METHOD FOR THE SYNTHESIS OF CYCLIC DEPSIPEPTIDES

Abstract

The present invention relates to a method for the synthesis of cyclic depsipeptides, in particular emodepside, from the open form.

Claims

1: A method of synthesizing a cyclic depsipeptide of formula (1) from a depsipeptide of formula (II): ##STR00089## wherein B is an amine protecting group and A is a carboxylic acid protecting group, whereby x and y are, independently of each other 0, 1 or 2, provided that x+y≥1, and each R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently hydrogen, straight-chain or branched C1-C8-alkyl, straight-chain or branched halogenated C1-C8 alkyl, hydroxy-C1-C6-alkyl, C1-C4-alkanoyloxy-C1-C6-alkyl, C1-C4-alkoxy-C1-C6-alkyl, aryl-C1-C4-alkyloxy-C1-C6-alkyl, mercapto-C1-C6-alkyl, C1-C4-alkylthio-C1-C6-alkyl, C1-C4-alkylsulphinyl-C1-C6-alkyl, C1-C4-alkylsulphonyl-C1-C6-alkyl, carboxy-C1-C6-alkyl, C1-C4-alkoxycarbonyl-C1-C6-alkyl, C1-C4-arylalkoxycarbonyl-C1-C6-alkyl, carbamoyl-C1-C6-alkyl, amino-C1-C6-alkyl, C1-C4-alkylamino-C1-C6-alkyl, C1-C4-dialkylamino-C1-C6-alkyl, guanidino-C1-C6-alkyl, C1-C4-alkoxycarbonylamino-C1-C6-alkyl, 9-fluorenylmethoxycarbonyl(Fmoc)amino-C1-C6-alkyl, C2-C8-alkenyl, C3-C7-cycloalkyl, C3-C7-cycloalkyl-C1-C4-alkyl, benzyl, substituted benzyl, phenyl, or phenyl-C1-C4-alkyl which may optionally be substituted by radicals from the group consisting of halogen; the method comprising: deprotecting the amine group that is protected by B to obtain a deprotected amine group; deprotecting the carboxylic acid that is protected by A to obtain a deprotected carboxylic acid group; and condensing the deprotected amine group and the deprotected carboxylic acid group to obtain the cyclic depsipeptide of formula (I).

2: The method of claim 1, wherein x is 1, y is 1, R1, R4, R7 and R10 are each methyl, R6 and R12 are each methyl, R5 and R11 are, independently of each other, straight-chain or branched C1-C4-alkyl or straight-chain or branched halogenated C1-C4-alkyl and R3 and R9 are, independently of each other, benzyl or substituted benzyl.

3: The method of claim 1, wherein one or both of R3 and R9 is p-morpholino substituted benzyl.

4: The method of claim 1, wherein the depsipeptide of formula (II) is a depsipeptide of formula (IIa): ##STR00090## wherein Y is an amine protecting group and X is a carboxylic acid protecting group, the method comprising the steps of: deprotecting the amine group that is protected by Y in the presence of an acid to obtain a deprotected amine group; deprotecting the carboxylic acid that is protected by X via hydrogenolysis to obtain a deprotected carboxylic acid group; and condensing the deprotected amine group and the carboxylic acid group to obtain the cyclic depsipeptide of formula (I).

5: The method of claim 4, wherein X is a substituted or unsubstituted —CH.sub.2-Aryl group.

6: The method of claim 4, wherein X is selected from the group consisting of benzoyl (Bn), 4-methoxy-benzoyl (PMB), 3,4-dimethoxybenzoyl (DPMB), 4-phenyl-benzoyl (PPB), 2-naphthylmethyl (Nap), and Benzyloxymethyl acetal (BOM).

7: The method of claim 4, wherein Y is t.-Butyloxycarbonyl (BOC).

8: The method of claim 4, wherein the method further comprises obtaining the depsipeptide of formula (IIa) from precursors of formulas (IV) and (III): ##STR00091## wherein PG2 is an amine protecting group and PG3 is a carboxylic acid protecting group, and by: deprotecting the amine group that is protected by PG2 in the precursor of formula (IV) in the presence of a base to obtain a deprotected amine group; deprotecting the carboxylic acid that is protected by PG3 in the precursor of formula (III) in the presence of an acid to obtain a deprotected carboxylic acid group; and condensing the deprotected amine group and the carboxylic acid group to obtain the depsipeptide of formula (IIa).

9: The method of claim 8, wherein the method further comprises obtaining the precursor of formula (IV) from precursors of formulas (VI) and (V): ##STR00092## wherein PG4 is an amine protecting group, by: deprotecting the amine group that is protected by PG4 in the precursor of formula (VI) in the presence of a base to obtain a deprotected amine group; and condensing the deprotected amine group of the precursor of formula (VI) from (i) and the carboxylic acid group of the precursor of formula (V) to obtain the precursor of formula (IV).

10: The method of claim 8, wherein the method further comprises obtaining the precursor of formula (III) from precursors of formulas (VIII) and (VII): ##STR00093## by: deprotecting the amine group that is protected by PG5 in the precursor of formula (VII) in the presence of a base to obtain a deprotected amine group; and condensing the deprotected amine group of the precursor of formula (VII) and the carboxylic acid group of the precursor of formula (VIII) to obtain the precursor of formula (III).

11: The method of claim 9, wherein the method further comprises obtaining the precursor of formula (VI) by esterifying a precursor of formula (IX) with X-LG: ##STR00094## wherein LG is a leaving group.

12: The method of claim 10, wherein the method further comprises obtaining the precursor of formula (VII) by esterifying a precursor of formula (X) with PG3-OH: ##STR00095##

13: The method of claim 12, wherein PG3 is X.

14: The method of claim 8, wherein the precursors of formulas (III) and (IV) are identical.

15: The method of claim 1, wherein R3 and R9 are identical, R1 and R7 are identical, R2 and R8 are identical, R4 and R10 are identical, R5 and R11 are identical, and R6 and R12 are identical.

16: The method of claim 1, wherein the depsipeptide of formula (II) is a depsipeptide of formula (IIb): ##STR00096## wherein TAG is a carboxylic acid protecting group comprising a moiety Aryl-O—(CH.sub.2).sub.n— wherein Aryl is an aromatic moiety and n≥13, wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently hydrogen, straight-chain or branched C1-C8-alkyl, straight-chain or branched halogenated C1-C8-alkyl, hydroxy-C1-C6-alkyl, C1-C4-alkanoyloxy-C1-C6-alkyl, C1-C4-alkoxy-C1-C6-alkyl, aryl-C1-C4-alkyloxy-C1-C6-alkyl, mercapto-C1-C6-alkyl, C1-C4-alkylthio-C1-C6-alkyl, C1-C4-alkylsulphinyl-C1-C6-alkyl, C1-C4-alkylsulphonyl-C1-C6-alkyl, carboxy-C1-C6-alkyl, C1-C4-alkoxycarbonyl-C1-C6-alkyl, C1-C4-arylalkoxycarbonyl-C1-C6-alkyl, carbamoyl-C1-C6-alkyl, amino-C1-C6-alkyl, C1-C4-alkylamino-C1-C6-alkyl, C1-C4-dialkylamino-C1-C6-alkyl, guanidino-C1-C6-alkyl, C1-C4-alkoxycarbonylamino-C1-C6-alkyl, tert-butoxycarbonylaminobutyl, 9-fluorenylmethoxycarbonyl(Fmoc)amino-C1-C6-alkyl, C2-C8-alkenyl, C3-C7-cycloalkyl, C3-C7-cycloalkyl-C1-C4-alkyl, benzyl, substituted benzyl, phenyl, phenyl-C1-C4-alkyl, hydroxyl, C1-C4-alkoxy or C1-C4-alkyl, the method comprising: deprotecting the amine group that is protected by PG1 in the presence of a base to obtain a deprotected amine group; deprotecting the carboxylic acid that is protected by TAG in the presence of an acid to obtain a deprotected carboxylic acid group; and condensing the deprotected amine group and the deprotected carboxylic acid group to obtain the cyclic depsipeptide of formula (I).

17: The method of claim 16, wherein PG1 is 9-fluorenylmethoxycarbonyl (Fmoc), t-butyl carbamate (Boc), benzyl carbamate (Z), acetamide, trifluoroacetamide, phthalimide, benzyl (Bn), triphenylmethyl (Tr), benzylidene, or p-toluenesulfonamide (Ts) and TAG is: ##STR00097## wherein m is ≥15 to ≤25, p is ≥8 to ≤18 and q is ≥15 to ≤25.

18: The method of claim 16, wherein the method further comprises obtaining the depsipeptide of formula (IIb) from precursors of formulas (IVb) and (IIIb): ##STR00098## by: deprotecting the amine group that is protected by PG2 in the precursor of formula (IVb) in the presence of a base to obtain a deprotected amine group; deprotecting the carboxylic acid that is protected by PG3 in the precursor of formula (IIIb) in the presence of an acid to obtain a deprotected carboxylic acid group; and (iii) condensing the deprotected amine group and the carboxylic acid group to obtain the depsipeptide of formula (IIb).

19: The method of claim 18, wherein the method further comprises obtaining the precursor of formula (IVb) from precursors of formulas (VIb) and (Vb): ##STR00099## wherein obtaining the precursor of formula (IVb) comprises: (i) deprotecting the amine group that is protected by PG4 of formula (VIb) in the presence of a base to obtain a deprotected amine group; and (ii) condensing the deprotected amine group of the precursor of formula (VIb) and the carboxylic acid group of the precursor of formula (Vb) to obtain the precursor (IVb).

20: The method of claim 18, wherein the method further comprises obtaining the precursor of formula (IIIb) from precursors of formulas (VIIIb) and (VIIb): ##STR00100## by: deprotecting the amine group that is protected by PG5 in formula (VIIb) in the presence of a base to obtain a deprotected amine group; and condensing the deprotected amine group of the precursor of (VIIb) and the carboxylic acid group of the precursor of formula (VIIIb) to obtain the precursor (IIIb).

21: The method of claim 19, wherein the method further comprises obtaining the precursor of formula (VIb) by esterifying a precursor of formula (IXb) with TAG-OH: ##STR00101##

22. The method of claim 20, wherein the method further comprises obtaining the precursor of formula (VIIb) by esterifying a precursor of the formula (Xb) with PG3-OH: ##STR00102##

23: The method of claim 22, wherein PG3 is TAG.

24: The method of claim 16, wherein the method further comprises purifying a TAG-bearing molecule by precipitation in methanol.

25: The method of claim 16, wherein at least one step of the reaction steps in which TAG-protected carboxylic acid groups are deprotected is followed by precipitation of cleaved TAG-OH in methanol and removal of the precipitate by filtration, thereby purifying the crude reaction product.

26: The method of claim 1, wherein the depsipeptide of formula (II) is selected from the group consisting of: ##STR00103## ##STR00104## ##STR00105## ##STR00106## ##STR00107## ##STR00108## ##STR00109## ##STR00110## ##STR00111## ##STR00112## ##STR00113## ##STR00114## ##STR00115## ##STR00116## wherein in formulas (II-11) to (II-14) -LINK- is selected from the group consisting of ##STR00117## ##STR00118## wherein X1 can be C, N, S, O, X2 and X3 can be C or N; ##STR00119## wherein X1 can be C, N, S, O, X2, X3 and X4 can be C or N; and ##STR00120## wherein X1, X2, X3 and X4 can be C or N; and wherein R13 is selected from SO.sub.2NH(CH.sub.3), SO.sub.2NH.sub.2, OC(O)CH.sub.3, CF.sub.3 or one the following lactone structures: ##STR00121##

27: A method for the synthesis of cyclic depsipeptides according to the general formula (1) from depsipeptides according to the general formula (IIc): ##STR00122## comprising Providing a mixture of compound (IIc) and a base in a solvent having an E.sub.T(30)-value of ≥30 and ≤43; adding by slow addition of a solution of a coupling agent in the solvent to form the cyclic depsipeptide (I) whereby x and y are independently 0, 1 or 2, provided that x+y≥1, and each R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently hydrogen, straight-chain or branched C1-C8-alkyl, straight-chain or branched halogenated C1-C8 alkyl, hydroxy-C1-C6-alkyl, C1-C4-alkanoyloxy-C1-C6-alkyl, C1-C4-alkoxy-C1-C6-alkyl, aryl-C1-C4-alkyloxy-C1-C6-alkyl, mercapto-C1-C6-alkyl, C1-C4-alkylthio-C1-C6-alkyl, C1-C4-alkylsulphinyl-C1-C6-alkyl, C1-C4-alkylsulphonyl-C1-C6-alkyl, carboxy-C1-C6-alkyl, C1-C4-alkoxycarbonyl-C1-C6-alkyl, C1-C4-arylalkoxycarbonyl-C1-C6-alkyl, carbamoyl-C1-C6-alkyl, amino-C1-C6-alkyl, C1-C4-alkylamino-C1-C6-alkyl, C1-C4-dialkylamino-C1-C6-alkyl, guanidino-C1-C6-alkyl, C1-C4-alkoxycarbonylamino-C1-C6-alkyl, 9-fluorenylmethoxycarbonyl(Fmoc)amino-C1-C6-alkyl, C2-C8-alkenyl, C3-C7-cycloalkyl, C3-C7-cycloalkyl-C1-C4-alkyl, benzyl, substituted benzyl, phenyl, or phenyl-C1-C4-alkyl which may optionally be substituted by radicals from the group consisting of halogen.

28: The method according to claim 27, whereby the E.sub.T(30)-value of the solvent is ≥34 and ≤39.

29: The method according to claim 27, wherein the solution of the coupling agent is added at a rate of ≤2 (mol)-% per minute.

30: The method according to claim 27, wherein the coupling agent is selected from the group consisting of PyBOP (benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate), BOP ((Benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate), DEPBT (3-(diethoxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one), HATU (1-[Bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxid hexafluorophosphate), HBTU (2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate) and T3P® (Propylphosphonic anhydride, 2,4,6-Tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide, PPACA).

31: The method according to claim 27, wherein the ratio of base to compound (IIb) prior to the reaction (in mol:mole) is ≥2:1 to ≤10:1.

32: The method according to claim 27, wherein the ratio of coupling agent to compound (IIb) prior to the reaction (in mol:mole) is ≥1:1 to ≤5:1.

33: The method according to claim 27, wherein during the addition of the coupling agent the temperature is kept ≤25° C.

34: A linear or cyclic depsipeptide selected from the group consisting of one of the general formulas (II-1) to (II-14b) or (I-1) to (I-9) or a pharmaceutically or veterinarily acceptable salt thereof: ##STR00123## ##STR00124## ##STR00125## ##STR00126## ##STR00127## ##STR00128## ##STR00129## ##STR00130## ##STR00131## ##STR00132## ##STR00133## ##STR00134## ##STR00135## ##STR00136## ##STR00137## ##STR00138## ##STR00139## wherein in formulas (II-11a) to (II-14b) and (I-1) to (I-9), respectively: -LINK- is selected from: ##STR00140## and R13 is SO.sub.2NH(CH.sub.3), SO.sub.2NH.sub.2, OC(O)CH.sub.3, CF.sub.3 or one the following lactone structures: ##STR00141##

Description

EXAMPLES

[0123] The present invention will be further described with reference to the following examples without wishing to be limited by them.

[0124] 1. General Method

[0125] The starting building blocks were prepared from commercial available reagents. Unless otherwise noted, reagents and solvents were purchased at highest commercial quality and used without further purification. Methanol and dry toluene, CH.sub.2Cl.sub.2 were purchased from Kanto Chemical Co., Inc. All reactions were monitored by thin-layer chromatography (TLC) using Merck silica gel 60 F254 pre-coated plates (0.25 mm). Flash chromatography was carried out with Kanto Chemical silica gel (Kanto Chemical, silica gel 60N, spherical neutral, 0.040-0.050 mm, Cat.-No. 37563-84). .sup.1H and .sup.13C NMR spectra were recorded on JEOL JNM-ECA-500 (500 MHz for .sup.1H-NMR and 125 MHz for .sup.13C-NMR). Chemical shifts are expressed in ppm downfield from the internal solvent peaks for CDCl.sub.3 (.sup.1H; δ=7.26 ppm, .sup.13C; δ=77.0 ppm), CD.sub.3OD (.sup.1H; δ=3.31 ppm, .sup.13C; δ=49.0 ppm) and J values are given in Hertz. The following abbreviations were used to explain the multiplicities: s=singlet, d=doublet, t=triplet, q=quartet, dd=double doublet, ddd=double double doublet, dt=double triplet, dq=double quartet, m=multiplet, br=broad. All infrared spectra were measured on a Horiba FT-210 spectrometer. High- and Low-resolution mass spectra were measured on a JEOL JMS-AX505 HA, JEOL JMS-700 MStation and JEOL JMS-T100LP. Optical rotations were measured by using JASCO P-1010 polarimeter. Melting points were measured on a YANACO MP-500P or OptiMelt (Stanford Research Systems) apparatus.

[0126] General Method for Fmoc Deprotection

[0127] Fmoc protected substrate was dissolved into 5% piperidine/CH.sub.2Cl.sub.2 (generally 0.05 M for substrate) at room temperature and solution was stirred for 3 h. The reaction mixture was subsequently cooled to −5° C. and MeOH was added (five times excess of reaction solution). The resulting heterogeneous solution was stirred for further 30 min at −5° C., and the colorless precipitate was filtered and washed with additional MeOH to afford corresponding amine as a colorless powder.

[0128] General Method for the Cleavage of TAGa Function

[0129] Tagged substrates with TAGa dissolved into 50% TFA/CH2Cl2 (0.05 M for substrate) at room temperature and solution was stirred for generally 1 h. The reaction mixture was subsequently concentrated with toluene (×3) to remove TFA. To a flask was then added CH2Cl2 at −5° C., followed MeOH was added (five times excess of CH2Cl2). The resulting heterogeneous solution was stirred for further 30 min at −5° C., and the colorless precipitate was filtered off and washed with additional MeOH. The combined filtrates were concentrated in vacuo. To the resulting product was added 4 M HC/Dioxane (0.05 M for product) and concentrated with toluene (×3) to afford corresponding carboxylic acid as a generally brown oil. The crude was used next reaction without further purification.

[0130] product) and concentrated with toluene (×3) to afford corresponding carboxylic acid as a generally brown oil. The crude was used next reaction without further purification.

[0131] 2. Synthesis of Emodepside

[0132] In the following the synthesis of emodepside is described, using the compound Benzyl (R)-2-hydroxy-3-(4-morpholinophenyl)propanoate (named EMD-8) which is synthesized from p-fluroro benzaldehyd according to the scheme of FIG. 1. Using this compound, emodepside is synthesized according to the scheme of FIG. 2.

##STR00037##

[0133] 4-Morpholinobenzaldehyde (EMD-22): Into a 100 L reactor, was placed a solution of 4-fluorobenzaldehyde (EMD-21, 3.6 kg, 29.0 mol, 1.0 eq) in 1-methyl-2-pyrrolidine (36 L, 10.0V), morphline (7.6 kg, 87 mol, 3.0 eq), K.sub.2C03 (10.0 kg, 72.5 mol, 2.5 eq). The resulting mixture was stirred at least for 6 h at 125˜130° C. The reaction was monitored by TLC until no EMD-21. The reaction mixture was diluted with ethyl acetate (18 L, 5 V), H.sub.2O (72 L, 20 V), and separated. The water phase was extracted with ethyl acetate (18 L×2) and combined the organic phase, and washed with H.sub.2O (36.0 L×3). The organic extracts were concentrated under vacuum at below 45° C. until no distillate drops out. The residue was eluted with heptane/ethyl acetate (5:1, v/v, 7.2 L) and concentrated under vacuum at below 45° C. Then, to the above residue was added heptane/ethyl acetate (5:1, v/v, 21.6 L) at 20˜25° C. The solution was stirred at 20˜25° C. for 16 h. The mixture was filtered, and the filter cake was washed with heptane (7.3 L). The solids were dried under vacuum at 40˜45° C. This resulted in 4.67 kg (84.8%) of 4-Morpholinobenzaldehyde (EMD-22) as a yellow solid. MS (ES, m/z): 192 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 9.74 (s, 1H), 7.74 (d, J=8.1 Hz, 2H), 7.07 (d, J=8.4 Hz, 2H), 3.75-3.74 (m, 4H), 3.35-3.33 (m, 4H).

##STR00038##

[0134] (Z)-2-methyl-4-(4-morpholinobenzylidene)oxazol-5(4H)-one (EMD-22B): Into a 100 L reactor, was placed a solution of N-acetylglycine (1.22 kg, 10.46 mol, 1.0 eq) in tetrahydrofuran (20 L, 10 V), acetic anhydride (3.2 kg, 31.38 mol, 3.0 eq), zinc(II) chloride (1.48 kg, 10.46 mol, 1.0 eq). The resulting mixture was stirred at 70° C. for 1 h and EMD-22 (2.0 kg, 10.46 mol, 1.0 eq) was added. Then, the mixture was stirred at 70° C. for another 16 h and monitored by LCMS. After cooling to 20˜25° C., H.sub.2O (40 L) was added. Then, the mixture was stirred at 0˜5° C. for 3 h and filtered. The filter cake was washed with H.sub.2O (10 L), and dried under vacuum at 40˜45° C. This resulted in 2.29 kg (80.4%) of (Z)-2-methyl-4-(4-morpholinobenzylidene)oxazol-5(4H)-one (EMD-22B) as a brown solid. MS (ES, m/z): 273 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.84 (s, 1H), 7.47 (d, J=9.0 Hz, 2H), 7.02 (d, J=9.1 Hz, 2H), 3.74-3.71 (m, 4H), 3.32-3.27 (m, 4H).

##STR00039##

[0135] (E)-2-hydroxy-3-(4-morpholinophenyl)acrylic acid (EMD-23): Into a 50 L reactor, was placed a solution of EMD-22B (2.2 kg, 8.08 mol, 1.0 eq) in 1,4-dioxane (8.8 L, 4.0 V), HCl (8.8 L, 4.0 V) at 20˜25° C. The resulting mixture was stirred at 80° C. for 3 h and monitored by LCMS. After cooling to 0˜10° C., the mixture was stirred at 0˜10° C. for 16 h and filtered. The fiter cake was dried under vacuum at 40˜45° C., The crude product was eluted with H.sub.2O (4.4 L) and stirred at 0˜10° C. for 2 h. The mixture was fitered, and the filter cake was dried under vacuum at 40˜45° C. This resulted in 1.17 kg (56.0%) of (E)-2-hydroxy-3-(4-morpholinophenyl)acrylic acid (EMD-23) as a slater solid. MS (ES, m/z): 250 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.66 (d, J=8.5 Hz, 2H), 6.97 (d, J=8.6 Hz, 2H), 6.35 (s, 1H), 4.05 (s, 1H, —OH), 3.77-3.74 (m, 4H), 3.19-3.16 (m, 4H).

##STR00040##

[0136] (R)-2-hydroxy-3-(4-morpholinophenyl)propanoic acid (EMD-24): Into a 2 L round-bottom flask purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-23 (66.0 g, 0.26 mol, 1.0 eq) in N,N-dimethylformamide (660 mL, 10.0 V), Et.sub.3N (107.2 g, 1.06 mol, 4.0 eq), RuCl(R,R)-TsDPEN (1.69 g, 0.0026 mol, 0.01 eq) at 20˜25° C. To the above mixture was added formic acid (36.59 g, 0.79 mol, 3.0 eq) dropwise for 2 h at 20˜25° C. under N.sub.2 atmosphere. Then, the mixture was stirred at 20˜25° C. and monitored by LCMS. The reaction was noted for M1, which was used for next step without further purification.

##STR00041##

[0137] Benzyl (R)-2-hydroxy-3-(4-morpholinophenyl)propanoate (EMD-8): To a mixture (M1) was added K.sub.2CO.sub.3 (109.0 g, 0.78 mol, 3.0 eq) and dropwise benzyl bromide (54.0 g, 0.32 mol, 1.2 eq) at 20˜25° C. for 1 h. Then, the mixture was stirred at 55˜60° C. for another 16 h. The reaction mixture was diluted with ethyl acetate (330 mL, 5 V), H.sub.2O (1.2 L, 20 V), and separated. The water phase was extracted with ethyl acetate (330 mL×2) and combined the organic phase, and washed with H.sub.2O (660 mL×3). The organic extracts were concentrated under vacuum at below 45° C. until no distillate drops out. The residue was eluted with heptane/ethyl acetate (3:1, v/v, 132 mL) and concentrated under vacuum at below 45° C. Then, to the above residue was added heptane/ethyl acetate (3:1, v/v, 264 mL) at 20˜25° C. The mixture was filtered, and the filter cake was washed with heptane (132 mL). The solids were dried under vacuum at 40˜45° C. This resulted in 52 g (58%) of benzyl (R)-2-hydroxy-3-(4-morpholinophenyl)propanoate (EMD-8) as a yellow solid. MS (ES, m/z): 342 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.40-7.27 (m, 5H), 7.05 (d, J=8.1 Hz, 2H), 6.82 (d, J=8.1 Hz, 2H), 5.17 (s, 2H), 4.24 (t, J=7.5 Hz, 1H), 3.74-3.71 (m, 4H), 3.06-3.03 (m, 4H), 2.90-2.73 (m, 2H).

##STR00042##

[0138] (R)-1-(benzyloxy)-3-(4-morpholinophenyl)-1-oxopropan-2-yl-N-(tert-butoxycarbonyl)-N-methyl-L-leucinate (EMD-9B): Into a 50 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-8 (1.96 kg, 5.75 mol, 1.0 eq) in dichloromethane (14.1 L, 10.V), N-(tert-butoxycarbonyl)-N-methyl-L-leucine (1.41 kg, 5.75 mol, 1.0 eq), DMAP (0.77 kg, 6.32 mol, 1.1 eq), EDCI (1.21 kg, 6.32 mol, 1.1 eq) at 20˜25° C. The mixture was stirred at this temperature for at least 3 h and monitored by LCMS. The mixture was concentrated at below 40° C. until no distillate drops out. The residue was dissolved in MTBE (14.1 L) and HCl (aq, 1N, 14.1 L) and filtered. The organic was washed with HCl (aq, 1N, 14.1 L), NaHCO.sub.3 (sat, 14.1 L×2), and concentrated at below 40° C. until no distillate drops out. Then the residue was resolved in heptane/MTBE (28.2 L, 8:1, v/v), and concentrated at below 40° C. until no distillate drops out. To the above residue was added heptane/MTBE (15.5 L, 8:1, v/v) at 20˜25° C. and seed crystal (0.2%, w/w), and kept stirring for overnight at 20˜25° C. The mixture was filtered; the filter cake was washed with heptane (7.0 L). The solids were dried under vacuum at 4045° C. This resulted in 2.56 kg (78.3%) of (R)-1-(benzyloxy)-3-(4-morpholinophenyl)-1-oxopropan-2-yl-N-(tertbutoxycarbonyl)-N-methyl-L-leucinate (EMD-9B) as a light yellow solid. MS (ES, m/z): 569 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.38-7.26 (m, 5H), 7.10 (d, J=8.2 Hz, 2H), 6.96 (d, J=8.1 Hz, 2H), 5.25-5.22 (m, 1H), 5.12-5.10 (m, 2H), 4.07-3.99 (m, 1H), 3.79-3.76 (m, 4H), 3.19-2.97 (m, 6H), 2.57 (s, 3H), 1.42-1.34 (m, 11H), 1.24-1.15 (m, 1H), 0.88-0.82 (m, 6H).

##STR00043##

[0139] (R)-2-((N-(tert-butoxycarbonyl)-N-methyl-L-leucyl)oxy)-3-(4-morpholinophenyl)propanoic acid (EMD-10B): Into a 50 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-9B (400 g, 0.7 mol, 1.0 eq) in EtOH (4.0 L, 10.0V) at 20˜25° C., The reactor was evacuated and flushed with nitrogen for three times and Pd/C (28.0 g, 7% w/w) was added. Then the reactor was evacuated and flushed with nitrogen for three times again, and kept hydrogen bubbling underneath the reaction mixture surface. The mixture was stirring for at least for 4 h at 20˜25° C. and monitored by HPLC. After the reaction completing, the hydrogen bubbling was cut off. The mixture was filtered through celite (2.0 kg) and filter cake was rinsed with EA (0.8 L), and the filtrate was concentrated at below 40° C. until no distillate drops out. This resulted in 317.7 g (94.4%) of (R)-2-((N-(tert-butoxycarbonyl)-N-methyl-L-leucyl)oxy)-3-(4-morpho-linophenyl)propanoic acid (EMD-10B) as a dark yellow oil; MS (ES, m/z): 479 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.10 (d, J=8.4 Hz, 2H), 6.85 (d, J=8.7 Hz, 2H), 5.03-5.02 (m, 1H), 4.81-4.53 (m, 1H), 3.73 (t, J=7.2 Hz, 4H), 3.05 (t, J=7.2 Hz, 4H), 2.96-2.90 (m, 1H), 2.63 (s, 3H), 1.42-1.16 (m, 12H), 0.89-0.84 (m, 6H).

##STR00044##

[0140] (R)-1-(benzyloxy)-1-oxopropan-2-yl methyl-L-leucinate (EMD-12B): Into a 10 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of N-(tert-butoxycarbonyl)-N-methyl-L-leucine (240.3 g, 0.98 mol, 1.0 eq) in THF (3.9 L, 16 v), benzyl (S)-2-hydroxypropanoate (176.5 g, 0.98 mol, 1.0 eq), triphenylphosphine (385.1 g, 1.47 mol, 1.5 eq) at 20˜25° C. After cooling to below 10° C., diisopropyl azodiformate (297 g, 1.47 mol, 1.5 eq) was added dropwise with stirring at below 10° C. Then, warming up to 20˜25° C. and stirring for at least 2 h. The reaction was monitored by HPLC until benzyl (S)-2-hydroxypropanoate less than or equal to 0.5%. The resulting mixture was diluted with ethyl acetate (3.9 L) and washed with NaHCO.sub.3 (sat, 3.9 L×2), brine (3.9 L×2). The organic phase was concentrated at below 40° C. until no distillate drops out. The residue was exchanged with tert-Butyl methyl ether (240 mL×2), concentrated below 40° C. until no distillate drops out, and slurryed with tert-butyl methyl ether (960 mL) for at least 3 h. The mixture was filtered and the filter cake was washed with tert-butyl methyl ether (240 mL). The filtrate was concentrated at below 40° C. until no distillate drops out.

[0141] This resulted in crude product of (R)-1-(benzyloxy)-1-oxopropan-2-yl N-(tert-butoxycarbonyl)-N-methyl-L-leucinate (EMD-1B) as a yellow oil, which was used for next step without further purification. Into a 10 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-1B in HCl/EA (1.2 L, 5.0 eq) below 25° C. The mixture was stirred for at least 1 h at 20˜25° C. and monitored by HPLC until EMD-1B less than or equal to 0.5%. The solution was concentrated at below 40° C. until no distillate drops out. The residue was exchanged with tert-Butyl methyl ether (240 mL×2), concentrated below 40° C. until no distillate drops out, and resolved with tert-butyl methyl ether (1.92 L). Then, the seed crystal (0.1%, w/w) was added and stirred for at least 5 h at 20˜25° C. The mixture was filtered and the filter cake was washed with tert-butyl methyl ether (0.24 L). The solid was dried under vacuum at 40±5° C. and 270 g of crude product was obtained as a white solid. The solid was dissolved in ethyl acetate (810 mL) by warming up to 40±5° C. and tert-butyl methyl ether (4.05 L) was added. Subsequently, cooling down to 20˜25° C. and the seed crystal (0.1%. w/w) was added. The mixture was stirred for at least 5 h at 20˜25° C., filtered, the filter cake was washed with tert-butyl methyl ether (0.24 L). The solid was dried under vacuum at 40±5° C. This resulted in 226.7 g (67.3%, two steps) of (R)-1-(benzyloxy)-1-oxopropan-2-yl methyl-L-leucinate (EMD-12B) as a white solid. MS (ES, m/z): 308 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.41-7.35 (m, 5H), 5.28 (q, J=7.1 Hz, 1H), 5.20 (s, 2H), 2.51 (s, 3H), 1.77-1.71 (m, 3H), 1.50-1.48 (m, 3H), 0.90-0.87 (m, 6H).

##STR00045##

[0142] (R)-1-(benzyloxy)-1-oxopropan-2-yl N—((R)-2-((N-(tert-butoxycarbonyl)-N-methyl-L-leuc yl)oxy)-3-(4-morpholinophenyl)propanoyl)-N-methyl-L-leucinate (EMD-13B): Into a 10 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-10B (275.0 g, 0.57 mol, 1.0 eq) in ethyl acetate (2.2 L, 8.0 V), EMD-12B (197.7 g, 0.57 mol, 1.0 eq), N,N-diisopropylethylamine (372.2 g, 2.88 mol, 5.0 eq) at 20˜25° C. After cooling to 10˜20° C., propylphosphonic anhydride (916.4 g, 1.44 mol, 2.5 eq) was added dropwise with stiring at below 25° C. Then, the mixture was stirred at 20˜25° C. for at least 2.5 h and monitored by HPLC until EMD-12B less than or equal to 1.0%. The solution was diluted with heptane (2.75 L) at 0˜10° C. and quenched slowly with HCl (aq, 1.0N, 2.75 L). The organic phase was washed HCl (aq, 1.0N, 2.75 L), NaHCO.sub.3 (sat, 2.75 L×2), and concentrated at below 40° C. until no distillate drops out. This resulted in 429.8 g (97.4%) of (R)-1-(benzyloxy)-1-oxopropan-2-yl N—((R)-2-((N-(tert-butoxycarbonyl)-N-methyl-L-leucyl)oxy)-3-(4-morpholinophenyl)propanoyl)-N-methyl-L-leucinate (EMD-13B) as a yellow thick oil. MS (ES, m/z): 768 (M+H);

##STR00046##

[0143] (R)-1-(benzyloxy)-1-oxopropan-2-yl-N-methyl-N—((R)-2-((methyl-L-leucyl)oxy)-3-(4-morphol-inophenyl)propanoyl)-L-leucinate (EMD-14B): Into a 5 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-13B (245 g, 0.32 mol, 1.0 eq) in HCl/EA (735, 3.0 V) below 25° C. The mixture was stirred for at least 1 h at 20˜25° C. and monitored by HPLC until EMD-13B was less than or equal to 0.5%. The resulting solution was concentrated at below 40° C. until no distillate drops out and exchanged with ethyl acetate (245 mL×2) at below 40° C. The residue was dissolved in ethyl acetate (735 mL) and N,N-diisopropylethylamine (245 g) was added at 20˜25° C. The mixture was washed with NaHCO.sub.3 (sat, 735 mL×2). The organic was concentrated at below 40° C. until no distillate drops out. This resulted in 186.9 g (89.9%) of (R)-1-(benzyloxy)-1-oxopropan-2-yl-N-methyl-N—((R)-2-((methyl-L-leucyl)oxy)-3-(4-morphol-inophenyl)propanoyl)-L-leucinate (EMD-14B) as a yellow oil. MS (ES, m/z): 668 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.41-7.32 (m, 5H), 7.17 (d, J=8.5 Hz, 2H), 6.86 (d, J=8.6 Hz, 2H), 5.50-5.47 (m, 1H), 5.20-5.04 (m, 4H), 4.23-3.99 (m, 1H), 3.74-3.72 (m, 4H), 3.09-2.76 (m, 10H), 2.22-1.99 (m, 3H), 1.63-1.35 (m, 5H), 1.29-1.16 (m, 4H), 0.97-0.70 (m, 12H).

##STR00047##

[0144] (6S,9R,12S,15R)-6,12-diisobutyl-2,2,5,11,15-pentamethyl-9-(4-morpholinobenzyl)-4,7,10,13-tetraoxo-3,8,14-trioxa-5,11-diazahexadecan-16-oic acid (EMD-15B): Into a 10 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-13B (274.2 g, 0.36 mol, 1.0 eq) in EtOH (2.8 L, 10.0V) at 20˜25° C., The reactor was evacuated and flushed with nitrogen for three times and Pd/C (19.2 g, 7% w/w) was added. Then the reactor was evacuated and flushed with nitrogen for three times again, and kept hydrogen bubbling underneath the reaction mixture surface. The mixture was stirring for at least for 4 h at 20˜25° C. and monitored by HPLC. After the reaction completing, the hydrogen bubbling was cut off. The mixture was filtered through celite (2.0 kg) and filter cake was rinsed with ethyl acetate (0.56 L), and the filtrate was concentrated at below 40° C. until no distillate drops out. This resulted in 237.4 g (98.0%) of (6S,9R,12S,15R)-6,12-diisobutyl-2,2,5,11,15-pentamethyl-9-(4-morpholinobenzyl)-4,7,10,13-tetraoxo-3,8,14-trioxa-5,11-diazahexadecan-16-oic acid (EMD-15B) as a yellow oil; MS (ES, m/z): 678 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.15 (d, J=8.4 Hz, 2H), 6.85 (d, J=8.3 Hz, 2H), 5.52-5.40 (m, 1H), 5.09-5.02 (m, 1H), 4.91-4.53 (m, 2H), 3.74-3.72 (m, 4H), 3.15-3.04 (m, 5H), 2.94-2.86 (m, 4H), 2.65-2.64 (m, 3H), 1.43-1.28 (m, 16H), 0.93-0.77 (m, 12H).

##STR00048##

[0145] (R)-1-(benzyloxy)-1-oxopropan-2-yl N-methyl-N-((6S,9R,12S,15R,18S,21R)-6,12,18-triiso butyl-2,2,5,11,15,17-hexamethyl-9,21-bis(4-morpholinobenzyl)-4,7,10,13,16,19-hexaoxo-3,8,14,20-tetraoxa-5,11,17-triazadocosan-22-oyl)-L-leucinate (EMD-16B): Into a 10 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-15B (147.6 g, 0.22 mol, 1.0 eq) in ethyl acetate (2.2 L, 8.0 V), EMD-14B (145.5 g, 0.22 mol, 1.0 eq), N,N-diisopropylethylamine (139.6 g, 1.08 mol, 5.0 eq) at 20˜25° C. After cooling to 10˜20° C., propylphosphonic anhydride (346.4 g, 0.54 mol, 2.5 eq) was added dropwise with stiring at below 25° C. Then, the mixture was stirred at 20˜25° C. for at least 2.5 h and monitored by HPLC until EMD-12B less than or equal to 0.5%. The solution was diluted with heptane (2.2 L) at 0˜10° C. and quenched slowly with HCl (aq, 1.0 N, 2.2 L). The organic phase was washed HCl (aq, 1.0N, 2.2 L), NaHCO.sub.3 (sat, 2.2 L×2), concentrated at below 40° C. until no distillate drops out, and exchanged with heptane/MTBE (0.44 L, 1.5:1, v/v) at below 40° C. The residue was dissolved in heptane/MTBE (1.65 L, 1.5:1, v/v) and seed crystal (0.1%, w/w) was added at 20˜25° C. The mixture was stirred for at least 16 h at 20˜25° C. and filtered. The filter cake was washed with heptane (0.66 L), dried under vacuum at 40˜45° C. This resulted in 242.4 g (83.4%) of (R)-1-(benzyloxy)-1-oxopropan-2-yl N-methyl-N-((6S,9R,12S,15R,18S,21R)-6,12,18-triiso-butyl-2,2,5,11,15,17-hexamethyl-9,21-bis(4-morpholinobenzyl)-4,7,10,13,16,19-hexaoxo-3,8,14,20-tetraoxa-5,11,17-triazadocosan-22-oyl)-L-leucinate (EMD-16B) as a white solid: MS (ES, m/z): 1328 (M+H);

##STR00049##

[0146] (R)-1-(benzyloxy)-1-oxopropan-2-yl N-((2R,5S,8R,11S,14R,17S)-5,11-diisobutyl-6,8,12,19-tetramethyl-17-(methylamino)-2,14-bis(4-morpholinobenzyl)-4,7,10,13,16-pentaoxo-3,9,15-trioxa-6,12-diazaicosanoyl)-N-methyl-L-leucinate (EMD-20B): Into a 5 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-16B (376.4 g, 0.28 mol, 1.0 eq) in HC/EA (1128 mL, 3.0 V) below 25° C. The mixture was stirred for at least 1 h at 20˜25° C. and monitored by HPLC until EMD-16B was less than or equal to 0.5%. The resulting solution was concentrated at below 40° C. until no distillate drops out and exchanged with ethyl acetate (376.4 mL×2) at below 40° C. The residue was dissolved in ethyl acetate (1128 mL) and N,N-diisopropylethylamine (376.4 g) was added at 20˜25° C. The mixture was washed with NaHCO3 (sat, 1128 mL×2). The organic was concentrated at below 40° C. until no distillate drops out. This resulted in 313.56 g (90.1%) of (R)-1-(benzyloxy)-1-oxopropan-2-yl N-((2R,5S,8R,11S,14R,17S)-5,11-diisobutyl-6,8,12,19-tetramethyl-17-(methylamino)-2,14-bis(4-morpholinobenzyl)-4,7,10,13,16-pentaoxo-3,9,15-trioxa-6,12-diazaicosanoyl)-N-methyl-L-leucinate (EMD-20B) as a yellow oil; MS (ES, m/z): 1228 (M+H);

##STR00050##

[0147] (3S,6R,9S,12R,15S,18R,21S,24R)-3,9,15,21-tetraisobutyl-8,12,14,20,24-pentamethyl-6,18-bis(4-morpholinobenzyl)-4,7,10,13,16,19,22-heptaoxo-5,11,17,23-tetraoxa-2,8,14,20-tetraazapentacosan-25-oic acid (EMD-18B): Into a 10 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-20B (313.56 g, 0.26 mol, 1.0 eq) in EtOH (3.2 L, 10.0V) at 20˜25° C., The reactor was evacuated and flushed with nitrogen for three times and Pd/C (21.95 g, 7% w/w) was added. Then the reactor was evacuated and flushed with nitrogen for three times again, and kept hydrogen bubbling underneath the reaction mixture surface. The mixture was stirring for at least for 4 h at 20-25° C. and monitored by HPLC until EMD-20B was less than or equal to 1.0%. After the reaction completing, the hydrogen bubbling was cut off. The mixture was filtered through celite (2.0 kg) and filter cake was rinsed with ethyl acetate (0.64 L×3), and the filtrate was concentrated at below 40° C. until no distillate drops out. The residue was slurred with ethyl acetate (0.7 L) for at least 3 h and filtered; the filter cake was rinsed with ethyl acetate (0.32 L×2). The solid was dried under vacuum at 40˜45° C. This resulted in 234.2 g (80.6%) of (3S,6R,9S,12R,15S,18R,21S,24R)-3,9,15,21-tetraisobutyl-8,12,14,20,24-pentamethyl-6,18-bis(4-morpholinobenzyl)-4,7,10,13,16,19,22-heptaoxo-5,11,17,23-tetraoxa-2,8,14,20-tetraazapentacosan-25-oic acid (EMD-18B) as an off white solid; MS (ES, m/z): 1138 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.34-7.16 (m, 8H), 5.68-5.28 (m, 3H), 5.11-5.04 (m, 3H), 4.93-4.86 (m, 1H), 4.03-3.99 (m, 1H), 3.85-3.82 (m, 8H), 3.23-3.22 (m, 8H), 3.23-2.76 (m, 13H), 2.49 (s, 2H), 2.07 (s, 2H), 1.66-1.45 (m, 8H), 1.43-1.16 (m, 10H), 0.99-0.64 (m, 24H).

##STR00051##

[0148] (3S,6R,9S,12R,15S,18R,21S,24R)-3,9,15,21-tetraisobutyl-4,6,10,16,18,22-hexamethyl-12,24-bis(4-morpholinobenzyl)-1,7,13,19-tetraoxa-4,10,16,22-tetraazacyclotetracosan-2,5,8,11,14,17,20,23-octaone (Emodepside): Into a 10 L reactor purged and maintained with an inert atmosphere of nitrogen, was placed a solution of EMD-18B (234.2 g, 0.21 mol, 1.0 eq) in ethyl acetate (3.8 L, 16.0 V), N,N-diisopropylethylamine (131.84 g, 1.02 mol, 5.0 eq) at 20˜25° C. After cooling to 10˜20° C., propylphosphonic anhydride (324.5 g, 0.51 mol, 2.5 eq) was added dropwise with stiring at below 25° C. Then, the mixture was stirred at 20˜25° C. for at least 2.5 h and monitored by HPLC until EMD-18B less than or equal to 0.5%. The mixture was diluted with heptane (2.38 L) at 0˜10° C. and quenched slowly with HCl (aq, 1.0 N, 2.38 L). The organic phase was washed HCl (aq, 1.0N, 2.38 L), NaHCO.sub.3 (sat, 2.38 L×2), concentrated at below 40° C. until no distillate drops out, and exchanged with EtOH (0.48 L×2) at below 40° C. The residue was dissolved in EtOH (0.72 L) at 45˜55° C. and seed crystal (0.1%, w/w) was added at 20˜25° C. The mixture was stirred for at least 16 h at 20˜25° C. and filtered. The filter cake was rinse with EtOH (0.24 L). The solid was dried under vacuum at 40±5° C. The crude product was recrystallized with ethyl acetate. This resulted in 118.24 g (51.3%) of (3S,6R,9S,12R,15S,18R,21S,24R)-3,9,15,21-tetraisobutyl-4,6,10,16,18,22-hexamethyl-12,24-bis(4-morpholinobenzyl)-1,7,13,19-tetraoxa-4,10,16,22-tetraazacyclotetracosan 2,5,8,11,14,17,20,23-octaone (Emodepside) as a white solid; MS (ES, m/z): 1120 (M+H); .sup.1H NMR (DMSO-d.sub.6, 300 MHz) 7.16 (d, J=8.71 Hz, 4H), 6.87 (d, J=8.2 Hz, 4H), 5.68 (q, J=8.0 Hz, 1H), 5.51-4.04 (m, 7H), 3.74-3.71 (m, 8H), 3.08-3.04 (m, 8H), 2.99-2.96 (m, 4H), 2.90-2.88 (m, 4H), 2.83-2.82 (m, 4H), 2.78 (s, 2H), 2.70 (s, 2H), 1.78-1.38 (m, 8H), 1.31-1.14 (m, 6H), 0.97-0.69 (m, 28H).

3. Preparation of PF1022A (Method 1; Cf. Reaction Scheme in FIG. 3 and NMR Spectra in FIG. 4)

[0149] 3-1. Synthetic Procedure

##STR00052##

[0150] To a stirred solution of HO-TAGa (1.69 g, 1.85 mmol) in CH.sub.2C12 (37 mL) was added 0.2 M toluene solution of unit 1 (12.0 mL, 2.40 mmol), 4-dimethylaminopyridine (12 mg, 93.0 μmol), and N,N′-dicyclohexylcarbodiimide (1.30 g, 2.78 mmol) at room temperature under N.sub.2 atmosphere. After stirring for 2 h, the reaction mixture was then cooled to −5° C., and MeOH (185 mL) was added. The resulting heterogeneous solution was stirred for further 15 min at −5° C., and the colorless precipitate was filtered and washed with additional MeOH (500 mL) to afford N-Fmoc-N-MeLeu-D-Lac-O-TAGa (2.46 g, 100%) as a colorless powder.

[0151] mp: 44-45° C.

[0152] [α].sub.D.sup.24: −10.2 (c 1.0, CHCl.sub.3)

[0153] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.78-7.74 (complex m, 2H), 7.60-7.56 (complex m, 2H), 7.39 (m, 2H), 7.29 (m, 2H), 6.50 (s, 4/3H), 6.48 (s, 2/3H), 5.12-5.00 (complex-m, 4H), 4.67 (dd, J=6.3, 9.7 Hz, 3/10H), 4.58 (dd, J=6.3 Hz, 10.9 Hz, 4/10H), 4.50 (dd, J=6.9 Hz, 10.3 Hz, 6/10H), 4.38-4.34 (complex m, 9/10H), 4.30 (m, 5/10H), 4.23 (t, J=6.3 Hz, 3/10H), 3.93 (m, 6H), 2.86 (s, 2H), 2.83 (s 1H), 1.76 (m, 6H), 1.64-1.42 (complex m, 9H), 1.31-1.14 (complex m, 87H), 0.96-0.87 (complex m, 14H), 0.78 (d, J=6.9 Hz, 1H).

[0154] HRMS (FAB, NBA matrix) m/z: 1334.0748 (M.sup.+, calcd for C.sub.86H.sub.143NO.sub.9: 1334.0763)

##STR00053##

[0155] Following the procedure described for general procedure of Fmoc deprotection, N-Fmoc-N-MeLeu-D-Lac-O-TAGa (1.00 g, 0.749 mmol) was converted to 1 (816 mg, 98%) as a colorless powder.

[0156] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 6.50 (s, 2H), 5.16 (q, J=6.9 Hz, 1H), 5.08 (d, J=12.0 Hz, 1H), 5.04 (d, J=12.0 Hz, 1H), 3.93 (m, 6H), 3.30 (t, J=7.5 Hz, 1H), 2.37 (s, 3H), 1.75 (m, 6H), 1.53-1.42 (complex m, 10H), 1.32-1.25 (complex m, 86H), 0.93-0.86 (complex m, 15H).

[0157] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 170.6, 153.3, 138.4, 130.2, 106.4, 73.5, 69.2, 68.9, 67.6, 61.4, 42.2, 34.5, 32.0, 30.4, 29.8 (×2), 29.5 (×2), 26.2, 25.0, 22.8, 22.6, 22.5, 17.1, 14.2.

[0158] HRMS (FAB, NBA matrix) m/z: 1113.0151 [(M+H)+, calcd for C.sub.71H.sub.34NO.sub.7: 1113.0160]

##STR00054##

[0159] To a stirred solution of 1 (800 mg, 0.719 mmol) in CH.sub.2C12 (25 mL) was added unit 2 (426 mg, 0.827 mmol), N,N-diisopropylethylamine (0.429 mL, 2.52 mmol), and PyBroP (496 mg, 1.222 mmol) at room temperature. After stirring for 88 h, the reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford 2 (1.11 g, 96%) as a colorless powder.

[0160] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.76-7.72 (complex m, 2H), 7.62-7.40 (complex m, 2H), 7.39-7.17 (complex m, 9H), 6.47 (m, 2H), 5.47-5.27 (complex m, 2H), 5.15-4.97 (complex m, 4H), 4.69-4.13 (complex m, 3H), 3.92 (complex m, 6H), 3.07 (m, 2H), 2.85 (complex, 6H), 1.80-1.25 (complex m, 105H), 1.02-0.72 (complex m, 21H).

[0161] HRMS (FAB, NBA matrix) m/z: 1632.2163 [(M+Na).sup.+, calcd for C.sub.102H.sub.164N.sub.2O.sub.12Na: 1632.2182]

##STR00055##

[0162] Following the procedure described for general procedure of TAGa cleavage, 2 (614 mg, 0.381 mmol) was converted to 3 (261 mg, 95%) as an yellow oil, which was used next reaction without further purification.

##STR00056##

[0163] Following the procedure described for general procedure of Fmoc deprotection, 2 (472 mg, 0.293 mmol) was converted to 4 (404 mg, 100%) as a colorless powder.

[0164] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.27 (m, 5H), 6.49 (s, 2H), 5.50 (dd, J=5.7, 8.6 Hz, 1H), 5.32 (dd, J=4.6, 10.9 Hz, 1H), 5.09-5.00 (complex m, 3H), 3.93 (m, 6H), 3.28 (t, J=6.9 Hz, 1H), 3.09 (m, 2H), 2.92 (s, 3H), 2.27 (s, 3H), 1.82-1.25 (complex m, 105H), 0.89-0.77 (complex m, 21H).

[0165] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 175.6, 175.1, 175.0, 174.8, 170.9, 170.5 (×2), 170.4, 169.8, 169.7, 166.7, 165.1, 153.3, 138.5, 138.3, 135.8 (×2), 130.2, 129.5, 129.3, 128.7, 128.6, 128.5 (×2), 127.2, 107.0, 106.9, 105.4, 78.1, 73.5, 71.9, 71.6, 69.4, 69.2, 68.9, 67.7, 67.5, 66.9, 65.6, 61.3, 61.2, 59.7, 57.7, 54.7, 42.3, 42.2, 42.1, 40.0, 38.8, 37.5, 36.9, 34.4, 34.3, 32.8, 32.0, 31.3, 30.4, 29.8 (×2), 29.6, 29.5 (×2), 26.2, 25.0, 24.8, 24.7, 24.6, 23.4, 22.9, 22.8, 22.5 (×2), 22.4 (×2), 21.9, 21.4, 20.5, 17.0, 16.9, 16.8, 14.2.

[0166] HRMS (FAB, NBA matrix) m/z: 1388.1664 [(M+H).sup.+, calcd for C.sub.87H.sub.155N.sub.2O.sub.10: 1388.1682]

##STR00057##

[0167] To a stirred solution of 2 (330 mg, 0.238 mmol) in CH.sub.2Cl.sub.2 (4.8 mL) was added 3 (221 mg, 0.309 mmol), N,N-diisopropylethylamine (0.150 mL, 0.881 mmol), and PyBroP (197 mg, 0.428 mmol) at room temperature. After stirring for 42 h, the reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford 5 (477 mg, 96%) as a colorless powder.

[0168] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.74 (m, 2H), 7.53 (m, 2H), 7.38 (m, 2H), 7.32-7.15 (complex m, 12H), 6.48 (m, 2H), 5.51-4.96 (complex m, 10H), 4.70-4.12 (complex m, 3H), 3.93 (m, 6H), 3.23 (dd, J=6.9, 13.7 Hz, 1H), 3.08-2.70 (complex m, 15H), 1.80-1.25 (complex m, 114H), 0.95-0.78 (complex m, 33H).

[0169] HRMS (FAB, NBA matrix) m/z: 2106.4949 [(M+Na).sup.+, calcd for C.sub.128H.sub.202N.sub.4O.sub.18Na.sub.1: 2106.4912]

##STR00058##

[0170] Following the procedure described for general procedure of Fmoc deprotection, 5 (450 mg, 0.206 mmol) was converted to the corresponding amine (398 mg, 98%) as a colorless powder.

[0171] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.25 (m, 10H), 6.48 (s, 2H), 5.57-4.99 (complex m, 9H), 3.93 (m, 6H), 3.26-2.78 (complex m, 14H), 2.24 (s, 3H), 1.80-1.25 (complex m, 114H), 0.90-0.78 (complex m, 33H).

[0172] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 175.6, 175.2 (×2), 171.5, 171.1, 170.8 (×2), 170.6, 170.5 (×2), 170.3, 153.3, 138.5 (×2), 138.3, 136.1, 135.9, 135.5, 130.2, 130.1, 130.0, 129.8, 129.7, 129.6, 129.4 (×2), 128.8, 128.7, 128.6, 128.5, 127.4 (×2), 127.2, 127.1, 126.9, 126.8, 107.0 (×2), 106.9, 73.5, 72.5, 72.2, 71.7, 71.6, 69.8, 69.4, 69.2, 68.1, 68.0, 67.8, 67.5 (×2), 66.9, 61.4, 57.4, 55.2, 54.8, 54.6 (×2), 38.8, 37.7, 37.6, 37.4 (×2), 37.1 (×2), 37.0, 36.9, 34.7, 34.6, 32.2, 32.0, 31.9, 31.7, 31.6, 31.4, 31.3, 31.2, 30.4, 29.8 (×2), 29.6, 29.5 (×2), 26.2, 24.9, 24.8 (×2), 24.7, 24.6, 24.5, 23.5, 23.4, 23.3, 23.1 (×2), 23.0, 22.8, 22.7, 22.5, 22.4, 22.3, 22.0, 21.5, 21.4, 21.3 (×2), 20.5, 16.9, 16.8, 16.6, 14.2.

[0173] HRMS (FAB, NBA matrix) m/z: 1862.4425 [(M+H).sup.+, calcd for C.sub.113H.sub.193N.sub.4O.sub.16: 1862.4412]

##STR00059##

[0174] Following the procedure described for general procedure of TAGa cleavage, N-MeLeu-D-PhLac-N-MeLeu-D-Lac-N-MeLeu-D-PhLac-N-MeLeu-D-LacO-TAGa (380 mg, 0.204 mmol) was converted to the corresponding carboxylic acid (198 mg, 98%) as a yellow oil, which was used next reaction without further purification.

##STR00060##

[0175] Reaction for 0.005M Concentration of Substrate

[0176] A crude of previous reaction (90 mg, 0.0895 mmol) was dissolved in CH.sub.2Cl.sub.2 (18 mL, 0.005 M). The reaction mixture was added N,N-diisopropylethylamine (76 μL, 4.48 mmol) and PyBOP (93 mg, 0.179 mmol) at room temperature. After being stirred for 48 h, the reaction mixture was quenched with saturated aqueous NaHCO.sub.3 (18 mL) at 0° C. and this mixture was extracted with CHCl.sub.3 (20 mL×2). The combined organic layers were washed with 10% aqueous NaHSO.sub.4 (60 mL) and brine (60 mL), dried over Na.sub.2SO.sub.4, filtered and concentrated in vacuo. The crude was purified by column chromatography on silica gel (CHCl3: MeOH=400:1 to 40:1) to provide PF1022A (55 mg, 65%) as a colorless solid.

[0177] Reaction for 0.05M Concentration of Substrate

[0178] According to the procedure for cyclization mentioned above, a crude of previous reaction (90 mg, 0.0895 mmol) was cyclized in CH.sub.2Cl.sub.2 (1.8 ml, 0.05 M) with N,N-diisopropylethylamine (76 μL, 4.48 mmol) and PyBOP (93 mg, 0.179 mmol) at room temperature for 48 h to provide PF1022A (40 mg, 49%) as a colorless solid.

[0179] mp: 100-103° C.

[0180] [α].sup.22.sub.D: −99.4° C. (c 0.06, MeOH)

[0181] IR (KBr) {tilde over (ν)}: 1743, 1666, 1466, 1412, 1265, 1188, 1126, 1080, 1026, 748, 701

[0182] .sup.1H-NMR (500 MHz, CD.sub.3OD) δ: 7.29 (m, 10H), 5.82 (t, J=7.5 Hz, 1H), 5.72 (m, 2H, rotamer), 5.54 (q, J=6.9 Hz, 1H), 5.44 (dd, J=4.6, 11.7 Hz, 1H), 5.40 (dd, J=4.6, 11.7 Hz, 1H, rotamer), 5.23 (dd, J=4.6, 11.7 Hz, 1H), 5.18 (q, J=6.9 Hz, 1H, rotamer), 4.77 (dd, J=3.4, 11.2 Hz, 1H), 3.14 (m, 4H), 3.00 (s, 5/2H, rotamer), 2.91 (m, 7H, rotamer), 2.82 (s, 5/2H, rotamer), 1.84 (m, 1H), 1.77-1.47 (complex m, 11H), 1.39 (d, J=6.3 Hz, 3H), 1.05 (d, J=6.3 Hz, 3H), 0.98 (d, J=6.9 Hz, 3H), 0.80 (d, J=6.3 Hz, 3H), 0.95-0.82 (complex m, 18H).

[0183] .sup.13C-NMR (125 MHz, CD.sub.3OD) δ: 174.4, 173.5, 173.1, 173.1, 172.3, 172.0, 171.0, 170.7, 136.4, 136.2, 130.8, 130.7, 130.7, 129.8, 129.7, 129.7, 128.4, 128.3, 72.5, 72.3, 69.9, 68.5, 58.6, 55.7, 55.5, 55.4, 39.0, 38.9, 38.6, 38.6, 37.8, 37.3, 32.0, 31.3, 31.1, 30.0, 26.2, 26.1, 25.5, 25.2, 23.9, 23.7, 23.7, 23.6, 21.7, 21.6, 21.4, 21.1, 17.5, 17.2.

[0184] HRMS (FAB, NBA matrix) m/z: 971.5353 [(M+Na).sup.+, calcd for C.sub.52H.sub.76N.sub.4O.sub.12Na.sub.1: 971.5357] [0185] *Literature (J. Antibiot., 1992, 45, 692-697)

[0186] mp: 104-106° C.

[0187] [α].sup.22.sub.D: −102° C. (c 0.1, MeOH)

[0188] .sup.1H-NMR (400 MHz, CD.sub.3OD) δ: 7.30-7.20 (PhH, 10H), 5.80 and 5.75 (C.sub.αH-PhLac, 1H×2), 5.54 and 5.16 (C.sub.αH-Lac, 1H×2), 5.43, 5.42, 5.22 and 4.78 (C.sub.αH-Leu, 1H×4), 3.22-3.15 (C.sub.βH.sub.2-PhLac, 2H×2), 3.00, 2.90, 2.88 and 2.80 (N-Me-Leu, 3H×4), 1.87-1.50 (C.sub.βH.sub.2-Leu, 2H×4), 1.40 (C.sub.γH-Leu, 1H×4), 1.38 (C.sub.βH.sub.3-Lac, 3H), 1.02-0.75 (C.sub.δH.sub.3-Leu, 6H×4), 0.88 (C.sub.βH.sub.3-Lac, 3H).

[0189] .sup.13C-NMR (100 MHz, CD.sub.3OD) δ: 174.4, 173.4, 172.4, 172.4, 172.1, 172.1, 171.0, 170.8, 136.5, 136.2, 130.7, 130.7, 130.7, 130.7, 129.7, 129.7, 129.7, 129.7, 128.3, 128.2, 72.5, 72.3, 69.9, 68.4, 58.6, 55.7, 55.5, 55.4, 39.0, 38.9, 38.6, 38.6, 37.9, 37.4, 32.0, 31.3, 31.1, 29.9, 26.2, 26.1, 25.6, 25.2, 23.6, 23.6, 23.5, 23.5, 21.7, 21.6, 21.4, 21.0, 17.5, 17.2.

[0190] 4. Preparation of PF1022A (Method 2: Cf. Reaction Scheme in FIG. 5)

[0191] 4-1. Synthetic Procedure

##STR00061##

[0192] To a stirred solution of HO-TAGa (170 mg, 0.186 mmol) in CH.sub.2C2 (3.7 mL) was added 0.1 M toluene solution of unit 2 (2.42 mL, 0.242 mmol), 4-dimethylaminopyridine (1.1 mg, 9.30 μmol), and N,N′-dicyclohexylcarbodiimide (58 mg, 0.279 mmol) at room temperature under N.sub.2 atmosphere. After stirring for 1 h, the reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford N-Fmoc-N-MeLeu-D-PhLac-O-TAGa (266 mg, 100%) as a colorless powder.

[0193] mp: 44-45° C.

[0194] [α].sub.D.sup.27: −6.1 (c 1.74, CHCl.sub.3)

[0195] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.76 (complex m, 2H), 7.54 (m, 2H), 7.39 (m, 2H), 7.30 (m, 1H), 7.26-7.14 (complex m, 4H), 7.08 (m, 2H) 6.44 (m, 2H), 5.20 (m, 1H), 5.04-4.94 (complex m, 3H), 4.61-4.15 (complex m, 3H), 3.92 (m, 6H), 3.10 (m, 2H), 2.72 (s, 3H), 1.76 (m, 6H), 1.60-1.25 (complex m, 93H), 0.90-0.71 (complex m, 15H).

[0196] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 177.2, 175.2, 169.5, 153.3, 138.4, 135.9, 130.0, 129.6, 129.3, 128.6, 128.4, 127.1, 107.5, 107.2, 73.5, 73.1, 69.2, 67.8, 61.6, 42.5, 37.4, 34.5, 32.0, 30.4, 29.8 (×2), 29.6, 29.5, 26.2, 24.8, 22.8, 22.6, 22.5, 14.2.

[0197] HRMS (FAB, NBA matrix) m/z: 1410.1063 [(M+H).sup.+, calcd for C.sub.92H.sub.147NO.sub.9: 1410.1076]

##STR00062##

[0198] Following the procedure described for general procedure of Fmoc deprotection, N-Fmoc-N-MeLeu-D-PhLac-O-TAGa (457 mg, 0.324 mmol) was converted to 6 (378 mg, 99%) as a colorless powder.

[0199] mp: 48-49° C.

[0200] [α].sub.D.sup.26: +4.2 (c1.10, CHCl.sub.3)

[0201] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.22 (m, 5H), 6.48 (s, 2H), 5.28 (dd, J=4.0, 10.3 Hz, 1H), 5.08 (d, J=12.0 Hz, 1H), 5.04 (d, J=12.0 Hz, 1H), 3.93 (m, 6H), 3.24 (dd, J=4.0 Hz, 14.3 Hz, 1H), 3.17 (t, J=6.9 Hz, 1H), 3.07 (dd, J=9.7, 14.3 Hz, 1H), 2.18 (s, 3H), 1.76 (m, 6H), 1.48-1.25 (complex m, 93H), 0.90-0.76 (complex m, 15H).

[0202] HRMS (FAB, NBA matrix) m/z: 1189.0458 [(M+H).sup.+, calcd for C.sub.77H.sub.138NO.sub.7: 1189.0473]

##STR00063##

[0203] To a stirred solution of 6 (358 mg, 0.301 mmol) in CH.sub.2Cl.sub.2 (6.0 ml) was added 0.1 M toluene solution of unit 1 (3.31 mL, 0.331 mmol), N.N-diisopropylethylamine (0.15 mL, 0.903 mmol), and PyBroP (211 mg, 0.452 mm) at room temperature. After stirring for 13 h, reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford 7 (468 mg, 97%) as a colorless powder.

[0204] mp: 47-48° C.

[0205] [α].sub.D26: −13.9 (c 1.10, CHCl.sub.3)

[0206] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ:7.75 (m, 2H), 7.59 (m, 2H), 7.39 (m, 2H), 7.30-7.09 (complex m, 7H), 6.44 (m, 2H), 5.36-4.96 (complex m, 6H), 4.71-4.24 (complex m, 3H), 3.93 (t, J=6.5 Hz, 6H), 3.14 (m, 2H), 2.90-2.81 (complex s, 6H), 1.80-1.25 (complex m, 105H), 0.96-0.76 (complex m, 21H).

[0207] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 171.6, 171.2, 171.1, 170.9, 169.3, 157.0, 153.3, 144.3, 143.9, 141.4 (×2), 138.4, 135.9, 130.0, 129.9, 129.8, 129.7, 129.6, 129.5, 129.3, 128.7, 128.5, 128.4, 127.7, 127.6, 127.0, 125.3, 125.1, 125.0, 124.9, 120.0, 107.5, 107.2, 74.1, 74.0, 73.9, 73.8, 73.5, 71.3, 69.2, 67.9, 67.7, 57.4, 57.2, 56.7, 56.6 (×2), 54.5 (×2), 47.4 (×2), 47.3, 37.6, 37.3, 37.2, 37.1, 37.0, 32.0, 31.1, 30.7, 30.6 (×2), 30.5, 30.4, 30.3, 30.2, 29.8 (×2), 29.6, 29.5 (×2), 26.2, 24.9, 24.8, 24.7, 24.6, 24.4, 23.4, 23.2, 22.9, 22.8, 22.1, 21.4, 21.2, 16.8, 14.2.

[0208] HRMS (FAB, NBA matrix) m/z: 1609.2274 (M.sup.+, calcd for C.sub.102H.sub.168N.sub.2O.sub.12: 1609.2284)

##STR00064##

[0209] Following the procedure described for general procedure of TAGa cleavage, 7 (244 mg, 0.152 mmol) was converted to 8 (106 mg, 97%) as a yellow oil, which was used next reaction without further purification.

##STR00065##

[0210] Following the procedure described for general procedure of Fmoc deprotection, 7 (204 mg, 0.127 mmol) was converted to 9 (176 mg, 100%) as a colorless powder.

[0211] mp: 47-48° C.

[0212] [α].sub.D.sup.26: −2.1 (c 1.1, CHCl.sub.3)

[0213] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.19 (m, 5H), 6.45 (s, 2H), 5.45 (q, J=6.9 Hz, 1H), 5.31 (ddd, J=4.6, 11.2, 19.6 Hz, 1H), 5.22 (dd, J=5.2, 6.9 Hz, 1H), 5.03 (m, 2H), 3.94 (m, 6H), 3.33-2.95 (complex m, 3H), 2.80 (s, 3H), 2.38 (s, 3H), 1.82-1.25 (complex m, 105H), 0.96-0.75 (complex m, 21H).

[0214] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 175.0, 171.1, 171.0, 169.2, 153.3, 130.0, 129.8, 129.7, 129.3, 128.7, 128.6, 128.5, 127.4, 127.1, 126.9, 107.5, 107.2, 73.8, 73.5, 71.3, 69.2, 67.9, 67.7, 67.4, 67.3, 61.2, 57.5, 54.6, 42.3, 42.2, 37.3, 37.2, 37.0, 34.6, 32.0, 31.1, 30.4, 29.8 (×2), 29.6, 29.5 (×2), 26.2, 25.0, 24.8, 23.4, 23.0, 22.8, 22.7, 22.4, 22.1, 21.3, 16.9, 16.8, 14.2.

[0215] HRMS (FAB, NBA matrix) m/z: 1388.1676 [(M+H).sup.+, calcd for C.sub.87H.sub.155N.sub.2O.sub.10: 1388.1682]

##STR00066##

[0216] To a stirred solution of 9(155 mg, 96.2 μmol) in CH.sub.2Cl.sub.2 (1.9 mL) was added 8(103 mg, 0.144 mmol), N,N-diisopropylethylamine (73 μL, 0.434 mmol), and PyBroP (112 mg, 0.241 mmol) at room temperature. After stirring for 66 h, the reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford 10 (201 mg, 100%) as a colorless powder.

[0217] mp: 47-48° C.

[0218] [α].sub.D.sup.27: −27.2 (c 1.1, CHCl.sub.3)

[0219] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.75 (m, 2H), 7.59 (m, 2H), 7.38 (n, 2H), 7.30-7.12 (complex m, 12H), 6.44 (m, 2H), 5.43-4.96 (complex m, 10H), 4.69-4.22 (complex m, 3H), 3.93 (m, 6H), 3.24-2.69 (complex m, 16H), 1.80-1.25 (complex m, 114H), 0.95-0.75 (complex m, 33H).

[0220] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 174.1, 171.5, 171.4, 171.3, 171.2, 171.1 (×2), 170.9, 170.8, 170.7, 170.6, 170.5, 170.4, 170.0, 169.2, 157.0, 156.5, 153.3, 144.3, 144.2, 144.0 (×2), 141.4 (×2), 138.6, 138.4, 136.1, 136.0, 135.9 (×2), 135.7, 135.6, 135.3, 130.0, 129.8, 129.7, 129.6, 129.5, 129.3, 128.8, 128.7, 128.6, 128.4, 127.7, 127.4, 127.1 (×2), 127.0. 125.3, 125.2, 125.1, 125.0, 120.0, 107.5, 107.2, 107.1, 73.9, 73.5, 72.5, 71.3, 69.2, 68.0, 67.7, 57.5, 56.6 (×2), 55.1, 55.0, 54.9, 54.7, 54.4, 47.4, 47.3, 40.9, 40.6, 38.7, 37.6, 37.3, 37.2, 37.1, 32.0, 31.9, 31.7, 31.5, 31.3, 31.2, 31.0, 30.7, 30.6, 30.4, 30.3, 29.8 (×2), 29.6, 29.5 (×2), 25.0, 24.9, 24.8, 24.7, 24.5, 24.4 (×2), 23.4, 23.3, 23.1, 23.0, 22.9, 22.8, 22.3, 22.1, 22.0, 21.3, 21.2, 16.8, 16.6, 16.5, 14.2.

[0221] HRMS (FAB, NBA matrix) m/z: 2106.4910 [(M+Na).sup.+, calcd for C.sub.128H.sub.202N.sub.4O.sub.18Na: 2106.4912]

##STR00067##

[0222] Following the procedure described for general procedure of Fmoc deprotection, 10 (181 mg, 86.8 μmol) was converted to the corresponding amine (163 mg, 100%) as a colorless powder.

[0223] mp: 47-48° C.

[0224] [α].sub.D.sup.27: −18.7 (c 1.3, CHCl.sub.3)

[0225] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.20 (m, 10H), 6.44 (s, 2H), 5.50-4.95 (complex m, 9H), 3.93 (m, 6H), 3.31-2.72 (complex m, 14H), 2.36 (m, 3H), 1.80-1.25 (complex m, 114H), 0.99-0.81 (complex m, 33H).

[0226] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 171.4, 171.2, 171.0, 170.9, 170.6, 170.4, 153.3, 138.3, 136.1, 136.0, 135.9, 135.8, 130.0, 129.8 (×2), 129.7, 129.6 (×3), 129.5, 129.4, 129.2, 129.2 (×2), 128.8, 128.7, 128.6, 128.4, 127.4, 127.3, 127.2 (×2), 127.1, 127.0, 107.5, 107.2, 107.1, 73.9, 73.5, 72.3, 72.2, 71.3, 69.2, 68.0 (×2), 67.7, 67.4, 61.3, 55.2, 55.0, 54.8, 54.5, 54.4, 42.4, 40.6, 38.7, 37.7, 37.2, 37.1, 34.7 (×2), 32.0, 31.7, 31.5, 31.0, 30.4, 29.8 (×2), 29.6, 29.5 (×2), 26.2, 25.0, 24.9 (×2), 24.7, 23.5, 23.4 (×2), 23.3, 23.2, 23.0, 22.8, 22.4, 22.1, 21.9, 21.3 (×2), 16.9, 16.8 (×3), 16.7, 16.6, 16.5, 14.2.

[0227] HRMS (FAB, NBA matrix) m/z: 1862.4462 [(M+H).sup.+, calcd for C.sub.113H.sub.193N.sub.4O.sub.16: 1862.4412]

##STR00068##

[0228] Following the procedure described for general procedure of TAGa cleavage, N-MeLeu-D-Lac-N-MeLeu-D-PhLac-N-MeLeu-D-Lac-N-MeLeu-D-PhLac-O-TAGa (143 mg, 0.768 mmol) was converted to the corresponding carboxylic acid (78 mg, 100%) as a yellow oil, which was used next reaction without further purification.

##STR00069##

[0229] A crude of previous reaction (78 mg, 0.0777 mmol) was dissolved in CH.sub.2C2 (16 mL, 0.005 M). The reaction mixture was added N,N-diisopropylethylamine (66 μL, 0.389 mmol) and PyBOP (81 mg, 0.155 mmol) at room temperature. After stirring for 48 h, the reaction mixture was quenched with saturated aqueous NaHCO.sub.3 (16 mL) at 0° C. and this mixture was extracted with CHCl.sub.3 (20 mL×2). The combined organic layers were washed with 10% aqueous NaHSO.sub.4 (60 mL) and brine (60 mL), dried over Na.sub.2SO.sub.4, filtered and concentrated in vacuo. The crude was purified by column chromatography on silica gel (CHCl.sub.3: MeOH=400:1 to 40:1) to provide PF1022A (48 mg, 65%) as a colorless solid.

[0230] All physical data for synthetic PF1022A matched with the data of authentic PF1022A.

[0231] 5. Preparation of Emodepside (Method 1; Cf. Reaction Schemes in FIG. 6, NMR Spectra in FIG. 7 and LC-UV Spectra in FIG. 8)

[0232] 5-1. Synthetic Procedure

##STR00070##

[0233] To a stirred solution of 1 (259 mg, 0.233 mmol) in CH.sub.2C2 (4.7 mL) was added 0.2 M toluene solution of unit 3 (0.122 mL, 0.244 mmol), N,N-diisopropylethylamine (0.12 mL, 0.698 mmol), and PyBroP (163 mg, 0.349 mmol) at room temperature. After being stirred at 40 h, reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford 11 (395 mg, 100%) as a colorless powder.

[0234] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.74 (m, 2H), 7.57 (m, 2H), 7.42-7.27 (complex m, 4H), 7.05 (m, 2H), 6.70 (d, J=8.6 Hz, 2H), 6.48 (s, 2H), 5.40 (dd, J=6.9, 8.4 Hz, 3/10H, rotamer), 5.35-5.27 (complex m, 17/10H), 5.10-4.97 (complex m, 4H), 4.72-4.12 (complex m, 3H), 3.93 (m, 6H), 3.75 (m, 4H), 3.00-2.79 (complex m, 12H), 1.80-1.60 (complex m, 9H), 1.49-1.42 (complex m, 9H), 1.27 (complex m, 87H), 0.93-0.80 (complex m, 21H).

[0235] HRMS (FAB, NBA matrix) m/z: 1717.2701 [(M+Na).sup.+, calcd for C.sub.106H.sub.17N.sub.3O.sub.13Na: 1717.2710]

##STR00071##

[0236] Following the procedure described for general procedure of TAGa cleavage, 11 (210 mg, 0.124 mmol) was converted to 12 (100 mg, 0.124 mmol) as a brown oil. This crude was used next reaction without further purification.

##STR00072##

[0237] Following the procedure described for general procedure of Fmoc deprotection, 11 (158 mg, 0.0934 mmol) was converted to 13 (138 mg, 100%) as a colorless powder.

[0238] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.15 (m, 2H), 6.83 (d, J=8.6 Hz, 2H), 6.49 (s, 2H), 5.47 (dd, J=6.9, 8.0 Hz, 1H), 5.32 (dd, J=4.9, 11.2 Hz, 1H), 5.09-5.00 (complex m, 3H), 3.94 (m, 6H), 3.85 (m, 4H), 3.27 (t, J=6.9 Hz, 1H), 3.13-2.79 (complex m, 9H), 2.29 (s, 3H), 1.81-1.25 (complex m, 105H), 1.01-0.78 (complex m, 21H).

[0239] HRMS (FAB, NBA matrix) m/z: 1473.2214 [(M+H).sup.+, calcd for C.sub.91H.sub.62N.sub.3O.sub.11: 1473.2209]

##STR00073##

[0240] To a stirred solution of 13 (138 mg, 0.934 mmol) in CH.sub.2C2 (1.9 mL) was added 12 (100 mg, ˜0.124 mmol), N,N-diisopropylethylamine (48 μL, 0.280 mmol), and PyBroP (65 mg, 0.140 mmol) at room temperature. After stirring for 18 h, the reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford 14 (211 mg, 100%) as a colorless powder.

[0241] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.75 (m, 2H), 7.58 (m, 2H), 7.42-7.28 (complex m, 4H), 7.09 (m, 4H), 6.77 (m, 4H), 6.48 (s, 2H), 5.45-5.15 (complex m, 6H), 5.06-4.97 (complex m, 4H), 4.73-4.12 (complex m, 3H), 3.95-3.73 (complex m, 14H), 3.15-2.73 (complex m, 24H), 1.80-1.25 (complex m, 114H), 0.96-0.77 (complex m, 33H).

[0242] HRMS (FAB, NBA matrix) m/z: 2276.5962 [(M+Na).sup.+, calcd for C.sub.136H.sub.216N.sub.6O.sub.20Na: 2276.5967]

##STR00074##

[0243] Following the procedure described for general procedure of Fmoc deprotection, 14 (211 mg, 0.0934 mmol) was converted to the corresponding amine (178 mg, 94%) as a colorless powder.

[0244] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.15 (m, 4H), 6.82 (m, 4H), 6.49 (s, 2H), 5.14 (t, J=7.45 Hz, 1H), 5.44-5.09 (complex m, 5H), 5.07-5.00 (complex m, 3H), 3.93 (m, 6H), 3.85 (m, 8H), 3.32 (m, 1H), 3.17-2.74 (complex m, 21H), 2.33 (s, 3H), 1.81-1.64 (complex m, 12H), 1.55-1.25 (complex m, 102H), 1.03-0.77 (complex m, 33H).

[0245] HR-MS (FAB, NBA matrix+NaI) m/z: 2032.5488 [(M+H), calcd for C.sub.121H.sub.207N.sub.6O.sub.18: 2032.5467]

##STR00075##

[0246] Following the procedure described for general procedure of TAGa cleavage, N-MeLeu-D-morphPhLac-N-MeLeu-D-Lac-N-MeLeu-D-morphPhLac-N-MeLeu-D-LacO-TAGa (178 mg, 0.0876 mmol) was converted to the corresponding carboxylic acid (0.0876 mmol) as a crude oil, which was used next reaction without further purification.

[0247] Emodepside (Highly Diluted Condition Using PyBOP)

##STR00076##

[0248] To a crude of carboxylic acid (0.0876 mmol) in CH.sub.2Cl.sub.2 (18 mL, 0.005 M) was added N,N-diisopropylethylamine (0.10 mL, 0.613 mmol) and PyBOP (91 mg, 0.175 mmol) at room temperature. After stirring for 19 h, the reaction mixture was quenched with saturated aqueous NaHCO.sub.3 (18 mL) at 0° C. and this mixture was extracted with CHCl.sub.3 (20 mL×3). The combined organic layers were washed with 10% aqueous NaHSO.sub.4 (60 mL) and brine (60 mL), dried over Na.sub.2SO.sub.4, filtered and concentrated in vacuo. The crude was purified by column chromatography on silica gel (CHCl.sub.3: MeOH=400:1 to 100:1) to provide Emodepside (45 mg, 46% for 2 steps) as a light yellow solid.

[0249] mp: 98-103° C.

[0250] [α].sub.D.sup.24: −40.3 (c 0.67, CHCl.sub.3)

[0251] IR (neat) {tilde over (ν)}.sub.max: 2954, 2862, 1743, 1659, 1520, 1458, 1412, 1265, 1234, 1188, 1119, 1072, 1026, 926, 810.

[0252] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.14-7.11 (complex m, 4H), 6.83-6.79 (complex m), 5.64-5.54 (complex m), 5.52-5.43, 5.43-5.39, 5.33, 5.18, 5.06 and 4.46 (5 m, 6H), 3.85 (apparently t, 8H), 3.15-3.04 (complex m, 8H), 3.04-2.92 (complex m, 4H), 3.00, 2.82, 2.79, 2.72 and 2.71 (5 s, 12H), 1.82-1.24 (complex m, 18H), 1.03-0.79 (complex m, 30H).

[0253] .sup.13C-NMR (125 MHz, CDCl.sub.3) δ: 171.6, 171.2, 171.0, 170.9, 170.3, 170.2, 170.1, 169.8, 169.7, 150.2, 130.4, 130.2, 115.7, 115.6, 71.2, 70.8, 68.5, 66.8, 66.7, 57.1, 54.0, 53.9, 49.3, 49.2, 38.0, 37.5, 37.1, 36.9, 36.8, 36.7, 36.6, 36.1, 31.1, 30.6, 30.4, 29.7, 29.6, 29.3, 25.0, 24.8, 24.6, 24.5, 24.5, 24.1, 23.6, 23.5, 23.4, 23.3, 23.3, 23.1, 22.6, 21.6, 21.5, 21.1, 21.1, 21.0, 20.8, 17.1, 15.7.

[0254] HRMS (ESI) m/z: 1141.6404 [(M+Na).sup.+, calcd for C.sub.60H.sub.90N.sub.6O.sub.14Na: 1141.6413] [0255] *Literature (Eur J. Org. Chem., 2012, 1546-1553)

[0256] .sup.1H-NMR (400 MHz, CDCl.sub.3) δ: 7.17-7.09 (m, 4H, Ar—H), 6.86-6.77 (m, 4H, Ar—H), 5.67-5.54 (m, 2H, CαH-Lac), 5.53-5.38, 5.34, 5.19, 5.08 and 4.47 (5 m, 6H, CαH-Leu, CαH-morphPhLac), 3.88-3.81 (pseudo-t, 8H, OCH.sub.2 morpholine), 3.15-3.08 (m, 8H, N—CH.sub.2-morpholine), 3.07-2.85 (m, 4H, CβH.sub.2-morphPhLac), 3.00, 2.83, 2.80, 2.74 and 2.73 (5 s, 12H, NCH.sub.3), 1.83-1.20 (m, 18H, CβH.sub.2-Leu, C7H-Leu, CH.sub.3-Lac), 1.05-0.77 (m, 30H, C6H.sub.3-Leu, CβH.sub.3-Lac).

[0257] .sup.13C-NMR (100 MHz, CDCl.sub.3) δ: 171.7, 171.2, 171.0, 170.6, 170.4, 170.2, 169.8, 141.7, 130.6, 130.4, 116.9, 116.1, 71.3, 70.8, 68.6, 66.9, 66.6, 66.5, 57.1, 54.0, 49.9, 38.1, 37.5, 37.2, 36.7, 36.2, 31.2, 30.5, 29.4, 24.9, 24.7, 24.2, 23.6, 23.5, 23.5, 23.4, 21.2, 21.1, 20.9, 17.1, 15.8.

[0258] Emodepside (Slow Addition Condition Using T3P)

##STR00077##

[0259] Cleavage of TAGa: To a stirring solution of linear compound on TAG (179.0 mg, 0.088 mmol) in DCM (1.8 mL) was added TFA (1.8 mL) at room temperature. After stirring for 6 h at room temperature, the solution was concentrated in vacuo. The resulting mixture was dissolved into toluene (10 mL) and concentrated under reducing pressure for 3 times to remove excess TFA. The crude residue was dissolved into CH.sub.2C2 (1.0 mL), then recrystallized for the cleaved TAGa materials by the addition of MeOH (8.0 mL) at room temperature. The precipitates were filtered off through Celite® pad and washed with MeOH (20 mL). The combined filtrates were concentrated in vacuo. To the resulting product was added 4 M HC/Dioxane (0.05 M for product), followed by diluted with toluene (10 mL) and concentrated to afford the TFA salt free product. To remove excess HCl from a crude product, the product was dissolved again into toluene (10 mL) and concentrated under reducing pressure for 2 times.

[0260] Cyclization: To a stirring solution of T3P® (50% in EtOAc, 110 μL, 0.187 mmol) in DIPEA (110 μL, 0.187 mmol) was added dropwise a crude linear compound (0.088 mmol) in DCM (1.8 mL, 0.05 M including wash) over 2.5 h at room temperature. After stirring for 20 h at room temperature, the reaction mixture was quenched with sat. NaHCO.sub.3 aq. (3.0 mL), extracted with CHCl.sub.3 (2.0 mL×3). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. The crude residue was purified by silica gel column chromatography on silica gel (CHCl.sub.3/MeOH=100/1) to provide Emodepside (86.4 mg, 88%) as an amorphous. The analytical data was identified by the authentic sample.

[0261] 6. Preparation of Emodepside (Method 2: Cf. Reaction Scheme in FIG. 9)

##STR00078##

[0262] To a stirred solution of HO-TAGa (381 mg, 0.417 mmol) in CH.sub.2Cl.sub.2 (8.4 mL) was added 0.2 M toluene solution of unit 3 (2.71 mL, 0.542 mmol), 4-dimethylaminopyridine (2.5 mg, 20.8 mol), and N,N′-dicyclohexylcarbodiimide (129 mg, 0.626 mmol) at room temperature under N.sub.2 atmosphere. After stirring for 1 h, the reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford N-Fmoc-N-MeLeu-D-morphPhLac-O-TAGa (628 mg, 100%) as a colorless powder.

[0263] mp: 46-47° C.

[0264] [α].sub.D.sup.27=−3.1 (c 1.0, CHCl.sub.3)

[0265] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.78 (d, J=7.5 Hz, 1H), 7.74 (d, J=7.5 Hz, 1H), 7.57 (m, 2H), 7.39 (m, 2H), 7.27 (m, 2H), 6.98 (d, J=8.6 Hz, 1H), 6.96 (d, J=8.6 Hz, 1H), 6.67 (m, 2H), 6.49 (2 s, rotamer 4:3, 2H), 5.17 (2 dd, rotamer, J=4.0 Hz, 8.0 Hz, 1H), 5.08-4.98 (complex m, 3H), 4.67-4.13 (complex m, 3H), 3.93 (m, 6H), 3.73 (m, 4H), 3.08 (dd, J=4.0 Hz, 14.6 Hz, 1H), 3.07-2.95 (complex m, 5H), 2.80 (rotamer 4:3, 3H), 1.76 (m, 6H), 1.64-1.53 (complex m, 3H), 1.45 (m, 6H), 1.28 (complex m, 84H), 0.93-0.86 (complex m, 14H), 0.76 (d, J=6.3 Hz, 1H).

[0266] HRMS (FAB, NBA matrix) m/z: 1495.1583 (M.sup.+, calcd for C.sub.96H.sub.154N.sub.2O.sub.10: 1495.1604)

##STR00079##

[0267] Following the procedure described for general procedure of Fmoc deprotection, N-Fmoc-N-MeLeu-D-morphPhLac-O-TAGa (628 mg, 0.417 mmol) was converted to 15 (530 mg, 100%) as a colorless powder.

[0268] mp: 49-50° C.

[0269] [α].sub.D.sup.27=+5.7 (c 1.0, CHCl.sub.3)

[0270] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.08 (d, J=8.6 Hz, 2H), 6.80 (d, J=8.6 Hz, 2H), 6.51 (s, 2H), 5.24 (dd, J=4.0, 9.7 Hz, 1H), 5.07 (q, J=12.0 Hz, 2H), 3.94 (m, 6H), 3.85 (m, 4H), 3.18 (m, 2H), 3.10 (m, 4H), 3.00 (d, J=10.3, 14.3 Hz, 1H), 2.21 (s, 3H), 1.76 (m, 6H), 1.47 (m, 6H), 1.34-1.25 (complex m, 87H), 0.88 (t, J=6.9 Hz, 9H), 0.80 (d, J=6.9 Hz, 3H), 0.79 (d, J=6.9 Hz, 3H).

[0271] HRMS (FAB, NBA matrix) m/z: 1274.0986 [(M+H).sup.+, calcd for C.sub.81H.sub.145N.sub.2O.sub.8: 1274. 1001]

##STR00080##

[0272] To a stirred solution of 15 (530 mg, 0.417 mmol) in CH.sub.2Cl.sub.2 (8.4 mL) was added 0.2 M toluene solution of unit 1 (0.22 mL, 0.44 mmol), N,N-diisopropylethylamine (0.212 mL, 1.25 mmol), and PyBroP (291 mg, 0.62 mmol) at room temperature. After stirring for 16 h, the reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford 16 (670 mg, 95%) as a colorless powder.

[0273] mp: 48-49° C.

[0274] [α].sub.D.sup.27=−12.4 (c 1.0, CHCl.sub.3)

[0275] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.76 (m, 2H), 7.61 (m, 2H), 7.38 (m, 2H), 7.30 (m, 2H), 7.02 (m, 2H), 6.74 (m, 2H), 6.49 (2 s, rotamer, 2H), 5.38-5.22 (complex m, 2H), 5.15-4.98 (complex m, 4H), 4.47 (complex m, 3H), 3.94 (m, 6H), 3.81 (m, 4H), 3.12-2.78 (complex m, 12H), 1.82-1.56 (complex m, 9H), 1.53-1.40 (complex m, 8H), 1.34-1.26 (complex m, 88H), 0.98-0.75 (complex m, 21H).

[0276] HRMS (FAB, NBA matrix) m/z: 1694.2828 (M.sup.+, calcd for C.sub.106H.sub.171N.sub.3O.sub.13: 1694.2812)

##STR00081##

[0277] Following the procedure described for general procedure of TAGa cleavage, 16 (376 mg, 0.222 mmol) was converted to 17. In the case of this substrate, the reaction required longer time than that of the general condition of TAGa cleavage (ca. 1 h). The reaction of 16 in 50% TFA/CH.sub.2Cl.sub.2 at room temperature was needed to stir for 8 h to consume all of starting material, and gave product 17 (178 mg, 0.222 mmol) as a crude oil, which was used next action without further purification.

##STR00082##

[0278] Following the procedure described for general procedure of Fmoc deprotection, 16 (290 mg, 0.171 mmol) was converted to 18 (251 mg, 100%) as a colorless powder.

[0279] mp: 43-45° C.

[0280] [α].sub.D.sup.25=−2.8 (c 1.0, CHCl.sub.3)

[0281] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.07 (d, J=8.6 Hz, 2H), 6.79 (d, J=8.6 Hz, 2H), 6.49 (s, 2H), 5.46 (q, J=6.9 Hz, 1H), 5.33 (dd, J=5.2, 10.9 Hz, 1H), 5.17 (dd, J=5.2, 7.5 Hz, 1H), 5.06 (m, 2H), 3.95 (m, 6H), 3.84 (m, 4H), 3.33 (t, J=7.5 Hz, 1H), 3.11-3.06 (complex m, 6H), 2.82 (2 s, rotamer 4:1, 3H), 2.40 (s, rotamer, 3H), 1.82-1.59 (complex m, 10H), 1.52-1.43 (complex m, 8H), 1.34-1.25 (complex m, 87H), 0.97-0.86 (complex m, 21H).

[0282] HRMS (FAB, NBA matrix+NaI) m/z: 1473.2222 [(M+H).sup.+, calcd for C.sub.91H.sub.162N.sub.3O.sub.11: 1473.2209]

##STR00083##

[0283] To a stirred solution of 18 (251 mg, 0.171 mmol) in CH.sub.2Cl.sub.2 (3.4 mL) was added 17 (178 mg, 0.222 mmol), N,N-diisopropylethylamine (87 μL, 0.513 mmol), and PyBroP (120 mg, 0.257 mmol) at room temperature. After stirring at 46 h, the reaction mixture was crystallized by the procedure described in synthesis of N-Fmoc-N-MeLeu-D-Lac-O-TAGa to afford 19 (350 mg, 91%) as a colorless powder.

[0284] mp: 50-52° C.

[0285] [α].sub.D.sup.25=−25.5 (c 1.0, CHCl.sub.3)

[0286] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.75 (m, 2H), 7.62 (m, 2H), 7.38 (m, 2H), 7.30 (m, 2H), 7.06 (m, 4H), 6.77 (m, 4H), 6.49 (2 s, rotamer, 2H), 5.42-4.98 (complex m, 10H), 4.73-4.20 (complex m, 3H), 3.94 (m, 6H), 3.84 (m, 8H), 3.17-2.66 (complex m, 24H), 1.80-1.64 (complex m, 14H), 1.46-1.25 (complex m, 100H), 1.00-0.77 (complex m, 33H).

[0287] HRMS (FAB, NBA matrix) m/z: 2276.5940 [(M+Na).sup.+, calcd for C.sub.136H.sub.216N.sub.6O.sub.20Na: 2276.5967]

##STR00084##

[0288] Following the procedure described for general procedure of Fmoc deprotection, 19 (114 mg, 0.0505 mmol) was converted to the corresponding amine (103 mg, 100%) as a colorless powder.

[0289] mp: 45-47° C.

[0290] [α].sub.D.sup.25=−19.6 (c 1.0, CHCl.sub.3)

[0291] .sup.1H-NMR (500 MHz, CDCl.sub.3) δ: 7.76 (m, 4H), 6.79 (m, 4H), 6.48 (s, 2H), 5.50-4.96 (complex m, 9H), 3.94 (m, 6H), 3.83 (m, 8H), 3.30 (m, 1H), 3.16-2.74 (complex m, 21H), 2.38 (m, 3H), 1.80-1.55 (complex m, 9H), 1.47-1.24 (complex m, 105H), 1.00-0.81 (complex m, 33H).

[0292] HRMS (FAB, NBA matrix) m/z: 2032.5468 [(M+H).sup.+, calcd for C.sub.12H.sub.207N.sub.6O.sub.18: 2032.5467]

##STR00085##

[0293] Following the procedure described for general procedure of TAGa cleavage, N-MeLeu-D-Lac-N-MeLeu-D-morphPhLac-N-MeLeu-D-Lac-N-MeLeu-D-morph-PhLac-O-TAGa (102 mg, 0.0502 mmol) was converted to the corresponding carboxylic acid. In the case of this substrate, the reaction required longer time than that of the general condition of TAGa cleavage (ca. 1 h). The reaction in 50% TFA/CH.sub.2Cl.sub.2 at room temperature was needed to stir for 5 h to consume all of starting material, and gave desired product (˜0.0502 mmol) as a crude oil, which was used next reaction without further purification.

[0294] Emodepside

##STR00086##

[0295] To a crude of carboxylic acid (0.0502 mmol) in CH.sub.2Cl.sub.2 (10 ml, 0.005 M) was added N,N-diisopropylethylamine (60 μL, 0.351 mmol) and PyBOP (52 mg, 0.175 mmol) at room temperature. After stirring for 44 h, the reaction mixture was quenched with saturated aqueous NaHCO.sub.3(10 mL) at 0° C. and this mixture was extracted with CHCl.sub.3 (20 ml×3). The combined organic layers were washed with 10% aqueous NaHSO.sub.4 (60 ml) and brine (60 ml), dried over Na.sub.2SO.sub.4, filtered and concentrated in vacuo. The crude was purified by column chromatography on silica gel (CHCl.sub.3 MeOH=400:1 to 100:1) to provide Emodepside (25 mg, 44% for 2 steps) as alight brown solid.

[0296] All physical data for synthetic Emodepside matched with the data of authentic compound.

Comparative Example 1

[0297] A tag analogous to TAGa, but with C.sub.12 instead of C.sub.18 alkyl chains (C12-TAG), was prepared and coupled with N-Fmoc-N-MeLeu-D-Lac-OH (unit 1) according to the following reaction scheme:

##STR00087##

[0298] Purification via silica gel chromatography was necessary after each reaction step. The compounds 2, C12-TAG and 3 did not crystallize in methanol. This is in contrast to, for example, the synthetic procedure for N-Fmoc-N-MeLeu-D-Lac-O-TAGa (section 2.1 above). The C12-TAG in this comparative example was not suitable for the intended tag-assisted synthesis and the further functionalization of compound 3 was not investigated further.

Comparative Example 2

[0299] The commercially available C1-TAG was coupled with N-Fmoc-N-MeLeu-D-Lac-OH (unit 1) according to the following reaction scheme:

##STR00088##

[0300] Purification via column chromatography was necessary after the reaction step. The compounds C1-TAG and 6 did not crystallize in methanol. The C1-TAG in this comparative example was not suitable for the intended tag-assisted synthesis and the further functionalization of compound 6 was not investigated further.