SULFONYLUREA RING SUBSTITUTED MONOCYCLIC beta-LACTAM ANTIBIOTICS

Abstract

Sulfonylurea ring substituted monocyclic β-lactam antibiotics, and specifically relating to a compound represented by formula (I), a pharmaceutically acceptable salt or a stereoisomer thereof, and an application thereof in the preparation of medicaments for treating diseases related to bacterial infections.

##STR00001##

Claims

1. A compound of formula (I), an isomer thereof or a pharmaceutically acceptable salt thereof, ##STR00037## Wherein L.sub.1 is selected from —CH.sub.2CH.sub.2—, —CH.sub.2CH.sub.2CH.sub.2—, —C(═O)CH.sub.2—, —C(═O)CH.sub.2CH.sub.2—, and —CH.sub.2C(═O)CH.sub.2—; L.sub.2 is selected from a single bond and —CH.sub.2—; R.sub.1 is selected from H, CN, and C.sub.1-3 alkyl, wherein C.sub.1-3 alkyl is optionally substituted with one, two or three R.sub.a; R.sub.2 and R.sub.3 are each independently selected from H, OH, C.sub.1-6 alkyl, C.sub.1-6 alkoxy, —CH.sub.2—O—C(═O)—C.sub.1-3 alkyl, —CH.sub.2—NH—C.sub.1-3 alkyl, —CH.sub.2—NH—C(═NH)NH.sub.2, and —CH.sub.2—NH—C(═O)—C.sub.1-3 alkyl, wherein C.sub.1-6 alkyl, C.sub.1-6 alkoxy, —CH.sub.2—O—C(═O)—C.sub.1-3 alkyl, —CH.sub.2—NH—C.sub.1-3 alkyl, —CH.sub.2—NH—C(═NH)NH.sub.2, and —CH.sub.2—NH—C(═O)—C.sub.1-3 alkyl are optionally substituted with one, two or three R.sub.b; R.sub.4, R.sub.5, R.sub.6, and R.sub.7 are each independently selected from H, F, Cl, Br, I, CH.sub.3, CH.sub.2CH.sub.3, CF.sub.3, CHF.sub.2, and CH.sub.2F; R.sub.a and R.sub.b are each independently selected from F, Cl, Br, I, OH, CN, COOH, CH.sub.3, CH.sub.2CH.sub.3, CH.sub.2CH.sub.2CH.sub.3, CH(CH.sub.3).sub.2, OCH.sub.3, OCF.sub.3, CHF.sub.2, CH.sub.2F, and NH.sub.2.

2. The compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.1 is selected from H, CN, and CH.sub.3.

3. The compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.2 and R.sub.3 are each independently selected from H, OH, C.sub.1-3 alkyl, C.sub.1-3 alkoxy, ##STR00038## wherein C.sub.1-3 alkyl, C.sub.1-3 alkoxy, ##STR00039## are optionally substituted with one, two and three R.sub.b.

4. The compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 3, wherein R.sub.2 and R.sub.3 are each independently selected from H, CH.sub.3, ##STR00040##

5. The compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 1, wherein the structural unit ##STR00041## is selected from ##STR00042##

6. The compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 1, wherein the structural unit ##STR00043## is selected from ##STR00044##

7. The compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 1, wherein the compound is selected from ##STR00045## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, and R.sub.7 are as defined in claim 1.

8. The compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 7, wherein the compound is selected from ##STR00046## wherein R.sub.1, R.sub.2, R.sub.4, R.sub.5, R.sub.6, and R.sub.7 are as defined in claim 7.

9. A compound of the following formula, an isomer thereof or a pharmaceutically acceptable salt thereof, which is selected from ##STR00047##

10. The compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 9, which is selected from ##STR00048##

11. An application of the compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 1 in the preparation of medicaments for treating diseases related to bacterial infections.

12. An application of the compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 8 in the preparation of medicaments for treating diseases related to bacterial infections.

13. An application of the compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 9 in the preparation of medicaments for treating diseases related to bacterial infections.

14. An application of the compound, the isomer thereof or the pharmaceutically acceptable salt thereof according to claim 10 in the preparation of medicaments for treating diseases related to bacterial infections.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] The present disclosure is described in detail by the embodiments below, but it does not mean that there are any adverse restrictions to the present disclosure. The compounds of the present disclosure can be prepared by a variety of synthetic methods known to those skilled in the art, including the specific embodiments listed below, embodiments resulting from their combination with other chemical synthesis methods, and equivalent substitutions known to those skilled in the art, preferred embodiments including, but not limited to, embodiments of the present disclosure. It will be apparent to those skilled in the art that various variations and improvements can be made to specific embodiments of the present disclosure without departing from the spirit and scope of the present disclosure.

[0060] General Synthetic Routes:

##STR00021##

[0061] PG.sub.1 is a common amine protecting group, such as triphenylmethyl, tert-butoxycarbonyl, and the like; PG.sub.2 is a common carboxyl protecting group, such as diphenyl methyl, tert-butyl, and the like. All other variables are as defined in the present disclosure, and the compound of formula (I) can be prepared from the reaction intermediate SM-1 in three steps. Specifically, step 1 is an acid-amine condensation reaction, usually performed under the action of a condensing agent such as HOBT, EDCI, HATU, HBTU, DCC and an appropriate amount of alkali at a low temperature such as 0-20° C.; step 2 is a sulfonic acid introducing reaction, usually performed by reacting substrate SM-2 under the action of a sulfonating agent such as DMF SO.sub.3, pyridine SO.sub.3 in DMF solvent at a low temperature, preferably at a temperature ranging from 0-10° C.; step 3 is a deprotection reaction, usually performed under the action of an acid, commonly used acids including trifluoroacetic acid, formic acid, and the like, with dichloromethane as solvent, anisole helping to remove the protecting group, and the preferred reaction temperature ranging from −10-10° C.

PREPARATION OF INTERMEDIATE

Synthesis Route 1 of Intermediate

[0062] ##STR00022## ##STR00023##

[0063] For the synthesis of intermediate A-6, see the reference (Org. Process Res. Dev. 2018, 22, 212), and the racemate A-5 was chemically resolved to obtain the single chiral compound A-6.

Synthesis Route 2 of Intermediate

[0064] ##STR00024##

[0065] Step 1: Preparation of Compound B-2

[0066] A-6 (3.8 g, 10.40 mmol, 1 eq) and triethylamine (2.10 g, 20.80 mmol, 2.89 mL, 2 eq) were dissolved in a dichloromethane (30 mL) solution, a solution of (chlorosulfonyl)carbamate acid benzyl ester (2.60 g, 10.40 mmol, 1 eq) in dichloromethane (30 mL) was added dropwise at 0° C., and the mixture was stirred at 10-20° C. for 1 hour. The reaction mixture was washed with water (40 mL), stirred for 5 minutes, and extracted with dichloromethane (30 mL). The combined organic phase was washed with brine (30 mL), dried over anhydrous Na.sub.2SO.sub.4, filtered, and concentrated in vacuo to obtain compound B-2 (6.0 g) LCMS (ESI) m/z: 579.2 (M+1).

[0067] Step 2: Preparation of Compound B-3

[0068] Compound B-2 (6 g, 10.37 mmol, 1 eq) was dissolved in MeCN (60 mL), and 1,2-dibromoethane (3.90 g, 20.74 mmol, 1.56 mL, 2 eq) and K.sub.3PO.sub.4 (4.40 g, 20.74 mmol, 2 eq) were added to the solution at a time under N.sub.2 protection at 10-20° C. The mixture was stirred at 60° C. for 14 hours, 1,2-dibromomethane (1.95 g, 10.37 mmol, 782.32 μL, 1 eq) was supplementarily added, and the mixture was stirred at 90° C. for another 8 hours. The mixture was filtered and concentrated under reduced pressure to obtain a residue. The residue was purified by silica gel chromatography (PE/EA=4:1 to 2:1, then dichloromethane/PE=50:1 to 20:1). Compound B-3 was obtained. LCMS (ESI) m/z: 477 (M+23); 399 (M-56+1).

[0069] Step 3: Preparation of Compound B-4

[0070] Compound B-3 (3.4 g, 5.62 mmol, 1 eq) was dissolved in H.sub.2O (45 mL) and MeCN (90 mL), and dipotassium hydrogen phosphate (3.92 g, 22.49 mmol, 4 eq) and potassium persulfate (6.84 g, 25.30 mmol, 4.5 eq) were added at a time under nitrogen protection at 25° C. The mixture was stirred at 100° C. for 0.5 hour. 50 mL of sodium bicarbonate aqueous solution was added to the reaction mixture and it was extracted with ethyl acetate (100 mL solution). The combined organic phase was washed with brine, dried over anhydrous Na.sub.2SO.sub.4, filtered, and concentrated in vacuo. The residue was purified by silica gel chromatography (petroleum ether/ethyl acetate (V/V, the same below)=4:1 to 1:3) to obtain compound B-4. LCMS (ESI) m/z: 399.1 (M-56+1).

[0071] Step 4: Preparation of Compound B-5

[0072] Compound B-4 (1.6 g, 3.52 mmol, 1 eq) and Pd/C (320 mg, 10% purity) were dissolved in EtOH (30 mL), and stirred at 25° C. under H.sub.2 (15 psi) for 2 hours. It was filtered, and the filtrate was concentrated in vacuo. B-5 was obtained and used directly in the next reaction.

[0073] Step 5: Preparation of Compound B-6

[0074] Compound B-5 was dissolved in dichloromethane (5 mL) solution, and TFA (8.47 g, 74.28 mmol, 5.50 mL, 21.63 eq) was added at a time under nitrogen protection at 0° C. The mixture was stirred at 25° C. for 1 hour. The reaction mixture was concentrated in vacuo to obtain the trifluoroacetate of compound B-6. LCMS (ESI) m/z: 242.9 (M+23).

Synthesis Route 3 of Intermediate

[0075] ##STR00025##

[0076] Step 1: Preparation of Compound C-2

[0077] Compound A-6 (500 mg, 1.37 mmol, 1 eq) was dissolved in acetonitrile (20 mL), and 2-bromoethanol (341.97 mg, 2.74 mmol, 194.30 μL, 2 eq) and K.sub.3PO.sub.4 (580.88 mg, 2.74 mmol, 2 eq) were added at a time under nitrogen protection at 25-30° C. The mixture was stirred at 90° C. for 12 hours, the mixture was filtered, the filtrate was washed with brine (30 mL), the mixture was extracted with EtOAc (80 mL), and the organic layer was dried over Na.sub.2SO.sub.4, filtered, and concentrated in vacuo. The residue was purified by column chromatography (SiO.sub.2, petroleum ether/ethyl acetate=3:1 to 0:1). Compound C-2 was obtained. LCMS (ESI) m/z: 410.2 (M+1).

[0078] Step 2: Preparation of Compound C-1

[0079] Compound A-6 (410.0 mg, 1.12 mmol, 1 eq) was dissolved in 1,2-dichloroethane (20 mL) and MeOH (2 mL), 2-[tert-butyl (dimethyl) silyl] oxyacetaldehyde (293.36 mg, 1.68 mmol, 320.62 μL, 1.5 eq) was added under nitrogen protection at 30° C., the mixture was adjusted to pH=5 with AcOH (67.38 mg, 1.12 mmol, 64.17 μL, 1 eq) and stirred for 30 minutes, then cooled to 0-10° C., NaBH(OAc).sub.3 (832.28 mg, 3.93 mmol, 3.5 eq) was added, and the mixture was stirred for another 18 h. A saturated aqueous solution of NaHCO.sub.3 (5 mL) was added to the solution, and it was extracted with DCM (10 mL). The combined organic phase was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated in vacuo. The concentrate was purified by silica gel chromatography (petroleum ether/ethyl acetate=10:1 to 0:1) to obtain compound C-1. LCMS (ESI) m/z: 524.5 (M+1).

[0080] Step 3: Preparation of Compound C-2

[0081] A solution of tetrabutylammonium fluoride in tetrahydrofuran (1 M, 2.83 mmol, 2 eq) was added to a solution of compound C-1 (740 mg, 1.41 mmol, 1 eq) in THF (10 mL) under nitrogen protection at 0° C., and then stirred for 1 hour. 20 mL saturated brine was added to the mixture, the organic phase was separated, it was extracted with EA (20 mL, 3), and the collected organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The concentrate was purified by silica gel chromatography (petroleum ether/ethyl acetate=5:1 to 0:1) to obtain compound C-2. LCMS(ESI) m/z: 410.3 (M+1).

[0082] Step 4: Preparation of Compound B-3

[0083] N-(triethylaminosulfonyl) carbamate acid benzyl ester (synthetized in reference to Chem. Eur. J. 2004, 10, 5581-5606) (2575.3 mg, 2.78 mmol, 3 eq) was added to a solution of compound C-2 (380 mg, 928.02 μmol, 1 eq) in THF (10 mL) under nitrogen at 25° C., and then stirred at 75° C. for 4 hours. 10 mL of water was added to the mixture, it was extracted with EA (20 mL), and the organic phase was washed with 20 mL of brine, dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The concentrate was purified by silica gel chromatography (petroleum ether/ethyl acetate=5:1 to 0:1) to obtain compound B-3. .sup.1H NMR (400 MHz, CDCl.sub.3) δ=7.35-7.28 (m, 3H), 7.27-7.20 (m, 2H), 7.17 (s, 5H), 6.38-6.33 (m, 1H), 5.23 (s, 1H), 5.14-5.00 (m, 2H), 3.71 (d, J=4.3 Hz, 5H), 3.38-3.29 (m, 2H), 3.18-2.99 (m, 2H), 1.48 (s, 20H), 1.37-1.29 (m, 9H), 1.28-1.05 (m, 4H), 0.96-0.69 (m, 2H); LCMS(ESI) m/z: 605.4 (M+1).

Synthesis Route 4 of Intermediate

[0084] ##STR00026##

[0085] Step 1: Preparation of Compound D-2

[0086] MgSO.sub.4 (4.60 g, 38.22 mmol, 0.75 eq) and manganese dioxide (15.50 g, 178.35 mmol, 3.5 eq) were added to the mixture of benzophenone hydrazone (10 g, 50.96 mmol, 1 eq) and dichloromethane (100 mL) at a time under nitrogen protection at 0-10° C. The reaction mixture was stirred at 0-30° C. for 1 hour. The mixture was filtered and the filtrate was added to a mixture of D-1 (4.94 g, 48.42 mmol, 0.95 eq) in MeOH (30 mL) under nitrogen protection at 0-10° C. The mixture was stirred at 0-30° C. for 2 hours. The mixture was concentrated in vacuo. The compound D-2 was obtained by recrystallization from PE (150 mL). .sup.1H NMR (400 MHz, CDCl.sub.3) δ 7.20-7.30 (m, 10H), 6.85 (s, 1H), 1.27-1.36 (m, 2H), 1.09-1.22 (m, 2H).

[0087] Step 2: Preparation of Compound D-3

[0088] t-BuONa (214.91 mg, 2.24 mmol, 1.2 eq) was added to a mixture of O-diphenylphosphorylhydroxylamine (521.50 mg, 2.24 mmol, 1.2 eq) and compound D-2 (0.5 g, 1.86 mmol, 1 eq) in THF (10 mL) under nitrogen protection at 0-10° C. The reaction mixture was stirred at 0-10° C. for 120 minutes. The reaction solution was washed with 5% brine (30 mL) and stirred for 15 minutes. The insoluble material was filtered, the filter cake was washed with ethyl acetate (10 mL), and the filtrate was extracted with ethyl acetate (20 mL). The combined organic phase was washed with saturated brine (20 mL in combination) and dried over anhydrous sodium sulfate. The EtOAc/THF (60 mL) solution of compound D-3 was obtained, which was directly use in the next reaction.

[0089] Step 3: Preparation of Compound D-4

[0090] 2-oxo-2-[2-(triphenylamino) thiazol-4-yl] acetic acid (617.94 mg, 1.49 mmol, 0.8 eq) was added to the EtOAc/THF solution of compound D-3 (theoretical yield 528 mg, 1.86 mmol, 1 eq, 60 mL) at a time under nitrogen protection at 15-25° C. The mixture was stirred and reacted at 15-25° C. for 8 hours. The reaction mixture was concentrated under reduced pressure at 45° C. to obtain compound D-4. LCMS (ESI) m/z: 680.2 (M+1).

Embodiment 1

Synthesis of Compound 1

[0091] ##STR00027##

[0092] Step 1: Preparation of Compound 1-2

[0093] HATU (1.63 g, 4.28 mmol, 1.3 eq) and TEA (998.97 mg, 9.87 mmol, 1.37 mL, 3 eq) were added to the mixed solution of the trifluoroacetate of compound B-6 (1.1 g, 3.29 mmol, 1 eq) and compound D-4 (2.01 g, 2.96 mmol, 0.9 eq) in DMF (20 mL) at 15° C., and then the reaction mixture was stirred under nitrogen at 15° C. for 8 hours. Water (50 mL) was added to the reaction solution, and the aqueous phase was extracted with ethyl acetate (100 mL acetic acid). The combined organic phase was washed with aqueous NaHCO.sub.3 solution and brine, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The crude product was purified by silica gel chromatography (PE/EA=4:1 to 1:3) to obtain compound 1-2. LCMS (ESI) m/z: 882.2 (M+1).

[0094] Step 2: Preparation of Compound 1-3

[0095] DMF.SO.sub.3 complex (1.35 g, 8.84 mmol, 6 eq) was added to a mixed solution of compound 1-2 (1.3 g, 1.47 mmol, 1 eq) and DMF (15 mL) at a time under nitrogen protection at 0° C. The solution was stirred at 15° C. for 1 hour. Water (20 mL) was added to the solution and it was extracted with ethyl acetate (50 mL). The combined organic phase was washed with water and brine, dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain compound 1-3. LCMS (ESI) m/z: 962.7 (M+1).

[0096] Step 3: Preparation of Compound 1

[0097] Compound 1-3 (400.00 mg, 415.77 μmol, 1 eq) was dissolved in dichloromethane (4 mL), and anisole (89.92 mg, 831.53 μmol, 90.37 μL, 2 eq) and TFA (3.08 g, 27.01 mmol, 2.00 mL, 64.97 eq) were added to the reaction mixture under nitrogen protection at 0° C. The reaction mixture was stirred at 25° C. for 1 hour. Methyl tert-butyl ether (100 mL) was added to the compound to precipitate the solid, it was filtered, and the filter cake was collected. The filter cake was purified by reverse phase HPLC (column: Phenomenex Luna C18 200*40 mm*10 um; mobile phase: [mobile phase A: water (0.1% TFA); mobile phase B: acetonitrile]; the percentage of mobile phase B: 1%-27%, 10 min) to purified the crude product to obtain compound 1. .sup.1H NMR (400 MHz, DMSO-d.sub.6+D.sub.2O) δ=6.96 (s, 1H), 5.39-5.10 (m, 1H), 4.28-4.05 (m, 2H), 3.56-3.42 (m, 1H), 3.36-3.29 (m, 2H), 3.27-3.03 (m, 3H), 1.40 (br d, J=3.9 Hz, 4H); LCMS(ESI) m/z: 553.9 (M+1); 473.9 (M-80+1).

Embodiment 2

Synthesis of Compound 2

[0098] ##STR00028##

[0099] Referring to the preparation process of compound 1, compound 2 was obtained by post processing of reversed-phase HPLC (column: Phenomenex Synergi C18 150 mm*25 mm*10 um; mobile phase: [mobile phase A: water (0.1% TFA; mobile phase B: acetonitrile]; the percentage of mobile phase B %: 1%-25%, 10 min). .sup.1H NMR (400 MHz, DMSO-d.sub.6+D.sub.2O) δ=6.90-6.84 (m, 1H), 5.21 (d, J=5.7 Hz, 1H), 4.22-4.12 (m, 1H), 3.59 (br dd, J=3.2, 14.1 Hz, 2H), 3.31-3.05 (m, 6H), 1.37 (br s, 4H); LCMS(ESI) m/z: 567.5 (M+1).

Embodiment 3

Synthesis of Compound 3

[0100] ##STR00029## ##STR00030## ##STR00031##

[0101] Step 1: Preparation of Compound 3-2

[0102] Compound A-6 (5.7 g, 15.60 mmol, 1 eq), tert-butyl-dimethyl-[[((2R)-oxirane-2-yl] methoxy] silane (3.23 g, 17.16 mmol, 1.1 eq) and diisopropylethylamine (2.32 g, 17.94 mmol, 3.12 mL, 1.15 eq) were dissolved in ethanol (60 mL) under nitrogen protection at 15° C., and then the mixture was stirred at 90° C. for 18 hours. The solution was concentrated in vacuo. The residue was purified by silica gel chromatography (petroleum ether/ethyl acetate=4/1 to 0/1). Compound 3-2 was obtained.

[0103] Step 2: Preparation of Compound 3-3

[0104] Compound 3-2 (4.02 g, 7.26 mmol, 1 eq) and triethylamine (1.47 g, 14.52 mmol, 2.02 mL, 2 eq) was dissolved in dichloromethane (40 mL), the temperature was lowered to 0° C., a solution of (chlorosulfonyl)carbamic acid benzyl ester (1.81 g, 7.26 mmol, 1 eq) in dichloromethane (20 mL) was added dropwise under nitrogen protection, and the mixture was stirred at 0-15° C. for 2 hours. The solution was quenched with water (50 mL) and extracted with dichloromethane (50 mL*3). The combined organic phase was washed with brine (100 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain crude product 3-3.

[0105] Step 3: Preparation of Compound 3-4

[0106] Compound 3-3 (6.30 g, 8.21 mmol, 1 eq) and triethylamine (1.25 g, 12.32 mmol, 1.71 mL, 1.5 eq) were dissolved in dichloromethane (70 mL), the temperature was lowered to 0° C., methanesulfonyl chloride (1.13 g, 9.86 mmol, 762.92 μL, 1.2 eq) was added dropwise under nitrogen protection, and the solution was stirred at 0° C. for 2 hours. The solution was quenched with water (100 mL) and extracted with dichloromethane (100 mL*3). The combined organic phase was washed with brine (100 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain crude product 3-4.

[0107] Step 4: Preparation of Compound 3-5

[0108] Compound 3-4 (13.40 g, 15.86 mmol, 1 eq) and potassium phosphate (4.38 g, 20.61 mmol, 1.3 eq) was mixed in acetonitrile (150 mL) at 15° C., and then the reaction solution was stirred at 80° C. for 2 hours. The filtrate was concentrated in vacuo. The residue was purified by silica gel chromatography (petroleum ether/ethyl acetate=5/1 to 3/1) to obtain compound 3-5.

[0109] Step 5: Preparation of Compound 3-6

[0110] Compound 3-5 (5.00 g, 6.68 mmol, 1 eq), potassium dihydrogen phosphate (4.65 g, 26.70 mmol, 4 eq) and potassium persulfate (8.12 g, 30.04 mmol, 6.02 mL, 4.5 eq) were mixed and dissolved in acetonitrile (240 mL) and water (120 mL) under nitrogen protection at 25° C., and then the solution was heated to 100° C. and stirred for 40 minutes. The solution was cooled, filtered, the filtrate was concentrated in vacuo, then water (50 mL) was added, it was extracted with ethyl acetate (50 mL*3), and the combined organic phase was washed with brine (100 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The residue was purified by silica gel chromatography (petroleum ether/ethyl acetate=4/1 to 2/1). Compound 3-6 was obtained.

[0111] Step 6: Preparation of Compound 3-7

[0112] Compound 3-6 (2.30 g, 3.84 mmol, 1 eq) was dissolved in dichloromethane (30 mL), triethylamine trihydrofluoride (3.72 g, 23.05 mmol, 3.76 mL, 6 eq) was added to the reaction liquid under nitrogen protection at 25° C., and then the solution was stirred at 25° C. for 15 hours. Water (30 mL) was added to the solution for dilution, it was extracted with dichloromethane (30 mL*3), and the combined organic phase was washed with brine (100 mL*2), dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel chromatography (petroleum ether/ethyl acetate=3/1 to 0/1). Compound 3-7 was obtained.

[0113] Step 7: Preparation of Compound 3-8

[0114] Compound 3-7 (700 mg, 1.44 mmol, 1 eq) and triethylamine (190.05 mg, 1.88 mmol, 261.42 μL, 1.3 eq) were dissolved in dichloromethane (20 mL) under nitrogen protection at 0° C., acetyl chloride (136.09 mg, 1.73 mmol, 123.72 μL, 1.2 eq) was added dropwise, and the solution was slowly heated to 25° C. and stirred for 4 hours. The solution was quenched by adding water (10 mL) and extracted with methylene chloride (20 mL*3). The combined organic phase was washed with brine (50 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The residue was purified by silica gel chromatography (petroleum ether/ethyl acetate=3/1 to 0/1). Compound 3-8 was obtained. .sup.1H NMR (400 MHz, CDCl.sub.3) δ=7.46-7.34 (m, 5H), 6.53-6.46 (m, 1H), 5.40-5.31 (m, 2H), 5.06-5.05 (m, 1H), 5.10-5.00 (m, 1H), 4.57-4.47 (m, 1H), 4.41-4.34 (m, 1H), 4.28-4.21 (m, 1H), 4.12-4.06 (m, 1H), 4.18-4.06 (m, 3H), 3.64-3.55 (m, 1H), 3.52-3.43 (m, 1H), 3.39-3.33 (m, 1H), 3.26-3.18 (m, 1H), 2.12-2.09 (m, 3H), 1.50-1.42 (m, 9H).

[0115] Step 8: Preparation of Compound 3-9

[0116] Palladium carbon (130 mg, 189.56 μmol, purity 10%) was added to the solution of compound 3-8 (430 mg, 816.62 μmol, 1 eq) in ethanol (10 mL) under nitrogen protection at 20° C., replaced with hydrogen, and then the solution was stirred under hydrogen pressure (15 Psi) at 20° C. for 2 hours. The solution was filtered, washed with tetrahydrofuran, and the filtrate was concentrated in vacuo. Compound 3-9 is obtained without purification.

[0117] Step 9: Preparation of Compound 3-10

[0118] Compound 3-9 (280 mg, 713.51 μmol, 1 eq) was dissolved in dichloromethane (1 mL) under nitrogen protection at 0° C., and TFA (1.54 g, 13.51 mmol, 1 mL, 18.93 eq) was added to the solution. The reaction solution was heated to 25° C. and reacted for 2 hours. The reaction solution was concentrated in vacuo. The crude product of the trifluoroacetate of 3-10 was obtained.

[0119] Step 10: Preparation of Compound 3-11

[0120] The trifluoroacetate of compound 3-10 (290 mg, 713.70 μmol, 1 eq) was dissolved in DMF (10 mL) under nitrogen protection at 25° C., and compound D-4 (485.16 mg, 713.70 μmol, 1 eq), HATU (352.78 mg, 927.81 μmol, 1.3 eq) and triethylamine (216.66 mg, 2.14 mmol, 298.02 μL, 3 eq) were added to the reaction solution. The solution was stirred for 4 hours. Then 10 mL of water was added to the solution, and the aqueous phase was extracted with ethyl acetate (20 mL×3). The combined organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography (PE/EA=3/1 to 1/3) to obtain compound 3-11. LCMS: 954.3 (M+1).

[0121] Step 11: Preparation of Compound 3-12

[0122] Compound 3-11 (100 mg, 104.81 μmol, 1 eq) was dissolved in DMF (3 mL) under nitrogen protection at 0° C., and N, N-dimethylformamide sulfur trioxide complex (96.32 mg, 628.88 μmol, 6 eq) was added to the reaction solution. The reaction was carried out at 25° C. for 2 hours. Water (5 mL) was added to the reaction solution, it was extracted with ethyl acetate (10 mL*3), and the combined organic phase was washed with brine (20 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain crude 3-12. LCMS: 1034.3 (M+1).

[0123] Step 12: Preparation of Compound 3

[0124] Compound 3-12 (60 mg, 58.02 μmol, 1 eq) was dissolved in dichloromethane (0.8 mL) under nitrogen protection at 0° C., anisole (62.74 mg, 580.19 μmol, 63.06 μL, 10 eq) and TFA (1.23 g, 10.80 mmol, 0.8 mL, 186.23 eq) were added, and then the reaction solution was stirred under nitrogen protection at 25° C. for 1 hour. The solution was washed with n-heptane (5 mL*2), the supernatant was decanted, then it was pulped with cooled MTBE (20 mL), filtered, the filter cake was washed with MTBE (5 mL), and the filter cake was purified by reverse phase HPLC (column: Phenomenex Luna C18 150*25 mm*10 μm; mobile phase: [mobile phase A: water (0.1% TFA); mobile phase B: acetonitrile]; the percentage of mobile phase B: 10%-30%, 10 min) to obtain compound 3. .sup.1H NMR (400 MHz, DMSO-d6) δ=6.81 (s, 1H), 5.25 (d, J=5.5 Hz, 1H), 4.18-4.10 (m, 1H), 3.96-3.88 (m, 2H), 3.76-3.66 (m, 1H), 3.63-3.46 (m, 2H), 3.05 (br dd, J=8.3, 13.6 Hz, 1H), 2.95-2.69 (m, 2H), 2.01-1.96 (m, 3H), 1.42-1.28 (m, 4H); LCMS(ESI) m/z: 626 (M+1); 546 (M-80+1).

Embodiment 4

Synthesis of Compound 4

[0125] ##STR00032## ##STR00033## ##STR00034##

[0126] Step 1: Preparation of Compound 4-2

[0127] Compound A-6 (5 g, 13.68 mmol, 1 eq), (S)-2-(oxirane-2-ylmethyl) isoindoline-1,3-dione (1.95 g, 9.58 mmol, 0.7 eq) and lithium perchlorate (4.37 g, 41.05 mmol, 1.80 mL, 3 eq) were mixed with acetonitrile (30 mL), and the reaction solution was stirred at 60° C. for 3.5 hours. The solution was quenched with 100 mL of water, then extracted with ethyl acetate (100 mL*3), and the combined organic layer was washed with water (100 mL*2) and brine (100 mL*2), dried over sodium sulfate, filtered, and concentrated in vacuo. It was Purified by flash column chromatography on silica gel (PE/EA/DCM=5/1/1 to DCM/MeOH=10/1). The residue was pulped in DCM:EA=1:1 (80 mL) for 16 hours, a white solid was formed, and the solid was collected by filtration and washed with EA (10 mL*2). The filter cake was collected to obtain compound 4-2. LCMS (ESI) m/z: 569.3 (M+1).

[0128] Step 2: Preparation of Compound 4-3

[0129] A solution of (chlorosulfonyl)carbamic acid benzyl ester (1.84 g, 7.39 mmol, 1.5 eq) in DCM (5 mL) was added dropwise to a solution of compound 4-2 (2.8 g, 4.92 mmol, 1 eq) and triethylamine (996.56 mg, 9.85 mmol, 1.37 mL, 2 eq) in DCM (20 mL) under nitrogen protection at 0° C., and stirred for 1 hour. The reaction was quenched with 50 mL of water, then extracted with DCM (50 mL*2), and the organic layer was washed with water (100 mL*2) and brine (100 mL), dried over sodium sulfate, filtered, and concentrated in vacuo to obtain crude product 4-3. LCMS (ESI) m/z: 726.2 (M-55).

[0130] Step 3: Preparation of Compound 4-4

[0131] Methanesulfonyl chloride (700.35 mg, 6.11 mmol, 473.21 μL, 1 eq) was added dropwise to a solution of compound 4-3 (4.78 g, 6.11 mmol, 1 eq) and triethylamine (804.26 mg, 7.95 mmol, 1.11 mL, 1.3 eq) in DCM (40 mL) under nitrogen protection at 0° C., and the reaction solution was stirred for 1 hour after adding. The reaction was quenched with water (50 mL), then it was extracted with DCM (50 mL*2), and the organic layer was washed with water (100 mL*2) and brine (100 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain compound 4-4. LCMS (ESI) m/z: 804.2 (M-55).

[0132] Step 4: Preparation of Compound 4-5

[0133] Compound 4-4 (5.32 g, 6.19 mmol, 1 eq) and potassium phosphate (1.71 g, 8.04 mmol, 1.3 eq) were mixed with acetonitrile (80 mL), and the mixture was stirred under nitrogen protection at 60° C. for 16 hours. The mixture was filtered and the filtrate was concentrated in vacuo to obtain compound 4-5. LCMS (ESI) m/z: 708.2 (M-55).

[0134] Step 5: Preparation of Compound 4-6

[0135] Compound 4-5 (2.94 g, 3.85 mmol, 1 eq) was dissolved in acetonitrile (100 mL) and water (30 mL) under nitrogen protection at 0° C., a solution of cerium ammonium nitrate (4.22 g, 7.70 mmol, 3.84 mL, 2 eq) in water (20 mL) was added dropwise to the reaction solution, and then stirred at 0-25° C. for 5 hours. 100 mL of water was added to the reaction solution, then it was extracted with EA (100 mL*2), and the organic layer was washed with water (100 mL*2) and brine (100 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. Compound 4-6 was obtained by purification with silica gel column chromatography (PE/EA=5/1 to 1/1, 20% DCM). LCMS (ESI) m/z: 558.2 (M-55).

[0136] Step 6: Preparation of Compound 4-7

[0137] Compound 4-6 (1.42 g, 2.31 mmol, 1 eq) and Pd/C (150 mg, 10% purity) were mixed with ethanol (40 mL), stirred under hydrogen (15 psi) at 20-30° C. for 15 hours. The mixture was filtered and the filtrate was concentrated in vacuo to obtain compound 4-7.

[0138] Step 7: Preparation of Compound 4-8

[0139] Trifluoroacetic acid (12.32 g, 108.05 mmol, 8 mL, 43.17 eq) was added to a solution of compound 4-7 (1.2 g, 2.50 mmol, 1 eq) in DCM (16 mL) under nitrogen protection at 0° C., and stirred at 0° C. for 1 hour. The solution was concentrated in vacuo to obtain a crude product of the trifluoroacetate of 4-8.

[0140] Step 8: Preparation of Compound 4-9

[0141] HATU (1.30 g, 3.42 mmol, 1.3 eq) and diisopropylethylamine (1.02 g, 7.89 mmol, 1.37 mL, 3 eq) were added to a mixed solution of the trifluoroacetate of compound 4-8 (1.3 g, 2.63 mmol, 1 eq) and compound D-4 (1.79 g, 2.63 mmol, 1 eq) in DMF (15 mL), and then stirred at 20-30° C. for 1 hour. The solution was poured into 100 mL of water, extracted with DCM (100 mL*2), and the organic layer was washed with water (100 mL) and brine (100 mL), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. Compound 4-9 was obtained by purification with silica gel column chromatography (DCM/EA=1/0 to 1/2). LCMS (ESI) m/z: 1041.4 (M+1).

[0142] Step 9: Preparation of Compound 4-10

[0143] Compound 4-9 (1.22 g, 1.04 mmol, 1 eq) and hydrazine hydrate (265.13 mg, 5.19 mmol, 257.40 μL, 98% purity, 5 eq) were mixed with ethanol (30 mL), and the mixed solution was stirred at 30° C. for 4 hours. The solution was poured into 250 mL of water, extracted with DCM (150 mL*3), and the organic layer was washed with brine (200 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The concentrate was purified by flash column chromatography on silica gel (DCM/MeOH=50/1 to 20/1) to obtain 4-10. LCMS (ESI) m/z: 911.4 (M+1).

[0144] Step 10: Preparation of Compound 4-11

[0145] A solution of Boc.sub.2O (45.16 mg, 206.90 μmol, 47.53 μL, 1.3 eq) in DCM (0.5 mL) was added to a mixed solution of compound 4-10 (145 mg, 159.16 μmol, 1 eq) and triethylamine (40.26 mg, 397.89 μmol, 55.38 μL, 2.5 eq) in DCM (5 mL) under nitrogen protection at 0° C., and stirred for 1 hour. 10 mg of Boc.sub.2O was added, and it was stirred at 25-30° C. for 1 hour. The solution was diluted with DCM (10 mL), then washed with brine (10 mL*2), and the organic layer was dried over Na.sub.2SO.sub.4, filtered, and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (PE/EA=2/1 to 0/1) to obtain compound 4-11. LCMS (ESI) m/z: 1011.5 (M+1).

[0146] Step 11: Preparation of Compound 4-12

[0147] N,N-dimethylformamide sulfur trioxide complex (59.07 mg, 385.69 μmol, 3 eq) was added to a solution of compound 4-11 (130 mg, 128.56 μmol, 1 eq) in DMF (2 mL) at 25° C. The reaction solution was reacted at 25° C. for 1 hour. 10 mL of water was added to the solution, and it was extracted with ethyl acetate (20 mL×3). The combined organic phase was washed with brine (50 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. Compound 4-12 was obtained. LCMS (ESI) m/z: 1091.4 (M+H).

[0148] Step 12: Preparation of Compound 4

[0149] Trifluoroacetic acid (1.54 g, 13.51 mmol, 1 mL, 98.26 eq) was added to a solution of compound 4-12 (150 mg, 137.46 μmol, 1 eq) and anisole (29.73 mg, 274.92 μmol, 29.88 μL, 2 eq) in DCM (1 mL) at 0° C. The mixture was then stirred at 25° C. for 1 hour. The temperature was lowered to 0° C., n-heptane (6 mL*3) was added to the mixture, the supernatant was decanted, then it was pulped with cooled MTBE (4 mL), and then the solution was filtered under the protection of N.sub.2. The crude product was purified by reverse phase HPLC (column: Waters Atlantis T3 150 mm*30 mm*5 μm; mobile phase: [mobile phase A: water (0.1% TFA); mobile phase B: acetonitrile]; the percentage of mobile phase B: 5%-35%, 10 min) to obtain the trifluoroacetate of compound 4. .sup.1H NMR (400 MHz, DMSO-d.sub.6+D.sub.2O) δ=6.86 (s, 1H), 5.27-5.19 (m, 1H), 4.23-4.16 (m, 1H), 3.73-3.59 (m, 2H), 3.40-3.33 (m, 1H), 3.20-3.06 (m, 2H), 3.03-2.82 (m, 3H), 1.36 (br s, 4H); LCMS(ESI) m/z: 583.0 (M+1).

Embodiment 5

Synthesis of Compound 5

[0150] ##STR00035##

[0151] Step 1: Preparation of Compound 5-2

[0152] Compound 4-10 (87 mg, 1 eq) and (E)-tert-butyl (((tert-butoxycarbonyl)amino)(1H-pyrazol-1-yl)methylene)carbamate (35.56 mg, 114.59 μmol, 1.2 eq) were mixed with acetonitrile (5 mL) at 20-25° C., triethylamine (24.16 mg, 238.73 μmol, 33.23 μL, 2.5 eq) was added dropwise to the mixture, then magnesium sulfate (53.22 mg, 442.14 μmol, 4.63 eq) was added, and it was stirred at 20-25° C. for 20 hours. The mixture was filtered, the filtrate was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (petroleum ether/ethyl acetate=10/1 to DCM/MeOH=10/1) to purify the crude product to obtain compound 5-2. LCMS (ESI) m/z: 1153.5 (M+1).

[0153] Step 2: Preparation of Compound 5-3

[0154] Compound 5-2 (85 mg, 73.70 μmol, 1 eq) was dissolved in DMF (2 mL) under nitrogen protection at 25° C., N,N-dimethylformamide sulfur trioxide complex (33.86 mg, 221.10 μmol, 3 eq) was added to the solution, and then stirred at 25° C. for 1 hour. 10 mL of water was added to the reaction solution, and it was extracted with ethyl acetate (20 mL×3). The combined organic phase was washed with brine (50 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain crude product 5-3. LCMS (ESI) m/z: 1234.7 (M+1).

[0155] Step 3: Preparation of Compound 5

[0156] Trifluoroacetic acid (1.54 g, 13.51 mmol, 1 mL, 179.12 eq) was added to a solution of compound 5-3 (93 mg, 75.40 μmol, 1 eq) and anisole (16.31 mg, 150.80 μmol, 16.39 μL, 2 eq) in DCM (1 mL) at 0° C. The mixture was then stirred at 25° C. for 1 hour. The temperature was lowered to 0° C., n-heptane (6 mL*3) was added to the mixture, the supernatant was decanted, and it was pulped with cooled MTBE (4 mL) at 0° C., and then filtered under nitrogen protection. The crude product was purified by reverse phase HPLC (column: Shim-pack C18 150×25 mm×10 μm; mobile phase: [mobile phase A: water (0.1% TFA); mobile phase B: acetonitrile]; the percentage of mobile phase B: 12%-30%, 10 min) to obtain compound 5. LCMS (ESI) m/z: 625.0 (M+1).

Embodiment 6

Synthesis of Compound 6

[0157] ##STR00036##

[0158] Step 1: Preparation of Compound 6-2

[0159] A solution of acetic anhydride (17.93 mg, 175.62 μmol, 16.45 μL, 1 eq) in dichloromethane (0.5 mL) was added dropwise to a mixed solution of compound 4-10 (160 mg, 175.62 μmol, 1 eq), triethylamine (44.43 mg, 439.05 μmol, 61.11 μL, 2.5 eq) and DCM (5 mL) under nitrogen protection at 0° C., and stirred at this temperature for 1 hour. The solution was washed with brine (10 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The crude product 6-2 was obtained by purification with silica gel chromatography (PE/EA=2/1-0/1 to DCM/MeOH=10/1). LCMS (ESI) m/z: 953.5 (M+1).

[0160] Step 2: Preparation of Compound 6-3

[0161] Compound 6-2 (210 mg, 220.34 μmol, 1 eq) was dissolved in DMF (5 mL) under nitrogen protection at 25° C., and N,N-dimethylformamide sulfur trioxide complex (101.24 mg, 661.01 μmol, 3 eq) was added to the solution. It was stirred at this temperature for 1 hour. Water (10 mL) was added to the solution, and it was extracted with ethyl acetate (10 mL*3). The combined organic phase was washed with brine (20 mL*2), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain compound 6-3. LCMS: 1033.6 (M+1).

[0162] Step 3: Preparation of Compound 6

[0163] Anisole (99.43 mg, 919.51 μmol, 99.93 μL, 5 eq) and trifluoroacetic acid (20.97 mg, 183.90 μmol, 13.62 μL, 1 eq) were added to a solution of compound 6-3 (190 mg, 183.90 μmol, 1 eq) in DCM (0.8 mL) under nitrogen protection of at 0° C., and then the reaction solution was stirred at 25° C. for 1 hour. The temperature was lowered to 0° C., n-heptane (5 mL*2) was added to the mixture, the supernatant was decanted, it was pulped with cooled MTBE (10 mL) at 0° C., filtered, and the filter cake was washed with MTBE. The obtained crude product was purified by reverse phase HPLC (column: Waters Atlantis T3 150×30 mm×5 μm; mobile phase: [mobile phase A: water (0.1% TFA); mobile phase B: acetonitrile]; the percentage of mobile phase B: 5%-35%, 10 min) to obtain compound 6. .sup.1H NMR (400 MHz, DMSO-d.sub.6+D.sub.2O) δ=6.89 (s, 1H), 5.24 (d, J=5.6 Hz, 1H), 4.20-4.12 (m, 1H), 3.60 (quin, J=6.8 Hz, 1H), 3.53-3.36 (m, 2H), 3.15-2.99 (m, 3H), 2.91 (dd, J=7.0, 9.5 Hz, 1H), 1.87-1.73 (m, 3H), 1.38 (br s, 4H); LCMS: 625 (M+1); 545 (M-80+1).

Experimental Example 1: Detection of Antibacterial Activity (MIC) of the Compounds

[0164] Three strains of Klebsiella pneumonia, ATCC BAA-205 (TEM-1/SHV-1/SHV-12), ATCC BAA-1705 (KPC-2), ATCC BAA-2470 (NDM-1), Enterobacter cloacae ATCC BAA-1143 (AmpC), two strains of Escherichia coli ATCC BAA-2523 (OXA-48), ATCC 25922 were used to determine the minimum inhibitory concentration (MIC) of each of the compounds by micro-liquid dilution method according to the Institute of Clinical and Laboratory Standard (CLSI) requirements. A 2-fold serial dilution of the compound (final concentration ranging from 0.125 μg/ml to 128 g/ml) was added to a round-bottom 96-well plate (Catalog #3788, Corning), fresh monoclonal bacteria were selected from an overnight cultured Mueller Hinton II Agar medium plate (MHA, Cat. No. 211438, BD BBL™) and suspended in sterile normal saline, the concentration was adjusted to 1×10.sup.8 CFU/mL, and then the solution was diluted by using a cation-adjusted Hinton Mueller culture medium Cation-Adjusted Mueller Hinton II Broth (MHB, Catalog #212332, BD BBL™) to a concentration of 5×10.sup.5 CFU/ml, and 100 μl of the solution was added to a round bottom 96-well plate containing the drugs. The plate was placed upside down at 37° C. and the MIC value was read after 20-24 h of incubation, and the lowest drug concentration that inhibited the growth of bacteria was set as MIC. The results are shown in Table 1. Colony-Forming Units (CFU) refer to the total number of bacterial colonies per unit volume.

TABLE-US-00001 TABLE 1 Results of Antibacterial Activity Detection (MIC) of the Embodiments of the Present Disclosure Bacterial strain K. pneumonia E. cloacae E. coli E. coli ATCC ATCC ATCC ATCC ATCC ATCC BAA-205 BAA-1705 BAA-2470 BAA-1143 BAA-2523 25922 Drug resistant gene Class A Class A Class B Class C Class D Compound (TEM-1/SHV-1/SHV-12) (KPC-2) (NDM-1) (AmpC) (OXA-48) — Compound 1 0.5 0.5 0.5 1 0.5 1 Compound 2 1 2 1 2 1 4 Compound 3 2 2 1 2 0.25 4 Compound 4 0.5 1 0.25 0.5 0.125 0.25 Compound 5 1 1 0.5 1 0.25 0.5 Compound 6 2 8 1 1 0.25 4

[0165] Conclusion: The compound of the present disclosure has a good inhibition effect on various bacteria.

Experimental Example 2: Detection of Antibacterial Activity (MIC) of the Compounds on Clinically Isolated Bacteria

[0166] The minimum inhibitory concentration (MIC) of the compound and combination with β-lactamase (MBLs) inhibitors against clinically isolated carbapenem-resistant enterobacteriaceae was determined by the two-fold agar dilution method to determine the activity of the compound to be tested against strains producing MBLs. Antibiotics and enzyme inhibitors were weighed separately and dissolved in sterile ultrapure water or dimethyl sulfoxide to prepare mother liquor, MHA medium was prepared, pH was adjusted to 7.2-7.4, and it was sterilized at 121° C. for 15 minutes and placed in a 55° C. water bath for heat preservation. The mother liquor was diluted to the concentration to be tested by double dilution method, an inoculum liquid was prepared by direct bacterial suspension method, 1 mL of the prepared bacteria solution was withdrawn and putted into the inoculation tube, and a positioning needle and an inoculation needle were installed. A bacterial multi-point inoculator was started for inoculation. After the bacterial solution was absorbed by the agar, the plate was placed upside down in an incubator at 37° C. for 16-20 hours, and the results were observed. The average of three tests was taken. The test results of the single drug and combined drug of the compound are shown in Tables 2 and 3 below.

[0167] Conclusion: The antibacterial activity of the compound of the present disclosure and its combination with β-lactamase (MBLs) inhibitors is significantly better than that of LYS-228 and the marketed drugs meropenem and aztreonam.

TABLE-US-00002 TABLE 2 Minimum Inhibitory Concentration (μg/mL) and MIC.sub.50, MIC.sub.90 of the Compound of the Present Disclosure Strain name MIC and number Compound 4 LYS 228 Meropenem Aztreonam E.coli BAA-2452 0.125 0.5 16 16 E.coli 020028 0.03 0.125 16 16 E.coli 020031 0.5 4 32 4 E.coli 020033 1 8 32 32 E.coli 115101 0.5 4 128 >128 E.coli 115103 1 8 16 128 E.coli 115105 1 4 128 16 E.coli C1569 1 4 16 1 E.coli CRE18 1 4 32 >128 E.coli CRE21 1 4 64 >128 E.coli CRE23 1 2 32 >128 E.coli CRE28 1 4 32 >128 Morganella 0.125 0.25 2 4 morganii C1274 K.p BAA-2470 0.125 0.25 32 >128 K.p 11544 0.06 0.125 16 >128 K.p 13249 0.06 0.125 32 >128 K.p 115004 0.125 0.25 16 64 K.p C904 0.125 0.125 16 >128 K.p CRE11 0.125 0.125 32 128 K.p CRE12 0.06 0.125 16 4 K.p CRE16 0.06 0.06 8 64 K.p 090339 0.125 0.25 16 64 K.p HX30 0.5 2 128 >128 K.p HX37 0.25 0.5 32 >128 K.p HX77 0.03 0.03 16 16 K.p 6777 0.125 1 8 128 MIC.sub.50 0.125 0.5 16 128 MIC.sub.90 1 4 128 >128

TABLE-US-00003 TABLE 3 Minimum Inhibitory Concentration (μg/mL) and MIC.sub.50, MIC.sub.90 of the Compound of the Present Disclosure Combined with β-lactamase (MBLs) Inhibitor MIC Strain name Compound LYS228/ Aztreonam/ and number 4/Avibatan Avibatan Avibatan E.coli BAA-2452  0.06/2  0.25/2 0.125/2 E.coli 020028  0.03/2  0.25/2  0.06/2 E.coli 020031  0.5/2    4/2    2/2 E.coli 020033  0.5/2    4/2    8/2 E.coli 115101 0.125/2  0.25/2  0.5/2 E.coli 115103  0.5/2    4/2    4/2 E.coli 115105  0.5/2    4/2    2/2 E.coli C1569  0.5/2    4/2    1/2 E.coli CRE18  0.5/2    4/2    1/2 E.coli CRE21    1/2    8/2    2/2 E.coli CRE23  0.5/2    4/2    1/2 E.coli CRE28  0.5/2    4/2    1/2 Morganella 0.125/2  0.5/2 0.125/2 morganii C1274 K.p BAA-2470 0.125/2  0.5/2 0.125/2 K.p 11544  0.06/2 0.125/2 0.125/2 K.p 13249  0.06/2 0.125/2  0.06/2 K.p 115004 0.125/2  0.25/2 0.125/2 K.p C904 0.125/2  0.25/2 0.125/2 K.p CRE11 0.125/2  0.25/2  0.06/2 K.p CRE12  0.06/2 0.125/2  0.06/2 K.p CRE16  0.06/2  0.06/2  0.06/2 K.p 090339 0.125/2  0.25/2  0.06/2 K.p HX30  0.5/2    2/2    1/2 K.p HX37  0.25/2    1/2  0.5/2 K.p HX77 0.125/2  0.06/2  0.06/2 K.p 6777 0.125/2  0.5/2  0.5/2 MIC.sub.50 0.125/2  0.5/2 0.125/2 MIC.sub.90  0.5/2    4/2    2/2

Experimental Example 3: Experimental Evaluation of Drug Efficacy in Mice (Mouse Thigh Muscle Model)

[0168] 9 female CD-1 mice were divided into 3 cages, 3 mice per cage, and were injected intraperitoneally with immunosuppressant cyclophosphamide (150 mg/kg).

[0169] 24 hours later, 3 cages of mice were injected intraperitoneally again with immunosuppressant cyclophosphamide (100 mg/kg). The strain E. coli ATCC-25922 was recovered on an MHA plate. The recovered colonies were picked and dissolved in saline to prepare E. coli ATCC-25922 bacterial solution with a concentration of 1.36E+07 CFU/mL for use in mouse thigh muscle infection. The amount of bacterial solution injected into the thigh muscle of the experimental mice was 100 μL/mouse, that is, the inoculation amount was 1.36E+06 CFU/mouse. 2 h after infection, the thigh muscle tissue of the mice in control group was taken and placed in 10 mL saline, homogenized, and dotted on a plate with gradient dilution.

[0170] The specific administration of mice was as follows:

[0171] (1) 2 h after infection: At the end point of 2 h infection, the thigh muscle tissue of the mice in the first cage was taken and placed in 10 mL saline, homogenized, and dotted on a plate with gradient dilution, two duplications for each mouse. The amount of bacteria loaded in the thigh muscle tissue of the mouse was counted. Mice in the third cage were injected respectively with 100 mg/kg of compound 1 subcutaneously.

[0172] (2) 4, 6 and 8 h after infection: Mice in the third cage were injected respectively with 100 mg/kg of compound 1 subcutaneously. At the end point of 10 h infection, the thigh muscle tissue of the mice in the second to third cages was taken and placed in 10 mL saline, homogenized, and dotted on a plate with gradient dilution, two duplications for each mouse. The amount of bacteria loaded in the thigh muscle tissue of the mouse was counted, and the experimental results were sorted and shown in Table 4.

TABLE-US-00004 TABLE 4 Experimental Results of the Amount of Bacteria Loaded in Mouse Thigh Muscle Tissues Average CFU Group of the mouse 2 h control group 2.37E+06 10 h infection group 4.48E+08 Compound 1 (100 mg/kg) 2.25E+05

[0173] Conclusion: The compound of the present disclosure has a significant inhibitory effect on infection.

Experimental Example 4: Experimental Evaluation of Drug Efficacy in Mouse Thigh Muscle Infection Model

[0174] 15 female CD-1 mice were divided into 5 cages, 3 mice per cage; the day of infection was counted as day 0.

[0175] Immunosuppressant cyclophosphamide 150 mg/kg were injected intraperitoneally on Day-4, and immunosuppressant cyclophosphamide 100 mg/kg was injected intraperitoneally again on the first day to obtain immunodeficient mice.

[0176] The strain Klebsiella pneumoniae ATCC-BAA 2470 was recovered on an MHA plate on the first day. The recovered colonies were picked and dissolved in sterile saline to prepare bacterial solution with a concentration of 9.5E+07 CFU/mL for use in mouse thigh muscle infection. The infection starting time was counted as 0 h, and 100 μL of bacterial solution is injected into the thigh muscle of each mouse at 0 h, that is, the inoculation amount is 9.5E+06 CFU/mouse. 2 h after infection, the drugs were administered according to the experimental scheme. The specific experimental scheme is as follows (see Table 5):

[0177] (1) 2 h after infection: At the end point, the thigh muscle tissue of the mice in the first cage was taken and placed in 10 mL saline, the tissue was homogenized by a homogenizer, and the homogenate was dotted on a plate with gradient dilution, two duplications for each mouse.

[0178] (2) 2 h after infection: Mice in the second to third cages were administered separately at a volume of 10 mL/kg according to the mouse body weight. The mice in the second cage were administered with menstruum subcutaneously every 2 h to a 24 h end-point; the mice in the third cage were administered with compound 4 at 200 mg/kg by intraperitoneal injection every 2 h to a 24 h end-point. At the end point, the thigh muscle tissue was taken and placed in 10 mL sterile saline, the tissue was homogenized by a homogenizer, and the homogenate was dotted on a plate with gradient dilution, two duplications for each mouse. The amount of bacteria loaded in the thigh muscle tissue of the mouse was counted, and the experimental results were shown in Table 6.

TABLE-US-00005 TABLE 5 Experimental Scheme Experimental Number of Inoculation Administration Experimental group animals Compound dose mode end point 1 3 2 h control Klebsiella — 2 h  group Pneumoniae 2 3 24 h ATCC-BAA   5% DMSO + 24 h infection 2470 20% PEG400 + group 1.0E+07 saline CFU/mouse administered subcutaneously 3 3 Compound 200 mg/kg, 24 h 4 every 2 h, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 h, administered subcutaneously

TABLE-US-00006 TABLE 6 Experimental Results of the Amount of Bacteria Loaded in Mouse Thigh Muscle Tissue Average CFU Group of the mouse 2 h control group 4.53E+07 CFU/mouse 24 h infection group 2.10E+10 CFU/mouse Compound 4 (200 mg/kg) 3.93E+06 CFU/mouse

[0179] Conclusion: The compound of the present disclosure has a significant inhibitory effect on infection.