resistance determinant of the AAC(3) class, in particular AAC(3)-IV.

Claims

1. A compound characterized by a general formula (100) ##STR00012## wherein E is selected from H and (S)-4-amino-2-hydroxybutyryl, (S)-3-amino-2-hydroxypropionyl, —CON(OH)(CH.sub.2).sub.2NH.sub.2, (2R,4S)-2-hydroxy-4,5-diamino-pentanoyl, and (2S,4R)-2,5-dihydroxy-4-aminopentanoyl; V is selected from H and CH.sub.2-D, wherein D is selected from OH, NH.sub.2, NHCHO, NHR.sup.D and NHCONHR.sup.D, wherein R.sup.D is selected from H, OH, unsubstituted or amino- and/or hydroxy-substituted C.sub.1 to C.sub.6 alkyl; U and W are selected from the following alternatives: one of U and W is —R.sup.W and the other one is selected from H, F and OH, or one of U and W is —OR.sup.W and the other one is H, wherein R.sup.W is selected from an amino- and/or hydroxy-substituted C.sub.1 to C.sub.6 alkyl, CH.sub.2(CH.sub.2).sub.nNH(CH.sub.2).sub.3NH.sub.2 and CH.sub.2(CH.sub.2).sub.n—R.sup.N, wherein n is selected from 1, 2 or 3, R.sup.N is selected from NXY and a moiety characterized by formula (400) ##STR00013## wherein X and Y are independently selected from H, and unsubstituted or amino- and/or hydroxyl-substituted C.sub.1 to C.sub.3 alkyl, and Z is selected from O, NX and CH.sub.2, or one of U and W is described by a moiety characterized by formula (300), (301), (304) or (305) and the other one of U and W is H ##STR00014## wherein R″ is selected from H and an amino- and/or hydroxy-substituted C.sub.1 to C.sub.6 alkyl.

2. The compound according to claim 1, wherein V is selected from CH.sub.2OH, H, CH.sub.2NHCHO and CH.sub.2NHCONH.sub.2.

3. The compound according to claim 1, wherein V is CH.sub.2NHR.sup.D.

4. The compound according to claim 1, wherein E is H.

5. The compound according to claim 1, wherein one of U and W is —R.sup.W and the other one is selected from H, F, OH, or one of U and W is —OR.sup.W and the other one is H.

6. The compound according to claim 1, wherein R.sup.W is selected from (CH.sub.2).sub.2OH, (CH.sub.2).sub.2NH.sub.2, (CH.sub.2).sub.2NMe.sub.2, (CH.sub.2).sub.2NEt.sub.2, (CH.sub.2).sub.2NHMe, (CH.sub.2).sub.2NHEt, (CH.sub.2).sub.3OH, (CH.sub.2).sub.3NH.sub.2, (CH.sub.2).sub.3NMe.sub.2, (CH.sub.2).sub.3NEt.sub.2, (CH.sub.2).sub.3NHMe, (CH.sub.2).sub.3NHEt, CH.sub.2CHOHCH.sub.2OH, CH.sub.2CHOHCH.sub.2NH.sub.2, CH.sub.2CHOHCH.sub.2NMe.sub.2, CH.sub.2CHOHCH.sub.2NEt.sub.2, CH.sub.2CHOHCH.sub.2NHMe and CH.sub.2CHOHCH.sub.2NHEt.

7. The compound according to claim 1, wherein a. W is —R.sup.W and U is selected from H, F, OH, or b. W is —OR.sup.W and U is H.

8. The compound according to claim 1, characterized by a general formula (112), (113) or (114) ##STR00015## wherein R.sup.AP designates a moiety described by formula (2) ##STR00016## and denotes the position where the apramycin backbone is attached to the compound described by general formula (112), (113), or (114), wherein U is selected from OH and F and n, R″, R.sup.N and V have the same meaning as indicated above.

9. The compound according to claim 8, characterized by the general formula a.(112), E is H, R.sup.N is OH, Vis CH.sub.2OH and n is 1 [5—O-β-[3″′-O-(2-hydroxyethyl)-D-ribofuranosyl] apramycin; DCWSU178]; b. (112), E is H, R.sup.N is NH.sub.2, V is CH.sub.2NH.sub.2 and n is 1 [5—O-β-[5-amino-3-O-(2-aminoethyl)-5-deoxy-D-ribofuranosyl] apramycin; DCWSU185]; c.(112), wherein E is H, V is CH.sub.2NHCOH, R.sup.N is NH.sub.2 and n is 1 [5—O-β-[3-O-(2-aminoethyl)-5-deoxy-5-formamido-D-ribofuranosyl] apramycin; DCWSU186].

10. The compound according to claim 1, wherein a. E, U and V are H and W is —OR.sup.W, and R.sup.W is selected from (CH.sub.2).sub.2OH, (CH.sub.2).sub.2NH.sub.2, (CH.sub.2).sub.2NMe.sub.2, (CH.sub.2).sub.2NEt.sub.2, (CH.sub.2).sub.2NHMe, (CH.sub.2).sub.2NHEt, (CH.sub.2).sub.3OH, (CH.sub.2).sub.3NH.sub.2, (CH.sub.2).sub.3NMe.sub.2, (CH.sub.2).sub.3NEt.sub.2, (CH.sub.2).sub.3NHMe, (CH.sub.2).sub.3NHEt, CH.sub.2CHOHCH.sub.2OH, CH.sub.2CHOHCH.sub.2NH.sub.2, CH.sub.2CHOHCH.sub.2NMe.sub.2, CH.sub.2CHOHCH.sub.2NEt.sub.2, CH.sub.2CHOHCH.sub.2NHMe and CH.sub.2CHOHCH.sub.2NHEt; or b. E and U are H, V is CH.sub.2OH and W is a moiety described by formula (300), with R″ selected from H, (CH.sub.2).sub.2OH, (CH.sub.2).sub.2NH.sub.2, (CH.sub.2).sub.2NMe.sub.2, (CH.sub.2).sub.2NEt.sub.2, (CH.sub.2).sub.2NHMe and (CH.sub.2).sub.3NHEt.

11. The compound according to claim 1, wherein D is selected from OH, NHCHO and NHCONH.sub.2.

12. The compound according to claim 1, wherein X and Y are independently selected from H, CH.sub.3, CH.sub.2CH.sub.3, CH.sub.2CH.sub.2OH or CH.sub.2CH.sub.2NH.sub.2.

13. The compound according to claim 1, wherein one of U and W is ##STR00017##

14. A method for treatment of a bacterial infection comprising: systemically administering to a subject in need thereof the compound of claim 1, wherein the infection is caused by a pathogen from family Enterobacteriaceae, thereby treating the bacterial infection.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIGS. 1 to 11 show the synthesis of exemplary compounds of the invention that are ribosylated at position 5.

(2) FIGS. 12 to 14 show the synthesis of exemplary compounds of the invention that are modified at position 5.

(3) FIG. 15 shows the synthesis of exemplary compounds of the invention that are modified at position 5 and at position 1-N.

(4) FIG. 16 shows the synthesis of exemplary compounds of the invention that are modified at position 6.

(5) FIG. 17 shows the synthesis of key intermediate compound 5-OH apramycin.

EXAMPLES

Example 1

General Methods and Materials

(6) All reagents and solvents were purchased from commercial suppliers and were used without further purification unless otherwise specified. Chromatographic purifications were carried out over silica gel. Analytical thin-layer chromatography was performed with pre-coated glass backed plates (w/UV 254) and visualized by UV irradiation (254 nm) or by staining with 25% H.sub.2SO.sub.4 in EtOH or ceric ammonium molybdate (ceric sulfate: (4.0 g); ammonium molybdate (10 g); H.sub.2SO.sub.4: 40 mL, H.sub.2O: 360 mL) solution. Specific rotations were obtained using a digital polarimeter in the solvent specified at 589 nm and 23° C. on an Autopol III polarimeter (Rudolph Research Analytical, Hackettstown, N.J.) with a path length of 10 cm. Infrared spectra were recorded on a FT/IR instrument. High resolution mass spectra were recorded with an electrospray source coupled to a time-of-flight mass analyzer (Waters). .sup.1H, .sup.13C and 2D NMR spectra were recorded on 400 MHz, 500 MHz or 600 MHz instruments as specified. Assignments in .sup.1H and .sup.13C NMR were done by the assistance of H—H COSY, HSQC and/or HMBC experiments.

(7) Chemistry: All syntheses were run under an atmosphere of nitrogen or argon. Solvents were dried and purified by standard techniques.

(8) Minimal inhibitory concentrations (MIC) have been determined by broth microdilution assays (CLSI. Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically; Approved Standard—Tenth Edition. CLSI document M07-A10. Wayne, Pa.: Clinical and Laboratory Standards Institute; 2015.).

(9) IC50 values for bacterial, human chimeric, and rabbit reticulocyte ribosomes have been determined by in-vitro translation assays as described previously (Proc. Nat. Ac. Sci USA 2012, 109(27):10984-10989).

Example 2

(10) Apramycin Derivatives Active in the Presence of AAC(3) AMEs.

(11) A) O5-ribosylated apramycin derivatives

(12) Table 1 shows 5-ribosylated apramycin derivatives. Minimal inhibitory concentrations (MICs, pg/ml) against clinical isolates from Institute of Medical Microbiology, Univ. Zurich, and the IC50 values for bacterial, human mitochondrial and human cytosolic ribosomes are indicated.

(13) Compounds 124 and 138, in which the β-D-ri bofuranosyl ring appended to the O5-position of apramycin is substituted with a basic residue at the 3′″-position show excellent antiribosomal and antibacterial activity even against the IMM clinical isolates carrying the gene for AAC(3)-IV. These compounds are distinct from the simple unsubstituted β-D-ribofuranosyl apramycin derivative (compound 131), which was described in 1981 by a Japanese group, and which shows no activity against the AAC(3)-IV carrying bacterial strains.

(14) The introduction of a ribofuranosyl ring renders compound 124 and compound 138 susceptible to the APH(3′, 5″) resistance determinant, but modifications such as the inclusion of a 5″-formamido group as in compound 186 circumvent this problem. The introduction of a formamido group results in compounds that display increased selectivity for the bacterial ribosome over the mitochondrial (wild type and A1555G mutant) ribosomes, predictive of reduced ototoxicity.

(15) In addition to its outstanding antibacterial profile, compound 124 shows excellent selectivity at the target level with only low activity against eukaryotic ribosomes, indicating that it will share and even improve on the toxicity profile of apramycin itself.

(16) Compound 185 shows increased antibacterial potency not only against Enterobacteriaceae, but also and in particular for Pseudomonas, Acinetobacter, and Mycobacteria (Tables 4+5).

B) 5-OH Manipulated Apramycin Derivatives

(17) Table 2 shows 5-OH manipulated apramycin derivatives.

(18) Examples include the manipulation of the 5-OH of apramycin by deoxygenation (compound 169), inversion (compound 161), substitution by a halogen atom (compound 170 and compound 168) or by alkylation.

(19) Changes in the polarity or conformation of the substituent in position 5 (by oxygenation, inversion or substitution by a halogen atom) increase the antibacterial potency in comparison to the native apramycin. These compounds also circumvent the resistance mechanism apmA, a particular case in point being illustrated by compound 161.

(20) Alkylation is expected to provide a similar effect as the ribosylation described above.

(21) Minimal inhibitory concentrations (μg/ml) against clinical isolates from Institute of Medical Microbiology, Univ. Zurich, and the IC50 values for bacterial, human mitochondrial and human cytosolic ribosomes are indicated.

C) 6-OH Manipulated Apramycin Derivatives

(22) Table 3 shows apramycin derivatives in which the 6-OH of apramycin is manipulated by alkylation.

(23) Compound 167 shows an increased target specificity for bacterial versus human rRNA.

(24) The Minimal inhibitory concentrations (MICs, μg/ml) against clinical isolates from Institute of Medical Microbiology, Univ Zurich, and the IC50 values for bacterial, human mitochondrial and human cytosolic ribosomes are indicated.

(25) Table 4 and 5 show the antibacterial activity of the compounds of the invention against bacterial reference strains (table 4) and against representative clinical isolates (table 5).

(26) Table 6 shows the activity of the compounds of the invention against G1405-methylated 16S-rRNA.

Example 3

DCWSU123 and DCWSU124

(27) See the synthetic scheme of FIG. 1.

(28) 3-O-(2-Azidoethyl)-5-O-benzyl-1,2-O-isopropylidenea-α-D-ribofuranose (E). 5-O-Benzyl-1,2-O-isopropylidene-α-D-ribofuranose (1.00 g, 3.57 mmol) was dissolved in dry THF (3 mL) and NaH (214 mg, 5.36 mmol) was added under argon. After stirring for 15 min, a solution of 2-azidoethyl tosylate (1.72 g, 7.14 mmol) in dry THF (3 mL) was added dropwise followed by stirring for 12 h. More NaH (150 mg, 3.75 mmol) and 2-azidoethyl tosylate (860 mg, 3.57 mmol) were added and stirring continued for 24 h. After completion, the reaction was quenched with methanol and concentrated in vacuo and the crude product was purified by column chromatography (eluent: 5% to 30% EtOAc/hexanes) to give E (974 mg, 78%) as a gum; [α].sub.D.sup.25==+71.2 (c=1.0); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.37-7.26 (m, 5H, ArH), 5.81 (d, J=3.8 Hz, 1H, H-1), 4.67-4.61 (m, 2H, H-2, PhCH.sub.2), 4.55 (d, J=12.2 Hz, 1H, PhCH.sub.2), 4.12 (ddd, J=9.0, 3.7, 2.1 Hz, 1H, H-4), 3.89-3.84 (m, 2H, H-3, H-5), 3.81 (dd, J=11.5, 2.2 Hz, 1H, OCH.sub.2), 3.67-3.58 (m, 2H, OCH.sub.2, H-5), 3.45 (ddd, J=13.3, 7.4, 3.5 Hz, 1H, CH.sub.2N.sub.3), 3.28 (ddd, J=13.3, 5.6, 3.5 Hz, 1H, CH.sub.2N.sub.3), 1.57 (s, 3H, CH.sub.3), 1.35 (s, 3H, CH.sub.3); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 137.99 (Ar—C), 128.37 (Ar—C), 127.78 (Ar—C), 127.68 (Ar—C), 112.98 (CMe.sub.2), 104.13 (C-1), 78.61 (C-2), 77.89 (C-3), 77.17 (C-4), 73.52 (PhCH.sub.2), 69.38 (C-5), 67.65 (OCH.sub.2), 50.59 (CH.sub.2N.sub.3), 26.69 (CH.sub.3), 26.58 (CH.sub.3); ESI-HRMS: m/z calcd for C.sub.17H.sub.23N.sub.3O.sub.5Na [M+Na].sup.+ 372.1535, found 372.1533

(29) 3-O-(2-Azidoethyl)-5-O-benzyl-1,2-di-O-(4-nitrobenzoyl)-α-D-ribofuranose (F). A solution of E (822 mg, 2.36 mmol) in a 1:3 mixture of 1 N aqueous hydrochloric acid and p-dioxane (16 mL) was stirred for 1.5 h at ambient temperature then was concentrated and dried under reduce pressure. The residue was diluted with pyridine (40 mL) and treated with 4-dimethylaminopyridine (30 mg, 0.236 mmol) and p-nitrobenzoyl chloride (1.53 g, 8.26 mmol) at ambient temperature and stirred for 10 h. The reaction mixture was concentrated and the residue was purified by silica gel column chromatography (hexane: ethyl acetate 8:1 to 4:1). to give F as a white foam (643 mg, 1.06 mmol, 45%); [α].sub.D.sup.25 =+66.9 (c=1.0); .sup.1H NMR (600 MHz, CDCl.sub.3) δ32 8.26 (s, 4H, ArH); 8.20 (d, J=8.8 Hz, ArH); 8.12 (d, J=8.8 Hz, ArH); 7.39-7.26 (m, 5H, ArH); 6.80 (d, J=4.4 Hz, 1H, H-1); 5.45 (dd, J=4.4 Hz, 6.6 Hz, 1H, H-2); 4.65 (d, J=11.7 Hz, 1H, PhCH); 4.58 (d, J=11.7 Hz, 1H, PhCH.sub.2); 4.58 (m, 1H, H-4); 3.86 (dd, J=6.6 Hz, 2.9 Hz, 1H, H-3); 3.74-3.65 (m, 4H, H-5, CH.sub.2CH.sub.2N.sub.3); 3.33 (m, 1H, CH.sub.2CH.sub.2N.sub.3); 3.28 (m, 1H, CH.sub.2CH.sub.2N.sub.3); .sup.13C NMR (150 MHz, CDCl.sub.3) δ=163.72, 163.56, 150.84, 150.79, 137.47, 131.00, 130.80, 128.55, 127.96, 127.70, 123.65 (18C, ArC.); 95.82 (C-1); 84.70 (C-4); 76.91 (C-3); 73.73 (PhCH.sub.2); 73.14 (C-2); 70.33 (—CH.sub.2CH.sub.2N.sub.3); 69.38 (C-5); 51.12 (CH.sub.2CH.sub.2N.sub.3); ESI-HRMS: m/z calcd for C.sub.28H.sub.25N.sub.5O.sub.11Na [M+Na].sup.+ 630.1448, found 630.1453.

(30) 5-O-α-[3′″-O-(2-Azidoethyl)-5′″-O-benzyl-2′″-O-(4-nitrobenzoyl)-D-ribofuranosyl]-6,2″, 3″, 6″-tetra-O-acetyl-1,3,2′, 4″-tetraazido-6′, 7′-oxazolidino-apramycin (Gα) and 5-O-β-[3′″-O-(2-Azidoethyl)-5′″-O-benzyl-2′″-O-(4-nitrobenzoyl)-D-ribofuranosyl]-6,2″, 3″, 6″-tetra-O-acetyl-1,3,2′, 4″-tetraazido-6′, 7′-oxazolidino-apramycin (Gβ) 3-O-(2-Azidoethyl)-5-O-benzyl-1,2-di-O-(4-nitrobenzoyl)-α-D-ribofuranose F (181 mg, 0.30 mmol) and apramycin derivative A (100 mg, 0.12 mmol) were charged to a round bottom flask, co-evaporated with toluene three times and dried in vacuo overnight. The flask was purged with argon and the mixture dissolved in dry DCM (1.5 mL) before cooling to 0° C., treatment with BF.sub.3.OEt.sub.2 (0.23 mL, 0.63 mmol) and stirring for 12 h. The reaction was quenched with triethylamine (0.2 mL), diluted with EtOAc and washed with aqueous NaHCO.sub.3 and brine then concentrated. The crude product was purified using silica gel column chromatography (eluent: 20%-40% EtOAc/hexanes) to give Gα (35 mg, 23%) and Gβ (31 mg, 20%); α anomer: [α].sub.D.sup.25=+79.1 (c 1.1, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 8.32 (d, J=8.6 Hz, 2H, ArH), 8.23 (d, J=8.9 Hz, 2H, ArH), 7.36-7.29 (m, 5H, ArH), 5.68-5.65 (m, 1H, H-2′″), 5.56 (d, J=3.8 Hz, 1H, H-1′″), 5.38 (t, J=10.0 Hz, 1H, H-3″), 5.32 (d, J=3.8 Hz, 1H, H-1″), 5.15 (d, J=3.5 Hz, 1H, H-1), 4.94-4.87 (m, 3H, H-2″, H-6, H-8), 4.75 (dd, J=8.4, 3.1 Hz, 1H, H-6), 4.66 (dd, J=10.5, 3.1 Hz, 1H, H-5), 4.60 (d, J=11.9 Hz, 1H, CH.sub.2Ph), 4.54 (d, J=12.0 Hz, 1H, CH.sub.2Ph), 4.31 (dd, J=12.1, 1.8 Hz, 1H, H-6″), 4.25 (dt, J=7.0, 3.3 Hz, 1H, H-4′”), 4.21 (dd, J=12.2, 5.2 Hz, 1H, H-6″), 4.04 (dd, J=7.6, 5.1 Hz, 1H, H-3′″), 3.79 (dd, J=8.4, 3.0 Hz, 1H, H-7), 3.75-3.69 (m, 4H, H-4′, H-5, H-5′, H-5″), 3.68-3.62 (m, 1H, H-3), 3.62-3.57 (m, 3H, H-5′″, H-4′, OCH.sub.2CH.sub.2), 3.56-3.48 (m, 3H, H-1, H-4, OCH.sub.2CH.sub.2), 3.29 (dt, J=12.8, 4.1 Hz, 1H, H-2′), 3.18 (t, J=4.9 Hz, 2H, OCH.sub.2CH.sub.2), 2.91 (s, 3H, NCH.sub.3), 2.42 (dt, J=12.9, 4.4 Hz, 1H, H-2), 2.25 (dt, J=10.6, 4.3 Hz, 1H, H-3), 2.13 (s, 3H, COCH.sub.3), 2.11 (s, 3H, COCH.sub.3), 2.09 (m, 6H, COCH.sub.3), 1.86 (q, J=11.5 Hz, 1H, H-3′), 1.55 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.3 (C═O), 169.9 (C═O), 169.8 (C═O), 164.3 (C═O), 156.9 (C═O), 150.9 (Ar—C), 137.5 (Ar—C), 134.6 (Ar—C), 131.1 (Ar—C), 128.5 (Ar—C), 127.9 (Ar—C), 127.8 (Ar—C), 123.8 (Ar—C), 102.8 (C-1′″), 97.8 (C-1), 95.0 (C-8), 94.2 (C-1″), 82.5 (C-5), 80.4 (C-4″), 80.1 (C-4), 77.2 (C-3′″), 73.6 (C-6), 73.6 (CH.sub.2Ph), 71.3 (C-2′″), 70.7 (C-3′), 70.0 (C-2″), 69.9 (C-6), 69.9 (OCH.sub.2CH.sub.2), 68.9 (C-5′″), 68.7 (C-5″), 65.5 (C-5′), 65.2 (C-4′), 62.8 (C-6″), 60.2 (C-7′), 60.1 (C-4″), 58.3 (C-3), 58.1 (C-1), 56.7 (C-2′), 50.6 (OCH.sub.2CH.sub.2), 31.4 (C-2′), 30.3 (C-3), 29.8 (NCH.sub.3), 21.2 (COCH.sub.3), 20.8 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.51H.sub.59N.sub.17O.sub.23 [M+Na].sup.+ 1300.3867; found, 1300.3887; β anomer: [α].sub.D.sup.25=+70.8 (c 1.8, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 8.28 (d, J=8.6 Hz, 2H, ArH), 8.20 (d, J=8.7 Hz, 2H, ArH), 7.46-7.26 (m, 5H, ArH), 5.79 (d, J=3.4 Hz, 1H, H-1), 5.42 (t, J=10.0 Hz, 1H, H-3′″), 5.38 (s, 1H, H-1′″), 5.37 (d, J=3.8 Hz, 1H, H-1″), 5.23 (d, J=4.2 Hz, 1H, H-2′″), 4.92 (t, J=9.7 Hz, 1H, H-6), 4.86 (dd, J=10.3, 3.8 Hz, 1H, H-2″), 4.81 (d, J=4.4 Hz, 1H, H-8′), 4.76 (dd, J=7.5, 3.2 Hz, 1H, H-6′), 4.60 (d, J=11.9 Hz, 1H, CH.sub.2Ph), 4.51 (d, J=11.9 Hz, 1H, CH.sub.2Ph), 4.39 (dd, J=10.3, 3.2 Hz, 1H, H-5′), 4.33 (d, J=12.0 Hz, 1H, H-6″), 4.26-4.16 (m, 2H, H-6″, H-4′″), 4.14 (dd, J=7.1, 4.5 Hz, 1H, H-3′″), 3.84-3.71 (m, 3H, H-5, H-7′, H-5″), 3.71-3.52 (m, 8H, H-4, H-4′, H-4″, H-3, H-5′″, OCH.sub.2CH.sub.2), 3.47-3.37 (m, 1H, H-1), 3.17 (m, 2H, OCH.sub.2CH.sub.2), 3.09 (dt, J=12.8, 3.9 Hz, 1H, H-2′), 2.94 (s, 3H, NHCH.sub.3), 2.41 (dt, J=12.9, 4.3 Hz, 1H, H-2), 2.19-1.99 (m, 13H, 4COCH.sub.3, H-3′), 1.88 (q, J=11.8 Hz, 1H, H-3′), 1.57 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.4(C═O), 170.1(C═O), 169.8 (C═O), 169.7 (C═O), 163.8 (C═O), 157.1 (C═O), 150.8 (Ar—C), 137.7 (Ar—C), 134.5 (Ar—C), 131.1 (Ar—C), 130.9 (Ar—C), 128.5 (Ar—C), 127.8 (Ar—C), 127.7 (Ar—C), 123.7 (Ar—C), 123.6 (Ar—C), 106.9 (C-1′”), 97.3 (C-1), 96.4 (C-8′), 94.2 (C-1″), 82.0 (C-5), 80.5 (C-4′″), 77.8 (C-4), 76.8 (C-3′″), 75.7 (C-6), 75.0 (CH.sub.2Ph), 73.4 (C-2′″), 71.0 (C-3″), 70.4 (C-2″), 70.2 (C-6′), 70.0 (OCH.sub.2CH.sub.2), 69.7 (C-5′″), 69.1 (C-5″), 65.9 (C-5′), 65.7 (C-4′), 62.9 (C-6″), 60.2 (C-7′), 60.1 (C-4″), 59.1 (C-3), 58.1 (C-1), 56.5 (C-2″), 50.6 (OCH.sub.2CH.sub.2), 31.3 (C-2), 30.1 (C-3′), 29.7(NCH.sub.3), 20.9 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3), 20.7 (COCH3); ESI-HRMS: m/z calcd. for C.sub.51H.sub.59N.sub.17O.sub.23 [M+Na].sup.+ 1300.3867; found, 1300.3835.

(31) 5-O-α-[3-O-(2-Aminoethyl)-D-ribofuranosyl] apramycin hexaacetate salt (DCWSU123). A stirred solution of compound Gα (30 mg, 0.02 mmol) in dioxane (0.5 mL) was treated with 3N NaOH (0.25 mL) and heated at 100° C. for 18 h. The reaction mixture was cooled to rt and neutralized with glacial acetic acid and concentrated in vacuo. The crude product was passed through a silica gel column (eluent: 50% methanol/DCM). The product-containing fractions was concentrated and dissolved in THF (0.6 mL) followed by the addition of 0.3N NaOH (0.3 mL) and 1M P(CH.sub.3).sub.3 in THF (0.3 mL). The reaction mixture was stirred at 55° C. for 2 h then concentrated and purified by column chromatography (eluent: 5% to 50% ammonia/MeOH).

(32) The product-containing fractions were concentrated, dissolved in dioxane:water:glacial acetic acid=1:2:0.2 (0.3 mL). Pd(OH).sub.2/C (0.5 equiv) was added and the reaction mixture was stirred at room temperature under 1 atm of hydrogen (balloon) for 4 h. After completion, the reaction mixture was filtered over Celite®, concentrated to dryness and dissolved in aqueous acetic acid solution (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then eluted with a gradient of 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid and lyophilized to afford DCWSU123 (21 mg, 85%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+52.3 (c 1.1, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.65 (d, J=3.4 Hz, 1H, H-1′), 5.33 (s, 1H, H-1″), 5.24 (d, J=4.4 Hz, 1H, H-1′″), 5.03 (d, J=8.4 Hz, 1H, H-8′), 4.40 (s, 1H, H-6′), 4.23-4.18 (m, 1H, H-2′″), 4.16 (q, J=3.6 Hz, 1H, H-4′″), 3.87-3.80 (m, 1H, H-4), 3.80-3.64 (m, 8H, H-3″, H-4′, H-5, H-5″, H-3′″, H-6″, OCH.sub.2CH.sub.2), 3.64-3.41 (m, 7H, H-6″, H-5′, H-6, H-5′″, H-2′, H-5′, H-2′″), 3.29-3.11 (m, 3H, H-1, H-3, H-7′), 3.05 (m, 3H, OCH.sub.2CH.sub.2, H-4″), 2.60 (s, 3H, NCH.sub.3), 2.29-2.16 (m, 2H, H-2, H-3′), 1.91-1.80 (m, 1H, H-3′), 1.66-1.56 (m, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 102.8 (C-1′″), 95.1 (C-1′), 94.4 (C-1″), 92.9 (C-8″), 84.3 (C-5), 83.2 (C-4′″), 78.4 (C-4), 78.0 (C-3′″), 71.6 (C-6), 70.9 (C-2′″), 70.3 (C-5″), 69.8 (C-2″), 68.7 (C-4′), 66.8 (OCH.sub.2CH.sub.2), 66.0 (C-5′), 62.8 (C-6′), 61.5 (C-5′″), 60.3 (C-6″), 59.5 (C-7′), 52.0 (C-4″), 50.0 (C-3), 48.6 (C-1′), 47.8 (C-2′), 39.1 (OCH.sub.2CH.sub.2), 30.1 (NCH.sub.3), 29.2 (C-2), 27.0 (C-3′); ESI-HRMS: m/z calcd. for C.sub.28H.sub.55N.sub.6O.sub.15 [M+H].sup.+ 715.3725; found, 715.3742.

(33) 5-O-β-(3′″-O-(2-Aminoethyl)-D-ribofuranosyl) apramycin hexaacetate salt (DCWSU124). Substrate Gβ (35 mg, 0.03 mmol) was deprotected in the same manner as compound Gα to yield DCWSU124 (30 mg, 95%) as a pentaacetate salt in the form of a white solid; [α].sub.D.sup.25=68.92 (c 0.5, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.64 (d, J=3.6 Hz, 1H, H-1′), 5.28 (d, J=3.7 Hz, 1H, H-1″), 5.16 (s, 1H, H-1′″), 5.00 (d, J=8.5 Hz, 1H, H-8′), 4.37 (s, 1H, H-6′), 4.19 (d, J=2.9 Hz, 1H, H-2′″), 3.97-3.88 (m, 1H, H-4′″), 3.86-3.54 (m, 12H, H-4, H-3′′″, H-3″, H-5′″, H-6″, H-5″, H-4′, H-5, H-2′, OCH.sub.2CH.sub.2), 3.53-3.39 (m, 5H, H-2′, H-5′, H-5′″, H-2″, H-6), 3.31-3.21 (m, 1H, H-3), 3.18 (d, J=8.4 Hz, 1H, H-7′), 3.16-3.08 (m, 1H, H-1), 3.05 (t, J=10.3 Hz, 1H, H-4″), 3.01 (t, J=4.8 Hz, 2H, OCH.sub.2CH.sub.2), 2.57 (s, 3H, NHCH.sub.3), 2.24 (dd, J=8.6, 4.0 Hz, 1H, H-2), 2.20-2.09 (m, 1H, H-3′), 1.84 (q, J=11.9 Hz, 1H, H-3′), 1.66-1.59 (m, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 110.5 (C-1′″), 94.5 (C-1′), 94.3 (C-1″), 92.8 (C-8′), 84.9 (C-5), 81.0 (C-4′″), 77.0 (C-3′″), 75.8 (C-4), 73.2 (C-2′″), 72.5 (C-6), 70.2 (C-5″), 69.6 (C-2″), 69.5 (C-3″), 68.4 (C-4′), 66.0 (C-5′), 65.9 (OCH.sub.2CH.sub.2), 62.6 (C-6′), 61.0 (C-5′″), 60.2 (C-6″), 59.3 (C-7′), 51.9 (C-4″), 49.8 (C-3), 48.3 (C-1), 47.8 (C-2′), 39.2 (OCH.sub.2CH.sub.2), 30.0 (NCH.sub.3), 28.5 (C-2), 26.7 (C-3); ESI-HRMS: m/z calcd. for C.sub.28H.sub.55N.sub.6O.sub.15 [M+H].sup.+ 715.3725; found, 715.3690.

(34) 5-O-β-(3′″-O-(2-Aminoethyl)-D-ribofuranosyl) apramycin hexaacetate salt (DCWSU124). Substrate Gβ (35 mg, 0.03 mmol) was deprotected in the same manner as compound Gα to yield DCWSU124 (30 mg, 95%) as a pentaacetate salt in the form of a white solid; [α].sub.D.sup.25=68.92 (c 0.5, H2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.64 (d, J=3.6 Hz, 1H, H-1′), 5.28 (d, J=3.7 Hz, 1H, H-1″), 5.16 (s, 1H, H-1′″), 5.00 (d, J=8.5 Hz, 1H, H-8′), 4.37 (s, 1H, H-6′), 4.19 (d, J=2.9 Hz, 1H, H-2′″), 3.97-3.88 (m, 1H, H-4′″), 3.86-3.54 (m, 12H, H-4, H-3′″, H-3″, H-5′″, H-6″, H-5″, H-4′, H-5, H-2′, OCH.sub.2CH.sub.2), 3.53-3.39 (m, 5H, H-2′, H-5′, H-5′″, H-2″, H-6), 3.31-3.21 (m, 1H, H-3), 3.18 (d, J=8.4 Hz, 1H, H-7′), 3.16-3.08 (m, 1H, H-1), 3.05 (t, J=10.3 Hz, 1H, H-4″), 3.01 (t, J=4.8 Hz, 2H, OCH.sub.2CH.sub.2), 2.57 (s, 3H, NHCH.sub.3), 2.24 (dd, J=8.6, 4.0 Hz, 1H, H-2), 2.20-2.09 (m, 1H, H-3′), 1.84 (q, J=11.9 Hz, 1H, H-3′), 1.66-1.59 (m, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 110.5 (C-1′″), 94.5 (C-1′), 94.3 (C-1″), 92.8 (C-8′), 84.9 (C-5), 81.0 (C-4′″), 77.0 (C-3′″), 75.8 (C-4), 73.2 (C-2′″), 72.5 (C-6), 70.2 (C-5″), 69.6 (C-2″), 69.5 (C-3″), 68.4 (C-4′), 66.0 (C-5′), 65.9 (OCH.sub.2CH.sub.2), 62.6 (C-6′), 61.0 (C-5′″), 60.2 (C-6″), 59.3 (C-7′), 51.9 (C-4″), 49.8 (C-3), 48.3 (C-1), 47.8 (C-2′), 39.2 (OCH.sub.2CH.sub.2), 30.0 (NCH.sub.3), 28.5 (C-2), 26.7 (C-3); ESI-HRMS: m/z calcd. for C.sub.28H.sub.55N.sub.6O.sub.15 [M+H].sup.+ 715.3725; found, 715.3690.

Example 4

DCWSU131

(35) See the synthetic scheme of FIG. 2.

(36) 5-O-β-[2′″,3′″,5′″-Tri-O-acetyl-D-ribofuranosyl]-6,2″, 3″, 6″-tetra-O-acetyl-1,3,2′, 4″-tetraazido-6′, 7′-oxazolidino-apramycin (C). A suspension of 2,3,5-tri-O-acetyl-D-ribofuranosyl trichloroacetimidate 125 (150 mg, 0.36 mmol), acceptor A (100 mg, 0.12 mmol) and activated 4 Å MS in dry DCM was stirred at rt for 1 h before cooling to 0° C. and addition of BF.sub.3.OEt.sub.2 (132 μL, 0.54 mmol). After 4 h of stirring at 0° C., the reaction was quenched with triethylamine (0.5 mL) and filtered through Celite®. The reaction mixture was diluted with EtOAc and washed with aqueous NaHCO.sub.3 and brine then concentrated. The crude product was purified using silica gel column chromatography (eluent: 20%-40% EtOAc/hexanes) to give C α:β=1.9 (126 mg, 95%), further purification was done to give C (47 mg) as the 8-anomer in the form of a white solid with the remainder of the product isolated as a mixtures of anomers. [α].sub.D.sup.25=+47.2 (c 2.7, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 5.637 (d, J=3.5 Hz, 1H, H-1′), 5.43 (d, J=10.1 Hz, 1H, H-3″), 5.40 (d, J=2.3 Hz, 1H, H-1′″), 5.37 (d, J=3.8 Hz, 1H, H-1″), 5.11 (t, J=5.0 Hz, 1H, H-3′″), 5.07 (dd, J=4.9, 3.3 Hz, 1H, H-2′″), 4.92 (t, J=9.9 Hz, 1H, H-6), 4.85 (dd, J=10.4, 3.9 Hz, 1H, H-2″), 4.82 (d, J=4.6 Hz, 1H, H-8′), 4.76 (dd, J=7.4, 3.3 Hz, 1H, H-6′), 4.41 (dd, J=10.3, 3.3 Hz, 1H, H-5′), 4.32 (m, 2H, H-6″, H-5′″), 4.24 (q, J=4.0 Hz, 1H, H-4′″), 4.21 (dd, J=12.2, 5.4 Hz, 1H, H-6″), 4.09 (dd, J=12.1, 4.1 Hz, 1H, H-5′″), 3.79 (d, J=9.2 Hz, 1H, H-5), 3.77-3.64 (m, 4H, H-4, H-7′, H-4′, H-5″), 3.60-3.53 (m, 2H, H-4″, H-3), 3.46-3.38 (m, 1H, H-1), 3.22 (dt, J=12.9, 4.1 Hz, 1H, H-2′), 2.93 (s, 3H, NCH.sub.3), 2.41 (dt, J=13.0, 4.5 Hz, 1H, H-2), 2.26-2.21 (m, 1H, H-3′), 2.20 (s, 3H, COCH.sub.3), 2.14-2.02 (m, 18H, 6*COCH.sub.3), 1.93 (q, J=11.7 Hz, 1H, H-3′), 1.58 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.8 (C═O), 170.4 (C═O), 170.2 (C═O), 169.8 (C═O), 169.6 (C═O), 169.5 (C═O), 169.5 (C═O), 157.0 (C═O), 106.1 (C-1′″), 97.4 (C-8′), 96.4 (C-1′), 94.0 (C-1″), 80.4 (C-5), 79.5 (C-4′″), 77.5 (C-4), 74.5 (C-6), 74.1 (C-2′″), 71.0 (C-6′), 70.9 (C-3′″), 70.3 (C-3″), 69.9 (C-2″), 69.1 (C-5″), 66.0 (C-5′), 65.7 (C-4′), 63.4 (C-5′″), 62.9 (C-6″), 60.2 (C-7′), 60.1 (C-4″), 59.1 (C-3), 58.1 (C-1), 56.6 (C-2′), 31.5 (C-2), 30.1 (NCH.sub.3), 29.9 (C-3′), 20.8 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3), 20.7 (COCH.sub.3), 20.7 (COCH.sub.3), 20.4 (COCH.sub.3), 20.4 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.41H.sub.54N.sub.13O.sub.23 [M+H].sup.+ 1118.3275; found, 1118.3234.

(37) 5-O—(β-D-Ribefuranosyl) apramycin pentaacetate salt (DCWSU131) A stirred solution of substrate C (47 mg, 0.04 mmol) in dioxane (0.5 mL) was treated with 3 N NaOH (0.25 mL) and heated at 100° C. for 12 h. The reaction mixture was cooled to rt and neutralized with glacial acetic acid before it was concentrated in vacuo. The crude product was purified through a silica gel column (eluent: 10-20% methanol/DCM). The product-containing fractions were concentrated, dissolved in dioxane:water:glacial acetic acid=1:2:0.2 (0.3 mL) and Pd/C (0.5 equiv) was added. The reaction mixture was stirred at room temperature under 1 atm of hydrogen (balloon) for 1 h. After completion, the reaction mixture was filtered over Celite® and the filtrate concentrated to dryness and dissolved in aqueous acetic acid solution (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then eluted with a gradient of 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid and lyophilized to afford DCWSU131 (29 mg, 69%) as the pentaacetate salt in the form of a white solid [α].sub.D.sup.25=+66.25 (c 0.8, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.66 (d, J=4.0 Hz, 1H, H-1′), 5.29 (d, J=3.8 Hz, 1H, H-1″), 5.14 (s, 1H, H-1′″), 5.01 (d, J=8.5 Hz, 1H, H-8′), 4.38 (s, 1H, H-6′), 4.00 (d, J=4.7 Hz, 1H, H-2′″), 3.98-3.93 (m, 1H, H-3′″), 3.86-3.74 (m, 3H, H-4′″, H-4, H-3′″), 3.74-3.63 (m, 5H, H-4′, H-5, H-5″, H-5′″, H-6″), 3.58 (dd, J=12.4, 4.4 Hz, 1H, H-6″), 3.53-3.41 (m, 5H, H-5′, H-2′, H-2″, H-6, H-5′″), 3.29-3.21 (m, 1H, H-3), 3.19 (dd, J=8.5, 2.4 Hz, 1H, H-7′), 3.12 (td, J=11.6, 4.3 Hz, 1H, H-1), 3.06 (t, J=10.4 Hz, 1H, H-4′″), 2.58 (s, 3H, NCH.sub.3), 2.24 (dt, J=11.3, 3.1 Hz, 1H, H-2), 2.21-2.10 (m, 1H, H-3′), 1.92-1.81 (m, 1H, H-3′), 1.66-1.57 (m, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 110.3 (C-1′″), 94.5 (C-1′), 94.3 (C-1″), 92.8 (C-8′), 84.9 (C-5), 82.3 (C-4′″), 75.9 (C-4), 75.1 (C-2′″) 72.5 (C-6), 70.2 (C-5″), 69.6 (C-2″), 69.6 (C-4′), 68.9 (C-3″), 68.4 (C-3′″), 66.0 (C-5′), 62.6 (C-6′), 60.8 (C-5′″), 60.2 (C-6″), 59.3 (C-7′), 52.0 (C-4″), 49.8 (C-3), 48.3 (C-1), 47.8 (C-2′), 30.0 (NCH.sub.3), 28.6 (C-2), 26.7 (C-3′); ESI-HRMS: m/z calcd. for C.sub.26H.sub.49N.sub.5NaO.sub.15 [M+Na].sup.+ 694.3123; found, 694.3122.

Example 5

DCWSU 138

(38) See the synthetic scheme of FIG. 3.

(39) p-Cresyl-2′,6′-diazido-2,5,3′4′-tetra(4-methoxybenzoyl)-1-thio-β-paromobioside (c). p-Cresyl-2′,6′-diazido-2,5,3′4′-tetra-O-acetyl-α-thioparomobioside a (375 mg, 0.59 mmol) was dissolved in dry methanol, then NaOMe (4.7 mg, 0.12 mmol) was added and the reaction mixture was stirred for 1.5 h. The reaction was quenched with glacial acetic acid and concentrated till dryness. The crude product was dissolved in pyridine (5 mL) and p-methoxybenzoyl chloride (802 mg, 4.72 mmol) was added followed by stirring for 48 h then diluting with EtOAc. The organic layer was washed with aqueous NaHCO.sub.3 followed by brine, dried with Na.sub.2SO.sub.4, and concentrated. The crude product was purified via silica gel chromatography eluting with 10% to 40% EtOAc in hexanes to give c (398 mg, 76%) as a white solid; [α].sub.D.sup.25=−14.2 (c 13.2, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): -δ 8.08 (d, J=8.8 Hz, 2H, ArH), 8.04 (d, J=8.8 Hz, 2H, ArH), 7.95 (d, J=8.8 Hz, 2H, ArH), 7.85 (d, J=8.9 Hz, 2H, ArH), 7.40 (d, J=8.0 Hz, 2H, ArH), 7.02 (d, J=7.8 Hz, 2H, ArH), 6.97-6.88 (m, 6H, ArH), 6.78 (d, J=8.9 Hz, 2H, ArH), 5.51 (d, J=4.5 Hz, 1H, H-1), 5.43 (t, J=4.9 Hz, 1H, H-2), 5.23 (t, J=2.8 Hz, 1H, H-3′), 5.16 (d, J=1.8 Hz, 1H, H-1′), 5.04 (d, J=1.8 Hz, 1H, H-4′), 4.78 (t, J=5.6 Hz, 1H, H-3), 4.68 (dd, J=12.0, 2.7 Hz, 1H, H-5), 4.56 (td, J=5.8, 5.2, 2.7 Hz, 1H, H-4), 4.50 (dd, J=12.1, 4.6 Hz, 1H, H-5′), 4.24 (ddd, J=8.5, 4.1, 1.9 Hz, 1H, H-5′), 3.87 (s, 3H, OCH.sub.3), 3.85-3.73 (m, 9H, 3 OCH.sub.3), 3.57 (dd, J=13.1, 8.4 Hz, 1H, H-6′), 3.41 (t, J=2.2 Hz, 1H, H-2′), 3.27 (dd, J=13.1, 4.0 Hz, 1H, H-6′), 2.22 (s, 3H, CH.sub.3); 13C NMR (151 MHz, CDCl.sub.3): δ 166.0 (C═O), 165.4 (C═O), 165.0 (C═O), 164.03 (C═O), 163.97 (Ar—C), 163.9 (Ar—C), 163.7 (Ar—C), 163.4 (Ar—C), 138.6 (Ar—C), 133.9 (Ar—C), 132.3 (Ar—C), 132.0 (Ar—C), 131.9 (Ar—C), 131.8 (Ar—C), 129.8 (Ar—C), 127.7 (Ar—C), 122.3 (Ar—C), 121.1 (Ar—C), 120.9 (Ar—C), 120.8 (Ar—C), 99.3 (C-1′), 88.2 (C-1), 81.2 (C-4), 76.7 (C-3), 74.5 (C-2), 74.2 (C-5′), 69.1 (C-3′), 65.7 (C-4′), 63.8 (C-5), 56.9 (C-2′), 55.52 (OCH.sub.3), 55.46 (OCH.sub.3), 55.4 (2 OCH.sub.3), 50.8 (C-6′), 21.1 (CH.sub.3); ESI-HRMS: m/z calcd. for C.sub.50H.sub.48N.sub.6NaO.sub.15S [M+Na].sup.+ 1027.2796; found, 1027.2749.

(40) p-Cresyl-2′,6′-diazido-2,5,3′4′-tetra(4-methoxybenzoyl)-β-thio-paromobiosyl S-oxide (d). A solution of compound c (198 mg, 0.2 mmol) in dry DCM (15 mL) was cooled to −78° C. before ozone gas was bubbled in for 5 min till the solution turned blue. The solution was then warmed to rt, concentrated and the crude product purified by gradient chromatography over silica gel (eluent: 40% EtOAc/hexanes) to give d (162 mg, 80%) as a white solid; [α].sub.D.sup.25=+60.0 (c 0.5, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 8.16 (d, J=9.0 Hz, 2H, ArH), 8.12-8.03 (m, 4H, ArH), 7.68 (d, J=9.0 Hz, 2H, ArH), 7.51 (d, J=8.2 Hz, 2H, ArH), 7.24 (d, J=7.9 Hz, 2H, ArH), 7.00 (d, J=9.0 Hz, 2H, ArH), 6.96 (d, J=4.3 Hz, 2H, ArH), 6.93 (d, J=4.4 Hz, 2H, ArH), 6.78 (d, J=9.0 Hz, 2H, ArH), 6.14 (dd, J=5.0, 1.9 Hz, 1H, H-2), 5.28 (d, J=1.6 Hz, 1H, H-1′), 5.23 (t, J=2.7 Hz, 1H, H-3′), 5.09-5.03 (m, 1H, H-4′), 5.00 (dd, J=7.1, 5.1 Hz, 1H, H-3), 4.90 (d, J=1.9 Hz, 1H, H-1), 4.76 (dd, J=11.3, 1.5 Hz, 1H, H-5), 4.64-4.52 (m, 2H, H-5, H-4), 4.28 (ddd, J=7.7, 4.4, 1.7 Hz, 1H, H-5′), 3.92 (s, 3H, OCH.sub.3), 3.86 (s, 3H, OCH.sub.3), 3.85 (s, 3H, OCH.sub.3), 3.82 (s, 3H, OCH.sub.3), 3.54 (dd, J=13.0, 8.1 Hz, 1H, H-6′), 3.42-3.36 (m, 1H, H-2′), 3.32 (dd, J=13.0, 4.5 Hz, 1H, H-6′), 2.30 (s, 3H, CH.sub.3); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 166.0 (C═O), 165.0 (C═O), 164.8 (C═O), 164.1 (C═O), 163.94 (Ar—C), 163.86 (Ar—C), 163.6 (Ar—C), 142.2 (Ar—C), 136.6 (Ar—C), 132.3 (Ar—C), 132.1 (Ar—C), 131.9 (Ar—C), 131.7 (Ar—C), 130.0 (Ar—C), 124.6 (Ar—C), 122.1 (Ar—C), 121.1 (Ar—C), 121.0 (Ar—C), 120.6 (Ar—C), 113.94 (Ar—C), 113.86 (Ar—C), 113.8 (Ar—C), 113.7 (Ar—C), 100.1 (C-1), 99.1 (C-1), 81.6 (C-4), 75.9 (C-3), 74.1 (C-5′), 70.1 (C-2), 69.1 (C-3′), 65.7 (C-4′), 62.7 (C-5), 56.7 (C-2′), 55.54 (OCH.sub.3), 55.46 (OCH.sub.3), 55.4 (OCH.sub.3), 50.7 (C-6′); ESI-HRMS: m/z calcd. for C.sub.50H.sub.48N.sub.6NaO.sub.16S [M+Na].sup.+1043.2745; found, 1043.2717.

(41) 5-O-β-[2″″,6″″-Diazido-2′″,5′″,3″″4″″-tetra(4-methoxybenzoyl) paromobiosyl]-6,2″,3″,6″-tetra-O-acetyl-1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin (e). A suspension of donor d (140 mg, 0.14 mmol), acceptor 124 (150 mg, 0.18 mmol) and activated 4 Å MS in dry DCM (2 mL) was stirred at rt for 1 h before addition of freshly distilled triflic anhydride (33 μL, 0.2 mmol). After 5 h of stirring at rt, the reaction was quenched with triethylamine (0.1 mL) and filtered through Celite® then concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (20% EtOAc/toluene) to afford e (113 mg, 48%) as a white foam; [α].sub.D.sup.25=+84.9 (c 0.3, DCM);.sup.1H NMR (600 MHz, CDCl.sub.3): δ 8.10-8.04 (m, 4H, ArH), 8.02 (d, J=8.9 Hz, 2H, ArH), 7.83 (d, J=8.9 Hz, 2H, ArH), 7.01-6.94 (m, 4H, ArH), 6.92 (d, J=8.9 Hz, 2H, ArH), 6.82 (d, J=9.0 Hz, 2H, ArH), 5.58 (d, J=3.5 Hz, 1H, H-1′), 5.44 (d, J=1.7 Hz, 1H, H-1′″), 5.39 (t, J=10.0 Hz, 1H, H-3″), 5.33 (d, J=3.8 Hz, 1H, H-1″), 5.24-5.18 (m, 2H, H-2′″, H-3″″), 5.14 (d, J=1.5 Hz, 1H, H-1″″), 5.07-5.04 (m, 1H, H-4′″), 4.89-4.80 (m, 4H, H-2′, H-5′″, H-6, H-8′), 4.77-4.72 (m, 2H, H-3′″, H-6′), 4.50-4.44 (m, 2H, H-4′″, H-5′″), 4.43 (dd, J=10.4, 3.3 Hz, 1H, H-5′), 4.32-4.26 (m, 2H, H-5″″, H-6″), 4.20 (dd, J=12.2, 5.4 Hz, 1H, H-6″), 3.87 (s, 3H, OCH.sub.3), 3.85 (s, 3H, OCH.sub.3), 3.83 (s, 3H, OCH.sub.3), 3.81 (s, 3H, OCH.sub.3), 3.75-3.68 (m, 3H, H-5, H-5″, H-7′), 3.64-3.49 (m, 4H, H-3, H-4′, H-4″, H-6″″), 3.41-3.30 (m, 4H, H-1, H-2″″, H-4, H-6″″), 3.12 (dt, J=12.9, 4.1 Hz, 1H, H-2′), 2.92 (s, 3H, NCH.sub.3), 2.38 (dt, J=12.9, 4.4 Hz, 1H, H-2), 2.17-2.12 (m, 1H, H-3′), 2.11-2.07 (m, 9H, 3COCH.sub.3), 2.03 (s, 3H, COCH.sub.3), 1.88-1.81 (m, 1H, H-3′), 1.44 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.4 (C═O), 170.1 (C═O), 169.9 (C═O), 169.6 (C═O), 165.9 (C═O), 165.5 (C═O), 165.0(C═O), 164.1(C═O), 164.0 (Ar—C), 163.9 (Ar—C), 163.8 (Ar—C), 163.6 (Ar—C), 157.1(C═O), 132.3 (Ar—C), 132.1 (Ar—C), 131.8 (Ar—C), 122.2 (Ar—C), 121.1 (Ar—C), 121.0 (Ar—C), 120.7 (Ar—C), 113.9 (Ar—C), 113.9 (Ar—C), 113.9 (Ar—C), 113.8 (Ar—C), 106.8 (C-1′″), 99.3 (C-1″″), 96.9 (C-1′), 96.6 (C-8′), 94.1 (C-1″), 81.4 (C-5), 79.9 (C-4′″), 78.0 (C-4), 75.7 (C-3”), 74.9 (C-6), 74.5 (C-5′″), 74.2 (C-3”), 70.8 (C-3′″), 70.5 (C-6), 69.9 (C-2″), 69.2 (C-2′″), 69.0 (C-5″), 65.7 (C-4′″), 65.6 (C-5′), 63.0 (C-5′″), 62.9 (C-6″), 60.1 (C-7′, C-3), 58.8 (C-4″), 58.1 (C-1), 56.8 (C-2″″), 56.6 (C-2′), 55.5 (OCH.sub.3), 55.5 (OCH.sub.3), 50.7 (C-6″″), 31.2 (C-2′), 30.4 (C-3′), 30.0 (NCH.sub.3), 21.0 (COCH.sub.3), 20.8 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.73H.sub.79N.sub.19NaO.sub.31 [M+Na].sup.+ 1740.5087; found, 1740.5109.

(42) 5-O-β-(Paromobiosyl) apramycin heptaacetate salt (DCWSU138). A stirred solution of compound e (40 mg, 0.02 mmol) in dioxane (0.5 mL) was treated with 3N NaOH (0.5 mL) and heated at 120° C. for 2 h. The reaction mixture was cooled to rt and neutralized with glacial acetic acid before it was concentrated in vacuo. The crude product was purified with silica gel column chromatography (eluent: 5%-15% methanol/DCM) to give a residue that was directly subjected to Staudinger reaction by dissolving in THF (0.6 mL) followed by the addition of 0.3N NaOH (0.3 mL) and 1M P(CH.sub.3).sub.3 in THF (0.3 mL). The reaction mixture was stirred at 55° C. for 2 h, then concentrated and purified by column chromatography (eluent: 5% to 50% ammonia/MeOH). The product-containing fractions were concentrated and dissolved in D.I. water (1 mL), acidified by glacial acetic acid till pH=3-4 and loaded to a Sephadex column (CM Sephadex C-25) from which the product was flushed with D.I. water (20 mL), then gradient elution of 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid and lyophilized to afford DCWSU138 (8 mg, 35%) as a peracetate salt in the form of a white foam; [α].sub.D.sup.25=+54.4 (c 0.5, H.sub.2O);.sup.1H NMR (600 MHz, D.sub.2O): δ 5.68 (d, J=3.9 Hz, 1H, H-1′), 5.32 (d, J=3.9 Hz, 1H, H-1″), 5.22 (d, J=2.4 Hz, 1H, H-1′″), 5.10 (d, J=1.4 Hz, 1H, H-1″″), 5.03 (d, J=8.5 Hz, 1H, H-8′), 4.41 (s, 1H, H-6′), 4.31 (t, J=5.7 Hz, 1H, H-3′″), 4.21 (dd, J=3.8, 2.8 Hz, 1H, H-2′″), 4.15-4.09 (m, 1H, H-5″″), 4.08-4.00 (m, 2H, H-3″″, H-4′″), 3.83 (t, J=9.7 Hz, 1H, H-4), 3.79 (dt, J=10.2, 3.9 Hz, 1H, H-5″), 3.77-3.65 (m, 5H, H-5′″, H-3″, H-4′, H-5, H-6″), 3.65-3.58 (m, 2H, H-4″″, H-6″), 3.58-3.44 (m, 5H, H-6, H-2′, H-5′, H-2″, H-5′″), 3.39 (s, 1H, H-2″″), 3.32-3.25 (m, 1H, H-3), 3.25-3.19 (m, 2H, H-7′, H-6″″), 3.19-3.12 (m, 2H, H-1, H-6″″), 3.09 (t, J=10.3 Hz, 1H, H-4″), 2.60 (s, 3H, NCH.sub.3), 2.27 (dt, J=11.8, 3.1 Hz, 1H, H-2), 2.22-2.13 (m, 1H, H-3′), 1.87 (dd, J=24.1, 11.8 Hz, 1H, H-3′), 1.64 (q, J=13.0 Hz, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 110.1 (C-1′″), 95.3 (C-1″″), 94.5 (C-1′), 94.4 (C-1″), 92.8 (C-8′), 84.9 (C-5), 81.3 (C-4′″), 76.0 (C-4), 75.2 (C-3′″), 73.4 (C-2′″), 72.5 (C-2″), 70.2 (C-5″″), 70.1 (C-5″), 69.7 (C-6), 69.5 (C-5′), 68.4 (C-3″), 67.5 (C-3′″), 67.2 (C-4′″), 65.9 (C-4′), 62.6 (C-6′), 60.2 (C-5′″), 60.0 (C-6″), 59.3 (C-7′), 52.0 (C-4″), 50.7 (C-2″″), 49.8 (C-1), 48.4 (C-3), 47.8 (C-2′), 40.3 (C-6″″), 30.0 (NCH.sub.3), 28.6 (C-2), 26.7 (C-3); ESI-HRMS: m/z calcd. for C.sub.32H.sub.62N.sub.7O.sub.18 [M+H].sup.+ 832.4151; found, 832.4131.

Example 6

DCWSU146

(43) See the synthetic scheme of FIG. 4.

(44) Erythrolactone 2,3-di-O-benzoate (T). An aqueous solution of isoascorbic acid (7.04 g, 40 mmol) in water (100 mL) was ice-cooled and Na.sub.2CO.sub.3 (8.48 g, 80 mmol) was added slowly followed by aqueous solution of H.sub.2O.sub.2 (30%, 9.2 mL). The reaction mixture was stirred at 42° C. for 30 min after which charcoal (2 g) was added and the mixture stirred at 75° C. for 30 min to destroy excess H.sub.2O.sub.2. The reaction mixture was filtered while hot and neutralized with 6 N HCl then concentrated till dryness. The resulting residue was dissolved in dry pyridine (50 mL) and cooled to 0° C. before addition of benzoyl chloride dropwise (11.6 mL, 100 mmol). The reaction mixture was stirred at rt for 12 h before it was diluted with EtOAc and washed with aqueous NaHCO.sub.3 and brine. The organic layer was dried over Na.sub.2SO.sub.4 and concentrated. The residue was purified by gradient chromatography over silica gel (eluent: 10% to 35% EtOAc in hexanes) to give T (9.0 g, 69%) as a white solid; [α].sub.D.sup.25=−145.78 (c 1.2, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.97 (m, 4H), 7.65-7.50 (m, 2H, ArH), 7.41 (m, 2H, ArH), 7.35 (m, 2H, ArH), 6.07-5.95 (m, 2H, H-2, H-3), 4.73 (dd, J=11.4, 3.1 Hz, 1H, H-4), 4.65 (d, J=11.4 Hz, 1H, H-4); .sup.13C NMR (101 MHz, CDCL3): δ 170.3 (C═O), 165.3 (ArC), 164.9 (ArC), 133.9 (ArC), 130.1 (ArC), 129.8 (ArC), 128.6 (ArC), 128.5 (ArC), 128.5 (ArC), 128.0 (ArC), 69.9 (C-4), 69.7 (C-2), 67.7(C-3); ESI-HRMS: m/z calcd. for C.sub.18H.sub.14NaO.sub.6 [M+Na].sup.+ 349.0688; found, 349.0691.

(45) 2,3-Di-O-benzoyl-α/β-D-erythrofuranose (U). A stirred solution of erythrolactone 2,3-di-O-benzoate T (1.00 g, 3.06 mmol) in dry THF was cooled to −78° C. and DIBAL (1 M in hexanes, 6 mL) was added. The mixture was stirred for 4 h before it was quenched with methanol (20 mL). The so-formed residue was filtered through Celite® and the filtrate was concentrated and dissolved in EtOAc. The organic layer was washed with aqueous NaHCO.sub.3 and brine. The organic layer was dried over Na.sub.2SO.sub.4 and concentrated. The residue was purified by gradient chromatography over silica gel (eluent: 10% to 25% EtOAc in hexanes) to give U (360 mg, 36%) as an α/β mixture (0.5:1) in the form of a gum; [α].sub.D.sup.25=−29.1 (c 0.3, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 8.18-8.01 (m, 2H, ArH), 8.00-7.93 (m, 2H, ArH), 7.92-7.84 (m, 2H, ArH), 7.57-7.42 (m, 2H, ArH), 7.42-7.24 (m, 7H, ArH), 5.90-5.78 (m, 1.5H, H-3b, H-3α), 5.74 (dd, J=7.2, 4.7 Hz, 0.5H, H-1α), 5.72-5.67 (m, 1H, H-1β), 5.59 (dd, J=5.3, 1.6 Hz, 1H, H-2β), 5.33 (dd, J=5.9, 4.7 Hz, 0.5H, H-2β), 4.72-4.63 (m, 1H, OH), 4.58 (dd, J=10.0, 6.0 Hz, 1H, H-4β), 4.37-4.26 (m, 1H, H-4α), 4.13 (dd, J=10.0, 4.2 Hz, 1H, H-4β); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 165.8 (C═O), 165.7 (C═O), 133.5 (ArC), 133.5 (ArC), 133.4 (ArC), 133.4 (ArC), 133.3 (ArC), 130.00 (ArC), 139.95 (ArC), 129.9 (ArC), 129.83 (ArC), 129.79 (ArC), 129.7 (ArC), 129.18 (ArC), 129.15 (ArC), 128.6 (ArC), 128.51 (ArC), 128.45 (ArC), 128.41 (ArC), 128.36 (ArC), 100.4 (C-1β), 94.9 (C-1α), 77.0 (C-2β), 76.9 (C-2α), 72.3 (C-3β), 72.2 (C-3α), 69.9 (C-4β), 69.8 (C-4α); ESI-HRMS: m/z calcd. for C.sub.18H.sub.16NaO.sub.6 [M+Na].sup.+ 349.0688; found, 349.0691.

(46) 2,3-Di-O-benzoyl-β-D-erythrofuranosyl trichloroacetimidate (V). 2,3-O-Dibenzoyl-α-β-D-erythrofuranose (U) (360 mg, 1.10 mmol) and trichloroacetonitrile (2 mL) were dissolved in dry DCM (2 mL) and ice-cooled before addition of DBU (2 drops). The reaction mixture was stirred at rt for 5 min and concentrated. The crude mixture was passed through a silica gel column that had been basified with 0.5% triethylamine/hexanes, eluting with 0.5% triethylamine in EtOAc/hexanes to give compound V (458 mg, 88%) as a gum; [α].sub.D.sup.25=−78.9 (c 1.6, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 8.69 (s, 1H, NH), 8.05-7.97 (m, 2H, ArH), 7.93-7.86 (m, 2H, ArH), 7.54 (m, 2H, ArH), 7.40 (m, 2H, ArH), 7.32 (m, 2H, ArH), 6.58 (s, 1H, H-1), 5.94-5.84 (m, 2H, H-2, H-3), 4.66-4.58 (m, 1H, H-4), 4.30 (dd, J=9.8, 3.4 Hz, 1H, H-4); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 165.6 (ArC), 165.1 (ArC), 160.8 (C═N), 133.6 (ArC), 133.4 (ArC), 129.9 (ArC), 129.7 (ArC), 128.9 (ArC), 128.8 (ArC), 128.5 (ArC), 128.4 (ArC), 103.2 (C-1), 77.2 (CCI.sub.3), 75.5 (C-2), 71.8 (C-4), 71.5 (C-3); ESI-HRMS: m/z calcd. for C.sub.20H.sub.16Cl.sub.3NaO.sub.6 [M+Na].sup.+ 493.9941; found, 493.9945.

(47) 5-O-β-[2′″,3′″-Di-O-benzoyl-D-eryth rofu ranosyl]-6,2″,3″,6″-tetra-O-acetyl-1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin (W). Donor V (109 mg, 0.36 mmol), acceptor A (100 mg, 0.12 mmol) and activated 4 Å MS were stirred in dry DCM (2.5 mL) at rt for 1 h before cooling to −78° C. BF.sub.3.OEt.sub.2(200 μL, 0.54 mmol) was added and reaction mixture was stirred for 3 h at −78° C. The reaction was quenched at −78° C. with triethylamine (0.5 mL) and filtered through Celite® before it was diluted with EtOAc. The organic layer was washed with NaHCO.sub.3 and brine then concentrated. The crude product was purified using silica gel column chromatography (eluent: 0.4%-0.8% Methanol/DCM) to give the β anomer W (68 mg, 50%) in the form of a white solid; [α].sub.D.sup.25=+64.1 (c 4.5, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.90 (m, 4H, ArH), 7.53 (m, 2H, ArH), 7.35 (m, 4H, ArH), 5.63 (m, 2H, H-3′″, H-1′″), 5.54 (d, J=3.5 Hz, 1H, H-1′), 5.51 (dd, J=5.0, 1.4 Hz, 1H, H-2′″), 5.44 (t, J=10.0 Hz, 1H, H-3″), 5.39 (d, J=3.8 Hz, 1H, H-1″), 5.02 (t, J=9.9 Hz, 1H, H-6), 4.93-4.86 (m, 2H, H-2″, H-8′), 4.82 (dd, J=7.7, 3.3 Hz, 1H, H-6′), 4.62-4.50 (m, 2H, H-5′, H-4′″), 4.33 (dd, J=12.1, 1.9 Hz, 1H, H-6″), 4.23 (dd, J=12.2, 5.3 Hz, 1H, H-6″), 4.16 (dd, J=9.9, 4.9 Hz, 1H, H-4′″), 3.93 (t, J=9.2 Hz, 1H, H-5), 3.84-3.70 (m, 4H, H-4, H-4′, H-5″, H-7′), 3.70-3.54 (m, 2H, H-3, H-4″), 3.49 (ddd, J=12.5, 10.5, 4.3 Hz, 1H, H-1), 3.34 (dt, J=12.9, 4.1 Hz, 1H, H-2′), 2.94 (s, 3H, NCH.sub.3), 2.47 (dt, J=12.9, 4.5 Hz, 1H, H-2), 2.33-2.23 (m, 1H, H-3′), 2.11 (m, 12H, 4COCH.sub.3), 1.97 (q, J=11.8 Hz, 1H, H-3′), 1.65 (q, J=12.5 Hz, 1H, H-2); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 170.4 (C═O), 170.2 (C═O), 169.8 (C═O), 169.6 (C═O), 165.5 (Ar—C), 165.3 (Ar—C), 157.0 (Ar—C), 133.6 (Ar—C), 133.4 (Ar—C), 129.6 (Ar—C), 129.0 (Ar—C), 128.9 (Ar—C), 128.5 (Ar—C), 128.4 (Ar—C), 106.4 (C-1′″), 97.4 (C-1′), 96.8 (C-8′), 94.1 (C-1″), 79.2 (C-5), 78.1 (C-4), 75.8 (C-2′″), 74.8 (C-6), 71.6 (C-3′″), 70.8 (C-6′), 70.6 (C-2″), 70.4 (C-4′″), 69.9 (C-3″), 69.1 (C-5″), 66.0 (C-5′), 65.6 (C-4′), 62.9 (C-6″), 60.2 (C-7′), 60.1 (C-3), 59.0 (C-4″), 58.2 (C-1), 56.5 (C-2′), 31.5 (C-2), 30.1 (NCH.sub.3′), 29.7(C-3′) 20.9 (2COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.48H.sub.53N.sub.13NaO.sub.21 6 [M+Na].sup.+ 1170.3377; found, 1170.3353.

(48) 5-O-β-D—(Erythrofuranosyl) apramycin pentaacetate salt (DCWSU146). A stirred solution of compound W (60 mg, 0.02 mmol) in dioxane (1 mL) was treated with 3N NaOH (1 mL) and heated at 100° C. for 2 h. The reaction mixture was cooled to 55° C. and 1M P(CH.sub.3).sub.3 in THF (0.3 mL) was added and stirring continued for 2 h. The reaction mixture was neutralized with glacial acetic acid, concentrated in vacuo, the residue dissolved in aqueous acetic acid solution (pH 4, 1 mL) and was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid, and lyophilized to afford compound DCWSU146 (35 mg, 71%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+58.71 (c 2.3, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.67 (d, J=4.1 Hz, 1H, H-1′), 5.28 (d, J=3.9 Hz, 1H, H-1″), 5.18 (d, J=3.8 Hz, 1H, H-1′″), 5.00 (d, J=8.5 Hz, 1H, H-8′), 4.38 (s, 1H, H-6′), 4.16 (q, J=4.4 Hz, 1H, H-3′″), 4.04 (dd, J=9.6, 4.9 Hz, 1H, H-4′″), 3.98 (t, J=4.2 Hz, 1H, H-2′″), 3.85 (t, J=9.7 Hz, 1H, H-4), 3.77 (dt, J=10.2, 3.9 Hz, 1H, H-5″), 3.74-3.65 (m, 3H, H-4′, H-5, H-3″), 3.74-3.65 (m, 2H, H-4′″, H-6″), 3.57 (dd, J=12.5, 4.5 Hz, 1H, H-6″), 3.54-3.43 (m, 4H, H-2′, H-2″, H-5′, H-6), 3.34-3.27 (m, 1H, H-3), 3.18 (dd, J=8.5, 2.7 Hz, 1H, H-7′), 3.13 (td, J=12.0, 4.2 Hz, 1H, H-1), 3.08 (t, J=10.4 Hz, 1H, H-4″), 2.57 (s, 3H, NCH.sub.3), 2.26 (dt, J=12.5, 4.1 Hz, 1H, H-2), 2.16 (dt, J=9.7, 4.4 Hz, 1H, H-3′), 1.86-1.80 (m, 1H, H-3′), 1.65 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 110.0 (C-1″), 94.3 (C-1′), 93.9 (C-1″), 92.7 (C-8′), 84.4 (C-5), 75.6 (C-2′″), 75.1 (C-4), 72.4 (C-6), 71.4 (C-4′″), 70.1 (C-5″), 69.6 (C-2″), 69.6 (C-4′), 69.3 (C-3″), 68.1 (C-3′″), 65.7 (C-5′), 62.5 (C-6′), 60.2 (C-6″), 59.2 (C-7′), 51.9 (C-4″), 49.4 (C-3), 48.4 (C-1), 47.4 (C-2′), 29.9 (NCH.sub.3), 28.0 (C-2), 26.8 (C-3′); ESI-HRMS: m/z calcd. for C.sub.25H.sub.48N.sub.5O.sub.14 [M+H].sup.+ 642.3198; found, 642.3182.

Example 7

DCWSU 161, 170, 168, and 169

(49) See the synthetic scheme of FIG. 12.

(50) 5,6,2″,3″,6″-Penta-O-acetyl-1,3,2′,4″-tetraazido-5-epi-6′,7′-oxazolidino-apramycin (j). To a stirred solution of compound A (100 mg, 0.12 mmol) in dry DCM (1.5 mL), pyridine (0.1 mL) was added and reaction mixture was cooled to 0° C. before triflic anhydride (40 μL, 0.24 mmol) was added. The reaction mixture was stirred for 1 h and additional triflic anhydride (40 μL, 0.24 mmol) was added. After 2 h, the reaction mixture was poured into an iced aqueous solution of NaHCO.sub.3 and extracted with EtOAc. The organic layer was washed with brine and dried over Na.sub.2SO.sub.4 and concentrated in vacuo. The crude was dissolved in dry DMF (1 mL), treated with potassium acetate (174 mg, 1.78 mmol) and stirred at 50° C. for 1 h. After completion, the reaction was diluted with EtOAc and washed with NaHCO.sub.3 and brine then concentrated. The crude was purified using silica gel column chromatography (eluent: 0.6%-1.0% methanol/DCM) to give compound j (75 mg, 72%) as a white solid; [α].sub.D.sup.25=+154.25 (c 1.2, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 5.75 (t, J=2.7 Hz, 1H, H-5), 5.51-5.38 (m, 2H, H-1″, H-3″), 5.06 (d, J=3.5 Hz, 1H, H-1′), 4.87-4.68 (m, 4H, H-6, H-6′, H-8′, H-2′), 4.34 (dd, J=12.3, 2.2 Hz, 1H, H-6″), 4.22 (dd, J=12.2, 5.4 Hz, 1H, H-6″), 3.97 (dd, J=10.2, 3.7 Hz, 1H, H-5′), 3.91-3.83 (m, 2H, H-1, H-3), 3.80 (dd, J=10.2, 2.6 Hz, 1H, H-4), 3.78-3.71 (m, 2H, H-7′, H-5″), 3.66 (td, J=10.8, 4.4 Hz, 1H, H-4′), 3.56 (t, J=10.1 Hz, 1H, H-4″), 3.20 (dt, J=12.7, 4.0 Hz, 1H, H-2′), 2.97 (s, 3H, NCH.sub.3), 2.38 (dt, J=13.5, 4.7 Hz, 1H, H-2), 2.27 (dt, J=11.4, 4.4 Hz, 1H, H-3′), 2.17 (s, 3H, COCH.sub.3), 2.12 (d, J=6.5 Hz, 6H, 2*COCH.sub.3), 2.08-1.94 (m, 7H, H-3′, 2*COCH.sub.3), 1.41 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 170.4 (C═O), 170.2 (C═O), 169.7 (C═O), 169.6 (C═O), 169.5 (C═O), 156.9 (C═O), 99.9 (C-8′), 94.1 (C-1″), 93.8 (C-1′), 74.6 (C-4), 72.9 (C-6), 71.8, (C-6′) 69.9 (C-3″,2″), 69.4 (C-5″), 66.9 (C-5′), 66.1 (C-5), 65.9 (C-4′), 62.8 (C-6″), 60.2 (C-4″), 60.1 (C-7′), 58.0 (C-1), 56.2 (C-3), 55.5 (C-2′), 32.2 (C-2), 30.5 (NCH.sub.3), 28.1 (C-3′), 20.7 (COCH.sub.3), 20.6 (COCH.sub.3), 20.5 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.32H.sub.41N.sub.13NaO.sub.17 [M+H].sup.+ 902.2641; found, 902.2639.

(51) 5-Epi-apramycin pentaacetate salt (DCWSU161). A stirred solution of compound (j) (60 mg, 0.057 mmol) in dioxane (0.2 mL) was treated with 3N NaOH (0.2 mL) and heated at 100° C. for 2 h. The reaction mixture was treated with 1M P(CH.sub.3).sub.3 in THF (0.15 mL) and stirred at 55° C. for 2 h. The reaction mixture was then concentrated and dissolved in aqueous acetic acid solution (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid, and lyophilized to afford DCWSU161 (39 mg, 65%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+90.0 (c 0.7, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.29 (d, J=4.0 Hz, 1H, H-1″), 5.21 (d, J=3.8 Hz, 1H, H-1′), 5.02 (d, J=8.5 Hz, 1H, H-8′), 4.34 (s, 1H, H-6′), 4.29 (s, 1H, H-5), 3.82-3.69 (m, 4H, H-4, H-4′, H-3″, H-5″), 3.65 (dd, J=12.5, 3.5 Hz, 1H, H-6″), 3.58 (dd, J=13.0, 4.5 Hz, 1H, H-6″), 3.56-3.47 (m, 4H, H-3, H-6, H-2′, H-2″), 3.44 (dd, J=10.0, 2.6 Hz, 1H, H-5′), 3.34 (ddd, J=12.3, 10.6, 4.5 Hz, 1H, H-1), 3.15 (dd, J=8.5, 2.8 Hz, 1H, H-7′), 3.09 (t, J=10.4 Hz, 1H, H-4″), 2.58 (s, 3H, NCH.sub.3), 2.27 (dt, J=12.5, 4.4 Hz, 1H, H-2), 2.20 (dt, J=11.4, 4.6 Hz, 1H, H-3′), 1.92-1.86 (m, 1H, H-3′), 1.55 (q, J=12.5 Hz, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 94.3 (C-1″), 92.7 (C-8′), 89.9 (C-1′), 72.9 (C-4), 70.1 (C-6), 69.8 (C-2″), 69.4 (C-5′), 69.3 (C-5″), 68.2 (C-3″), 66.0 (C-5), 65.8 (C-4′), 62.5 (C-6′), 60.2 (C-6″), 59.4 (C-7′), 52.0 (C-4″), 48.1 (C-1), 47.4 (C-2′), 46.7 (C-3), 29.9 (NCH.sub.3), 28.1 (C-2), 26.9 (C-3′); ESI-HRMS: m/z calcd. for C.sub.21H.sub.42N.sub.5O.sub.11 [M+H].sup.+ 540.2881; found, 540.2855.

(52) 6,2″,3″,6″-Tetra-O-acetyl-1,3,2′,4″-tetraazido-5-epi-6′,7′-oxazolidino-apramycin (k). To a stirred solution of compound A (100 mg, 0.12 mmol) in dry DCM (1.5 mL), pyridine (0.1 mL) was added and reaction mixture was cooled to 0° C. before triflic anhydride (40 μL, 0.24 mmol) was added. The reaction mixture was stirred for 1 h and additional triflic anhydride (40 μL, 0.24 mmol) was added. After 2 h, the reaction mixture was poured into an iced aqueous solution of NaHCO.sub.3 and extracted with EtOAc. The organic layer was washed with brine and dried over Na.sub.2SO.sub.4 and concentrated in vacuo. The crude product was dissolved in dry DMF (1 mL), treated with sodium nitrite (40 mg, 0.60 mmol) and stirred at 50° C. for 1 h. After completion, the reaction was diluted with EtOAc and washed with brine then concentrated. The crude product was purified using silica gel column chromatography (eluent: 0.6%-1.0% Methanol/DCM) to give compound k (60 mg, 60%) as a white solid; [α].sub.D.sup.25=+100.5 (c 0.6, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 5.43 (t, J=10.1 Hz, 1H, H-3″), 5.39 (d, J=3.8 Hz, 1H, H-1″), 4.99 (d, J=3.5 Hz, 1H, H-1′), 4.83 (dd. J=10.4. 3.8 Hz, 1H, H-2″), 4.81-4.76 (m, 2H, H-6′, H-8′), 4.64 (dd, J=10.4, 2.6 Hz, 1H, H-6), 4.39 (q, J=2.7 Hz, 1H, H-5), 4.32 (dd, J=12.2, 2.2 Hz, 1H, H-6″), 4.25-4.19 (m, 2H, H-6″, H-5′), 4.01 (ddd, J=12.3, 10.4, 4.7 Hz, 1H, H-1), 3.92 (ddd, J=12.4, 9.9, 4.9 Hz, 1H, H-3), 3.77 (dd, J=7.3, 5.0 Hz, 1H, H-7′), 3.72 (ddd, J=10.6, 5.3, 2.2 Hz, 1H, H-5″), 3.67 (td, J=10.9, 4.4 Hz, 1H, H-4′), 3.61 (dd, J=9.9, 2.7 Hz, 1H, H-4), 3.57 (t, J=10.2 Hz, 1H, H-4″), 3.45 (dt, J=12.6, 4.1 Hz, 1H, H-2′), 3.13 (d, J=2.7 Hz, 1H, OH), 2.94 (s, 3H, NCH.sub.3), 2.36-2.26 (m, 2H, H-2, H-3′), 2.16 (s, 3H, COCH.sub.3), 2.15-2.05 (m, 6H, 2*COCH.sub.3), 1.99 (dd, J=23.9, 12.0 Hz, 1H, H-3′), 1.33 (q, J=12.7 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.4 (C═O), 170.2 (C═O), 169.7 (C═O), 157.1 (C═O), 98.0 (C-8′), 94.5 (C-1′), 94.2 (C-1″), 78.6 (C-4), 74.8 (C-6), 71.3 (C-6′), 70.1 (C-2″), 69.9 (C-3″), 69.3 (C-5″), 66.7 (C-5), 66.6 (C-5′), 65.6 (C-4′), 62.8 (C-6″), 60.2 (C-7′), 60.1 (C-4″), 57.15 (C-3), 57.07 (C-2′), 55.7 (C-1), 32.0 (C-2), 30.2 (NCH.sub.3), 29.4 (C-3′), 20.9 (COCH.sub.3), 20.7 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.30H.sub.39N.sub.13NaO.sub.16 [M+Na].sup.+ 860.2535; found, 860.2530.

(53) 6,2″,3″,6″-Tetra-O-acetyl-1,3,2′,4″-tetraazido-5-deoxy-5-fluoro-6′, 7′-oxazolidino-apramycin (I). A stirred ice-cooled solution of compound k (36 mg, 0.04 mmol) in dry DCM (0.2 mL), was treated with diethylaminosulfur trifluoride (45 μL, 0.34 mmol) and stirred at 0° C. for 1 h and at rt for 30 min. After completion, the reaction mixture was purified by gradient chromatography over silica gel (eluent: 0.7% to 0.8% MeOH in DCM) to give I (29 mg, 81%) as a white solid; [α].sub.D.sup.25=+127.76 (c 1.9, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 5.40 (t, J=10.0 Hz, 1H, H-3″), 5.35 (d, J=3.8 Hz, 1H, H-1″), 5.21-5.07 (m, 2H, H-6, H-1′), 4.96-4.86 (m, 2H, H-8′, H-2″), 4.82 (dd, J=8.2, 3.4 Hz, 1H, H-6′), 4.57 (dd, J=10.4, 3.3 Hz, 1H, H-5′), 4.45 (dt, J=50.3, 9.1 Hz, 1H, H-5), 4.34 (dd, J=12.2, 2.4 Hz, 1H, H-6″), 4.23 (dd, J=12.2, 5.1 Hz, 1H, H-6″), 3.86-3.66 (m, 5H, H-3, H-4, H-4′, H-7′, H-5″), 3.65-3.58 (m, 1H, H-4″), 3.53 (ddd, J=12.3, 10.2, 4.4 Hz, 1H, H-1), 3.30 (dt, J=12.9, 4.1 Hz, 1H, H-2′), 2.94 (s, 3H, NCH.sub.3), 2.47 (dt, J=13.2, 4.4 Hz, 1H, H-2), 2.27 (dt, J=11.4, 4.4 Hz, 1H, H-3′), 2.20-2.06 (m, 12H, 4*COCH.sub.3), 1.94 (q, J=11.5 Hz, 1H, H-3′), 1.67 (q, J=12.5 Hz, 1H, H-2); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 170.3 (C═O), 170.0 (C═O), 169.9 (C═O), 169.5 (C═O), 156.9 (C═O), 98.6 (C-1′), 96.1 (C-8′), 94.6 (C-1″), 93.34 (d, J=187.8 Hz, C-5), 79.78 (d, J=17.1 Hz, C-4), 73.05 (d, J=18.5 Hz, C-6), 70.6 (C-3″), 70.2 (C-2″), 70.0 (C-6′), 69.0 (C-5″), 65.8 (C-5′), 65.4 (C-4′), 62.8 (C-6″), 60.2 (C-7′), 60.1 (C-4″), 57.58 (d, J=10.6 Hz, C-3), 57.00 (d, J=9.3 Hz, C-1), 56.4 (C-2′), 31.7 (C-2), 30.0 (NCH.sub.3), 29.7 (C-3′), 20.9 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3), 20.7 (COCH.sub.3);.sup.19F NMR (376 MHz, CDCl3): δ−196.30 (dt, J=50.4, 11.5 Hz); ESI-HRMS: m/z calcd. for C.sub.30H.sub.38FN.sub.13NaO.sub.15 [M+Na].sup.+ 862.2492; found, 862.2511.

(54) 5-Deoxy-5-fluoro apramycin pentaacetate salt (DCWSU170). A stirred solution of compound 1 (29 mg, 0.035 mmol) in dioxane (0.2 mL) was treated with 3N NaOH (0.2 mL) and heated at 100° C. for 2 h. 1M P(CH.sub.3).sub.3 in THF (0.3 mL) was added and the reaction mixture was stirred at 55° C. for 2 h. The reaction mixture was then concentrated and dissolved in aqueous acetic acid solution (pH 4, 1 mL) then charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid, and lyophilized to afford DCWSU170 (16 mg, 56%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+89.91 (c 1.1, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.35 (d, J=3.4 Hz, 1H, H-1′), 5.28 (d, J=3.8 Hz, 1H, H-1″), 5.00 (d, J=8.5 Hz, 1H, H-8′), 4.43 (dt, J=50.8, 9.0 Hz, 1H, H-5), 4.35 (s, 1H, H-6′), 4.04 (q, J=9.6 Hz, 1H, H-4), 3.79-3.69 (m, 4H, H-6, H-4′, H-3″, H-5″), 3.63 (dd, J=12.3, 2.9 Hz, 1H, H-6″), 3.56 (dd, J=12.5, 4.5 Hz, 1H, H-6″), 3.52 (d, J=10.3 Hz, 1H, H-5′), 3.49 (dd, J=9.8, 3.9 Hz, 1H, H-2″), 3.44 (dt, J=12.3, 3.9 Hz, 1H, H-2′), 3.34 (td, J=11.7, 10.9, 4.0 Hz, 1H, H-3), 3.21-3.14 (m, 2H, H-1, H-7′), 3.07 (t, J=10.4 Hz, 1H, H-4″), 2.57 (s, 3H, NCH.sub.3), 2.29 (dt, J=12.8, 4.3 Hz, 1H, H-2), 2.15 (dt, J=10.1, 4.5 Hz, 1H, H-3′), 1.87-1.83 (m, 1H, H-3′), 1.73-1.66 (m, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 95.33 (d, J=190.2 Hz, C-5), 94.8 (C-1′), 94.3 (C-1″), 92.7 (C-8′), 75.72 (d, J=16.8 Hz, C-4), 70.27 (d, J=20.5 Hz, C-6), 70.2 (C-2″), 69.5 (C-5′), 69.3 (C-5″), 68.2 (C-3″), 65.8 (C-4′), 62.6 (C-6′), 60.2 (C-6″), 59.3 (C-7′), 52.0 (C-4″), 48.67 (d, J=11.5 Hz, C-1), 47.6 (C-2′), 47.34 (d, J=11.3 Hz, C-3), 29.9 (NCH.sub.3), 28.0 (C-2), 26.6 (C-3′)..sup.19F NMR (376 MHz, D.sub.2O): δ −195.08 (dt, J=50.9, 11.7 Hz); ESI-HRMS: m/z calcd. for C.sub.21H.sub.41FN.sub.5O.sub.10 [M+H].sup.+ 542.2837; found, 542.2838.

(55) 6,2″,3″,6″-Tetra-O-acetyl-1,3,2′,4″-tetraazido-5-deoxy-5-epifluoro-6′,7′-oxazolidino-apramycin (m). To a stirred ice-cooled solution of compound 124 (50 mg, 0.06 mmol) in dry DCM (0.2 mL), diethylaminosulfur trifluoride (65 μl, 0.48 mmol) was added, and the reaction mixture was stirred at rt for 3 h. After completion, the reaction mixture was purified by gradient chromatography over silica gel (eluent: 0.7% to 0.8% MeOH in DCM) to give m (37 mg, 74%) as a white solid; [α].sub.D.sup.25=+104.39 (c 2.5, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 5.42 (t, J=10.0 Hz, 1H, H-3″), 5.38 (d, J=3.8 Hz, 1H, H-1″), 5.09-4.96 (m, 2H, H-5, H-1′), 4.90-4.84 (m, 2H, H-8′, H-2″), 4.80 (dd, J=7.7, 3.5 Hz, 1H, H-6′), 4.70 (ddd, J=27.3, 10.5, 1.8 Hz, 1H, H-6), 4.35 (dd, J=10.4, 3.4 Hz, 1H, H-5′), 4.32 (dd, J=12.2, 2.2 Hz, 1H, H-6″), 4.21 (dd, J=12.2, 5.3 Hz, 1H, H-6″), 4.02-3.92 (m, 2H, H-1, H-3), 3.80 (dd, J=7.6, 4.3 Hz, 1H, H-7′), 3.78-3.69 (m, 2H, H-4′, H-5″), 3.67-3.55 (m, 2H, H-4, H-4″), 3.34 (dt, J=12.8, 4.0 Hz, 1H, H-2′), 2.94 (s, 3H, NCH.sub.3), 2.45 (dt, J=13.5, 4.9 Hz, 1H, H-2), 2.29 (dt, J=11.3, 4.4 Hz, 1H, H-3′), 2.17 (s, 3H, COCH.sub.3), 2.10 (d, J=10.8 Hz, 6H, 2*COCH.sub.3), 2.06 (s, 3H, COCH.sub.3), 2.01-1.94 (m, 1H, H-3′), 1.42 (q, J=12.7 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.4 (C═O), 169.9 (C═O), 169.7 (C═O), 156.9 (C═O), 96.7 (C-8′), 96.2 (C-1′), 94.1 (C-1″), 87.65 (d, J=184.1 Hz, C-5), 77.55 (d, J=17.9 Hz, C-4), 73.45 (d, J=17.1 Hz, C-6), 70.6 (C-6′), 70.3 (C-3″), 69.8 (C-2″), 69.1 (C-5″), 66.4 (C-5′), 65.5 (C-4′), 62.9 (C-6″), 60.2 (C-4″), 60.0 (C-7′), 57.03 (d, J=3.8 Hz, C-3), 56.0 (C-2′), 55.76 (d, J=4.1 Hz, C-1), 32.0 (C-2), 30.1 (NCH.sub.3), 29.2 (C-3′), 20.7 (COCH.sub.3), 20.7 (COCH.sub.3), 20.7 (COCH.sub.3);.sup.19F NMR (376 MHz, CDCl.sub.3): δ −213.48 (dt, J=52.6, 26.8 Hz); ESI-HRMS: m/z calcd. for C.sub.30H.sub.38FN.sub.13NaO.sub.15 [M+Na].sup.+ 862.2492; found, 862.2502.

(56) 5-Deoxy-5-epi-fluoro apramycin pentaacetate salt (DCWSU168). A stirred solution of compound m (37 mg, 0.044 mmol) in dioxane (0.2 mL) was treated with 3 N NaOH (0.2 mL) and heated at 100° C. for 2 h. 1 M P(CH.sub.3).sub.3 in THF (0.3 mL) was added and the reaction mixture stirred at 55° C. for 2h. The reaction mixture was then concentrated and dissolved in aqueous acetic acid solution (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid, and lyophilized to afford DCWSU168 (22 mg, 59%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+152.0 (c 0.1, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.25 (d, J=3.9 Hz, 1H, H-1″), 5.24 (d, J=3.8 Hz, 1H, H-1′), 5.13 (d, J=51.7 Hz, 1H, H-5), 4.98 (d, J=8.5 Hz, 1H, H-8′), 4.31 (s, 1H, H-6′), 3.94 (dd, J=26.1, 10.7 Hz, 1H, H-4), 3.78-3.63 (m, 4H, H-6, H-4′, H-3″, H-5″), 3.61 (dd, J=12.5, 3.5 Hz, 1H, H-6″), 3.57-3.50 (m, 2H, H-3, H-6″), 3.49-3.44 (m, 2H, H-2′, H-2″), 3.42 (dd, J=10.1, 2.6 Hz, 1H, H-5′), 3.33 (td, J=11.7, 4.3 Hz, 1H, H-1), 3.12 (dd, J=8.5, 2.8 Hz, 1H, H-7′), 3.05 (t, J=10.4 Hz, 1H, H-4″), 2.54 (s, 3H, NCH.sub.3), 2.29 (dt, J=12.6, 4.4 Hz, 1H, H-2), 2.19-2.10 (m, 1H, H-3′), 1.90-1.82 (m, 1H, H-3′), 1.59 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 94.3 (C-1″), 92.7 (C-8′), 90.3 (C-1′), 87.37 (d, J=181.7 Hz, C-5), 72.01 (d, J=17.8 Hz, C-4), 70.1 (C-2″), 69.5 (C-5′), 69.2 (C-5″), 68.55 (d, J=17.2 Hz, C-6), 68.1 (C-3″), 65.7 (C-4′), 62.5 (C-6′), 60.2 (C-6″), 59.3 (C-7′), 52.0 (C-4″), 48.09 (d, J=4.4 Hz, C-1), 47.3 (C-2′), 46.61 (d, J=4.2 Hz, C-3), 29.9 (NCH.sub.3), 27.9 (C-2), 26.7 (C-3′); .sup.19F NMR (376 MHz, D.sub.2O): δ −217.88 (dt, J=51.8, 27.2 Hz); ESI-HRMS: m/z calcd. for C.sub.21H.sub.41FN.sub.5O.sub.10 [M+H].sup.+ 542.2837; found, 542.2825.

(57) 6,2″,3″,6″-Tetra-O-acetyl-1,3,2′,4″-tetraazido-5-deoxy-5-epiiodo-6′,7′-oxazolidino-apramycin (n). To a stirred solution of compound A (100 mg, 0.12 mmol) in dry DCM (1.5 mL), pyridine (0.1 mL) was added and reaction mixture was cooled to 0° C. before triflic anhydride (40 μL, 0.24 mmol) was added. The reaction mixture was stirred for 1 h and additional triflic anhydride (40 μL, 0.24 mmol) was added. After 2 h, the reaction mixture was poured into an iced aqueous solution of NaHCO.sub.3 and extracted with EtOAc. The organic layer was washed with brine and dried over Na.sub.2SO.sub.4 and concentrated in vacuo. The crude product was dissolved in dry acetone (25 mL), heated to reflux under stirring with sodium iodide (266 mg, 1.78 mmol) for 12 h. After completion, the reaction mixture was concentrated, diluted with EtOAc and washed with brine then concentrated. The crude product was purified using silica gel column chromatography (eluent: 0.6%-1.0% Methanol/DCM) to give compound n (93 mg, 89%) as a white solid; [α].sub.D.sup.25=+172.23 (c 6.2, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 5.46-5.38 (m, 2H, H-1″, H-3″), 4.92 (d, J=3.4 Hz, 1H, H-1′), 4.84 (t, J=3.2 Hz, 1H, H-5), 4.80-4.72 (m, 3H, H-6′, H-8′, H-2″), 4.31 (dd, J=12.3. 2.2 Hz. 1H. H-6″), 4.20 (dd, J=12.2, 5.4 Hz, 1H, H-6″), 4.04-3.98 (m, 2H, H-3, H-4), 3.98-3.90 (m, 2H, H-1, H-5′), 3.80-3.70 (m, 2H, H-7′, H-5″), 3.66 (td, J=10.8, 4.5 Hz, 1H, H-4′), 3.55 (t, J=10.2 Hz, 1H, H-4″), 3.25 (dt, J=12.8, 3.9 Hz, 1H, H-2′), 3.06 (dd, J=9.7, 3.6 Hz, 1H, H-6), 2.94 (s, 3H, NCH.sub.3), 2.28 (ddt, J=12.6, 8.7, 4.6 Hz, 2H, H-2, H-3′), 2.15 (s, 3H, COCH.sub.3), 2.13-2.03 (m, 7H, H-3′,2*COCH.sub.3), 2.01 (s, 3H, COCH.sub.3), 1.41-1.29 (m, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.4 (C═O), 170.2 (C═O), 169.6 (C═O), 169.6 (C═O), 156.8 (C═O), 99.8 (C-8′), 94.3 (C-1″), 93.9 (C-1′), 74.1 (C-6), 72.6 (C-4), 71.7 (C-6′), 69.9 (C-2″), 69.8 (C-3″), 69.4 (C-5″), 67.2 (C-5′), 65.8 (C-4′), 62.8 (C-6″), 60.6 (C-1), 60.2 (C-4″), 60.1 (C-7′), 59.2 (C-3), 55.4 (C-2′), 32.8 (C-5), 32.6 (C-2), 30.4 (NCH.sub.3), 28.0 (C-3′), 20.9 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.30H.sub.36IN.sub.13NaO.sub.15 [M+Na].sup.+ 970.1553; found, 970.1571.

(58) 5-Deoxy-apramycin pentaacetate salt (DCWSU169). To a solution of compound n (45 mg, 0.05 mmol) in dry methanol (5 mL), sodium methoxide (10 mg, 0.06 mmol) was added and the reaction mixture was stirred for 30 min. The reaction was quenched with Amberlyst®, filtered and the solvent was evaporated in vacuo. The crude product was dissolved in dioxane:water:glacial acetic acid=1:2:0.2 (0.3 mL) and 10% Pd/C (60 mg, 1.1 equiv.) was added. The reaction was stirred at room temperature under 1 atm of hydrogen (balloon) for 12 h. After completion, the reaction mixture was filtered over Celite® and filtrate concentrated to dryness. The residue was dissolved in dioxane (0.5 mL) and treated with 3N NaOH (0.25 mL) and heated at 100° C. for 30 min. The reaction mixture was cooled to rt and neutralized with glacial acetic acid before concentration in vacuo. The crude product was dissolved in aqueous acetic acid solution (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid and lyophilized to afford the peracetate salt of DCWSU169 (18.5 mg, 47%) as a white solid; [α].sub.D.sup.25=+105.0 (c 0.2, H.sub.2O); 1H NMR (600 MHz, D.sub.2O): δ 5.35 (d, J=4.0 Hz, 1H, H-1″), 5.23 (d, J=3.8 Hz, 1H, H-1′), 5.07 (d, J=8.5 Hz, 1H, H-8′), 4.40 (s, 1H, H-6′), 3.87-3.73 (m, 4H, H-4, H-4′, H-3″, H-5″), 3.70 (dd, J=12.5, 3.3 Hz, 1H, H-6″), 3.63 (dd, J=12.5, 4.7 Hz, 1H, H-6″), 3.62-3.52 (m, 2H, H-6, H-2″), 3.52 (dt, J=12.8, 4.3 Hz, 1H, H-2′), 3.48 (dd, J=10.0, 3.0 Hz, 1H, H-5′), 3.34 (ddd, J=12.4, 10.1, 4.1 Hz, 1H, H-3), 3.21 (dd, J=8.5, 2.9 Hz, 1H, H-7′), 3.17-3.10 (m, 2H, H-1, H-4″), 2.63 (s, 3H, NCH.sub.3), 2.55 (dt, J=12.2, 4.3 Hz, 1H, H-5), 2.33 (dt, J=12.6, 4.3 Hz, 1H, H-2), 2.23 (dt, J=10.8, 4.5 Hz, 1H, H-3′), 1.90 (q, J=11.8, 11.0 Hz, 1H, H-3′), 1.61 (q, J=12.5 Hz, 1H, H-2), 1.34 (q, J=11.7 Hz, 1H, H-5); .sup.13C NMR (151 MHz, D.sub.2O): δ 94.3 (C-1″), 92.7 (C-8′), 90.1 (C-1′), 70.8 (C-4), 70.2 (C-6), 69.4 (C-2″), 69.3 (C-5′), 68.2 (C-5″), 67.2 (C-3″), 65.8 (C-4′), 62.6 (C-6′), 60.2 (C-6″), 59.4 (C-7′), 52.5 (C-1), 52.0 (C-4″), 50.8 (C-3), 47.3 (C-2′), 33.8 (C-5), 30.0 (NCH.sub.3), 28.5 (C-2), 26.9 (C-3′); ESI-HRMS: m/z calcd. for C.sub.21H.sub.42N.sub.5O.sub.10 [M+H].sup.+ 524.2932; found, 524.2924.

Example 8

DCWSU 164 and 167

(59) See the synthetic scheme of FIG. 16. Note intermediates AK-1 and AK-2 are not drawn in the scheme for these two compounds 5,2″,3″,6″-Tetra-O-acetyl-6-O-allyl-1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin (AK). 6,2″,3″,6″-Tetra-O-acetyl-1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin A (100 mg, 0.12 mmol) was dissolved in dry DCM (0.5 mL) and treated with allyl bromide (0.5 mL, 5.9 mmol) and silver oxide (400 mg, 1.7 mmol). The reaction mixture was covered with aluminium foil and stirred at rt for 12 h. After completion, the reaction was filtered through Celite® and concentrated to dryness. The crude product was purified by column chromatography (eluent: 5% to 30% EtOAc/hexanes) to give AK (60 mg, 59%) as a white solid; [α].sub.D.sup.25=+60.0 (c 0.2, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 5.86 (ddt, J=16.3, 10.3, 5.9 Hz, 1H, CH.sub.2CHCH.sub.2O), 5.45-5.34 (m, 1H, H-3″), 5.32 (d, J=3.8 Hz, 1H, H-1″), 5.25 (dd, J=17.2, 1.5 Hz, 1H, CH.sub.2CHCH.sub.2O), 5.22-5.16 (m, 1H, CH.sub.2CHCH.sub.2O), 5.05 (t, J=9.9 Hz, 1H, H-5), 4.99-4.90 (m, 2H, H-8′, H-2″), 4.87 (d, J=3.6 Hz, 1H, H-1′), 4.81 (dd, J=8.6, 3.2 Hz, 1H, H-6′), 4.74 (dd, J=10.5, 3.2 Hz, 1H, H-5′), 4.36-4.17 (m, 3H, H-6″, CH.sub.2CHCH.sub.2O), 4.09 (dd, J=12.2, 6.1 Hz, 1H, CH.sub.2CHCH.sub.2O), 3.92-3.82 (m, 2H, H-4′, H-7′), 3.82-3.76 (m, 1H, H-3), 3.76-3.67 (m, 1H, H-5″), 3.66-3.52 (m, 2H, H-1, H-4″), 3.48 (t, J=9.9 Hz, 1H, H-4), 3.39 (dt, J=12.7, 4.1 Hz, 1H, H-2′), 3.19 (t, J=9.8 Hz, 1H, H-6), 2.92 (s, 3H, NCH.sub.3), 2.46 (dt, J=13.1, 4.6 Hz, 1H, H-2), 2.26 (dt, J=10.7, 4.1 Hz, 1H, H-3′), 2.21-2.02 (m, 12H, 4*C0CH.sub.3), 1.85 (q, J=11.4 Hz, 1H, H-3′), 1.49 (q, J=12.5 Hz, 1H, H-2); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 170.3 (C═O), 170.3 (C═O), 170.0 (C═O), 169.4 (C═O), 156.9 (C═O), 133.6 (CH.sub.2CHCH.sub.2O), 118.1 (CH.sub.2CHCH.sub.2O), 99.1 (C-1′), 94.2 (C-8′, C-1″), 81.9 (C-6), 80.3 (C-4), 74.3 (CH.sub.2CHCH.sub.2O), 74.0 (C-5), 70.7 (C-3″), 69.9 (C-2″), 69.7 (C-6′), 68.8 (C-5″), 65.4 (C-5′), 65.2 (C-4′), 62.9 (C-6″), 60.2 (C-4″), 60.0 (C-7′), 59.7 (C-1), 58.4 (C-3), 56.6 (C-2′), 32.1 (C-2), 30.0 (NCH.sub.3), 29.8 (C-3′), 21.1 (COCH.sub.3), 21.0 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.33H.sub.43N.sub.13NaO.sub.16 [M+Na].sup.+ 900.2848; found, 900.2841.

(60) 5,2″,3″,6″-Tetra-O-acetyl-1,3,2′,4″-tetraazido-6-O—(2,3-dihydroxypropyl)-6′,7′-oxazolidino-apramycin (AK-1). A stirred solution of compound AK (20 mg, 0.02 mmol) in THF (0.4 mL) and water (0.1 mL) was treated with N-methylmorpholine-N-oxide (8 mg, 0.07 mmol) and 2.5% OsO.sub.4 in tert-butanol (60 μL mg, 0.005 mmol). The reaction mixture was stirred at rt for 4 h. After completion, the reaction mixture was diluted with EtOAc and the organic layer was washed with aqueous NaHCO.sub.3 followed by brine, dried with Na.sub.2SO.sub.4, and concentrated. The crude product was purified via silica gel chromatography eluting with 0.7% to 3% methanol in DCM to give AK-1 (15 mg, 71%) as a white solid; [α].sub.D.sup.25=+63.75 (c 1.3, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 5.38 (t, J=9.9 Hz, 1H, H-3′), 5.32 (d, J=3.8 Hz, 1H, H-1″), 5.08-5.01 (m, 1H, H-5), 4.98-4.91 (m, 2H, H-8′, H-2″), 4.88 (d, J=3.0 Hz, 1H, H-1′), 4.80 (dd, J=8.6, 3.1 Hz, 1H H-6′), 4.71 (dd, J=10.5, 3.1 Hz, 1H, H-5′), 4.36-4.27 (m, 1H, H-6″), 4.22 (dd, J=12.2, 5.0 Hz, 1H, H-6″), 3.90-3.68 (m, 6H, H-3, H-4′, H-7′, H-5″, CH.sub.2OHCHOHCH.sub.2O, CH.sub.2OHCHOHCH.sub.2O), 3.66-3.43 (m, 6H, H-1, H-4, H-4″, CH.sub.2OHCHOHCH.sub.2O, CH.sub.2OHCHOHCH.sub.2O), 3.37 (dt, J=12.6, 3.6 Hz, 1H, H-2′), 3.19 (t, J=9.8 Hz, 1H, H-6), 2.91 (s, 3H, NCH.sub.3), 2.48 (dt, J=12.7, 4.2 Hz, 1H, H-2), 2.29-2.23 (m, 1H, H-3′), 2.17-2.07 (m, 12H, 4*C0CH.sub.3), 1.90-1.80 (m, 1H, H-3′), 1.59-1.46 (m, 1H, H-2); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 170.4 (C═O), 170.2 (C═O), 170.0 (C═O), 157.0 (C═O), 99.1 (C-1′), 94.5 (C-8′), 94.3 (C-1″), 82.9 (C-6), 80.0 (C-4), 74.8 (C-5), 74.4 (CH.sub.2OHCHOHCH.sub.2O), 70.7 (C-3″), 70.6 (C-2″), 69.9 (CH.sub.2OHCHOHCH.sub.2O), 69.7 (C-6′), 68.8 (C-5″), 65.4 (C-5′), 65.2 (C-4′), 63.1 (CH.sub.2OHCHOHCH.sub.2O), 62.9 (C-6″), 60.1 (C-4″), 60.0 (C-7′), 59.6 (C-1), 58.2 (C-3), 56.4 (C-2′), 31.8 (C-2), 29.9 (NCH.sub.3), 29.8 (C-3′), 21.1 (COCH.sub.3), 20.9 (COCH.sub.3), 20.9 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.33H.sub.45N.sub.13NaO.sub.18 [M+Na].sup.+ 934.2903; found, 934.2905.

(61) 6-O—(2,3-Dihydroxypropyl)-apramycin pentaacetate salt (DCWSU164). A stirred solution of compound AK-1 (14 mg, 0.015 mmol) in dioxane (0.2 mL) was treated with 3N NaOH (0.2 mL) and heated at 100° C. for 2 h. 1M P(CH.sub.3).sub.3 in THF (0.15 mL) was added and the reaction mixture was stirred at 55° C. for 2 h. The reaction mixture was cooled to 0° C., neutralized with glacial acetic acid and concentrated. The crude product was dissolved in aqueous acetic acid solution (pH 4, 1 mL) then charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid, and lyophilized to afford DCWSU164 (5.5 mg, 39%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+100.96 (c 0.2, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.51 (s, 1H, H-1′), 5.28 (d, J=4.0 Hz, 1H, H-1″), 5.00 (dd, J=8.4, 1.5 Hz, 1H, H-8′), 4.35 (s, 1H, H-6′), 3.86-3.66 (m, 6H, H-4, H-4′, H-3″, H-5″, CH.sub.2OHCHOHCH.sub.2O, CH.sub.2OHCHOHCH.sub.2O), 3.66-3.52 (m, 5H, H-5, H-5′, H-6″, CH.sub.2OHCHOHCH.sub.2O), 3.50 (dd, J=9.3, 3.9 Hz, 1 H, H-2″), 3.48-3.34 (m, 4H, H-2′, CH.sub.2OHCHOHCH.sub.2O), 3.32-3.22 (m, 2H, H-3, H-6), 3.23-3.14 (m, 2H, H-1, H-7′), 3.08 (t, J=10.2 Hz, 1H, H-4″), 2.57 (s, 3H, NCH.sub.3), 2.31-2.23 (m, 1H, H-2), 2.19-2.10 (m, 1H, H-3′), 1.66 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O) δ 95.4 (C-1′), 94.3 (C-1″), 92.7 (C-8′), 81.3 (C-6), 77.7 (C-4), 75.2 (C-5), 73.7 (CH.sub.2OHCHOHCH.sub.2O), 70.3 (CH.sub.2OHCHOHCH.sub.2O), 70.1 (C-2″), 69.6 (C-5′), 69.2 (C-5″), 68.2 (C-3″), 65.9 (C-4′), 62.6 (C-6′), 62.1 (CH.sub.2OHCHOHCH.sub.2O), 60.2 (C-6″), 59.3 (C-7′), 52.0 (C-4″), 48.8 (C-1), 48.2 (C-3), 47.8 (C-2′), 29.9 (NCH.sub.3), 28.1 (C-2), 26.6 (C-3′); ESI-HRMS: m/z calcd. for C.sub.24H.sub.48N.sub.5O.sub.13 [M+H].sup.+ 614.3249; found, 614.3242.

(62) 5,2″,3″,6″-Tetra-O-acetyl-1,3,2′,4″-tetraazido-6-O-(2-hydroxyethyl)-6′,7′-oxazolidino-apramycin (AK-2). To a stirred solution of compound AK-1 (22 mg, 0.024 mmol) in THF (0.4 mL) and water (0.1 mL), NalO.sub.4 (15.5 mg, 0.07 mmol) was added and the reaction mixture was stirred at rt for 12 h. The reaction mixture was diluted with EtOAc and washed with aqueous NaHCO.sub.3 and brine. The organic layer was dried over Na.sub.2SO.sub.4 and concentrated. To a solution of the residue in in THF (0.4 mL) and water (0.1 mL), NaBH.sub.4 (1.8 mg, 0.048 mmol) and the reaction mixture was stirred at rt for 45 min. The reaction mixture was diluted with EtOAc and washed with aqueous NaHCO.sub.3, brine, dried with Na.sub.2SO.sub.4 and concentrated. The crude product was purified using silica gel column chromatography (eluent: 0.75%-3% methanol/DCM) to give AK-2 (11 g, 52%) as a white solid; [α].sub.D.sup.25=+60.6 (c 0.3, DCM);.sup.1H NMR (600 MHz, CD.sub.3OD): δ 5.47-5.40 (m, 1H, H-3″), 5.38 (d, J=3.8 Hz, 1H, H-1″), 5.13 (d, J=2.1 Hz, 1H, H-8′), 5.02 (t, J=9.7 Hz, 1H, H-5), 4.97 (dd, J=10.3, 3.8 Hz, 1H, H-2″), 4.92-4.86 (m, 3H, H-1′, H-5′, H-6′), 4.35 (d, J=12.1 Hz, 1H, H-6″), 4.25 (dd, J=12.3, 4.1 Hz, 1H, H-6″), 4.10 (dd, J=8.9, 2.1 Hz, 1H, H-7′), 3.89-3.79 (m, 4H, H-4′, H-4″, H-5″, CH.sub.2OHCH.sub.2O), 3.79-3.73 (m, 1H, H-3), 3.72-3.63 (m, 2H, H-4, CH.sub.2OHCH.sub.2O), 3.63-3.54 (m, 3H, H-1, CH.sub.2OHCH.sub.2O), 3.57-3.49 (m, 1H, H-2′), 3.37 (t, J=9.8 Hz, 1H, H-6), 2.91 (s, 3H, NCH.sub.3), 2.44 (dt, J=12.7, 4.6 Hz, 1H, H-2), 2.28 (dt, J=8.8, 4.2 Hz, 1H, H-3′), 2.18-2.04 (m, 12H, 4*COCH.sub.3), 1.85-1.79 (m, 1H, H-3′), 1.61 (q, J=12.5 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CD.sub.3OD): δ 170.9 (C═O), 170.5 (C═O), 170.4 (C═O), 158.2 (C═O), 99.1 (C-1′), 93.9 (C-1″), 93.0 (C-8′), 82.5 (C-6), 80.2 (C-4), 74.5 (C-5), 74.1 (CH.sub.2OHCH.sub.2O), 70.9 (C-3″), 70.2 (C-2″), 70.0 (C-6′), 68.7 (C-5″), 65.1 (C-5′), 65.1 (C-4′), 62.9 (C-6″), 60.8 (CH.sub.2OHCH.sub.2O), 60.1 (C-4″), 59.9 (C-7′), 59.8 (C-1), 58.2 (C-3), 56.6 (C-2′), 31.1 (C-2), 30.1 (C-3′), 28.6 (NCH.sub.3), 20.1 (COCH.sub.3), 20.0 (COCH.sub.3), 19.4 (COCH.sub.3), 19.2 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.32H.sub.43N.sub.13NaO.sub.17 [M+Na].sup.+904.2798; found, 904.2801.

(63) 6-O-(2-Hydroxyethyl)-apramycin pentaacetate salt (DCWSU167). A stirred solution of compound 176 (10 mg, 0.011 mmol) in dioxane (0.2 mL) was treated with 3N NaOH (0.2 mL) and heated at 100° C. for 1 h. 1M P(CH.sub.3).sub.3 in THF (0.15 mL) was added and the reaction mixture was stirred at 55° C. for 2 h. The reaction mixture was cooled to 0° C., neutralized with glacial acetic acid and concentrated. The crude product was dissolved in aqueous acetic acid solution (pH 4, 1 mL) then charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid, and lyophilized to afford DCWSU167 (6.3 mg, 63%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+107.38 (c 0.4, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.52 (d, J=3.8 Hz, 1H, H-1′), 5.32 (d, J=4.0 Hz, 1H, H-1″), 5.04 (d, J=8.5 Hz, 1H, H-8′), 4.38 (s, 1H, H-6′), 3.90-3.84 (m, 1H, CH.sub.2OHCH.sub.2O), 3.80-3.66 (m, 5H, H-4, H-4′, H-3″, H-5″, H-6″), 3.66-3.55 (m, 6H, H-5, H-5′, H-6″, CH.sub.2OHCH.sub.2O, CH.sub.2OHCH.sub.2O), 3.54 (dd, J=9.7, 4.0 Hz, 1H, H-2″), 3.47 (dt, J=13.0, 4.1 Hz, 1H, H-2′), 3.33 (t, J=9.7 Hz, 1H, H-6), 3.27-3.15 (m, 3H, H-1, H-3, H-7′), 3.08 (t, J=10.3 Hz, 1H, H-4″), 2.61 (s, 3H, NCH.sub.3), 2.31-2.24 (m, 1H, H-2), 2.20 (dt, J=8.7, 3.9 Hz, 1H, H-3′), 1.86 (q, J=11.6 Hz, 1H, H-3′), 1.64 (q, J=11.7, 11.0 Hz, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 95.6 (C-1′), 94.4 (C-1″), 92.9 (C-8′), 81.5 (C-6), 79.0 (C-4), 75.3 (C-5), 74.0 (CH.sub.2OHCH.sub.2O), 70.2 (C-2″), 69.7 (C-5′), 69.6 (C-5″), 68.6 (C-3″), 66.0 (C-4′), 62.8 (C-6′), 60.8 (CH.sub.2OHCH.sub.2O), 60.3 (C-6″), 59.4 (C-7′), 52.0 (C-4″), 49.1 (C-1), 48.3 (C-3), 47.9 (C-2′), 30.0 (NCH.sub.3), 28.9 (C-2), 26.8 (C-3′); ESI-HRMS: m/z calcd. for C.sub.24H.sub.48N.sub.5O.sub.13 [M+H].sup.+ 584.3143; found, 584.3129.

Example 9

DCWSU177

(64) See the synthetic scheme of FIG. 5.

(65) 1,2,3-Tri-O-acetyl-5-deoxy-5-phthalimido-α-D-ribofuranose (I). 1,2,3-Tri-O-acetyl-5-O-p-tolylsulfonyl-D-ribofuranose H (1.00 g, 2.3 mmol) was dissolved in dry DMF (20 mL) and treated with potassium phthalimide (1.00 g, 5.4 mmol). The reaction mixture was stirred at 50° C. for 12 h before it was diluted with water and extracted with DCM three times. The organic layer wash then washed with 5% aqueous NaOH and brine, dried over Na.sub.2SO.sub.4, and concentrated. The residue was purified using silica gel column chromatography (eluent: 15% −35% EtOAc/hexanes) to give I (566 mg, 60%) as a white solid; [α].sub.D.sup.25=+49.66 (c 1.3, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.80-7.73 (m, 2H, ArH), 7.70-7.62 (dd, J=5.4, 3.1 Hz, 2H, ArH), 6.34 (d, J=4.5 Hz, 1H, H-1), 5.23 (dd, J=6.8, 4.5 Hz, 1H, H-2), 5.15 (dd, J=6.7, 3.4 Hz, 1H, H-3), 4.48 (td, J=6.8, 3.4 Hz, 1H, H-4), 3.86 (dd, J=6.8, 5.2 Hz, 2H, H-5), 2.03-1.95 (m, 9H, COCH.sub.3);.sup.13C NMR (101 MHz, CDCl.sub.3): δ 169.9 (C═O), 169.4 (C═O), 169.2 (C═O), 168.0 (C═O), 134.1 (ArC), 131.8 (ArC), 123.4 (ArC), 93.7 (C-1), 80.4 (C-4), 70.7 (C-3), 69.6 (C-2), 39.3 (C-5), 20.9 (COCH.sub.3), 20.5 (COCH.sub.3), 20.2 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.19H.sub.19NNaO.sub.9 [M+Na].sup.+ 428.0958; found, 428.0964.

(66) 2,3-Di-O-acetyl-5-deoxy-5-phthalimido-D-ribofuranosyl trichloroacetimidate (J). To an ice-cooled solution of I (550 mg, 1.36 mmol) in DCM (5 mL), 33% HBr/acetic acid (0.7 mL, 4.07 mmol) was added followed by stirring for 45 min. After completion, solid NaHCO.sub.3 was added to neutralize the reaction, then water was added and the aqueous layer was extracted with DCM three times. The organic layer was washed with brine, dried over Na.sub.2SO.sub.4 and concentrated. The residue was purified using silica gel column chromatography (eluent: 20% −60% EtOAc/hexanes) to give 2,3-di-O-acetyl-5-deoxy-5-phthalimido-α/β-D-ribofuranose as a mixture of anomers α:β=1:3 (200 mg, 41%) that was used directly in the next step. 2,3-Di-O-acetyl-5-deoxy-5-phthalimido-α/β-D-ribofuranose (190 mg, 0.53 mmol) and trichloroacetonitrile (2 mL) were dissolved in dry DCM (2 mL) and ice-cooled before addition of DBU (2 drops). The reaction mixture was stirred at rt for 5 min and concentrated. The crude product was passed through a silica gel column, basified with 0.5% triethylamine/hexanes, eluting with 0.5% triethylamine in EtOAc/hexanes to give compound J (270 mg, quant) which was used in the next step without further purification.

(67) 5-O-β-(2′″, 3′″-Di-O-acetyl-5′″-deoxy-5′″-phthalimido-D-ribofuranosyl)-6,2″,3″,6″-tetra-O-acetyl-1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin (K). Donor I (190 mg, 0.52 mmol), acceptor A (701 mg, 0.84 mmol) and activated 4 Å MS were stirred in dry DCM (3 mL) at rt for 1 h before cooling to 0° C. BF.sub.3.OEt.sub.2 (400 μL, 1.08 mmol) was added and reaction mixture was stirred for 2 h at 0° C. The reaction was quenched with triethylamine (0.5 mL) and filtered through Celite® before it was diluted with EtOAc and washed with aqueous NaHCO.sub.3 and brine. The organic layer was dried over Na.sub.2SO.sub.4and concentrated. The crude product was purified using silica gel column chromatography (eluent: 0.6%-1.5% methanol/DCM) to give the glycoside K (470 mg, 76%) as the β anomer in the form of a white solid; [α].sub.D.sup.25=+131.96 (c 5.3, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.95-7.88 (m, 2H, ArH), 7.77-7.70 (m, 2H, ArH), 5.39 (t, J=9.9 Hz, 1H, H-3″), 5.34 (d, J=3.8 Hz, 2H, H-1′, H-1″), 5.30 (s, 1H, H-1′″), 5.12 (d, J=4.9 Hz, 1H, H-2′″), 5.06 (dd, J=7.2, 4.8 Hz, 1H, H-3″), 4.95-4.88 (m, 2H, H-8′, H-2″), 4.83 (dd, J=8.2, 2.9 Hz, 1H, H-6′), 4.66 (dd, J=10.5, 2.9 Hz, 1H, H-5′), 4.46 (t, J=9.9 Hz, 1H, H-6), 4.42-4.29 (m, 2H, H-6″, H-4′″), 4.22 (dd, J=12.2, 5.2 Hz, 1H, H-6″), 3.96 (d, J=5.0 Hz, 2H, H-5′″), 3.84-3.68 (m, 3H, H-4′, H-6′, H-5″), 3.65-3.53 (m, 3H, H-3, H-4, H-4″), 3.46-3.28 (m, 3H, H-1, H-5, H-2′), 2.94 (s, 3H, NCH.sub.3), 2.41 (dt, J=12.6, 4.3 Hz, 1H, H-2), 2.23 (s, 4H, H-3′, COCH.sub.3), 2.13-1.98 (m, 15H, 5*COCH.sub.3), 1.78 (q, J=11.7 Hz, 1H, H-3′), 1.43 (q, J=12.6 Hz, 1H, H-2);.sup.13C NMR (101 MHz, CDCl.sub.3): δ 170.3 (C═O), 170.2 (C═O), 169.9 (C═O), 169.8 (C═O), 169.5 (C═O), 168.2 (C═O), 157.2 (C═O), 134.1 (ArC), 132.0 (ArC), 123.7 (ArC), 106.9 (C-1′″), 97.0 (C-1′), 94.8 (C-8′), 93.8 (C-1″), 79.8 (C-5), 79.1 (C-4′″), 78.9 (C-4), 74.0 (2′″), 73.4 (C-6), 72.6 (C-3′″), 70.7 (C-6′), 70.3 (C-3″), 69.9 (C-2″), 68.9 (C-5″), 65.4 (C-5′), 65.3 (C-4′), 62.9 (C-6″), 60.21 (C-7′), 60.16 (C-4″), 58.4 (C-3), 58.2 (C-1), 57.7 (C-2), 39.5 (C-5′″), 31.4 (C-2), 31.3 (C-3′), 29.9 (NCH.sub.3), 20.9 (COCH.sub.3), 20.8 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3), 20.6 (COCH.sub.3), 20.4 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.47H.sub.54N.sub.14NaO.sub.23 [M+Na].sup.+ 1205.3384; found, 1205.3359.

(68) 5-O-β-(5′″-Formamido-5′″-deoxy-D-ribefuranosyl) apramycin pentaacetate salt (DCWSU177). To a stirred solution of compound K (50 mg, 0.04 mmol) in an IPA:water mixture (7:3, 1.5 mL), NaBH.sub.4 (90 mg, 2.4 mmol) was added followed by stirring for 2 h. The reaction mixture was diluted with methanol and glacial acetic acid was added dropwise until effervescence stopped. The reaction mixture was concentrated in vacuo followed by the addition of 3 N NaOH (0.5 mL) and water (0.5 mL). The reaction mixture was heated at 100° C. for 1 h before it was cooled, neutralized with glacial acetic acid and concentrated. The crude mixture was desalted using a Sephadex column and the product-containing fractions were concentrated. A part of the solid residue (8.2 mg, 0.009 mmol) was dissolved in water (0.2 mL) and treated with N-(diethylcarbamoyl)-N-methoxyformamide (2.4 μL, 0.014 mmol) and triethylamine (1 μL). The reaction mixture was stirred for 2 h and quenched with ammonium hydroxide (0.25 mL) followed by addition of 1M P(CH.sub.3).sub.3 in THF (0.3 mL) and stirring at 60° C. for 3 h. The reaction mixture was then concentrated to dryness and dissolved in aqueous acetic acid solution (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with acetic acid and lyophilized to afford DCWSU177 in (4.5 mg, 42%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+82.2 (c 0.2, H.sub.2O);.sup.1H NMR (600 MHz, D.sub.2O): δ 7.98 (s, 1H, CHO), 5.67 (d, J=3.9 Hz, 1H, H-1′), 5.34 (d, J=3.9 Hz, 1H, H-1″), 5.14 (d, J=2.9 Hz, 1H, H-1′“), 5.06 (d, J=8.5 Hz, 1H, H-8′), 4.46-4.39 (m, 1H, H-6′), 4.02 (dd, J=4.4, 3.2 Hz, 1 H, H-2”), 3.94 (t, J=5.3 Hz, 1H, H-3′″), 3.90 (q, J=5.7 Hz, 1H, H-3′″), 3.85-3.67 (m, 6H, H-4, H-5, H-4′, H-3″, H-5″, H-6), 3.63 (dd, J=12.5, 4.6 Hz, 1H, H-6″), 3.56 (dd, J=9.8, 3.8 Hz, 1H, H-2″), 3.54-3.50 (m, 3H, H-6, H-2′, H-5′), 3.42 (dd, J=14.6, 4.2 Hz, 1H, H-5″′), 3.32 (dd, J=14.6, 6.2 Hz, 1H, H-5′″), 3.29-3.23 (m, 1H, H-3), 3.22 (dd, J=8.5, 2.7 Hz, 1H, H-7′), 3.16 (td, J=11.6, 10.9, 4.3 Hz, 1H, H-1), 3.10 (t, J=10.3 Hz, 1H, H-4″), 2.63 (s, 3H, NCH.sub.3), 2.30-2.16 (m, 2H, H-2, H-3′), 1.94-1.83 (m, 1H, H-3′), 1.68-1.55 (m, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 164.7(CHO), 110.0 (C-1′″), 94.4 (C-1″), 94.0 (C-1′), 92.9 (C-8′), 85.1 (C-5), 80.9 (C-4′″), 76.4 (C-4), 74.7 (C-2′″), 72.5 (C-6), 70.8 (C-3′″), 70.2 (C-2″), 69.7 (C-5″), 69.7 (C-4′), 68.6 (C-3″), 65.9 (C-5′), 62.7 (C-6′), 60.3 (C-6″), 59.4 (C-7′), 52.0 (C-4″), 49.8 (C-3), 48.5 (C-1), 47.7 (C-2′), 40.0 (C-5′″), 30.0 (NCH.sub.3), 28.9 (C-2), 26.8 (C-3′); ESI-HRMS: m/z calcd. for C.sub.27H.sub.51N.sub.6O.sub.15 [M+H].sup.+ 699.3412; found, 699.3410.

Example 10

DCWSU 178

(69) See the synthetic scheme of FIG. 6.

(70) 5-O-Benzyl-3-O-(2-benzyloxyethyl)-1,2-O-isopropylidene-α-D-ribofuranose (g). 5-O-benzyl-1,2-O-isopropylidene-α-D-ribofuranose f (1.00 g, 3.57 mmol) was dissolved in dry THF (20 mL) and NaH (185 mg, 4.64 mmol) was added under argon. After stirring for 15 min, 2-benzyloxyethyl tosylate (1.31 g, 4.29 mmol) was added and stirring continued for 12 h. More NaH (185 mg, 4.64 mmol) and 2-benzyloxyethyl tosylate (1.31 g, 4.29 mmol) were added and the mixture stirred for 24 h. After completion, the reaction was quenched with methanol, diluted with EtOAc and washed with aqueous NaHCO.sub.3 and brine. The organic layer was dried over Na.sub.2SO.sub.4 and concentrated. The crude product was purified using silica gel column chromatography (eluent: 5% to 12% EtOAc/hexanes) to give g (1.24 g, 83%) in the form of a colorless oil; [α].sub.D.sup.25=+42.22 (c 2.2, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.39-7.26 (m, 10H, ArH), 5.77 (d, J=3.7 Hz, 1H, H-1), 4.63 (d, J=4.1 Hz, 1H, H-2), 4.61 (d, J=4.1 Hz, 1H, CH.sub.2Ph), 4.58-4.52 (m, 3H, CH.sub.2Ph), 4.14 (ddd, J=9.1, 4.1, 2.0 Hz, 1H, H-4), 3.92-3.76 (m, 3H, H-3, H-5, CH.sub.2CH.sub.2), 3.76-3.56 (m, 4H, H-5, 3H—CH.sub.2CH.sub.2), 1.57 (s, 3H, CH.sub.3), 1.35 (s, 3H, CH.sub.3); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 138.2 (ArC), 138.1 (ArC), 128.4 (ArC), 128.3 (ArC), 127.73 (ArC), 127.69 (ArC), 127.67 (ArC), 127.63 (ArC), 127.59 (ArC), 112.8(C(CH.sub.3).sub.2), 104.0 (C-1), 79.0 (C-3), 77.9 (C-4), 77.5 (C-2), 73.5 (CH.sub.2Ph), 73.2 (CH.sub.2Ph), 70.7 (CH.sub.2CH.sub.2), 70.1 (CH.sub.2CH.sub.2), 68.2 (C-5), 26.8 (CH.sub.3), 26.5 (CH.sub.3); ESI-HRMS: m/z calcd. for C.sub.24H.sub.30NaO.sub.6 [M+Na].sup.+ 437.1940; found, 437.1939.

(71) 5-O-Benzyl-3-O-(2-benzyloxyethyl)-1,2-di-O-(4-nitrobenzoyl)-α-D-ribofuranose (hα) and 5-O-Benzyl-3-O-(2-benzyloxyethyl)-1,2-di-O-(4-nitrobenzoyl)-β-D-ribofuranose (hβ). To a stirred solution of compound g (600 mg, 1.45 mmol) in dioxane (10 mL), 1 N HCl (5 mL) was added and the reaction mixture was heated at 80° C. for 45 min. The reaction mixture was cooled, neutralized with solid NaHCO.sub.3 then the solvent was evaporated. The residue was dissolved in EtOAc and washed with water and brine. The organic layer was dried over Na.sub.2SO.sub.4 and concentrated. To a solution of the residue in dry pyridine (10 mL), p-nitrobenzoyl chloride (672 mg, 3.6 mmol) and a catalytic amount of DMAP were added followed by stirring overnight. The reaction mixture was concentrated then diluted with EtOAc and washed with aqueous NaHCO.sub.3, brine, dried with Na.sub.2SO.sub.4 and concentrated. The crude product was purified using silica gel column chromatography (eluent: 5%-25% EtOAc/hexanes) to give h α:β=1:1.5 (820 g, 84%, yellow oil). Further purification was done to separate analytical sample of anomers: hα (86 mg, 9%, yellow oil), hβ (63 mg, 6%, yellow oil); α anomer: [α].sub.D.sup.25=+74.69 (c 5.7, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 8.26-8.21 (m, 2H, ArH), 8.19-8.14 (m, 2H, ArH), 8.11-8.07 (m, 4H, ArH), 7.42-7.27 (m, 5H, ArH), 7.27-7.22 (m, 3H, ArH), 7.20-7.06 (m, 2H, ArH), 6.81 (d, J=4.4 Hz, 1H, H-1), 5.47 (dd, J=6.3, 4.4 Hz, 1H, H-2), 4.66-4.53 (m, 3H, H-4, CH.sub.2Ph), 4.49-4.41 (m, 2H, CH.sub.2Ph), 4.38 (dd, J=6.3, 2.8 Hz, 1H, H-3), 3.81-3.73 (m, 2H, CH.sub.2CH.sub.2), 3.71-3.65 (m, 2H, H-5), 3.66-3.56 (m, 2H, CH.sub.2CH.sub.2); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 163.7 (C═O), 163.6 (C═O), 150.7 (ArC), 150.7 (ArC), 137.8 (ArC), 137.6 (ArC), 135.1 (ArC), 134.5 (ArC), 131.0 (ArC), 130.7 (ArC), 128.5 (ArC), 128.4 (ArC), 127.9 (ArC), 127.7 (ArC), 127.3 (ArC), 123.6 (ArC), 96.0 (C-1), 85.0 (C-4), 76.9 (C-3), 73.7 (CH.sub.2Ph), 73.4 (CH.sub.2Ph), 73.2 (C-2), 71.2 (CH.sub.2CH.sub.2), 69.9 (CH.sub.2CH.sub.2), 69.5 (C-5); ESI-HRMS: m/z calcd. for C.sub.35H.sub.32N.sub.2NaO.sub.12 [M+Na].sup.+ 695.1853; found, 695.1859; β anomer: [α].sub.D.sup.25=−11.33 (c 0.042, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 8.22 (m, 4H, ArH), 8.12-8.05 (m, 2H, ArH), 8.05-7.99 (m, 2H, ArH), 7.29-7.16 (m, 10H, ArH), 6.55 (s, 1H, H-1), 5.74 (d, J=4.4 Hz, 1H, H-2), 4.66 (dd, J=7.7, 4.4 Hz, 1H, H-3), 4.51 (s, 2H, CH.sub.2Ph), 4.46-4.39 (m, 3H, H-4, CH.sub.2Ph), 3.85 (dd, J=11.0, 2.7 Hz, 1H, H-5), 3.83-3.75 (m, 2H, CH.sub.2CH.sub.2), 3.72 (dd, J=11.1, 3.5 Hz, 1H, H-5), 3.64-3.53 (m, 2H, CH.sub.2CH.sub.2); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 163.6 (C═O), 163.0 (C═O), 150.7 (ArC), 150.6 (ArC), 137.9 (ArC), 137.8 (ArC), 134.6 (ArC), 131.0 (ArC), 130.9 (ArC), 128.4 (ArC), 128.3 (ArC), 127.7 (ArC), 127.6 (ArC), 127.5 (ArC), 123.6 (ArC), 123.5 (ArC), 99.5 (C-1), 82.2 (C-4), 77.3 (C-3), 75.2 (C-2), 73.5 (CH.sub.2Ph), 73.2 (CH.sub.2Ph), 71.1 (CH.sub.2CH.sub.2), 69.7 (CH.sub.2CH.sub.2), 68.8 (C-5); ESI-HRMS: m/z calcd. for C.sub.35H.sub.32N.sub.2NaO.sub.12 [M+Na].sup.+ 695.1853; found, 695.1846.

(72) 5-O-β-[5′″-O-Benzyl-3′″-O-(2-benzyloxyethyl)-1′″,2′″-di-O-(4-nitrobenzoyl)-D-ribefuranosyl]-6,2″,3″,6″-tetra-O-acetyl-1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin (i). Donor h (161 mg, 0.24 mmol), acceptor A (67 mg, 0.08 mmol) and activated 4 Å MS were stirred in dry DCM at rt for 1 h before cooling to 0° C. BF.sub.3.OEt.sub.2(100 μL, 0.27 mmol) was added and reaction mixture was stirred for 48 h at 0° C. The reaction was quenched with triethylamine (0.5 mL) and filtered through Celite® before dilution with EtOAc and washing with aqueous NaHCO.sub.3 and brine and concentration. The crude product was purified using silica gel column chromatography (eluent: 0.6%-1.5% methanol/DCM) to give the β anomer i (14 mg, 13%) as a white solid. An approximately equal amount of the α-anomer was also obtained but not charwcterized. [α].sub.D.sup.25=+56.85 (c 0.7, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 8.20-8.11 (m, 4H, ArH), 7.40-7.30 (m, 5H, ArH), 7.24-7.10 (m, 5H, ArH), 5.80 (d, J=3.6 Hz, 1H, H-1′), 5.43 (t, J=10.0 Hz, 1H, H-3″), 5.39-5.34 (m, 2H, H-1″, H-1′″), 5.26 (d, J=4.3 Hz, 1H, H-2′″), 4.91 (t, J=9.7 Hz, 1H, H-6), 4.87 (dd, J=10.3, 3.9 Hz, 1H, H-2”), 4.81 (d, J=4.5 Hz, 1H, H-8′), 4.76 (dd, J=7.4, 3.3 Hz, 1H, H-6′), 4.57 (d, J=12.0 Hz, 1H, CH.sub.2Ph), 4.51 (d, J=12.0 Hz, 1H, CH.sub.2Ph), 4.39 (dd, J=10.3, 3.4 Hz, 1H, H-5′), 4.37-4.31 (m, 3H, CH.sub.2Ph, H-6″), 4.27-4.19 (m, 2H, H-6″, H-4′″), 4.14 (dd, J=7.5, 4.4 Hz, 1H, H-3′″), 3.87-3.71 (m, 4H, H-5, H-7′, H-5″, H-5′″), 3.71-3.63 (m, 3H, H-4, CH.sub.2CH.sub.2), 3.63-3.52 (m, 4H, H-3, H-5″ H-4′, H-4″), 3.51-3.37 (m, 3H, H-1, CH.sub.2CH.sub.2), 3.08 (dt, J=12.9, 4.2 Hz, 1H, H-2′), 2.95 (s, 3H, NHCH.sub.3), 2.41 (dt, J=13.1, 4.5 Hz, 1H, H-2), 2.23-1.97 (m, 13H, 4COCH.sub.3, H-3′), 1.87 (q, J=11.7 Hz, 1H, H-3′), 1.57 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.3 (C═O), 170.1 (C═O), 169.8 (C═O), 169.7 (C═O), 163.8 (C═O), 157.1 (ArC), 150.7 (ArC), 137.9 (ArC), 137.9 (ArC), 134.7 (ArC), 130.8 (ArC), 128.5 (ArC), 128.2 (ArC), 127.7 (ArC), 127.6 (ArC), 127.5 (ArC), 127.4 (ArC), 123.6 (ArC), 107.2 (C-1′″), 97.3 (C-8′), 96.4 (C-1′), 94.2 (C-1″), 82.0 (C-5), 80.7 (C-4′″), 77.8 (C-4), 77.7 (C-3′″), 75.7 (C-2″), 75.0 (C-6), 73.4 (CH.sub.2Ph), 73.0 (CH.sub.2Ph), 71.0 (C-6′), 70.8 (C-3″), 70.4 (CH.sub.2CH.sub.2), 70.3 (C-5′″), 69.9 (C-2″), 69.2 (C-5″), 69.1 (CH.sub.2CH.sub.2), 65.9 (C-5′), 65.7 (C-4′), 62.9 (C-6″), 60.20 (C-4″), 60.17 (C-7′), 59.1 (C-3), 58.1 (C-1), 56.5 (C-2′), 31.3 (C-2), 30.1 (C-3′), 29.7 (NCH.sub.3), 20.9 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.58H.sub.66N.sub.14NaO.sub.24 [M+Na].sup.+ 1365.4272; found, 1365.4260.

(73) 5-O-β-[3′″-O-(2-Hydroxyethyl)-D-ribofuranosyl] apramycin pentaacetate salt (DCWSU178). A stirred solution of compound i (10 mg, 0.01 mmol) in dioxane (0.5 mL) was treated with 3N NaOH (0.25 mL) and heated at 100° C. for 3 h. The reaction mixture was cooled to rt and neutralized with Amberlyst® before concentration in vacuo. The crude product was dissolved in dioxane:water:glacial acetic acid=1:2:0.2 (0.3 mL) and Pd(OH).sub.2/C (0.5 equiv) was added. The reaction mixture was stirred at room temperature under 50 psi of hydrogen for 12 h. After completion, the reaction mixture was filtered through Celite® and concentrated to dryness. The residue was then dissolved in aqueous acetic acid solution (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted with 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with glacial acetic acid and lyophilized to afford DCWSU178 (3.5 mg, 48%) as the peracetate salt in the form of a white solid; [α].sub.D.sup.25=+72.0 (c 0.1, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.72 (d, J=3.6 Hz, 1H, H-1′), 5.34 (d, J=3.8 Hz, 1H, H-1″), 5.20 (s, 1H, H-1′″), 5.06 (d, J=8.5 Hz, 1H, H-8′), 4.43 (s, 1H, H-6′), 4.21 (d, J=4.3 Hz, 1H, H-2′″), 3.97-3.92 (m, 1H, H-4′″), 3.91-3.86 (m, 1H, H-4), 3.86-3.79 (m, 2H, H-5″, H-3′″), 3.78-3.66 (m, 7H, H-5, H-4′, H-5′″, H-6″, H-3″, CH.sub.2CH.sub.2), 3.63 (dd, J=12.4, 4.6 Hz, 1H, H-6″), 3.60-3.55 (m, 3H, H-2″,CH.sub.2CH.sub.2), 3.55-3.45 (m, 4H, H-6, H-2′, H-6′, H-5′″), 3.42-3.33 (m, 1H, H-3), 3.24 (d, J=8.9 Hz, 1H, H-7′), 3.21-3.09 (m, 2H, H—, H-1, H-4″), 2.63 (s, 3H, NCH.sub.3), 2.32 (dt, J=12.3, 3.8 Hz, 1H, H-2), 2.23-2.15 (m, 1H, H-3′), 1.94-1.90 (m, 1H, H-3′), 1.70 (q, J=12.8 Hz, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): δ 110.4 (C-1′″), 94.6 (C-1′), 94.4 (C-1″), 92.8 (C-8′), 84.8 (C-5), 81.1 (C-4′″), 77.0 (C-3′″), 75.2 (C-4), 73.4 (C-2″), 72.4 (C-6), 71.4 (CH.sub.2CH.sub.2), 70.2 (C-5″), 69.7 (C-2″), 69.3 (C-3″), 68.2 (C-4′), 66.0 (C-5′), 62.6 (C-6′), 60.9 (C-5′″), 60.5 (CH.sub.2CH.sub.2), 60.3 (C-6″), 59.3 (C-7′), 52.0 (C-4″), 49.7 (C-3), 48.3 (C-1), 47.8 (C-2′), 30.0 (NCH.sub.3), 28.0 (C-2), 26.6 (C-3′); ESI-HRMS: m/z calcd. for C.sub.28H.sub.54N.sub.5O.sub.16 [M+H].sup.+ 716.3566; found, 716.3541.

Example 11

DCWSU 185 and 186

(74) See the synthetic scheme of FIG. 7.

(75) 5-Azido-3-O-(2-benzyloxyethyl)-5-deoxy-1,2-O-isopropylidene-α-D-ribofuranose (M). 5-Azido-5-deoxy-1,2-O-isopropylidene-α-D-ribofuranose L (4.0 g, 18.6 mmol) was dissolved in dry THF (100 mL) and NaH (100 mg, 24.5 mmol) was added. After stirring for 15 min, 2-benzyloxyethyl tosylate (6.83 g, 22.3 mmol) was added and stirring continued for 36 h. After completion, the reaction was quenched with methanol, diluted with EtOAc and washed with aqueous NaHCO.sub.3 and brine then concentrated. The crude product was purified using silica gel column chromatography (eluent: 10% to 20% EtOAc/hexanes) to give M (3.08 g, 47%) in the form of a colorless oil; [α].sub.D.sup.25=+119.83 (c 1.2, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.45-7.21 (m, 5H, ArH), 5.76 (d, J=3.5 Hz, 1H, H-1), 4.64 (t, J=3.9 Hz, 1H, H-2), 4.56 (s, 2H, CH.sub.2Ph), 4.14 (dt, J=8.5, 3.2 Hz, 1H, H-4), 3.91-3.71 (m, 2H, H-3, CH.sub.2CH.sub.2), 3.76-3.64 (m, 4H, H—, CH.sub.2CH.sub.2, CH.sub.2CH.sub.2, H-5), 3.32 (dd, J=13.5, 4.0 Hz, 1H, H-5), 1.57 (s, 3H, CH.sub.3), 1.35 (s, 3H, CH.sub.3); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 138.0 (ArC), 128.4 (ArC), 127.7 (ArC), 113.2(C(CH.sub.3).sub.2), 103.9 (C-1), 79.5 (C-3), 77.4 (C-4), 77.3 (C-2), 73.3 (CH.sub.2Ph), 70.1 (CH.sub.2CH.sub.2), 69.7 (CH.sub.2CH.sub.2), 50.6 (C-5), 26.8(CH.sub.3), 26.5(CH.sub.3). ; ESI-HRMS: m/z calcd. for C.sub.17H.sub.23N.sub.3NaO.sub.5 [M+Na].sup.+ 372.1535; found, 372.1538.

(76) 5-Benzyloxycarbonylamino-5-deoxy-3-O-(2-hydroxyethyl)-1,2-O-isopropylidene-α-D-ribofuranose (N). To a solution of compound (M) (3.0 g, 8.6 mmol) in dioxane:water=5:1 (30 mL), 20% Pd(OH).sub.2/C (3.0 g, 0.5 equiv) was added and the reaction mixture stirred at room temperature under 50 psi of hydrogen for 18 h. After completion, the reaction mixture was filtered over Celite®, concentrated to dryness and dissolved in dioxane:water=3:1 (50 mL). K.sub.2CO.sub.3 (6.0 g, 43.5 mmol) and benzyloxy chloroformate (2.5 mL, 17.2 mmol) were added and the reaction mixture was stirred for 4 h. After completion, the reaction mixture was concentrated and purified using silica gel column chromatography (eluent: 0.8% to 1% methanol/DCM) to give N (1.67 g, 53%) as a colorless oil; [α].sub.D.sup.25=+35.47 (c 1.5, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.41-7.28 (m, 5H, ArI-1), 5.73 (d, J=3.8 Hz, 1H, H-1), 5.10 (d, J=1.4 Hz, 2H (CH.sub.2Ph)), 4.60 (t, J=4.1 Hz, 1H, H-2), 4.03 (dt, J=9.0, 3.6 Hz, 1H, H-4), 3.77-3.61 (m, 5H, CH.sub.2CH.sub.2, CH.sub.2CH.sub.2, H-5), 3.55 (dd, J=9.0, 4.4 Hz, 1H, H-3), 3.45 (dt, J=14.6, 4.2 Hz, 1H, H-5), 3.04 (t, J=5.8 Hz, 1H, OH), 1.56 (s, 3H, CH.sub.3), 1.35 (s, 3H, CH.sub.3);.sup.13C NMR (101 MHz, CDCl.sub.3): δ 156.9 (C═O), 136.3 (ArC), 128.5 (ArC), 128.2 (ArC), 113.1(C(CH.sub.3).sub.2), 104.1 (C-1), 79.3 (C-3), 77.1 (C-2), 77.0 (C-4), 72.0 (CH.sub.2CH.sub.2), 67.0 (CH.sub.2Ph), 61.6 (CH.sub.2CH.sub.2), 40.6 (C-5), 26.6 (CH.sub.3), 26.5 (CH.sub.3); ESI-HRMS: m/z calcd. for C.sub.18H.sub.25NNaO.sub.7 [M+Na].sup.+ 390.1529; found, 390.1537.

(77) 3-O-(2-Azidoethyl)-5-benzyloxycarbonylamino-5-deoxy-1,2-O-isopropylidene-α-D-ribofuranose (O). To a stirred solution of the alcohol N (1.0 g, 2.7 mmol) in dry THF (5 mL), triethylamine (2.8 mL, 20.4 mmol). The reaction mixture was ice-cooled before addition of p-tolylsulfonyl chloride (975 mg, 5.13 mmol) in dry THF (5 mL). The reaction mixture was stirred at 30° C. for 48 h before it was concentrated in vacuo. The crude product was dissolved in EtOAc and washed with aqueous NaHCO.sub.3 and brine, dried over Na.sub.2SO.sub.4, and concentrated. The resulted solid was dissolved in dry DMF (10 mL) and treated with NaN.sub.3 (1.05 g, 16.3 mmol) and stirred at 40° C. for 48 h. After completion, the reaction mixture was diluted with acetone and excess NaN.sub.3 was filtered off. The solvent was partially removed under vacuum and the residue was diluted with EtOAc, washed with brine, dried over Na.sub.2SO.sub.4, and filtered. The solvent was removed under vacuum and the resulting product was purified using silica gel column chromatography (eluent: 10% to 25% EtOAc/hexanes) to give 0 (900 mg, 84% over two steps) as a viscous oil; [α].sub.D.sup.25=+35.38 (c 1.9, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 739-7.27 (m, 5H, ArI-1), 5.73 (d, J=3.7 Hz, 1H, H-1), 5.10 (s, 2H, CH.sub.2Ph), 4.60 (t, J=4.1 Hz, 1H, H-2), 4.05 (dt, J=8.6, 4.1 Hz, 1H, H-4), 3.82 (ddd, J=10.1, 6.0, 3.8 Hz, 1H, CH.sub.2O), 3.67 (ddd, J=10.3, 6.5, 3.9 Hz, 1H, CH.sub.2O), 3.63-3.47 (m, 3H, H-3, H-5), 3.47-3.32 (m, 2H, CH.sub.2N.sub.3), 1.56 (s, 3H, CH.sub.3), 1.34 (s, 3H, CH.sub.3);.sup.13C NMR (101 MHz, CDCl.sub.3): δ 156.5 (C═O), 136.4 (ArC), 128.5 (ArC), 128.1 (ArC), 113.3(C(CH.sub.3).sub.2), 104.1 (C-1), 80.0 (C-3), 77.1 (C-2), 77.0 (C-4), 69.4 (CH.sub.2O), 66.9 (CH.sub.2Ph), 50.7 (CH.sub.2N.sub.3), 41.1 (C-5), 26.7 (CH.sub.3), 26.6 (CH.sub.3); ESI-HRMS: m/z calcd. for C.sub.18H.sub.24N.sub.4NaO.sub.6 [M+Na].sup.+415.1594; found, 415.1589.

3-O-(2-Azidoethyl)-5-di(benzyloxycarbonyl)amino-5-deoxy-1,2-O-isopropylidene-α-D-ribofuranose (P)

(78) A stirred solution of the compound O (200 mg, 0.51 mmol) in dry THF (8 mL) and HMPA (2 mL), was cooled to -78° C. under argon before KHMDS (0.5 M in toluene, 1.5 mL, 0.66 mmol) and benzyloxychloroformate (0.3 mL, 2.1 mmol) were added. The reaction mixture was stirred at −78° C. for 2 h before additional KHMDS (0.5 M in toluene, 3 mL, 1.5 mmol) was added. The reaction was stirred for 30 min and quenched with NH.sub.4Cl, diluted with EtOAc, and washed with aqueous NaHCO.sub.3 and brine. The organic layer was dried over Na.sub.2SO.sub.4 and concentrated. The crude product was purified using silica gel column chromatography (eluent: 10% to 25% EtOAc/hexanes) to give P (272 mg, quant) [α].sub.D.sup.25=+14.73 (c 1.5, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.48-7.28 (m, 10H, ArH), 5.70 (d, J=3.8 Hz, 1H, H-1), 5.42-5.12 (m, 4H, CH.sub.2Ph), 4.56 (t, J=4.1 Hz, 1H, H-2), 4.20 (dt, J=8.9, 5.4 Hz, 1H, H-4), 4.07 (dd, J=5.4, 1.2 Hz, 2H, H-5), 3.72 (ddd, J=9.9, 6.0, 4.0 Hz, 1H, CH.sub.2O), 3.57 (dd, J=8.8, 4.4 Hz, 1H, H-3), 3.45 (ddd, J=10.1, 6.3, 4.2 Hz, 1H, CH.sub.2O), 3.34-3.16 (m, 2H, CH.sub.2N.sub.3), 1.51 (s, 3H, CH.sub.3), 1.33 (s, 3H, CH.sub.3);.sup.13C NMR (101 MHz, CDCl.sub.3): δ 153.6 (C═O), 135.2 (ArC), 128.5 (ArC), 128.3 (ArC), 128.2 (ArC), 128.1 (ArC), 113.1(C(CH.sub.3).sub.2), 104.2 (C-1), 81.3 (C-3), 77.4 (C-2), 77.1 (C-4), 68.9 (CH.sub.2O), 68.8 (CH.sub.2Ph), 66.9 (CH.sub.2Ph), 50.5 (CH.sub.2N.sub.3), 47.1 (C-5), 26.7 (201-1.sub.3); ESI-HRMS: m/z calcd. for C.sub.26H.sub.30N.sub.4NaO.sub.8 [M+Na].sup.+ 549.1961; found, 549.1962.

(79) 3-O-(2-Azidoethyl)-5-di(benzyloxycarbonyl)amino-5-deoxy-1,2-di-O-(p-nitrobenzoyl)-α/β-D-ribofuranose (Q). To a stirred solution of compound P (268 mg, 0.51 mmol) in dioxane (10 mL), 1 N HCl (4 mL) was added and the reaction mixture was heated at 80° C. for 2 h. The reaction mixture was cooled, neutralized with solid NaHCO.sub.3 and the solvent was evaporated. The residue was dissolved in EtOAc and washed with water and brine, dried with Na.sub.2SO.sub.4 and evaporated. To a solution of the crude mixture in dry pyridine (10 mL), p-nitrobenzoyl chloride (672 mg, 3.6 mmol) and a catalytic amount of DMAP were added followed by stirring overnight. The reaction mixture was diluted with EtOAc and washed with NaHCO.sub.3, brine, dried with Na.sub.2SO.sub.4 then concentrated. The crude product was purified using silica gel column chromatography (eluent: 15%-40% EtOAc/hexanes) to give the oc isomer (235 mg, 59%) as a white solid and the β isomer (165 mg, 41%) as a white solid; a isomer: [α].sub.D.sup.25=+13.85 (c 0.4, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 8.31-8.17 (m, 6H, ArH), 8.12 (d, J=8.8 Hz, 2H, ArH), 7.48-7.17 (m, 10H, ArH), 6.64 (d, J=4.4 Hz, 1H, H-1), 5.36 (dd, J=6.6, 4.4 Hz, 1H, H-2), 5.34-5.21 (m, 4H, 2*CH.sub.2Ph), 4.61 (td, J=6.2, 3.8 Hz, 1H, H-4), 4.18 (dd, J=6.6, 3.8 Hz, 1H, H-3), 4.15-3.99 (m, 2H, H-5), 3.47 (t, J=4.8 Hz, 2H, CH.sub.2CH.sub.2O), 3.20-3.12 (m, 2H, CH.sub.2N.sub.3)..sup.13C NMR (101 MHz, CDCl.sub.3): δ 163.6 (C═O), 163.3 (C═O), 153.5 (C═O), 150.9 (ArC), 150.8 (ArC), 148.4 (ArC), 137.3 (ArC), 134.9 (ArC), 134.8 (ArC), 134.1 (ArC), 131.0 (ArC), 130.9 (ArC), 130.8 (ArC), 128.6 (ArC), 128.4 (ArC), 123.7 (ArC), 123.4 (ArC), 95.4 (C-1), 82.6 (C-4), 77.3 (C-3), 72.4 (C-2), 70.1 (CH.sub.2CH.sub.2O), 69.3 (CH.sub.2Ph), 50.9 (CH.sub.2N.sub.3), 47.7 (C-5); ESI-HRMS: m/z calcd. for C.sub.37H.sub.32N.sub.6NaO.sub.14 [M+Na].sup.+ 807.1874; found, 807.1852; β isomer: [α].sub.D.sup.25=−32.63 (c 0.5, DCM); .sup.1H NMR (400 MHz, CDCl.sub.3): δ 8.53-7.91 (m, 8H, ArH), 7.29 (s, 10H, ArH), 6.52 (s, 1H, H-1), 5.71 (d, J=4.1 Hz, 1H, H-2), 5.19 (q, J=12.3 Hz, 4H, 2*CH.sub.2Ph), 4.46 (dt, J=8.1, 4.9 Hz, 1H, H-4), 4.39 (dd, J=8.0, 4.2 Hz, 1H, H-3), 4.30-4.14 (m, 2H, H-5), 3.73 (ddd, J=9.9, 6.8, 3.3 Hz, 1H, CH.sub.2CH.sub.2O), 3.57 (ddd, J=9.5, 6.0, 3.3 Hz, 1H, CH.sub.2O), 3.30-3.04 (m, 2H, CH.sub.2N.sub.3); .sup.13C NMR (101 MHz, CDCl.sub.3): δ 163.5 (C═O), 162.9 (C═O), 153.9 (C═O), 150.9 (ArC), 150.7 (ArC), 134.9 (ArC), 134.4 (ArC), 134.3 (ArC), 131.1 (ArC), 131.0 (ArC), 128.6 (ArC), 128.5 (ArC), 128.2 (ArC), 128.1 (ArC), 123.7 (ArC), 123.6 (ArC), 99.6 (C-1), 80.2 (C-4), 79.2 (C-3), 74.5 (C-2), 70.4 (CH.sub.2CH.sub.2O), 69.2 (CH.sub.2Ph), 50.6 (CH.sub.2N.sub.3), 47.2 (C-5); ESI-HRMS: m/z calcd. for C.sub.37H.sub.32N.sub.6NaO.sub.14 [M+Na].sup.+ 807.1874; found, 807.1877.

(80) 5-O-β-[3-O-(2-Azidoethyl)-5-di(benzyloxycarbonyl)amino-5-deoxy-2-O-p-nitrobenzoyl-D-ribofuranose]-6,2″,3″,6″-tetra-O-acetyl-1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin (R). Donor Q (β isomer, 165 mg, 0.21 mmol), acceptor A (440 mg, 0.52 mmol) and activated 4 A MS were stirred in dry DCM (3 mL) at rt for 1 h before cooling to 0° C. BF.sub.3.OEt.sub.2 (300 uL, 0.78 mmol) was added and reaction mixture was stirred for 48 h at 0° C. The reaction was quenched with triethylamine (0.5 mL) and filtered through Celite® before it was diluted with EtOAc. The organic layer was washed with aqueous NaHCO.sub.3 and brine then concentrated. The crude product was purified using silica gel column chromatography (eluent: 0.6%-1.5°/O Methanol/DCM) to give the glycoside R (136 mg, 45%) as the β anomer in the form of a white solid; [α].sub.D.sup.25=+46.26 (c 0.9, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 8.29-8.21 (m, 2H, ArH), 8.19-8.09 (m, 2H, ArH), 7.39-7.32 (m, 4H, ArH), 7.32-7.25 (m, 6H, ArH), 5.43-5.35 (m, 3H, H-1′, H-3″, H-1″), 5.32 (d, J=3.9 Hz, 1H, H-1′″), 5.31-5.26 (m, 4H, 2*CH.sub.2Ph), 5.25 (d, J=4.1 Hz, 1H, H-2′″), 4.89 (dd, J=10.3, 3.9 Hz, 1H, H-2”), 4.87 (d, J=3.4 Hz, 1H, H-8′), 4.84 (t, J=9.8 Hz, 1H, H-6), 4.78 (dd, J=8.2, 3.2 Hz, 1H, H-6′), 4.60 (dd, J=10.5, 3.2 Hz, 1H, H-5′), 4.31 (dd, J=12.3, 2.3 Hz, 1H, H-6″), 4.28-4.18 (m, 2H, H-6″, H-4′″), 4.18-4.10 (m, 2H, H-5′″), 4.08 (dd, J=7.8, 4.5 Hz, 1H, H-3′″), 3.79 (dd, J=8.2, 3.5 Hz, 1H, H-7′), 3.71 (ddd, J=10.7, 5.3, 2.3 Hz, 1H, H-5″), 3.66 (td, J=10.9, 4.3 Hz, 1H, H-4′), 3.63-3.52 (m, 4H, H-3, H-5, H-4″, CH.sub.2CH.sub.2O), 3.49-3.43 (m, 2H, H-4, CH.sub.2CH.sub.2O), 3.39 (ddd, J=12.5, 10.2, 4.2 Hz, 1H, H-1), 3.27 (dt, J=12.8, 4.3 Hz, 1H, H-2′), 3.12 (ddd, J=13.3, 7.3, 3.2 Hz, 1H, CH.sub.2N.sub.3), 3.02 (ddd, J=13.3, 5.7, 3.2 Hz, 1H, CH.sub.2N.sub.3), 2.92 (s, 3H, NCH.sub.3), 2.38 (dt, J=12.9, 4.5 Hz, 1H, H-2), 2.20 (s, 3H, COCH.sub.3), 2.17-2.11 (m, 1H, H-3′), 2.08 (d, J=4.4 Hz, 6H, 2*COCH.sub.3), 2.04 (s, 3H, COCH.sub.3), 1.77 (q, J=11.8 Hz, 1H, H-3′), 1.41 (q, J=12.6 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.3 (C═O), 170.0 (C═O), 169.9 (C═O), 169.4 (C═O), 163.9 (C═O), 157.0 (ArC), 153.7 (ArC), 150.8 (ArC), 135.3 (ArC), 134.4 (ArC), 130.9 (ArC), 128.5 (ArC), 128.2 (ArC), 127.9 (ArC), 123.7 (ArC), 106.7 (C-1′″), 96.8 (C-1′), 95.4 (C-8′), 94.0 (C-1″), 80.4 (C-5), 79.5 (C-3′″), 79.3 (C-4), 79.1 (C-4′″), 74.8 (C-2′”), 74.3 (C-6), 70.6 (C-3″), 70.3 (C-6′), 70.0 (CH.sub.2CH.sub.2O), 69.9 (C-2′″), 68.9 (2*CH.sub.2Ph), 65.6 (C-5′), 65.3 (C-4′), 62.9 (C-6″), 60.14 (C-7′), 60.11 (C-4″), 58.3 (C-3), 58.1 (C-1), 57.4 (C-2′), 50.6 (CH.sub.2N.sub.3), 48.2 (C-5′″), 31.3 (C-3′), 31.0 (C-2), 29.9 (NCH.sub.3), 21.0 (COCH.sub.3), 20.9 (COCH.sub.3), 20.8 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.60H.sub.66N.sub.18NaO.sub.26 [M+Na].sup.+ 1477.4293; found, 1477.4232.

(81) 5-O-β-[5-Amino-3-O-(2-aminoethyl)-5-deoxy-D-ribofuranosyl] apramycin heptaacetate salt (DCWSU185) A stirred solution of substrate R (67 mg, 0.046 mmol) in dioxane (1.5 mL) was treated with 3 N NaOH (1.5 mL) and heated at 100° C. for 18 h. The reaction mixture was cooled to 0° C. and neutralized with glacial acetic acid before it was concentrated in vacuo. The crude mixture was passed through a silica gel column (eluent: 25% methanol/DCM). The resulting solid (20 mg, 0.023 mmol) was dissolved in a water methanol:water mixture (1:1, 0.5 mL) and treated with N-(diethylcarbamoyl)-N-methoxyformamide (30 μL, 0.17 mmol) and triethylamine (2 μL). The reaction mixture was stirred for 2 h and quenched with aqueous ammonium hydroxide (0.25 mL) and concentrated. The crude product was purified using silica gel column chromatography (eluent: 5% to 15% ammonical MeOH in DCM). A part of the solid residue (12 mg, 0.014 mmol) dissolved in dioxane (3 mL) followed by the addition of 1 N NaOH (0.5 mL) and 1 M P(CH.sub.3).sub.3 in THF (0.2 mL), and stirred at 50° C. for 45 min. The reaction mixture was then concentrated to dryness and dissolved in aqueous acetic acid (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient eluted of 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the products were combined, acidified with glacial acetic acid and lyophilized to afford the peracetate salt of DCWSU185 in (14.5 mg, 56%) as a white solid; [α].sub.D.sup.25=+72.53 (c 0.7, H.sub.2O); .sup.1H NMR (600 MHz, D.sub.2O): δ 5.73 (d, J=4.0 Hz, 1H, H-1′), 5.31 (d, J=3.7 Hz, 1H, H-1″), 5.26 (s, 1H, H-1′″), 5.03 (d, J=8.6, 1H, H-8′), 4.40 (s, 1H, H-6′), 4.26 (d, J=4.4 Hz, 1H, H-2′″), 4.03 (td, J=7.5, 3.8 Hz, 1H, H-4′″), 3.93-3.86 (m, 2H, H-4, H-3′″), 3.83-3.71 (m, 4H, H-5, H-4′, H-3″, H-5″), 3.69-3.57 (m, 4H, CH.sub.2CH.sub.2O, H-6″), 3.56-3.44 (m, 4H, H-6, H-2′, H-5′, H-2″), 3.35-3.26 (m, 1H, H-3), 3.23-3.11 (m, 3H, H-1, H-7′, H-5″), 3.11-2.99 (m, 4H, H-4″, H-5, CH.sub.2CH.sub.2O), 2.59 (s, 3H, NCH.sub.3), 2.24 (dt, J=13.1, 4.4 Hz, 1H, H-2), 2.20 (dt, J=10.1, 4.7 Hz, 1H, H-3′), 1.93-1.83 (m, 1H, H-3′), 1.68-1.59 (m, 1H, H-2); .sup.13C NMR (151 MHz, D.sub.2O): 6 108.9 (C-1′“), 94.4 (C-1′), 92.7 (C-1”), 92.5 (C-8′), 83.2 (C-5), 79.2 (C-3″), 77.0 (C-4′“), 73.6 (C-4), 72.7 (C-2”), 72.0 (C-6), 70.2 (C-2″), 69.5 (C-5″, C-5′), 68.3 (C-3″), 65.9 (C-4′), 65.8 (CH.sub.2CH.sub.2O), 62.6 (C-6′), 60.2 (C-6″), 59.5 (C-7′), 52.0 (C-4″), 50.0 (C-1), 48.7 (C-3), 47.6 (C-2′), 42.1 (C-5′”), 39.2 (CH.sub.2CH.sub.2O), 30.0 (NCH.sub.3), 28.2 (C-2), 27.0 (C-3′); ESI-HRMS: m/z calcd. for C.sub.28H.sub.56N.sub.7O.sub.14 [M+H].sup.+ 714.3885; found, 714.3868.

(82) 5-β-[3-O-(2-Aminoethyl)-5-deoxy-5-formamido-D-ribofuranosyl] apramycin hexaacetate salt (DCWSU186). A stirred solution of substrate R (67 mg, 0.046 mmol) in dioxane (1.5 mL) was treated with 3 N NaOH (1.5 mL) and heated at 100° C. for 18 h. The reaction mixture was cooled to 0° C. and neutralized with glacial acetic acid before it was concentrated in vacuo. The crude mixture was passed through a silica gel column (eluent: 25% methanol/DCM). The resulting solid (20 mg, 0.023 mmol) was dissolved in a water methanol:water mixture (1:1, 0.5 mL) and treated with N-(diethylcarbamoyl)-N-methoxyformamide (30 μL, 0.17 mmol) and triethylamine (2 μL). The reaction mixture was stirred for 2 h and quenched with aqueous ammonium hydroxide (0.25 mL) and concentrated. The crude product was purified using silica gel column chromatography (eluent: 5% to 15% ammonical MeOH in DCM). A part of the solid residue (20 mg, 0.022 mmol) was dissolved in dioxane:water (1:1, 0.6 mL) followed by the addition 1 M P(CH.sub.3).sub.3 in THF (0.3 mL), and stirred at 50° C. for 45 min. The reaction mixture was then concentrated to dryness and dissolved in aqueous acetic acid solution (pH 4, 1 mL) before it was charged to a Sephadex column (CM Sephadex C-25). The column was flushed with D.I. water (20 mL), then gradient elution of 0.1%-1.0% NH.sub.4OH in D.I. water. The fractions containing the product were combined, acidified with acetic acid, and lyophilized to afford the peracetate salt of DCWSU186 in (13.9 mg, 57%) as a white solid; [α].sub.D.sup.25=+55.35 (c 0.2, H.sub.2O);.sup.1H NMR (600 MHz, D.sub.2O): δ 7.94 (s, 1H, CHO), 5.69 (d, J=3.9 Hz, 1H, H-1′), 5.30 (d, J=4.0 Hz, 1H, H-1”), 5.15 (d, J=3.0 Hz, 1H, H-1′″), 5.03 (d, J=8.6 Hz, 1H, H-8′), 4.40 (t, J=2.7 Hz, 1H, H-6′), 4.16 (dd, J=4,9,3,0 Hz, 1H, H-2′″), 3.97 (q, J=5.6 Hz, 1H, H-4′″), 3.88 (t, J=9.6 Hz, 1H, H-4), 3.83-3.68 (m, 5H, H-5, H-4′, H-3″, H-5″, H-3′″), 3.68-3.55 (m, 4H, H-6″, CH.sub.2CH.sub.2O), 3.54-3.44 (m, 4H, H-6, H-2′, H-5′, H-2″), 3.40 (dd, J=14.5, 4.6 Hz, 1H, H-5′″), 3.33 (ddd, J=14.3, 10.4, 4.3 Hz, 1H, H-3), 3.29 (dd, J=14.5, 6.1 Hz, 1H, H-5′″), 3.20 (dd, J=8.6, 2.8 Hz, 1H, H-7′), 3.18-3.12 (m, 1H, H-1), 3.10 (t, J=10.3 Hz, 1H, H-4″), 3.05-2.98 (m, 2H, CH.sub.2CH.sub.2O), 2.59 (s, 3H, NCH.sub.3), 2.28 (dt, J=12.6, 4.3 Hz, 1H, H-2), 2.18 (dt, J=11.2, 4.6 Hz, 1H, H-3′), 1.88 (d, J=11.8 Hz, 1H, H-3′), 1.72-1.63 (m, 1H, H-2);.sup.13C NMR (151 MHz, D.sub.2O): δ 164.8 (CHO), 110.3 (C-1′″), 94.4 (C-1′), 93.6 (C-1″), 92.8 (C-8′), 84.8 (C-5), 79.3 (C-4′″), 78.8 (C-3′”), 74.8 (C-4), 73.1 (C-2′″), 72.3 (C-6), 70.2 (C-2″), 69.7 (C-5″), 69.3 (C-5′), 68.2 (C-3″), 65.9 (C-4′), 65.8 (CH.sub.2CH.sub.2O), 62.6 (C-6′), 60.2 (C-6″), 59.3 (C-7′), 52.0 (C-4″), 49.6 (C-1), 48.5 (C-3), 47.6 (C-2′), 40.1 (C-5′″), 39.2 (CH.sub.2CH.sub.2O), 30.0 (NCH.sub.3), 27.9 (C-2), 26.7 (C-3′); ESI-HRMS: m/z calcd. for C.sub.29H.sub.56N.sub.7O.sub.15 [M+H].sup.+ 742.3834; found, 742.3861.

Example 12

Key Intermediate A

(83) See the synthetic scheme of FIG. 17.

(84) 6,2″,3″,6″-Tetra-O-acetyl-1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin (A). A stirred solution of 1,3,2′,4″-tetraazido-6′,7′-oxazolidino-apramycin (100 mg, 0.15 mmol) in dry pyridine (0.3 mL) was cooled to 0° C. and treated with acetic anhydride (60 μL, 0.62 mmol). The reaction mixture was allowed to warm up to rt and stirred overnight. The reaction progress was monitored by TLC and additional acetic anhydride (0.5-1 equiv) was added as needed. After completion, the reaction mixture was diluted with EtOAc and the organic layer was washed with aqueous NaHCO.sub.3 followed by brine, dried with Na.sub.2SO.sub.4, and concentrated. The crude product was purified via silica gel chromatography eluting with 0.6% to 0.8% methanol in DCM to give A (76 mg, 61%) as a white solid; [α].sub.D.sup.25=+101.6 (c 3.1, DCM); .sup.1H NMR (600 MHz, CDCl.sub.3): δ 5.35 (t, J=9.9 Hz, 1H, H-3″), 5.30 (d, J=3.7 Hz, 1H, H-1″), 5.15 (d, J=3.5 Hz, 1H, H-1′), 4.93 (d, J=2.9 Hz, 1H, H-8′), 4.93-4.87 (m, 2H, H-6, H-2″), 4.81 (dd, J=8.6, 3.2 Hz, 1H, H-6′), 4.61 (dd, J=10.5, 3.2 Hz, 1H, H-5′), 4.31 (dd, J=12.3, 2.2 Hz, 1H, H-6″), 4.20 (dd, J=12.3, 5.1 Hz, 1H, H-6″), 3.84 (dd, J=8.7, 3.0 Hz, 1H, H-7), 3.80 (dt, J=10.9, 5.5 Hz, 1H, H-4′), 3.72 (ddd, J=10.7, 5.1, 2.3 Hz, 1H, H-5″), 3.66 (ddd, J=12.3, 9.9, 4.7 Hz, 1H, H-3), 3.62-3.53 (m, 3H, H-2′, H-4″, H-5), 3.49 (ddd, J=12.5, 10.0, 4.5 Hz, 1H, H-1), 3.45 (t, J=9.5 Hz, 1H, H-4), 2.89 (s, 3H, NCH.sub.3), 2.41 (dt, J=13.3, 4.6 Hz, 1H, H-2), 2.29 (dt, J=10.9, 4.5 Hz, 1H, H-3), 2.13 (s, 3H, COCH.sub.3), 2.10 (s, 3H, COCH.sub.3), 2.10 (s, 3H, COCH.sub.3), 2.07 (s, 3H, COCH.sub.3), 1.89 (q, J=11.7 Hz, 1H, H-3), 1.60 (q, J=12.7 Hz, 1H, H-2); .sup.13C NMR (151 MHz, CDCl.sub.3): δ 170.37 (C═O), 170.34 (C═O), 169.91 (C═O), 169.88 (C═O), 157.0 (NC=O), 98.8 (C-1′), 94.9 (C-8), 94.5 (C-1″), 83.8 (C-4), 74.9 (C-6), 74.3 (C-5), 70.7 (C-3″), 70.1 (C-2″), 69.8 (C-6), 68.8 (C-5″), 65.5 (C-5), 65.1 (C-4), 62.8 (C-6″), 60.1 (C-2′), 59.9 (C-7′), 58.4 (C-3), 58.0 (C-1), 57.6 (C-4″), 32.0 (C-2), 30.6 (C-3), 29.8 (C—NCH.sub.3), 20.9 (COCH.sub.3), 20.7 (COCH.sub.3); ESI-HRMS: m/z calcd. for C.sub.30H.sub.39N.sub.13NaO.sub.16 [M+Na].sup.+ 860.2535; found, 860.2522.

(85) TABLE-US-00001 TABLE 1 O5-ribosylated apramycin derivatives MIC (μg/mL) IC50 (μM) Compound 3′″ 5′″ WT AAC(3)-IV APH(3′)-I APH(3′)-II APH(3′)-III APH(3′)-VI Bac Mit Cyt apramycin — — 2-4 >128 1-2 4 1 4 0.08 68 71 DC146 OH — 8 32 4 4 1 8 0.09 215 321 DC131 OH OH 4 >32 64 8 4 4 0.11 295 319 DC177 OH Form. 8 >32 4 8 2 8 0.23 399 >500 DC201 OH NH2 8 16 2-4 4 1 4 0.12 113 81 DC214 OH N- 4 8-16 2 4 1 4 0.09 178 85 NH2- ethyl DC178 OH-ethyl OH 8 >32 >64 8 2 16 0.22 647 >500 DC124 NH2-ethyl OH 2 >32 64 2 0.5 4 0.06 57 181 DC185 NH2-ethyl NH2 1 >32 1 1 0.25 2 0.03 34 26 DC186 NH2-ethyl Form 2 >32 2 2 0.25 2 0.06 69 105 DC138 ring OH 2 >32 16 2 1-2 4 0.10 2.2 18 paromomycin ring OH 1-2 128 >128 >128 >128 >128 0.02 86 19

(86) Legend to Tables: GEN, gentamicin; AMK, amikacin; PLZ, plazomicin; APR, apramycin; AG212, Escherichia coli ATCC25922; AG215, Klebsiella pneumonia; AG220, Pseudomonas aeruginosa ATCC27853; AG225, Acinetobacter baumannii pittii; AG290, Enterobacter cloacae; AG192, SZ380, Mycobacterium smegmatis. MICs for AG192 have been determined in the presence of 0.5 μg/mL of ampicillin in the medium to mimic the synergistic effect of aminoglycoside and β-lactam antibiotics combination therapy in the treatment of Enterococcus infections in humans.

(87) TABLE-US-00002 TABLE 2 5-modified apramycin derivatives MIC (μg/mL) IC50 (μM) Compound Modification WT AAC(3)-IV apmA Bac Mit Cyt Apramycin — 2-4 >128 64 0.08 68 71 DC176 1-N-LHABA 2 4 16 0.11 166 326 DC169 5-deoxy 4 >32 16 0.06 45 42 DC161 5-epi 2 >32 2 0.05 20 17 DC191 5-epi-1-N-LHABA 2-4 4-8 8 0.20 98 87 DC170 5-deoxy-5-F 4 >32 32 0.06 62 74 DC168 5-deoxy-5-F epi 2 >32 4 0.05 30 28 DC167 6-O-(2OH-ethyl) 8 >32 >64 0.18 379 382 DC207 5-O-(3-hydroxypropyl) 8 >128 >128 0.60 >1000 >1000 DC213 5-O-(3-aminopropyl) 4 64 64-128 0.21 327 210 DC208 5-O-(2,3-dihydroxypropyl) 4-8 64 >128 0.21 434 >1000 DC209 5-O-(3-amino-2-hydroxypropyl) 2-4 8 64-128 0.04 146 105 DC212 5-O-(3-amino-2-hydroxypropyl) 4 0.10 158 112

(88) TABLE-US-00003 TABLE 3 6-modified apramycin derivatives MIC (μg/mL) IC50 (μM) Compound Modification WT AAC(3)-IV apmA Bac Mit Cyt Apramycin — 2-4 >128 64 0.08 68 71 DC167 6-O-(2OH-ethyl) 8 >32 >64 0.18 379 382

(89) TABLE-US-00004 TABLE 4 Antibiotic potency against bacterial reference strains MIC (μg/mL) Disk diffusion AG212 AG215 AG290 AG220 AG225 SZ380 ATCC19977 25 nmol E. coli K. pneumonia E. cloacae P. aeruginosa A. baumannii M. smegmatis M. abcessus N. gonorrhoeae GEN 0.5 0.25 0.25 0.5-1   0.5-1   2-4 AMK 2 1 1 2 2 2 PLZ 0.5-1   0.25-0.5  0.5 2-4 2 4 APR 4 2 4 4 4 2 <8 mm DC146 16 4 4 32 8 4 DC131 8 2 4 64 16 16 DC177 8 4 8 >64 16 2 16 DC201 4 2 2 4-8 4-8 0.25 1-2 DC214 2 1 1-2 8 8 0.25 2 DC178 8 4 8 >64 16 2 32 DC124 2 1-2 1-2 16-32 8 8 DC185 2 0.5-1   1 1-2 2 1 DC186 2-4 1 1-2 16-32 8 8 DC138 2 1 2 16 4 2 DC176 2-4 2 4 16 8 0.5 2 DC169 4 2 2 4 4 0.125 1 DC161 2 1 2 2 2 0.5 10 mm DC191 2 1-2 2 4 8 0.5 2 DC170 4 2 4 8 4-8 0.25 1 DC168 4 1 4 4 4 0.125 1 DC167 16 4 8 32 16 2 DC207 16 8 16 64 32 1 8 DC213 4-8 2 4-8 8 8 0.25 1 DC208 8 4 4 16-32 16 0.5 2 DC209 2-4 1 1 2-4 4 0.125 0.5-1   DC212 4 2 4 4 4

(90) TABLE-US-00005 TABLE 5 Antibacterial activity against representative clinical isolates AG042 AG003 AG173 AG039 MRSA AG033 AG001 AG055 E. coli E. coli AG163 MRSA AAC(6′)-I AG031 AG032 P. aer. E. coli E. coli AAC(3)- AAC(3)- E. coli AG038 AAC(6′)-I ANT(4′)-I P. aer. P. aer. APH(3′)-II WT WT II IV APH(3′)-I MRSA ANT(4′)-I APH(2′) APH(3′)-II APH(3′)-II AAC(6′)-I GEN 1 0.5 32-64 0.25-0.5  0.25-0.5  64 0.5 0.5 16 AMK 4 2-4 16-32 4 4 64 PLZ 2-4 2-4 2-4 2-4 2-4 2 4 4 16-32 APR  8-16 8 8 ≥128 4 4-8 8 8 8-16 8 16-32 DC146 16 16 16 128 8 16-32 16-32 16 64 64  64-128 DC131 16 16-32 16 16-32 8-16 64 64 64 64-128  64-128 128 DC177 8 16 8 >64 8 32 16-32 32 >32 >32 >32 DC201 4 2-4 16 DC214 2 16 4 8-16 DC178 32 16 16 32-64 8 16-32 32 32 >32 >32 >32 DC124 8 8 4-8 4 4-8   8-16 8 8 32-64  32-64 128 DC185 2 2 1-2 4 2 1 1 1 2 2 2 DC186 2 4 2 32 2 4 4-8 4-8 16 32 64 DC138 4 8 4 1-2 8 2-4 2-4 2 32-64  64 64 DC176 4 8 4 2-4 4 4-8 4-8 8 16 32 >32 DC169 4 4 4 32 2-4 2 4 8 8 16 DC161 4 4 4-8 64 4 4 2-4 4 4 8 DC191 8 4-8 4 DC170 8 4 8 64 4-8 4-8 8 8-16 16 32 DC168 8 4 4 128 2-4 2-4 4 8-16  8-16 32 DC167 16 16 16 >128 8-16 16-32 16-32 64 32-64  32-64  64-128 DC207 16 >128 32 128 DC213 16 128 4 16-32  DC208 8 >64  8-16 32 DC209 2 32 4 1-2 4 DC212 8 4 8

(91) TABLE-US-00006 TABLE 6 Activity against G1405-methylated 16S-rRNA Clinical isolates E. coli K. pneum. Enterob. Engineered E. coli AG153 AG269 AG302 A baum. E. coli E. coli E. coli E. coli E. coli E. coli AAC(3)-II AAC(3)-II AAC(3)-II AG227 pH430 AG103 pH424 pH425 pH426 pH427 APH(3′)-II AAC(6′)-I AAC(6′)-I APH(3′)-I WT armA armA rmtB rmtC rmtF rmtB rmtB rmtC armA GEN 0.25 >128 >128 >128 >128 >256 >256 >256 >256 AMK 1 >128 >128 >128 >128 >256 >256 >256 >256 PLZ 0.5 >32 APR 2-4 1-2 2-4 4 4 4 8 2 4 2 DC146 8 1 4 4 8 4 DC131 4 1 2 4 4 4 DC177 8  2-4 8 8 16 8 DC201 8 2 8 4 4  8-16 DC214 4 2 2 2 1-2 4-8 DC178 8 2 2 8 8 8 DC124 2 0.5 1 4 2 2 4 2 4 16 DC185 1 0.5-1  2 2 2 2 4 1 1 2 DC186 2 0.5-1  2 2 4 2 DC138 2 <0.125 1 1 1 1 DC176 2 0.25-0.5 2 2 4 4 4 2 2 2 DC169 4 1 2 4 4 4 DC161 2 2 2 2 2 DC191 2-4 2 4 2 2-4 4 DC170 4 2 2 4 4 4 DC168 2 1 2 2 2 2 DC167 8 4 8 16 16 16 DC207 8 4 8 8  8-16 16-32 DC213 4 4 32 4-8 4-8 4-8 DC208 4-8 2 8 4 4 8 DC209 2-4 2 2-4 1 2 2-4