CN114957385B - Dipeptide compound containing beta-lactam ring, preparation method and application thereof - Google Patents

Abstract

The invention discloses a dipeptide compound containing a β-lactam ring, the general structural formula (I) of which is: The dipeptide compound containing a β-lactam ring of the present invention has good proteasome inhibitory activity, and also has strong in vitro proliferation inhibitory activity on multiple myeloma cells and acute leukemia cells such as RPMI-8226 and MV-4-11. . The synthetic raw materials of the compound of the present invention are easy to obtain, the route design is reasonable, the reaction conditions are mild, the yield of each step is high, the operation is simple, and it is suitable for industrial production.

Description

A type of dipeptide compound containing β-lactam ring, preparation method and application thereof

Technical Field

The present invention relates to the field of medicine, and in particular to a new type of dipeptide compound containing a β-lactam ring structure, a preparation method and application thereof, and application of the compound in the preparation of anti-tumor drugs.

Background Art

Malignant tumors have become one of the major public health issues that seriously threaten human health. According to the latest statistics from the Journal of Clinical Oncology, there will be approximately 19.3 million new cancer cases and nearly 10 million cancer deaths in 2020 (CA-Cancer. J. Clin. 2021, 71, 209-249). Over the past decade, the incidence and mortality of malignant tumors have been on the rise, and the research and development of anticancer drugs has become an important task in solving human health problems.

Proteasome is a giant protein complex in organisms, which plays an important role in degrading misfolded, unnecessary or damaged proteins in cells and maintaining protein homeostasis in cells. In addition to maintaining constant protein levels in the body, proteasome is also related to many life activities, including cell cycle regulation, cell apoptosis, gene transcription regulation, DNA repair and antigen presentation. For tumor cells, they mainly achieve cell growth by degrading some tumor suppressor factors and cell cycle checkpoint inhibitors through proteasomes, and have a certain dependence on proteasomes. Therefore, inhibiting the function of proteasomes can achieve the purpose of tumor treatment.

Currently, three short peptide proteasome inhibitors have been approved for marketing for the treatment of multiple myeloma. Several inhibitor molecules have entered clinical research, further proving the effectiveness of proteasomes as targets for tumor treatment. Most of these proteasome inhibitors are covalent binding inhibitors. However, with the emergence of covalent irreversible inhibitors, such as carfilzomib, there are many problems in clinical practice, such as large toxic side effects and limitations in the treatment of solid tumors. Covalent reversible proteasome inhibitors can not only ensure effective inhibitory activity, but also avoid the strong toxic side effects caused by irreversible binding. Therefore, covalent reversible proteasome inhibitors have great development potential in the research of new proteasome inhibitors in the future.

Summary of the invention

In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to design and synthesize a new class of short peptide proteasome inhibitors containing a β-lactam ring, and evaluate the proteasome inhibitory activity and tumor cell proliferation inhibitory activity of such compounds. The results show that such compounds have good proteasome inhibitory activity and cell proliferation inhibitory activity, and as a class of covalent reversible proteasome inhibitors with a new skeleton, they are expected to become an effective choice for clinical treatment of tumors.

Definition of terms:

The term "aryl" as used herein refers to an all-carbon monocyclic or condensed polycyclic group of 5 to 12 carbon atoms having a completely conjugated π electron system. Non-limiting examples of aromatic rings include benzene rings and naphthalene rings. The aromatic rings may be substituted or unsubstituted. The substituents of the aromatic rings are selected from halogen, nitro, C _1-4 alkyl, C _1-4 alkoxy.

The term "heterocyclic aryl" used in the present invention refers to an unsaturated carbon ring of 5-6 ring atoms, wherein one or more carbon atoms are replaced by heteroatoms such as oxygen, nitrogen, sulfur, etc. Specific heterocyclic aryl groups can be: pyridyl, pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl and isoxazolyl, etc.

The term "heterocyclic group" used in the present invention refers to a monocyclic group, which has 4-6 ring atoms, wherein at least one or two ring atoms are selected from nitrogen, oxygen, sulfur heteroatoms, and the remaining ring atoms are carbon atoms. Specific heterocyclic groups can be piperidinyl, piperazinyl, pyrrolidinyl, tetrahydropyranyl, oxetanyl, etc.

The term "alkoxy" used in the present invention refers to an -O-alkyl group. Specific alkoxy groups include methoxy, ethoxy, tert-butoxy, and the like.

The term "alkaryl" used in the present invention refers to an aryl group substituted by an alkyl group, the aryl group is preferably a phenyl group, and the alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, specifically methylphenyl, ethylphenyl, isopropylphenyl and the like.

The term "aralkyl" used in the present invention refers to an alkyl group substituted by an aryl group, the aryl group is preferably a phenyl group, and the alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, specifically benzyl, phenethyl, phenylisopropyl and the like.

The term "halogen" as used herein refers to fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine.

The purpose of the present invention is to provide a novel short peptide proteasome inhibitor compound containing a β-lactam ring, wherein the compound has the following general formula (I):

in:

_R1 is selected from aryl, heteroaryl, and these groups may be arbitrarily substituted by halogen, _C1-4 alkyl, or _C1-4 alkoxy;

R ₂ is selected from C _1-6 alkyl, alkaryl, C _1-6 alkyl-DR _a , wherein D is selected from O, S, CONH, and R _a is selected from H, C _1-6 alkyl;

_R3 is selected from H, _C1-6 alkyl, aryl, heteroaryl, aralkyl, heterocyclic group and _Rb -S(=O) _2- , wherein _Rb is selected from _C1-6 alkyl, halogenated _C1-4 alkyl and substituted aryl. These groups may be arbitrarily substituted by halogen, nitro, cyano, carbamoyl, N,N-dimethyl, halogenated _C1-4 alkyl, _C1-4 alkyl, _C1-4 alkoxy.

Preferably, R ₁ is selected from phenyl, pyridyl, pyrazinyl and thiazolyl, and the phenyl group may be substituted by a fluorine atom or a methoxy group;

R ₂ is selected from C _1-6 alkyl, alkaryl, C _1-6 alkyl-DR _a , wherein D is selected from S, CONH, and R _a is selected from H, C _1-6 alkyl; the C _1-6 alkyl is selected from methyl, ethyl, isopropyl, isobutyl, neopentyl, and the alkaryl is selected from methylphenyl and ethylphenyl;

_R3 is selected from H, _C1-6 alkyl, aryl, heteroaryl, aralkyl, heterocyclic group and _Rb -S(=O) _2- , wherein _Rb is selected from _C1-6 alkyl, halogenated _C1-4 alkyl and substituted aryl. The _C1-6 alkyl is selected from methyl and tert-butyl, the aryl is selected from benzene ring and naphthalene, the substituted substituent is selected from halogen, nitro, cyano, carbamoyl, N,N-dimethylamino, trifluoromethyl, methyl and methoxy, the heterocyclic aryl is selected from pyridyl, pyrimidyl, pyrazinyl, thiazolyl, oxazolyl and isoxazolyl, the aralkyl is selected from benzyl and phenethyl, the heterocyclic group is selected from tetrahydropyranyl and oxetanyl, and _Rb -S(=O) _2- is selected from methanesulfonyl, p-toluenesulfonyl, p-bromophenylsulfonyl, nitrobenzenesulfonyl, trifluoromethanesulfonyl and dansyl.

More specifically, the preferred compounds of the present invention having the general formula (I) are:

(S)-N ¹ -((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(pyrazine-2-carboxamide)succinamide

(S)-N ¹ -((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ¹ -((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(pyrazine-2-carboxamide)succinamide

(S)-N ¹ -((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ⁴ -neopentyl-2-nicotinamido-N ¹ -(S)-1-oxo-1-((S)-2-oxo-1-phenylazetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamido)-N ¹ -(S)-1-oxo-1-((R)-2-oxo-1-phenylazetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(p-tolyl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

(S)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ¹ -((S)-1-((R)-1-(4-(dimethylamino)phenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(4-(trifluoromethyl)phenyl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)pyrazine-2-carboxamide

N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)nicotinamide

N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)pyrazine-2-carboxamide

N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)nicotinamide

N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-3-methyl-1-oxobutan-2-yl)pyrazine-2-carboxamide

N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-3-methyl-1-oxobutan-2-yl)nicotinamide

N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxo-4-phenylbutan-2-yl)nicotinamide

N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxo-3-phenylpropan-2-yl)nicotinamide

N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-4-(methylthio)-1-oxobutan-2-yl)nicotinamide

(S)-2-Benzamido-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

(S)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(thiazole-2-carboxamide)succinamide

(S)-2-(4-Fluorobenzamido)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazepin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

(S)-2-(4-methoxybenzamide)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazepin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-4-methyl-1-oxopentan-2-yl)nicotinamide

(S)-N ¹ -((S)-1-((R)-1-(4-cyanophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ¹ -((S)-1-((R)-1-(4-(carbamoyl)phenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ¹ -((S)-1-((R)-1-(4-bromophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(pyrimidin-2-yl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(pyridin-3-yl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-((R)-1-(oxazol-2-yl)-2-oxazol-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(thiazol-2-yl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

(S)-N ¹ -((S)-1-((R)-1-(isoxazol-3-yl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ¹ -((S)-1-((R)-1-(methylsulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-p-tolylazetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

(S)-N ¹ -((S)-1-((R)-1-(tert-butyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ¹ -((S)-1-((R)-1-methyl-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamido)-N ¹ -(S)-1-((R)-1-(oxetan-3-yl)-2-oxetan-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)butanamide

(S)-N ⁴ -neopentyl-2-(nicotinamido)-N ¹ -(S)-1-oxo-1-((R)-2-oxo-1-(tetrahydropyran-4-yl)azetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide

(S)-N ¹ -((S)-1-((R)-1-((4-bromophenyl)sulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamido)-N ¹ -((S)-1-((R)-1-((4-nitrophenyl)sulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)succinamide

(S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-((trifluoromethyl)sulfonyl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

(S)-N ¹ -((S)-1-((R)-1-((8-(dimethylamino)naphthalen-2-yl)sulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamido)succinamide

Another object of the present invention is to provide a method for preparing the above-mentioned target compound, which is achieved by the following steps:

(1) Compound a and compound b react under the action of a condensing agent to obtain compound c. The selected condensing agents are (2-oxime-ethyl cyanoacetate)-N,N-dimethyl-morpholinourea hexafluorophosphate and 2,4,6-trimethylpyridine. The reaction temperature is 0°C-rt and the reaction time is three hours. The crude product can be directly used for the next reaction.

(2) Compound c undergoes self-cyclization and removal of the amino protecting group under the action of sulfonyldiimidazole and sodium hydride to generate compound d. The reaction temperature is -20-0°C and the reaction time is 2 hours. The crude product can be directly used for the next reaction.

(3) Compound d reacts with Boc-protected homophenylalanine in the presence of a condensing agent to obtain a condensation product, and then the amino protecting group is removed to obtain compound e. The condensing agent selected is 1-ethyl-3 (3-dimethylpropylamine) carbodiimide and 1-hydroxybenzotriazole, the reaction temperature is 0°C-rt, and the reaction time is 3 hours.

(4) Compound e is condensed with a Boc-protected amino acid and the amino protecting group is removed to obtain compound f. The condensing agent used is the same as that in step (3). The obtained crude product is separated by column chromatography to obtain a pure product.

(5) Compound f reacts with compound g in the presence of a condensation reagent to obtain compound I. The condensation reagent used is the same as that in step (3). The resulting crude product is separated by column chromatography to obtain a pure product.

Reaction:

Wherein: R ₁ is selected from aryl, heteroaryl, and the substituted substituent is selected from halogen, C _1-4 alkyl, C _1-4 alkoxy;

R ₂ is selected from C _1-6 alkyl, alkaryl, C _1-6 alkyl-DR _a , wherein D is selected from O, S, CONH, and R _a is selected from H, C _1-6 alkyl;

_R3 is selected from H, _C1-6 alkyl, aryl, heteroaryl, aralkyl, heterocyclic group and _Rb -S(=O) _2- , wherein _Rb is selected from _C1-6 alkyl, halogenated _C1-4 alkyl and substituted aryl. The _C1-6 alkyl is selected from methyl and tert-butyl, the aryl is selected from benzene ring and naphthalene, the substituted substituent is selected from halogen, nitro, cyano, carbamoyl, N,N-dimethylamino, trifluoromethyl, methyl and methoxy, the heterocyclic aryl is selected from pyridyl, pyrimidyl, pyrazinyl, thiazolyl, oxazolyl and isoxazolyl, the aralkyl is selected from benzyl and phenethyl, the heterocyclic group is selected from tetrahydropyranyl and oxetanyl, and _Rb -S(=O) _2- is selected from methanesulfonyl, p-toluenesulfonyl, p-bromophenylsulfonyl, nitrobenzenesulfonyl, trifluoromethanesulfonyl and dansyl.

Another object of the present invention is to provide a pharmaceutical composition comprising at least one compound in any form as described above, a stereoisomer or a pharmaceutically acceptable salt of the compound as an active ingredient, and one or more pharmaceutically acceptable carriers or excipients.

The pharmaceutical composition of the present invention can be prepared into various pharmaceutical dosage forms, such as oral administration, injection, inhalation, implantation, etc. Injection and oral administration are preferred, such as injection, lyophilized powder injection, tablet, capsule or granule.

The pharmaceutical composition of the present invention and various preparations of the composition can be prepared using conventional pharmaceutical carriers.

Another object of the present invention is to provide the pharmaceutical use of the compound of general formula (I) and the pharmaceutical composition containing the compound. That is, the present invention provides the use of the compound of general formula (I) and the pharmaceutical composition containing the compound in the preparation of drugs for treating malignant tumors or immune diseases.

Furthermore, the tumor is selected from myeloma, lymphoma, leukemia, breast cancer, sarcoma, lung cancer, macroglobulinemia, prostate cancer, kidney cancer, colon cancer, rectal cancer, pancreatic cancer, glioma, neuroblastoma, head cancer, neck cancer, liver cancer, thyroid cancer, ovarian cancer, cervical cancer, vulvar cancer, endometrial cancer, bladder cancer, testicular cancer, esophageal cancer, gastric cancer, cheek cancer, nasopharyngeal cancer, oral cancer, skin cancer, and gastrointestinal stromal tumor.

Experiments have shown that the dipeptide compound containing a β-lactam ring of the present invention has good proteasome inhibitory activity and has a good in vitro proliferation inhibitory effect on multiple myeloma cell line RPMI-8226 and acute leukemia cell line MV-4-11. The raw materials required for the synthesis of the compound of the present invention are easy to obtain, the route design is reasonable, the reaction conditions are mild, the yield of each step is high, the operation is simple, and it is suitable for industrial production.

DETAILED DESCRIPTION

The present invention is further described in conjunction with the examples. The following examples are only intended to illustrate the present invention, but are not intended to limit the present invention in any way.

Note: Ala: alanine; Val: valine; hPhe: homophenylalanine; Phe: phenylalanine; Met: methionine; Leu: leucine

Example 1 Preparation of (S)-3-amino-1-(4-fluorophenyl)azetidin-2-one

Cbz-L-serine (0.12 g, 0.5 mmol) was dissolved in 4.0 mL of DMF, and compound 1 (0.06 g, 0.5 mmol), TMP (0.07 g, 0.55 mmol) and COMU (0.24 g, 0.55 mmol) were added to the reaction system at 0°C, and the reaction was carried out at low temperature for 1 h, and then the temperature was raised to room temperature for 3 h. After the reaction was completed, the reaction solution was diluted with ethyl acetate (30.0 mL), extracted with 1 mol/L dilute hydrochloric acid (20.0 mL×3), and then extracted with saturated NaHCO ₃ aqueous solution (20.0 mL×3), the organic layer was collected and dried with anhydrous sodium sulfate, and then spin-dried to obtain 0.10 g of white solid 18. Yield: 65%; ¹ H NMR (500MHz, DMSO) δ 10.08 (s, 1H, NH), 7.65 (d, J = 9.0Hz, 2H, Ar-H), 7.37-7.34 (m, 6H, Ar-H+NH), 7.16-7.13 (m, 2H, Ar-H), 5.05 (s, 2H, CH ₂ ), 5.02-5. 00(m,1H,OH),4.22(dd,J＝13.6,6.4Hz,1H,CH),3.66-3.62(m,2H,CH ₂ ).

Compound 18 (0.04 g, 0.12 mmol) was dissolved in 3.0 mL of DMF, and placed in an ice bath. N,N-sulfonyldiimidazole (0.04 g, 0.18 mmol) was added to the reaction system at 0°C and stirred at low temperature for half an hour. Then the system temperature was lowered to -20°C, and NaH (0.18 mmol) was slowly added thereto and stirred for 1 hour. After the reaction was completed, 10.0 mL of a mixture of methanol and water (100:1) was added to the reaction solution, and solids precipitated. Then, the solids were filtered and dried to obtain a crude product 59. Yield: 87%; ¹ H NMR (400MHz, DMSO) δ8.11 (d, J = 8.4Hz, 1H, NH), 7.76-7.62 (m, 2H, Ar-H), 7.43-7.35 (m, 5H, Ar-H), 7.23 (t, J = 8.4Hz, 2H, Ar-H), 5.06 (s, 2H, CH ₂ ), 4.9 2-4.84(m,1H,CH),3.94(t,J＝5.6Hz,1H,CH ₂ ),3.59(dd,J＝5.2,2.8Hz,1H,CH ₂ ).

Compound 59 (0.60 g, 1.90 mmol) was placed in a two-necked bottle, and 0.06 g Pd/C and 10.0 mL anhydrous EtOH were added thereto. The hydrogen gas in the bottle was replaced, and the reaction was carried out at room temperature in a hydrogen atmosphere for 2 to 3 hours. After the reaction was completed, the reaction solution was filtered to remove Pd/C, and ethanol hydrochloric acid gas was added to the filtrate. A white solid was precipitated, and the crude product 82 was obtained by filtration. It did not need to be purified and was directly used in the next step.

Example 2 Preparation of (R)-3-amino-1-(p-tolyl)azetidinone

Synthesis of compound 19: Compound 2 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 19, yield: 73%; ¹ H NMR (500 MHz, DMSO) δ9.90 (s, 1H, NH), 7.50 (d, J = 8.0 Hz, 2H, Ar-H), 7.37 (d, J = 4.0 Hz, 3H, Ar-H), 7.34-7.18 (m, 3H, Ar-H + NH), 7.10 (d, J = 8.0 Hz, 2H, Ar-H), 5.04 (s, 2H, CH ₂ ), 4.97 (t, J = 5.5 Hz, 1H, CH), 4.25-4.19 (m, 1H, CH), 3.69-3.58 (m, 2H, CH ₂ ), 2.25 (s, 3H, CH ₃ ).

The synthesis and post-treatment of compound 60 were the same as those in Example 1, and white solid 60 was obtained. Yield: 87%; ¹ H NMR (500 MHz, DMSO) δ8.10 (d, J=8.5 Hz, 1H, NH), 7.41-7.29 (m, 5H, Ar-H), 7.25 (d, J=8.0 Hz, 2H, Ar-H), 7.18 (d, J=8.0 Hz, 2H, Ar-H), 5.06 (s, 2H, CH ₂ ), 4.90-4.84 (m, 1H, CH), 3.91 (t, J=6.0 Hz, 1H, CH ₂ ), 3.56 (dd, J=5.5, 3.0 Hz, 1H, CH ₂ ), 2.27 (s, 3H, CH ₃ ).

The synthesis and post-treatment of compound 83 were the same as in Example 1 to obtain white solid 17, which was directly used in the next reaction.

Example 3 Preparation of (R)-3-amino-1-(4-methoxyphenyl)azetidin-2-one

Synthesis of compound 20: Compound 3 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain a white solid 20, yield: 80%; ¹ H NMR (400 MHz, DMSO) δ9.85 (s, 1H, NH), 7.52 (d, J = 9.0 Hz, 2H, Ar-H), 7.41-7.19 (m, 6H, Ar-H + NH), 6.90-6.85 (m, 2H, Ar-H), 5.04 (s, 2H, CH ₂ ), 5.01-4.93 (m, 1H, OH), 4.20 (dd, J = 13.6, 6.0 Hz, 1H, CH), 3.71 (s, 3H, CH ₃ ), 3.69-3.56 (m, 2H, CH ₂ ).

The synthesis and post-treatment of compound 61 were the same as those in Example 1, and white solid 61 was obtained. Yield: 54%; ¹ H NMR (400 MHz, DMSO) δ8.10 (d, J=8.4 Hz, 1H, NH), 7.41-7.28 (m, 7H, Ar-H), 6.99-6.92 (m, 2H, Ar-H), 5.06 (s, 2H, CH ₂ ), 4.89-4.83 (m, 1H, CH), 3.90 (t, J=5.6 Hz, 1H, CH ₂ ), 3.73 (s, 3H, CH ₃ ), 3.55 (dd, J=5.6, 2.8 Hz, 1H, CH ₂ ).

The synthesis and post-treatment of compound 84 were the same as in Example 1 to obtain white solid 84, which was directly used in the next reaction.

Example 4 Preparation of (R)-3-amino-1-(4-(dimethylamino)phenyl)azetidin-2-one

Synthesis of compound 21: Compound 4 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 21, yield: 74%; ¹ H NMR (400 MHz, DMSO) δ9.69 (s, 1H, NH), 7.45-7.26 (m, 9H, Ar-H), 6.68 (d, J = 8.8 Hz, 1H, NH), 5.04 (s, 2H, CH ₂ ), 4.99-4.93 (m, 1H, OH), 4.19 (dd, J = 13.6, 6.4 Hz, 1H, CH), 3.69-3.57 (m, 2H, CH ₂ ), 2.84 (s, 6H, CH ₃ ).

The synthesis and post-treatment of compound 62 were the same as those in Example 1, and white solid 62 was obtained. Yield: 70%; ¹ H NMR (500 MHz, DMSO) δ8.09 (d, J = 8.5 Hz, 1H, NH), 7.41-7.34 (m, 5H, Ar-H), 7.22 (d, J = 9.0 Hz, 2H, Ar-H), 6.75 (d, J = 9.0 Hz, 2H, Ar-H), 5.06 (s, 2H, CH ₂ ), 4.88-4.82 (m, 1H, CH), 3.88 (t, J = 5.5 Hz, 1H, CH ₂ ), 3.51 (dd, J = 5.0, 2.5 Hz, 1H, CH ₂ ), 2.87 (s, 6H, CH ₃ ).

The synthesis and post-treatment of compound 85 were the same as in Example 1 to obtain white solid 85, which was directly used in the next reaction.

Example 5 Preparation of (R)-3-amino-1-(4-(trifluoromethyl)phenyl)azetidin-2-one

Synthesis of compound 22: Compound 5 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain a white solid 22, yield: 70%; ¹ H NMR (400 MHz, DMSO) δ10.41 (s, 1H, NH), 7.84 (d, J = 8.8 Hz, 2H, Ar-H), 7.69 (d, J = 8.4 Hz, 2H, Ar-H), 7.44 (d, J = 7.6 Hz, 1H, NH), 7.40-7.20 (m, 5H, Ar-H), 5.11-5.00 (m, 3H, CH ₂ +OH), 4.26 (dd, J = 13.5, 6.0 Hz, 1H, CH), 3.74-3.62 (m, 2H, CH ₂ ).

The synthesis and post-treatment of compound 63 were the same as those in Example 1, and white solid 63 was obtained. Yield: 70%; ¹ H NMR (400 MHz, DMSO) δ8.19 (d, J = 8.4 Hz, 1H, NH), 7.76 (d, J = 8.4 Hz, 2H, Ar-H), 7.53 (d, J = 8.4 Hz, 2H, Ar-H), 7.41-7.34 (m, 5H, Ar-H), 5.06 (s, 2H, CH ₂ ), 4.95-4.89 (m, 1H, CH), 4.01 (t, J = 6.0 Hz, 1H, CH ₂ ), 3.71-3.66 (m, 1H, CH ₂ ).

The synthesis and post-treatment of compound 86 were the same as in Example 1 to obtain white solid 86, which was directly used in the next reaction.

Example 6 Preparation of (R)-4-(3-amino-2-oxoazepine-1-yl)benzonitrile

Synthesis of compound 23: Compound 6 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain a white solid 23, with a yield of 68%; ESI-MS: m/z = 340.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 64 were the same as in Example 1, and a white solid 64 was obtained with a yield of 73%; ESI-MS: m/z = 322.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 87 were the same as in Example 1 to obtain white solid 87, which was directly used in the next reaction.

Example 7 Preparation of (R)-4-(3-amino-2-oxazepine-1-yl)-N-methylbenzamide

Synthesis of compound 24: Compound 7 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 24, yield: 65%; ESI-MS: m/z = 372.2 [M + H] ⁺ .

The synthesis and post-treatment of compound 65 were the same as in Example 1, and a white solid 65 was obtained with a yield of 70%; ESI-MS: m/z = 354.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 88 were the same as in Example 1 to obtain white solid 88, which was directly used in the next reaction.

Example 8 Preparation of (R)-3-amino-1-(4-bromophenyl)azetidin-2-one

Synthesis of compound 25: Compound 8 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 25, yield: 61%; ESI-MS: m/z = 393.0 [M + H] ⁺ .

The synthesis and post-treatment of compound 66 were the same as in Example 1, and white solid 66 was obtained. Yield: 76%; ESI-MS: m/z = 375.0 [M + H] ⁺ .

The synthesis and post-treatment of compound 89 were the same as in Example 1 to obtain white solid 89, which was directly used in the next reaction.

Example 9 Preparation of (R)-3-amino-1-(pyrimidin-2-yl)azacyclodextrin-2-one

Synthesis of compound 26: Compound 9 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 26, yield: 65%; ESI-MS: m/z = 317.1 [M + H] ⁺ .

The synthesis and post-treatment of compound 67 were the same as in Example 1, and white solid 67 was obtained. Yield: 72%; ESI-MS: m/z = 299.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 90 were the same as in Example 1 to obtain white solid 90, which was directly used in the next reaction.

Example 10 Preparation of (R)-3-amino-1-(pyridin-3-yl)azetidin-2-one

Synthesis of compound 27: Compound 10 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 27, yield: 60%; ESI-MS: m/z = 316.1 [M + H] ⁺ .

The synthesis and post-treatment of compound 68 were the same as in Example 1, and a white solid 68 was obtained with a yield of 75%; ESI-MS: m/z = 298.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 91 were the same as in Example 1 to obtain white solid 91, which was directly used in the next reaction.

Example 11 Preparation of (R)-3-amino-1-(oxazolyl-2-yl)azetidinone

Synthesis of compound 28: Compound 11 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain a white solid 28, with a yield of 53%; ESI-MS: m/z = 306.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 69 were the same as in Example 1, and a white solid 69 was obtained with a yield of 68%; ESI-MS: m/z = 288.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 92 were the same as in Example 1 to obtain white solid 92, which was directly used in the next reaction.

Example 12 Preparation of (R)-3-amino-1-(thiazol-2-yl)azetidin-2-one

Synthesis of compound 29: Compound 12 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 29, yield: 56%; ESI-MS: m/z = 322.1 [M + H] ⁺ .

The synthesis and post-treatment of compound 70 were the same as in Example 1, and a white solid 70 was obtained with a yield of 73%; ESI-MS: m/z = 304.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 93 were the same as in Example 1 to obtain white solid 93, which was directly used in the next reaction.

Example 13 Preparation of (R)-3-amino-1-(isoxazol-3-yl)azetidinone

Synthesis of compound 30: Compound 13 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 30, yield: 59%; ESI-MS: m/z = 306.1 [M + H] ⁺ .

The synthesis and post-treatment of compound 71 were the same as in Example 1, and white solid 71 was obtained. Yield: 76%; ESI-MS: m/z = 288.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 94 were the same as in Example 1 to obtain white solid 94, which was directly used in the next reaction.

Example 14 Preparation of benzyl (R)-(1-(methylsulfonyl)-2-oxoazepin-3-yl)carbamate

Synthesis of compound 31: Compound 61 was dissolved in a mixed solvent of acetonitrile and water, and then ammonium cerium nitrate was dissolved in water and added dropwise to the reaction system at low temperature. After the addition was complete, the reaction was carried out at 0°C for 15 minutes. After the reaction was completed, a saturated sodium bicarbonate aqueous solution was added to the reaction system to quench the reaction, and the reaction was extracted with ethyl acetate. A white solid 31 was obtained, with a yield of 56%; ESI-MS: m/z = 221.1 [M+H] ⁺ .

Synthesis of compound 72: Compound 31 was dissolved in acetonitrile, potassium carbonate was added, MsCl was added dropwise to the reaction system at low temperature, and then the reaction solution was heated to 60°C and heated for 5 hours to obtain white solid 72, yield: 49%; ESI-MS: m/z = 299.1 [M+H] ⁺ .

Synthesis of compound 95: Compound 72 was placed in a two-necked bottle, and Pd/C and anhydrous EtOH were added thereto. The hydrogen was replaced in the bottle, and the reaction was carried out at room temperature in a hydrogen atmosphere for 2 to 3 hours. After the reaction was completed, the reaction solution was filtered to remove Pd/C, and ethanol hydrochloric acid gas was added to the filtrate. A white solid was precipitated, and the crude product was filtered and used directly in the next step without purification.

Example 15 Preparation of (R)-3-amino-1-toluenesulfonylzebutan-2-one

Preparation of compound 73: Using compound and TsCl as raw materials, the synthesis and post-treatment methods were the same as those in Example 14 to obtain white solid 73, yield: 65%; ESI-MS: m/z = 375.1 [M+H] ⁺ .

Preparation of Compound 96: Compound 73 was used as the raw material. The synthesis and post-treatment methods were the same as those in Example 14. No purification was required and it was directly used in the next step.

Example 16 Preparation of (R)-3-amino-1-(tert-butyl)azetidin-2-one

Synthesis of compound 32: Compound 14 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 32, yield: 59%; ESI-MS: m/z = 295.2 [M + H] ⁺ .

The synthesis and post-treatment of compound 74 were the same as in Example 1, and white solid 74 was obtained. Yield: 67%; ESI-MS: m/z = 277.2 [M+H] ⁺ .

The synthesis and post-treatment of compound 97 were the same as in Example 1 to obtain white solid 97, which was directly used in the next reaction.

Example 17 Preparation of (R)-3-amino-1-methylazetidin-2-one

Synthesis of compound 33: Compound 15 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 33, yield: 54%; ESI-MS: m/z = 253.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 75 were the same as in Example 1, and white solid 75 was obtained. Yield: 63%; ESI-MS: m/z = 235.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 98 were the same as in Example 1 to obtain white solid 98, which was directly used in the next reaction.

Example 18 Preparation of (R)-3-amino-1-(oxetane-3-yl)azetidine-2-one

Synthesis of compound 34: Compound 16 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 34, yield: 58%; ESI-MS: m/z = 295.1 [M + H] ⁺ .

The synthesis and post-treatment of compound 76 were the same as in Example 1, and white solid 76 was obtained. Yield: 70%; ESI-MS: m/z = 277.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 99 were the same as in Example 1 to obtain white solid 99, which was directly used in the next reaction.

Example 19 Preparation of (3)-amino-1-(tetrahydropyran-4-yl)azetidin-2-one

Synthesis of compound 35: Compound 17 was used as the raw material, and the synthesis and post-treatment were the same as in Example 1 to obtain white solid 35, yield: 58%; ESI-MS: m/z = 295.1 [M + H] ⁺ .

The synthesis and post-treatment of compound 77 were the same as in Example 1, and white solid 77 was obtained. Yield: 70%; ESI-MS: m/z = 277.1 [M+H] ⁺ .

The synthesis and post-treatment of compound 100 were the same as in Example 1 to obtain white solid 100, which was directly used in the next reaction.

Example 20 Preparation of (R)-3-amino-1-((4-bromophenyl)sulfonyl)azetidin-2-one

Preparation of compound 78: Compound 31 and BsCl were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 14 to obtain white solid 78. Yield: 60%; ESI-MS: m/z = 439.0 [M+H] ⁺ .

Preparation of compound 101: Using 78 as starting material, the synthesis and post-treatment methods were the same as those of Example 14, and it was directly used in the next step without purification.

Example 21 (R)-3-amino-1-((4-nitrophenyl)sulfonyl)azetidin-2-one

Preparation of compound 79: Compound 31 and NsCl were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 14 to obtain a white solid. Yield: 69%; ESI-MS: m/z = 406.1 [M+H] ⁺ .

Preparation of compound 102: Using 79 as starting material, the synthesis and post-treatment methods were the same as those of Example 14, and it was directly used in the next step without purification.

Example 22 Preparation of (R)-3-amino-1-((trifluoromethyl)sulfonyl)azetidin-2-one

Preparation of compound 80: Compound 31 and TfCl were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 14 to obtain white solid 80. Yield: 65%; ESI-MS: m/z = 353.0 [M+H] ⁺ .

Preparation of Compound 103: Using Compound 80 as raw material, the synthesis and post-treatment methods were the same as those in Example 14, and it was directly used in the next step without purification.

Example 23 Preparation of (R)-3-amino-1-((8-(dimethylamino)naphthalen-2-yl)sulfonyl)azetidin-2-one

Preparation of compound 81: Compound 31 and dansyl chloride were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 14 to obtain a white solid. Yield: 51%; ESI-MS: m/z = 454.1 [M+H] ⁺ .

Preparation of Compound 104: Using Compound 81 as raw material, the synthesis and post-treatment methods were the same as those in Example 14, and it was directly used in the next step without purification.

Example 24 (S)-2-amino-N-((S)-1-(4-fluorophenyl)-2-oxazetidin-3-yl)-4-phenylbutylamine

Boc-protected homophenylalanine (0.28 g, 1.01 mmol) was dissolved in 5.0 mL of dichloromethane, HOBt (0.14 g, 1.01 mmol) and EDCI (0.29 g, 1.52 mmol) were added at 0°C, and the mixture was reacted at room temperature for half an hour. Compound 82 (0.20 g, 0.92 mmol) and DIPEA (0.47 mL, 2.76 mmol) were then added to the reaction system, and stirring was continued for three hours. After the reaction was completed, the reaction system was extracted with saturated aqueous NaHCO ₃ solution (20.0 mL), saturated aqueous NH ₄ Cl solution (20.0 mL) and saturated aqueous NaCl solution (20.0 mL) in sequence, and the organic layer was collected and dried with anhydrous sodium sulfate, and the solvent was removed by distillation under reduced pressure. The crude product was separated and purified by column chromatography (petroleum ether: ethyl acetate = 2:1) to obtain 0.30 g of white solid 108. Yield: 74%; ¹ HNMR (400MHz, CDCl ₃ ) δ7.35-7.27 (m, 3H, Ar-H), 7.25-7.17 (m, 3H, Ar-H+NH), 7.09-7.02 (m, 2H, Ar-H), 5.19 (d, J = 8.0Hz, 1H, NH), 5.11-5.04 (m, 1H, CH ),3.95(t,J＝5.6Hz,1H,CH ₂ ),3.60(dd,J＝5.6,2.4Hz,1H,CH ₂ ),2.78-2.66(m,1H,CH ₂ ),2.24-2.14(m,1H,CH ₂ ),2.02-1.90(m,1H,CH ₂ ),1.47(s,9H,CH ₃ ) .

Compound 108 (0.88 g, 2.0 mmol) was dissolved in 10.0 mL of dichloromethane, and 5.0 mL of trifluoroacetic acid was slowly added. The mixture was reacted at room temperature for 1 h. After the reaction, the solvent was dried to obtain a colorless oil 117, which was directly used in the next step.

Example 25 (S)-2-amino-N-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)-4-phenylbutanamide

Synthesis of compound 109: Compound 105 was used as the raw material for synthesis. The synthesis and post-treatment were the same as those in Example 24 to obtain white solid 109. The yield was 65%. ¹ H NMR (400 MHz, DMSO) δ8.68 (d, J=8.4 Hz, 1H, NH), 7.42-7.36 (m, 2H, Ar-H), 7.30-7.15 (m, 7H, Ar-H), 7.12 (d, J=8.0 Hz, 1H, NH), 5.05-4.99 (m, 1H, CH), 3.95-3.87 (m, 2H, CH+CH ₂ ), 3.55 (dd, J=5.6, 2.8 Hz, 1H, CH ₂ ), 2.69-2.53 (m, 2H, CH ₂ ), 1.94-1.73 (m, 2H, CH ₂ ),1.41(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 118 were the same as in Example 6 to obtain a colorless oil, which was directly used in the next reaction.

Example 26 (S)-2-amino-N-((S)-2-oxo-1-phenylazetidin-3-yl)-4-phenylbutylamine

Synthesis of compound 110: Compound 106 was used as the starting material for synthesis. The synthesis and post-treatment were the same as those in Example 24 to obtain white solid 110. The yield was 57%. ¹ H NMR (500 MHz, CDCl ₃ ) δ7.38–7.29 (m, 5H, Ar-H), 7.28–7.25 (m, 2H, Ar-H), 7.22–7.14 (m, 3H, Ar-H), 7.13–7.08 (m, 1H, NH), 5.25–5.23 (m, 1H, NH), 5.06–4.96 (m, 1H, CH), 4.15–4.07 (m, 1H, CH), 3.93–3.85 (m, 1H, CH ₂ ), 3.54 (dd, 1H, J=5.6, 2.8 Hz, 1H, CH ₂ ),2.68–2.53(m,2H,CH ₂ ),2.00–1.84(m,2H,CH ₂ ),1.43(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 119 were the same as in Example 6 to obtain a colorless oil, which was directly used in the next reaction.

Example 27 (S)-2-amino-N-((R)-2-oxo-1-phenylazetidin-3-yl)-4-phenylbutylamine

Synthesis of compound 111: Compound 107 was used as the synthetic raw material. The synthesis and post-treatment were the same as those in Example 24 to obtain white solid 111 with a yield of 55%. ¹ H NMR (500 MHz, DMSO) δ8.69 (d, J=8.2 Hz, 1H, NH), 7.40-7.33 (m, 4H, Ar-H), 7.28 (t, J=7.5 Hz, 2H, Ar-H), 7.19 (dd, J=7.7, 2.6 Hz, 3H, Ar-H), 7.13-7.08 (m, 2H, Ar-H+NH), 5.06-4.99 (m, 1H, CH), 3.97-3.87 (m, 2H, CH+CH ₂ ), 3.56 (dd, J=5.3, 2.8 Hz, 1H, CH ₂ ), 2.71-2.52 (m, 2H, CH ₂ ),1.95–1.71(m,2H,CH ₂ ),1.41(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 120 were the same as in Example 6 to obtain a colorless oil, which was directly used in the next reaction.

Example 28 Preparation of (S)-2-amino-N-((R)-2-oxo-1-(p-tolyl)azetidin-3-yl)-4-phenylbutylamine

Synthesis of compound 112: Compound 83 was used as the starting material for synthesis. The synthesis and post-treatment were the same as those in Example 24 to obtain white solid 112. The yield was 68%; ¹ H NMR (400 MHz, DMSO) δ8.70 (d, J=8.4 Hz, 1H, NH), 7.30-7.23 (m, 4H, Ar-H), 7.21-7.15 (m, 5H, Ar-H), 7.12 (d, J=8.0 Hz, 1H, NH), 5.06-4.99 (m, 1H, CH), 3.96-3.86 (m, 2H, CH+CH ₂ ), 3.52 (dd, J=5.2, 2.4 Hz, 1H, CH ₂ ), 2.69-2.53 (m, 2H, CH ₂ ), 2.27 (s, 3H, CH ₃ ), 1.96-1.74 (m, 2H, CH ₂ ),1.41(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 121 were the same as in Example 6 to obtain a colorless oil, which was directly used in the next reaction.

Example 29 Preparation of (S)-2-amino-N-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)-4-phenylbutanamide

Synthesis of compound 113: Compound 84 was used as the starting material for synthesis. The synthesis and post-treatment were the same as those in Example 24 to obtain white solid 113. The yield was 63%; ¹ H NMR (400 MHz, DMSO) δ8.68 (d, J=8.4 Hz, 1H, NH), 7.33-7.25 (m, 4H, Ar-H), 7.21-7.15 (m, 3H, Ar-H), 7.11 (d, J=7.6 Hz, 1H, NH), 6.98-6.92 (m, 2H, Ar-H), 5.05-4.98 (m, 1H, CH), 3.94-3.84 (m, 2H, CH+CH ₂ ), 3.73 (s, 3H, CH ₃ ), 3.50 (dd, J=5.2, 2.8 Hz, 1H, CH ₂ ), 2.69-2.53 (m, 2H, CH ₂ ),1.95-1.73(m,2H,CH ₂ ),1.41(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 122 were the same as in Example 6 to obtain a colorless oil, which was directly used in the next reaction.

Example 30 Preparation of (S)-2-amino-N-((R)-1-(4-(dimethylamino)phenyl)-2-oxoazetidin-3-yl)-4-phenylbutanamide

Synthesis of compound 114: Compound 85 was used as the raw material for synthesis. The synthesis and post-treatment were the same as those in Example 24 to obtain white solid 114. The yield was 70%. ¹ H NMR (500 MHz, DMSO) δ8.68 (d, J=8.0 Hz, 1H, NH), 7.27 (t, J=7.5 Hz, 2H, Ar-H), 7.24-7.15 (m, 5H, Ar-H), 7.09 (d, J=7.9 Hz, 1H, NH), 6.74 (d, J=9.0 Hz, 2H, Ar-H), 5.03-4.98 (m, 1H, CH), 3.95-3.89 (m, 1H, CH), 3.84 (t, J=5.5 Hz, 1H, CH ₂ ), 3.49-3.44 (m, 1H, CH ₂ ), 2.86 (s, 6H, CH ₃ ),2.68-2.52(m,2H,CH ₂ ),1.94-1.74(m,2H,CH ₂ ),1.41(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 123 were the same as in Example 6 to obtain a colorless oil, which was directly used in the next reaction.

Example 31 Preparation of (S)-2-amino-N-((R)-2-oxo-1-(4-(trifluoromethyl)phenyl)azetidin-3-yl)-4-phenylbutanamide

Synthesis of compound 115: Compound 86 was used as the starting material for synthesis. The synthesis and post-treatment were the same as those in Example 24 to obtain white solid 115. The yield was 59%. ¹ H NMR (400 MHz, DMSO) δ8.70 (d, J = 8.0 Hz, 1H, NH), 7.75 (d, J = 8.8 Hz, 2H, Ar-H), 7.53 (d, J = 8.4 Hz, 2H, Ar-H), 7.32-7.24 (m, 2H, Ar-H), 7.22-7.12 (m, 4H, Ar-H+NH), 5.09-5.01 (m, 1H, CH), 3.98 (t, J = 6.0 Hz, 1H, CH ₂ ), 3.95-3.88 (m, 1H, CH), 3.67-3.60 (m, 1H, CH ₂ ),2.69-2.53(m,2H,CH ₂ ),1.97-1.75(m,2H,CH ₂ ),1.41(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 124 were the same as in Example 6 to obtain a colorless oil, which was directly used in the next reaction.

Example 32 Preparation of N ⁴ -neopentyl- ^{N 2} -nicotinoyl-L-asparagine

Synthesis of compound 116: 3-pyridinecarboxylic acid was dissolved in dichloromethane, HOBt and EDCI were added at 0°C, and the reaction was carried out at room temperature for half an hour. BnO-Asp (4-pivalamide) and DIPEA were then added to the reaction system, and stirring was continued for three hours. After the reaction was completed, the reaction system was extracted with saturated NaHCO ₃ aqueous solution, saturated NH ₄ Cl aqueous solution and saturated NaCl aqueous solution in sequence, and the organic layer was collected and dried with anhydrous sodium sulfate, and the solvent was removed by distillation under reduced pressure. The crude product was separated and purified by column chromatography (dichloromethane: ethyl acetate = 3: 1) to obtain a white solid 116. Yield: 51%; ESI-MS: m/z = 398.2 [M+H] ⁺ .

Synthesis of compound 125: Compound 116 was dissolved in methanol and placed in a two-necked bottle, and a catalytic equivalent of Pd/C was added thereto. The mixture was reacted at room temperature for 5 hours under a hydrogen atmosphere. After the reaction was completed, the reaction system was filtered, the filtrate was dried by rotary evaporation, and used directly in the next step without purification.

Example 33 Preparation of (S)-2-amino-N ¹ -((S)-1-(((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

Boc-Asp (4-pivalamide) (0.30 g, 1.01 mmol) was dissolved in 2.0 mL of dichloromethane, HOBt (0.06 g, 0.44 mmol) and EDCI (0.29 g, 0.66 mmol) were added at 0°C, and the mixture was reacted at room temperature for half an hour. Compound 117 (0.20 g, 0.92 mmol) and DIPEA (0.13 mL, 2.76 mmol) were then added to the reaction system, and stirring was continued for three hours. After the reaction was completed, the reaction system was extracted with saturated aqueous NaHCO ₃ solution (10.0 mL), saturated aqueous NH ₄ Cl solution (10.0 mL) and saturated aqueous NaCl solution (10.0 mL) in sequence, and the organic layer was collected and dried with anhydrous sodium sulfate, and the solvent was removed by distillation under reduced pressure. The crude product was separated and purified by column chromatography (dichloromethane: ethyl acetate = 3:1) to obtain 0.16 g of white solid 126. Yield: 59%; ¹ HNMR (400MHz, DMSO) δ8.79 (d, J = 8.4Hz, 1H, NH), 8.24 (d, J = 8.0Hz, 1H, NH), 7.87 (t, J = 6.0Hz, 1H, NH), 7.43-7.35 (m, 2H, Ar-H), 7.32-7.23 (m, 4H, Ar-H), 7.23-7.15(m,3H,Ar-H),7.08(d,J＝8.0Hz,1H,NH),5.14-5.06(m,1H,CH),4.28(dd,J＝14.8,7.2Hz,1H,CH),4.23-4.15(m,1H,CH),3.96(t,J＝5.6Hz,1H,CH ₂ ),3.60(dd,J＝5.6,2.8Hz,1H,CH ₂ ),2.84(dd,J＝13.2,6.4Hz,1H,CH ₂ ),2.74(dd,J＝13.2,6.4Hz,1H,CH ₂ ),2.71-2.62(m,2H,CH ₂ ),2.62-2.54(m,2H,CH ₂ ),2 .13-2.04(m,1H,CH ₂ ),1.94-1.81(m,1H,CH ₂ ),1.39(s,9H,CH ₃ ),0.75(s,9H,CH ₃ ).

Compound 126 (1.02 g, 2.0 mmol) was dissolved in 10.0 mL of dichloromethane, and 5.0 mL of trifluoroacetic acid was slowly added. The mixture was reacted at room temperature for 1 h. After the reaction, the solvent was dried to obtain a colorless oil 142, which was directly used in the next step.

Example 34 Preparation of (S)-2-amino-N ¹ -((S)-1-(((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

The synthesis and post-treatment of compound 127 were the same as those of Example 33 to obtain white solid 46 in a yield of 53%; ¹ H NMR (400MHz, DMSO) δ8.80(d,J＝8.8Hz,1H,NH),8.27(d,J＝7.6Hz,1H,NH),7.88(t,J＝6.0Hz,1H,NH),7.41-7.34(m,2H,Ar-H),7.30-7.21(m,4H,Ar-H),7.20-7.14( m,3H,Ar-H),7.00(d,J＝7.6Hz,1H,NH),5.16-5.08(m,1H,CH),4.25(dd,J＝14.4,7.2Hz,1H,CH),4.16-4.09(m,1H,CH),3.92(t,J＝5.6Hz,1H,CH ₂ ),3.52(dd,J＝5.2,2.8Hz,1H,CH ₂ ),2.77(dd,J＝13.2,6.4Hz,1H,CH ₂ ),2.73-2.60(m,3H,CH ₂ ),2.59-2.52(m,2H,CH ₂ ),2.13-2.03(m,1H,CH ₂ ),1.93-1.7 8(m,1H,CH ₂ ),1.36(s,9H,CH ₃ ),0.70(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 60 were the same as in Example 33 to obtain a colorless oil, which was directly used in the next reaction.

Example 35 Preparation of (S)-2-amino-N ⁴ -neopentyl-N ¹ -((S)-1-oxo-1-((S)-2-oxo-1-phenylazetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

The synthesis and post-treatment of compound 128 were the same as those of Example 33 to obtain white solid 128, ¹ H NMR(500MHz,DMSO)δ8.80(d,J＝8.6Hz,1H,NH),8.27(d,J＝7.8Hz,1H,NH),7.88(t,J＝6.1Hz,1H,NH),7.38–7.32(m,4H,Ar-H),7.26(t,J＝7.5Hz,2H,Ar-H),7.20–7.1 4(m,3H,Ar-H),7.11–7.06(m,1H,Ar-H),7.01(d,J＝7.7Hz,1H,NH),5.15–5.07(m,1H,CH),4.25(dd,J＝14.3,7.3Hz,1H,CH),4.15–4.07(m,1H,CH),3.93(t,J ＝5.6Hz,1H,CH ₂ ),3.53(dd,J＝5.4,2.8Hz,1H,CH ₂ ),2.78(dd,J＝13.1,6.4Hz,1H,CH ₂ ),2.73–2.61(m,3H,CH ₂ ),2.60–2.52(m,2H,CH ₂ ),2.13–2.01(m,1H,CH ₂ ),1.90–1.8 0(m,1H,CH ₂ ),1.36(s,9H,CH ₃ ),0.70(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 144 were the same as in Example 33 to obtain a colorless oil which was directly used in the next reaction.

Example 36 (S)-2-amino-N ⁴ -neopentyl-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-benzoazetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

The synthesis and post-treatment of compound 129 were the same as those of Example 33 to obtain white solid 129. Yield: 64% ^. NMR (500MHz, DMSO) δ8.77(d,J＝8.4Hz,1H,NH),8.22(d,J＝8.1Hz,1H,NH),7.85(t,J＝6.1Hz,1H,NH),7.39–7.33(m,4H,Ar-H),7.26(t,J＝7.5Hz,2H,Ar-H),7.17(t,J＝ 5.6Hz,3H,Ar-H),7.09(ddd,J＝13.2,5.9,4.1Hz,2H,Ar-H+NH),5.10–5.04(m,1H,CH),4.26(q,J＝7.3Hz,1H,CH),4.21–4.13(m,1H,CH),3.94(t,J＝5.7Hz,1H,CH ₂ ),3.58(dd,J＝5.5,2.9Hz,1H,CH ₂ ),2.82(dd,J＝13.1,6.4Hz,1H,CH ₂ ),2.72(dd,J＝13.1,6.0Hz,1H,CH ₂ ),2.68–2.60(m,2H,CH ₂ ),2.59–2.52(m,2H,CH ₂ ),2 .12–2.01(m,1H,CH ₂ ),1.88–1.78(m,1H,CH ₂ ),1.37(s,9H,CH ₃ ),0.73(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 145 were the same as in Example 33 to obtain a colorless oil which was directly used in the next reaction.

Example 37 Preparation of 2-amino-N ⁴ -neopentyl-N ¹ -(S)-1-oxo-1-((S)-2-oxo-1-(p-tolyl)azetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide

The synthesis and post-treatment of compound 130 were the same as those of Example 33 to obtain white solid 130. Yield: 62%; ¹ H NMR (500MHz, DMSO) δ8.81(d,J＝8.5Hz,1H,NH),8.28(d,J＝8.0Hz,1H,NH),7.89(t,J＝6.0Hz,1H,NH),7.39-7.33(m,4H,Ar-H),7.27(t,J＝7.5Hz,2H,Ar-H),7.22-7.1 6(m,3H,Ar-H),7.12-7.08(m,1H,Ar-H),7.02(d,J＝7.5Hz,1H,NH),5.15-5.09(m,1H,CH),4.26(dd,J＝14.0,7.0Hz,1H,CH),4.17-4.10(m,1H,CH),3.94(t,J ＝5.5Hz,1H,CH ₂ ),3.54(dd,J＝5.0,2.5Hz,1H,CH ₂ ),2.79(dd,J＝13.5,6.5Hz,1H,CH ₂ ),2.74-2.62(m,3H,CH ₂ ),2.61-2.53(m,2H,CH ₂ ),2.27(s,3H,CH ₃ ),2.14-2.03(m,1 H,CH ₂ ),1.92-1.82(m,1H,CH ₂ ),1.37(s,9H,CH ₃ ),0.71(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 146 were the same as in Example 33 to obtain a colorless oil which was directly used in the next reaction.

Example 38 Preparation of (S)-2-amino-N ¹ -((S)-1-(((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

The synthesis and post-treatment of compound 131 were the same as those of Example 33 to obtain white solid 131 with a yield of 53%; ¹ H NMR(500MHz,DMSO)δ8.79(d,J＝8.5Hz,1H,NH),8.26(d,J＝7.5Hz,1H,NH),7.87(t,J＝6.0Hz,1H,NH),7.33-7.24(m,4H,Ar-H),7.22-7.15(m,3H),7.01(d,J＝7.5Hz,1H,NH),6.94(d,J＝9.0Hz,2H,Ar-H),5.13-5.08(m,1H,CH),4.26(dd,J＝14.0,7.0Hz,1H,CH),4.17-4.09(m,1H,CH),3.90(t,J＝5.5Hz,1H,CH ₂ ),3.73(s,3H,CH ₃ ),3.50(dd,J＝5.0,2.5Hz,1H,CH ₂ ),2.79(dd,J＝13.0,6.5Hz,1H,CH ₂ ),2.75-2.62(m,3H,CH ₂ ),2.60-2.53(m,2H,CH ₂ ),2.11-2.01(m,1H,CH ₂ ),1.93-1.7 6(m,1H,CH ₂ ),1.37(s,9H,CH ₃ ),0.72(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 147 were the same as in Example 33 to obtain a colorless oil, which was directly used in the next reaction.

Example 39 Preparation of 2-amino-N ¹ -(S)-1-((R)-1-(4-(dimethylamino)phenyl)-2-oxoazetidin-3-ylamino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

The synthesis and post-treatment of compound 132 were the same as those of Example 33 to obtain white solid 132. Yield: 65%; ¹ H NMR (400MHz, DMSO) δ8.77(d,J＝8.4Hz,1H,NH),8.25(d,J＝8.0Hz,1H,NH),7.86(t,J＝6.0Hz,1H,NH),7.29-7.23(m,2H,Ar-H),7.22-7.13(m,5H,Ar-H),7.01(d,J＝7 .6Hz,1H,NH),6.72(d,J＝8.8Hz,2H,Ar-H),5.10-5.04(m,1H,CH),4.25(dd,J＝14.4,7.2Hz,1H,CH),4.16-4.07(m,1H,CH),3.85(t,J＝5.6Hz,1H,CH ₂ ),3.45(dd,J＝4.8,2.4Hz,1H,CH ₂ ),3.35(s,6H,CH ₃ ),2.79(dd,J＝13.2,6.4Hz,1H,CH ₂ ),2.74-2.60(m,3H,CH ₂ ),2.60-2.53(m,2H,CH ₂ ),2.10-2.01(m,1 H,CH ₂ ),1.93-1.79(m,1H,CH ₂ ),1.36(s,9H,CH ₃ ),0.71(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 148 were the same as in Example 33 to obtain a colorless oil, which was directly used in the next reaction.

Example 40 Preparation of 2-amino-N ⁴ -neopentyl-N ¹ -(S)-1-oxo-1-((R)-2-oxo-1-(4-(trifluoromethyl)phenyl)azetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide

The synthesis and post-treatment of compound 133 were the same as those of Example 33 to obtain white solid 133. Yield: 55%; ¹ H NMR (400MHz, DMSO) δ8.85(d,J＝8.8Hz,1H,NH),8.32(d,J＝7.6Hz,1H,NH),7.91(t,J＝6.0Hz,1H,NH),7.73(d,J＝8.8Hz,2H,Ar-H),7.52(d,J＝8.8Hz,2H,Ar-H),7.31-7. 21(m,5H,Ar-H),7.06(d,J＝8.0Hz,1H,NH),5.21-5.14(m,1H,CH),4.48(dd,J＝13.6,7.2Hz,1H,CH),4.13-4.07(m,1H,CH),4.02-3.98(m,1H,CH ₂ ),3.55-3.47( m,1H,CH ₂ ),2.73(dd,J＝12.8,6.4Hz,1H,CH ₂ ),2.69-2.61(m,3H,CH ₂ ),2.60-2.55(m,2H,CH ₂ ),2.12-2.03(m,1H,CH ₂ ),1.89-1.82(m,1H,CH ₂ ),1.37(s,9H,CH ₃ ) ,0.66(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 149 were the same as in Example 33 to obtain a colorless oil, which was directly used in the next reaction.

Example 41 Preparation of (S)-2-((S)-2-aminopropionamido)-N-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)-4-phenylbutanamide

The synthesis and post-treatment of compound 134 were the same as those of Example 33 to obtain white solid 134 in a yield of 78%; ¹ H NMR (400 MHz, CDCl ₃ ) δ7.92 (d, J=6.8 Hz, 1H, NH), 7.32-7.22 (m, 4H, Ar-H), 7.21-7.12 (m, 3H, Ar-H+NH), 7.05-6.97 (m, 3H, Ar-H), 5.18-5.07 (m, 1H, NH), 5.01-4.90 (m, 1H, CH), 4.63-4.52 (m, 1H, CH), 4.17-4.06 (m, 1H, CH), 3.85 (t, J=5.4 Hz, 1H, CH ₂ ), 3.70-3.60 (m, 1H, CH ₂ ),2.75-2.58(m,2H,CH ₂ ),2.24-2.14(m,1H,CH ₂ ),2.08-1.95(m,1H,CH ₂ ),1.42(s,9H,CH ₃ ),1.28(d,J＝7.2Hz,3H,CH ₃ ).

The synthesis and post-treatment of compound 150 were the same as in Example 33 to obtain a colorless oil, which was directly used in the next reaction.

Example 42 Preparation of (S)-2-((S)-2-aminopropionamido)-N-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)-4-phenylbutanamide

The synthesis and post-treatment of compound 135 were the same as those of Example 33 to obtain white solid 135 in a yield of 73%; ¹ H NMR (400 MHz, DMSO) δ8.66 (d, J = 8.0 Hz, 1H, NH), 7.99 (d, J = 7.9 Hz, 1H, NH), 7.42-7.35 (m, 2H, Ar-H), 7.31-7.20 (m, 4H, Ar-H), 7.20-7.14 (m, 3H, Ar-H), 7.07 (d, J = 6.8 Hz, 1H, NH), 5.04-4.97 (m, 1H, CH), 4.27-4.19 (m, 1H, CH), 4.05-3.96 (m, 1H, CH), 3.92 (t, J = 5.6 Hz, 1H, CH ₂ ),3.56(dd,J＝5.2,2.8Hz,1H,CH ₂ ),2.69-2.52(m,2H,CH ₂ ),2.01-1.81(m,2H,CH ₂ ),1.35(s,9H,CH ₃ ),1.20(d,J＝7.2Hz,3H,CH ₃ ).

The synthesis and post-treatment of compound 151 were the same as in Example 33 to obtain a colorless oil, which was directly used in the next reaction.

Example 43 Preparation of (S)-2-amino-N-((S)-1-(((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-3-methylbutanamide

The synthesis and post-treatment of compound 136 were the same as those of Example 33 to obtain white solid 136, yield: 62%; ¹ H NMR (400 MHz, DMSO) δ8.70 (d, J = 7.6 Hz, 1H, NH), 8.00 (d, J = 8.0 Hz, 1H, NH), 7.43-7.35 (m, 2H, Ar-H), 7.30-7.22 (m, 4H, Ar-H), 7.21-7.15 (m, 3H, Ar-H), 6.84 (d, J = 8.4 Hz, 1H, NH), 5.08-5.00 (m, 1H, CH), 4.35-4.20 (m, 2H, CH), 3.96-3.91 (m, 1H, CH ₂ ), 3.85-3.79 (m, 1H, CH ₂ ),2.65-2.56(m,1H,CH),2.03-1.81(m,4H,CH ₂ ),1.38(s,9H,CH ₃ ),0.87(d,J＝6.8Hz,3H,CH ₃ ),0.84(d,J＝6.8Hz,3H,CH ₃ ).

The synthesis and post-treatment of compound 152 were the same as in Example 33 to obtain a colorless oil which was directly used in the next reaction.

Example 44 Preparation of (S)-2-amino-N-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazepin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-4-phenylbutylamine

The synthesis and post-treatment of compound 137 were the same as those of Example 33 to obtain white solid 137 in a yield of 65%. ¹ H NMR (500 MHz, DMSO) δ8.70 (d, J=8.0 Hz, 1H, NH), 8.06 (d, J=7.8 Hz, 1H, NH), 7.40-7.33 (m, 2H, Ar-H), 7.28-7.22 (m, 6H, Ar-H), 7.21-7.15 (m, 7H, Ar-H+NH), 5.03-4.95 (m, 1H, CH), 4.25 (dd, J=12.7, 8.5 Hz, 1H, CH), 3.98 (dd, J=13.2, 7.9 Hz, 1H, CH), 3.91 (t, J=5.6 Hz, 1H, CH ₂ ),3.54(dd,J＝5.4,2.7Hz,1H,CH ₂ ),2.68–2.53(m,4H,CH ₂ ),1.98–1.80(m,4H,CH ₂ ),1.38(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 153 were the same as in Example 33 to obtain a colorless oil which was directly used in the next reaction.

Example 45 Preparation of (S)-2-((S)-2-amino-3-phenylpropanamide)-N-((S)-1-(4-fluorophenyl)-2-oxazetidine-3-yl)-4-phenylbutylamine

The synthesis and post-treatment of compound 138 were the same as those of Example 33 to give a white solid 138 in a yield of 69%. ¹ H NMR (500 MHz, DMSO) δ8.67 (d, J=8.1 Hz, 1H, NH), 8.14 (d, J=7.9 Hz, 1H, NH), 7.42-7.37 (m, 2H, Ar-H), 7.28-7.23 (m, 7H, Ar-H), 7.22-7.16 (m, 5H, Ar-H), 7.02 (d, J=8.4 Hz, 1H, NH), 5.03-4.98 (m, 1H, CH), 4.30-4.20 (m, 2H, CH), 3.93 (t, J=5.6 Hz, 1H, CH ₂ ), 3.56 (dd, J=5.4, 2.7 Hz, 1H, CH ₂ ),3.02(dd,J＝13.8,4.0Hz,1H,CH ₂ ),2.77(dd,J＝13.8,10.5Hz,1H,CH ₂ ),2.67–2.55(m,2H,CH ₂ ),2.00–1.83(m,2H,CH ₂ ),1.30(s,9H,CH ₃ ).

The synthesis and post-treatment of compound 154 were the same as in Example 33 to obtain a colorless oil which was directly used in the next reaction.

Example 46 Preparation of (S)-2-amino-N-((S)-1-(((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-4-(methylthio)butanamide

The synthesis and post-treatment of compound 139 were the same as those of Example 33 to obtain white solid 139, yield: 63%; ¹ H NMR (500 MHz, DMSO) δ8.63 (d, J = 8.0 Hz, 1H, NH), 8.22 (d, J = 8.0 Hz, 1H, NH), 7.40-7.35 (m, 2H, Ar-H), 7.30-7.19 (m, 5H, Ar-H), 7.18-7.14 (m, 3H, Ar-H), 7.12 (d, J = 7.0 Hz, 1H, NH), 5.06-5.00 (m, 1H, CH), 4.28-4.21 (m, 1H, CH), 4.07-4.00 (m, 1H, CH), 3.95 (t, J = 5.5 Hz, 1H, CH ₂ , 1.33 _{( s} , _9H , _{CH 3 ) .}

The synthesis and post-treatment of compound 155 were the same as in Example 33 to obtain a colorless oil which was directly used in the next reaction.

Example 47 Preparation of (S)-2-amino-N-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazepin-3-yl)amino)-1-oxo-4-phenylbutane-2-yl)-4-methylpentamide

Synthesis of compound 140: Compound 118 and Boc-protected leucine were used as raw materials. The synthesis and post-treatment were the same as in Example 33 to obtain white solid 140. The yield was 60%. ESI-MS: m/z = 555.3 [M+H] ⁺ .

The synthesis and post-treatment of compound 156 were the same as in Example 33 to obtain a colorless oil, which was directly used in the next reaction.

Example 48 Preparation of (S)-2-((S)-4-(neopentylamino)-2-(nicotinamido)-4-oxobutylamino)-4-phenylbutyric acid

Compound 141 and synthesis: Compound 125 and homophenylalanine benzyl ester were used as raw materials, and the synthesis and post-treatment were the same as in Example 33 to obtain white solid 141, yield: 49%, ESI-MS: m/z = 559.3 [M + H] ⁺ .

The synthesis and post-treatment of compound 157 were the same as in Example 33 to obtain a colorless oil, which was directly used in the next reaction.

Example 49 Preparation of (S)-N ¹ -((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(pyrazine-2-carboxamide)succinamide

2-Pyrazinecarboxylic acid (0.04 g, 0.33 mmol) was dissolved in 2.0 mL of dichloromethane, HOBt (0.05 g, 0.33 mmol) and EDCI (0.10 g, 0.50 mmol) were added at 0°C, and the mixture was reacted at room temperature for half an hour. Compound 142 (0.20 g, 0.30 mmol) and DIPEA (0.18 mL, 0.90 mmol) were then added to the reaction system, and stirring was continued for three hours. After the reaction was completed, the reaction system was extracted with saturated aqueous NaHCO ₃ solution (10.0 mL), saturated aqueous NH ₄ Cl solution (10.0 mL) and saturated aqueous NaCl solution (10.0 mL) in sequence, and the organic layer was collected and dried with anhydrous sodium sulfate, and the solvent was removed by distillation under reduced pressure. The crude product was separated and purified by column chromatography (dichloromethane: ethyl acetate = 1:1) to obtain 0.15 g of white solid 158. Yield: 61%; ¹ H NMR (400MHz, DMSO) δ9.23(s,1H,pyrazine-H),8.98(d,J＝7.6Hz,1H,NH),8.93(d,J＝7.2Hz,1H,pyrazine-H),8.85(d,J＝8.0Hz,1H,NH),8.79(d,J＝8.0Hz,1H,pyrazine-H),8.4 4(d,J＝7.6Hz,1H,NH ),8.02(t,J＝5.2Hz,1H,NH),7.40-7.37(m,2H,Ar-H),7.32-7.21(m,4H,Ar-H),7.19-7.15(m,3H,Ar-H),5.15-5.06(m,1H,CH),4.92-4.82(m,1H,CH),4.30 -4.19(m,1H,CH),3.96(t,J＝4.8Hz,1H,CH ₂ ),3.65-3.54(m,1H,CH ₂ ),2.93(dd,J＝14.4,5.6Hz,1H,CH ₂ ),2.87-2.74(m,3H,CH ₂ ),2.72-2.56(m,2H,CH ₂ ),2.18-2.05(m,1H,CH ₂ ),1.96-1.81(m, 1H,CH ₂ ), 0.69 (s, 9H, CH ₃ ); ESI-MS: m/z=632.3[M+H] ⁺ .

Example 50 Preparation of (S)-N ¹ -((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 159: 3-pyridinecarboxylic acid and compound 142 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 159. The yield was 78%; ¹ H NMR (500 MHz, DMSO) δ9.08-9.02 (m, 2H, pyridine-H+NH), 8.84 (d, J＝8.5 Hz, 1H, NH), 8.71 (dd, J＝5.0, 1.5 Hz, 1H, pyridine-H), 8.45 (d, J＝8.0 Hz, 1H, NH), 8.28-8.23 (m, 1H, pyridine-H), 8.05 (t, J＝6.5 Hz, 1H, NH), 7 .50(dd,J＝7.5,5.0Hz,1H,pyridine-H),7.42-7.36(m,2H,Ar-H),7.26-7.20(m,4H,Ar-H),7.19-7.13(m,3H,Ar-H),5.11-5.05(m,1H,CH),4.83(q,J＝7.5Hz,1H ,CH),4.26-4.15(m,1H,CH),3.95(t,J＝6.0Hz,1H,CH ₂ ),3.60(dd,J＝5.0,2.5Hz,1H,CH ₂ ),2.90-2.84(m,1H,CH ₂ ),2.84-2.78(m,2H,CH ₂ ),2.78-2.73(m,1H,CH ₂ ),2.69-2.62(m,1H,CH ₂ ),2.60-2.53(m,1 H,CH ₂ ), 2.11-2.02 (m, 1H, CH ₂ ), 1.93-1.83 (m, 1H, CH ₂ ), 0.73 (s, 9H, CH ₃ ); ESI-MS: m/z=631.3[M+H] ⁺ .

Example 51 Preparation of (S)-N ¹ -((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(pyrazine-2-carboxamide)succinamide

Synthesis of compound 160: 2-pyrazinecarboxylic acid and compound 143 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 160. The yield was 80%; ¹ H NMR (500 MHz, DMSO) δ9.20 (d, J = 1.0 Hz, 1H, pyrazine-H), 8.94-8.87 (m, 3H, pyrazine-H + NH), 8.76 (dd, J = 2.5, 1.5 Hz, 1H, pyrazine-H), 8.46 (d, J = 7.5 Hz, 1H, NH), 8.03 (t, J = 6.0 Hz ,1H,NH),7.41-7.36(m,2H,Ar-H),7.27-7.19(m,4H,Ar-H),7.19-7.14(m,3H,Ar-H),5.18-5.13(m,1H,CH),4.87-4.80(m,1H,CH),4.21-4.15(m,1H,CH), 3.95(t,J＝5.5Hz,1H,CH ₂ ),3.55(dd,J＝5.0,2.5Hz,1H,CH ₂ ),2.94(dd,J＝15.0,6.0Hz,1H,CH ₂ ),2.85(dd,J＝14.5,5.5Hz,1H,CH ₂ ),2.74-2.66(m,2H,CH ₂ ),2.65-2.54(m,2H,CH ₂ ) ,2.15-2.07(m,1H,CH ₂ ),1.92-1.82(m,1H,CH ₂ ),0.60(s,9H,CH ₃ ); ESI-MS: m/z＝632.3[M+H] ⁺ .

Example 52 Preparation of (S)-N ¹ -((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 161: 3-pyridinecarboxylic acid and compound 143 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 161. The yield was 75%. ¹ H NMR (500 MHz, DMSO) δ9.02 (d, J = 1.5 Hz, 1H, pyridine-H), 8.90 (d, J = 7.5 Hz, 1H, NH), 8.79 (d, J = 8.5 Hz, 1H, NH), 8.71 (dd, J = 4.5, 1.5 Hz, 1H, pyridine-H), 8.46 (d, J = 7.5 Hz, 1H, NH), 8.23-8.15 (m, 1H, pyridine-H), 7.92 (t, J = 6.5 Hz, 1H, N H),7.53-7.47(m,1H,pyridine-H),7.39-7.33(m,4H,Ar-H),7.26-7.20(m,2H,Ar-H),7.18-7.13(m,3H,Ar-H),7.12-7.07(m,1H,Ar-H),5.14-5.10(m,1H,CH), 4.82(q,J＝7.0Hz,1H,CH),4.19-4.12(m,1H,CH),3.94(t,J＝6.0Hz,1H,CH ₂ ),3.55(dd,J＝5.5,3.0Hz,1H,CH ₂ ),2.87-2.81(m,2H,CH ₂ ),2.75-2.69(m,2H,CH ₂ ),2.69-2.64(m,1H,CH ₂ ),2.60-2.54(m,1H,CH ₂ ),2.13-2.03(m,1 H,CH ₂ ), 1.93-1.83 (m, 1H, CH ₂ ), 0.70 (s, 9H, CH ₃ ); ESI-MS: m/z=631.3[M+H] ⁺ .

Example 53 Preparation of (S)-N ⁴ -neopentyl-2-nicotinamido-N ¹ -(S)-1-oxo-1-((S)-2-oxo-1-phenylazetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 162: 3-pyridinecarboxylic acid and compound 144 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 162. The yield was 59%. ¹ H NMR (500 MHz, DMSO) δ9.02 (d, J = 1.6 Hz, 1H, pyridine-H), 8.90 (d, J = 7.6 Hz, 1H, NH), 8.80 (d, J = 8.6 Hz, 1H, NH), 8.71 (dd, J = 4.8, 1.6 Hz, 1H, pyridine-H), 8.47 (d, J = 7.8 Hz, 1H, NH), 8.24-8.14 (m, 1H, pyridine-H), 7.92 (t, J = 6.2 Hz, 1H, NH), 7.55-7.47 (m, 1H, pyridi ne-H),7.39–7.34(m,4H,Ar-H),7.26–7.20(m,2H,Ar-H),7.16(dd,J＝6.8,4.3Hz,3H,Ar-H),7.10(ddd,J＝8.5,6.4,2.2Hz,1H,Ar-H),5.12(ddd,J＝8.6,5.8,2. 8Hz,1H,CH),4.82(q,J＝7.2Hz,1H,CH),4.16(ddd,J＝11.6,7.9,4.0Hz,1H,CH),3.95(t,J＝5.6Hz,1H,CH ₂ ),3.56(dd,J＝5.5,2.8Hz,1H,CH ₂ ),2.84(ddd,J＝10.9,6.7,3.2Hz,2H,CH ₂ ),2.76–2.62(m,3H,CH ₂ ),2.56(dt,J＝11.3,7.2Hz,1H,CH ₂ ),2.13–1.83(m,2 H,CH ₂ ), 0.70 (s, 9H, CH ₃ ); ESI-MS: m/z=613.3[M+H] ⁺ .

Example 54 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamido)-N ¹ -(S)-1-oxo-1-((R)-2-oxo-1-phenylazetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 163: Using 3-pyridinecarboxylic acid and compound 145 as raw materials, the synthesis and post-treatment were the same as in Example 49 to obtain white solid 163, yield: 64%, ¹ H NMR (500 MHz, DMSO) δ9.03 (d, J = 1.6 Hz, 1H, pyridine-H), 8.96 (d, J = 7.6 Hz, 1H, NH), 8.78 (d, J = 8.4 Hz, 1H, NH), 8.71 (dd, J = 4.8, 1.6 Hz, 1H, pyridine-H), 8.43 (d, J = 8.0 Hz, 1H, NH), 8.24-8.19 (m, 1H, pyridine-H), 7.93 (t, J = 6.2 Hz, 1H, NH), 7.89 (d, J = 7.9 Hz, 1H, NH), 8.90 (d, J = 8.0 Hz, 1H, NH), 7.5 .51(dd,J＝7.9,4.8Hz,1H,pyridine-H),7.40–7.32(m,4H,Ar-H),7.26–7.21(m,2H,Ar-H),7.19–7.13(m,3H,Ar-H),7.12–7.08(m,1H,Ar-H),5.12–5.07(m,1H ,CH),4.83(q,J＝7.3Hz,1H,CH),4.25–4.15(m,1H,CH),3.95(t,J＝5.7Hz,1H,CH ₂ ),3.60(dd,J＝5.5,2.9Hz,1H,CH ₂ ),2.89–2.80(m,2H,CH ₂ ),2.78–2.70(m,2H,CH ₂ ),2.69–2.62(m,1H,CH ₂ ),2.59–2.52(m,1H,CH ₂ ),2.13–2.03(m,1 H,CH ₂ ), 1.92–1.82 (m, 1H, CH ₂ ), 0.73 (s, 9H, CH ₃ ); ESI-MS: m/z＝613.3[M+H] ⁺ .

Example 55 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(p-tolyl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 164: 3-pyridinecarboxylic acid and compound 146 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 164. The yield was 56%. ¹ H NMR (500 MHz, DMSO) δ9.02 (d, J = 1.5 Hz, 1H, pyridine-H), 8.91 (d, J = 8.0 Hz, 1H, NH), 8.78 (d, J = 8.5 Hz, 1H, NH), 8.71 (dd, J = 5.0, 1.5 Hz, 1H, pyridine-H), 8.46 (d, J = 8.0 Hz, 1H,, NH), 8.22-8.16 (m, 1H, pyridine-H), 7. .91(t,J＝6.0Hz,1H,NH),7.50(dd,J＝7.5,4.5Hz,1H,pyridine-H),7.26-7.20(m,4H,Ar-H),7.19-7.10(m,5H,Ar-H),5.13-5.07(m,1H,CH),4.82(q,J＝7.0Hz,1H ,CH),4.19-4.13(m,1H,CH),3.91(t,J＝5.5Hz,1H,CH ₂ ),3.52(dd,J＝5.5,3.0Hz,1H,CH ₂ ),2.87-2.80(m,2H,CH ₂ ),2.76-2.69(m,2H,CH ₂ ),2.69-2.63(m,1H,CH ₂ ),2.60-2.53(m,1H,CH ₂ ),2.26(s,3H,CH ₃ ), 2.12-2.03(m,1H,CH ₂ ), 1.92-1.83(m,1H,CH ₂ ), 0.71(s,9H,CH ₃ ); ESI-MS: m/z＝627.3[M+H] ⁺ .

Example 56 Preparation of (S)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 165: 3-pyridinecarboxylic acid and compound 147 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 165. The yield was 56%. ¹ H NMR (500 MHz, DMSO) δ9.03 (d, J = 2.0 Hz, 1H, pyridine-H), 8.92 (d, J = 7.5 Hz, 1H, NH), 8.78 (d, J = 8.5 Hz, 1H, NH), 8.71 (dd, J = 5.0, 1.5 Hz, 1H, pyridine-H), 8.47 (d, J = 8.0 Hz, 1H, NH), 8.25-8.16 (m, 1H, pyridine-H), 7.92 (t, J = 6.0 Hz, 1H, NH), 7.70 (d, J = 7.0 Hz, 1H, NH), 7.91 (d, J = 6.0 Hz, 1H, NH), 7.69 (d, J = 7.5 Hz, 1H, NH), 7.50 (d, J = 7.5 Hz, 1H, NH), 7.62 (d, J = 7.5 Hz, 1H, NH .51(dd,J＝7.5,5.0Hz,1H,pyridine-H),7.34-7.28(m,2H,Ar-H),7.27-7.20(m,2H,Ar-H),7.19-7.13(m,3H,Ar-H),6.98-6.91(m,2H,Ar-H),5.14-5.08(m,1H ,CH),4.83(q,J＝7.0Hz,1H,CH),4.19-4.13(m,1H,CH),3.91(t,J＝5.5Hz,1H,CH ₂ ),3.72(s,3H,CH ₃ ),3.51(dd,J＝5.5,2.5Hz,1H,CH ₂ ),2.89-2.80(m,2H,CH ₂ ),2.76-2.64(m,3H,CH ₂ ),2.60-2.52(m,1H,CH ₂ ),2.14-2.03(m,1H,CH ₂ ), 1.93-1.82 (m, 1H, CH ₂ ), 0.71 (s, 9H, CH ₃ ); ESI-MS: m/z=643.3[M+H] ⁺ .

Example 57 Preparation of (S)-N ¹ -((S)-1-((R)-1-(4-(dimethylamino)phenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 166: 3-pyridinecarboxylic acid and compound 148 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 166. The yield was 53%; ¹ H NMR (500 MHz, DMSO) δ9.03 (d, J = 1.5 Hz, 1H, pyridine-H), 8.93 (d, J = 8.0 Hz, 1H, NH), 8.77 (d, J = 8.5 Hz, 1H, NH), 8.73 (dd, J = 4.5, 1.0 Hz, 1H, pyridine-H), 8.45 (d, J = 7.5 Hz, 1H, NH), 8.26-8.20 (m, 1H, pyridine-H), 7.91 ( t,J＝6.0Hz,1H,NH),7.54(dd,J＝8.0,5.0Hz,1H,pyridine-H),7.28-7.20(m,5H,Ar-H),7.19-7.12(m,4H,Ar-H),5.10-5.06(m,1H,CH),4.82(dd,J＝14.0,7.0Hz,1H ,CH),4.18-4.13(m,1H,CH),3.88(t,J＝5.5Hz,1H,CH ₂ ),3.50(dd,J＝5.0,2.5Hz,1H,CH ₂ ),2.90(s,6H,CH ₃ ),2.86-2.80(m,2H,CH ₂ ),2.75-2.66(m,3H,CH ₂ ),2.58-2.52(m,1H,CH ₂ ),2.09-2.02(m,1H,CH ₂ ), 1.90-1.82 (m, 1H, CH ₂ ), 0.71 (s, 9H, CH ₃ ); ESI-MS: m/z＝656.4[M+H] ⁺ .

Example 58 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(4-(trifluoromethyl)phenyl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 167: 3-pyridinecarboxylic acid and compound 149 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 167. The yield was 64%. ¹ H NMR (500 MHz, DMSO) δ9.03 (d, J = 2.0 Hz, 1H, pyridine-H), 8.92 (d, J = 7.5 Hz, 1H, NH), 8.85 (d, J = 8.5 Hz, 1H, NH), 8.72 (dd, J = 5.0, 1.5 Hz, 1H, pyridine-H), 8.43 (d, J = 8.0 Hz, 1H, NH), 8.22-8.20 (m, 1H, pyridin e-H),7.95(t,J＝6.0Hz,1H,NH),7.52-7.50(m,1H,pyridine-H),7.27-7.20(m,4H,Ar-H),7.18-7.11(m,5H,Ar-H),5.22-5.16(m,1H,CH),4.88-4.83(m,1H,CH), 4.18-4.12(m,1H,CH),4.03-3.99(m,1H,CH ₂ ),3.62-3.60(m,1H,CH ₂ ),2.92(dd,J＝13.5,6.5Hz,1H,CH ₂ ),2.88-2.84(m,1H,CH ₂ ),2.71-2.68(m,2H,CH ₂ ),2.61-2.53(m,2H,CH ₂ ),2.13-2.06(m, 1H,CH ₂ ), 1.99-1.94 (m, 1H, CH ₂ ), 0.68 (s, 9H, CH ₃ ); ESI-MS: m/z=681.3[M+H] ⁺ .

Example 59 Preparation of N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxopropane-2-yl)pyrazine-2-carboxamide

Synthesis of compound 168: 2-pyrazinecarboxylic acid and compound 150 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 168. The yield was 62%. ¹ H NMR (400 MHz, DMSO) δ9.19 (d, J = 1.6 Hz, 1H, pyrazine-H), 8.90 (d, J = 2.4 Hz, 1H, pyrazine-H), 8.82 (d, J = 7.6 Hz, 1H, NH), 8.78-8.74 (m, 1H, pyrazine-H), 8.71 (d, J = 8.4 Hz, 1H, NH), 8.36 (d, J＝8.0Hz,1H,NH),7.44-7.36(m,2H,Ar-H),7.30-7.20(m,4H,Ar-H),7.20-7.13(m,3H,Ar-H),5.09-5.02(m,1H,CH),4.66-4.57(m,1H,CH),4.32-4.24(m,1 H,CH),3.94(t,J＝5.6Hz,1H,CH ₂ ),3.56(dd,J＝6.0,2.8Hz,1H,CH ₂ ),2.66-2.53(m,2H,CH ₂ ),2.04-1.82(m,2H,CH ₂ ),1.40(d,J＝6.8Hz,3H,CH ₃ ); ESI-MS: m/z＝519.2[M+H] ⁺ .

Example 60 Preparation of N-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)nicotinamide

Synthesis of compound 169: 3-pyridinecarboxylic acid and compound 150 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 169. The yield was 74%; ¹ H NMR (400 MHz, DMSO) δ9.05 (s, 1H, pyridine-H), 8.85 (d, J = 6.8 Hz, 1H, NH), 8.73-8.67 (m, 1H, NH), 8.62 (d, J = 8.0 Hz, 1H, NH), 8.26-8.12 (m, 2H, pyridine-H), 7.52-7.46 (m, 1H, pyri dine-H),7.42-7.34(m,2H,Ar-H),7.30-7.20(m,4H,Ar-H),7.20-7.10(m,3H,Ar-H),5.09-4.98(m,1H,CH),4.59-4.48(m,1H,CH),4.30-4.20(m,1H,CH),3.93(t,J＝4.4Hz,1H,CH ₂ ),3.60-3.50(m,1H,CH ₂ ),2.68-2.53(m,2H,CH ₂ ),2.04-1.82(m,2H,CH ₂ ),1.39(d,J＝6.8Hz,3H,CH ₃ )；ESI-MS:m/z＝518.2[M+H] ⁺ .

Example 61 Preparation of N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxopropane-2-yl)pyrazine-2-carboxamide

Synthesis of compound 170: 2-pyrazinecarboxylic acid and compound 151 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 170. The yield was 57%; ¹ H NMR(400MHz,DMSO)δ9.18(s,1H,pyrazine-H),8.89(d,J＝2.4Hz,1H,pyrazine-H),8.83(d,J＝7.6Hz,1H,NH),8.79-8.68(m,2H,pyrazine-H+NH),8.37(d,J＝8.0Hz,1H,NH),7.4 3-7.36(m,2H,Ar-H),7.30-7.20(m,4H,Ar-H),7.20-7.11(m,3H,Ar-H),5.07 -4.99(m,1H,CH),4.65-4.56(m,1H,CH),4.33-4.25(m,1H,CH),3.93(t,J＝5.2 Hz,1H,CH _{2 . ​ ​ ​} ^​

Example 62 Preparation of N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)nicotinamide

Synthesis of compound 171: 3-pyridinecarboxylic acid and compound 151 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 171. The yield was 55%. ¹ H NMR (400 MHz, DMSO) δ9.05 (d, J = 1.6 Hz, 1H, pyridine-H), 8.85 (d, J = 6.8 Hz, 1H, NH), 8.71-8.68 (m, 1H, pyridine-H), 8.64 (d, J = 8.0 Hz, 1H, NH), 8.26-8.17 (m, 2H, pyridine-H+NH), 7.47 (dd, J = 8.0 ,4.8Hz,1H,pyridine-H),7.44-7.34(m,2H,Ar-H),7.29-7.20(m,4H,Ar-H),7.20-7.14(m,3H,Ar-H),5.06-5.01(m,1H,CH),4.56-4.46(m,1H,CH),4.27-4.20( m,1H,CH),3.93(t,J＝5.6Hz,1H,CH ₂ ),3.57(dd,J＝5.6,2.8Hz,1H,CH ₂ ),2.70-2.53(m,2H,CH ₂ ),2.06-1.80(m,2H,CH ₂ ),1.39(d,J＝7.2Hz,3H,CH ₃ ); ESI-MS: m/z＝518.2[M+H] ⁺ .

Example 63 Preparation of N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-3-methyl-1-oxobutan-2-yl)pyrazine-2-carboxamide

Synthesis of compound 172: 2-pyrazinecarboxylic acid and compound 152 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 172. The yield was 65%; ¹ H NMR (400MHz, DMSO) δ9.26-9.17(m,1H,pyrazine-H),8.96-8.87(m,1H,pyrazine-H),8.84-8.72(m,2H,pyrazine-H+NH),8.55(d,J＝8.0Hz,1H,NH),8.50(d,J＝8.0Hz,1H,NH) ,7.45-7.33(m,2H,Ar-H),7.30-7.11(m,7H,Ar-H),5.12-5.00(m,1H,CH),4.59-4.48(m,1H,CH),4.28(m,1H,CH),3.94(m,1H,CH ₂ ),3.54(m,1H,CH ₂ ),2.68 -2.55(m,2H,CH ₂ ),2.23-2.11(m,1H,CH),2.02-1.81(m,2H,CH ₂ ),0.95(d,J＝4.8Hz,3H,CH ₃ ),0.89(d,J＝4.8Hz,3H,CH ₃ ); ESI-MS: m/z＝547.2[M+H] ⁺ .

Example 64 Preparation of N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-3-methyl-1-oxobutan-2-yl)nicotinamide

Synthesis of compound 173: 3-pyridinecarboxylic acid and compound 152 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 173. The yield was 63%; ¹ H NMR (400 MHz, DMSO) δ9.05 (d, J = 1.6 Hz, 1H, pyridine-H), 8.72 (dd, J = 4.4, 1.6 Hz, 1H, pyridine-H), 8.70 (d, J = 8.4 Hz, 1H, NH), 8.66 (d, J = 8.4 Hz, 1H, NH), 8.28 (d, J = 8.0 Hz, 1H, NH), 8.23 (d, J = 8.0 Hz, 1H, pyridine-H), 7.51(dd,J＝8.0,4.8Hz,1H,pyridine-H),7.44-7.36(m,2H,Ar-H),7.30-7.21(m,4H,Ar-H),7.21-7.14(m,3H,Ar-H),5.11-5.05(m,1H,CH),4.37(t,J＝8.0Hz,1 H,CH),4.31-4.23(m,1H,CH),3.95(t,J＝5.6Hz,1H,CH ₂ ),3.54(dd,J＝5.6,2.8Hz,1H,CH ₂ ),2.70-2.57(m,2H,CH ₂ ),2.24-2.14(m,1H,CH),2.03-1.87(m,2H,CH ₂ ),0.99(d,J＝6.0Hz,6H,CH ₃ ); ESI-MS: m/z＝546. 2[M+H] ⁺ .

Example 65 Preparation of N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxo-4-phenylbutan-2-yl)nicotinamide

Synthesis of compound 174: 3-pyridinecarboxylic acid and compound 153 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 174. The yield was 60%. ¹ H NMR (500 MHz, DMSO) δ9.08 (d, J = 1.6 Hz, 1H, pyridine-H), 8.88 (d, J = 7.4 Hz, 1H, NH), 8.73 (dd, J = 4.7, 1.5 Hz, 1H, NH), 8.69 (d, J = 8.1 Hz, 1H, pyridine-H), 8.28 (d, J = 7.8 Hz, 1H, NH), 8.26-8.22 (m, 1H, pyridine-H), 7.51(dd,J＝7.8,4.9Hz,1H,pyridine-H),7.42–7.36(m,2H,Ar-H),7.29–7.21(m,8H,Ar-H),7.20–7.13(m,4H,Ar-H),5.06–4.99(m,1H,CH),4.57–4.49(m,1H,CH) ),4.32–4.22(m,1H,CH),3.92(t,J＝5.6Hz,1H,CH ₂ ),3.56(dd,J＝5.4,2.7Hz,1H,CH ₂ ),2.79–2.63(m,3H,CH ₂ ),2.61–2.54(m,1H,CH ₂ ),2.17–1.94(m,3H,CH ₂ ),1.94–1.82(m,1H,CH ₂ ); ESI-MS: m/z＝608. 3[M+H] ⁺ .

Example 66 N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-1-oxo-3-phenylpropan-2-yl)nicotinamide

Synthesis of compound 175: 3-pyridinecarboxylic acid and compound 154 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 175. The yield was 65%. ¹ H NMR (500 MHz, DMSO) δ8.93 (d, J = 1.5 Hz, 1H, pyridine-H), 8.91 (d, J = 8.3 Hz, 1H, NH), 8.72 (d, J = 8.1 Hz, 1H, NH), 8.68 (dd, J = 4.8, 1.6 Hz, 1H, pyridine-H), 8.43 (d, J = 7.8 Hz, 1H, NH), 8.14-8.09 (m, 1H, pyridine -H),7.49–7.45(m,1H,pyridine-H),7.42–7.38(m,4H,Ar-H),7.29–7.24(m,6H,Ar-H),7.20–7.16(m,4H,Ar-H),5.08–5.01(m,1H,CH),4.84–4.78(m,1H,CH), 4.32–4.25(m,1H,CH),3.94(t,J＝5.6Hz,1H,CH ₂ ),3.58(dd,J＝5.5,2.8Hz,1H,CH ₂ ),3.21(dd,J＝13.8,3.9Hz,1H,CH ₂ ),3.01(dd,J＝13.8,11.0Hz,1H,CH ₂ ),2.71–2.55(m,2H,CH ₂ ),2.06–1.85(m,2H,CH ₂ ); ESI-MS: m/z＝594.3[M+H] ⁺ .

Example 67 Preparation of N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-4-(methylthio)-1-oxobutan-2-yl)nicotinamide

Synthesis of compound 176: 3-pyridinecarboxylic acid and compound 155 were used as raw materials. The synthesis and post-treatment were the same as in Example 49 to obtain white solid 176. The yield was 74%. ¹ H NMR (500 MHz, DMSO) δ9.04 (dd, J = 2.0, 0.5 Hz, 1H, pyridine-H), 8.89 (d, J = 7.0 Hz, 1H, NH), 8.69 (dd, J = 5.0, 1.5 Hz, 1H, pyridine-H), 8.65 (d, J = 8.0 Hz, 1H, NH), 8.58 (d, J = 8.0 Hz, 1H, NH), 8.18-8.12 (m, 1H ,pyridine-H),7.40-7.36(m,3H,pyridine-H+Ar-H),7.30-7.21(m,4H,Ar-H),7.20-7.15(m,3H,Ar-H),5.12-5.07(m,1H,CH),4.54(q,J＝7.0Hz,1H,CH),4.28-4.20( m,1H,CH),3.94(t,J＝6.0Hz,1H,CH ₂ ),3.50(dd,J＝5.5,2.5Hz,1H,CH ₂ ),2.69-2.58(m,2H,CH ₂ ),2.58-2.51(m,2H,CH ₂ ),2.07(s,3H,CH ₃ ),2.06-2.00(m,3H,CH ₃ ),1.91-1.82(m,1H,CH ₂ ); ESI-MS: m/z＝578.2[M+H] ⁺ .

Example 68 Preparation of (S)-2-Benzamido-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

Synthesis of compound 177: Compound 147 and benzoic acid were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 49 to obtain a white solid. Yield: 60%, ESI-MS: m/z = 642.3 [M+H] ⁺ .

Example 69 Preparation of (S)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(thiazole-2-carboxamide)succinamide

Synthesis of compound 178: Compound 147 and thiazole-2-carboxylic acid were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 49 to obtain a white solid. Yield: 64%. ESI-MS: m/z = 649.3 [M+H] ⁺ .

Example 70 Preparation of (S)-2-(4-fluorobenzamido)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazepin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

Synthesis of compound 179: Compound 147 and p-fluorobenzoic acid were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 49 to obtain a white solid. Yield: 61%. ESI-MS: m/z = 660.3 [M+H] ⁺ .

Example 71 Preparation of (S)-2-(4-methoxybenzamide)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazepin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinamide

Synthesis of compound 180: Compound 147 and p-methoxybenzoic acid were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 49 to obtain a white solid. Yield: 63%. ESI-MS: m/z = 672.3 [M+H] ⁺ .

Example 72 Preparation of N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)amino)-4-methyl-1-oxopentan-2-yl)nicotinamide

Synthesis of compound 181: Compound 156 and 3-pyridinecarboxylic acid were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 49 to obtain a white solid. The yield was 59%. ESI-MS: m/z = 560.3 [M+H] ⁺ .

Example 73 Preparation of (S)-N ¹ -((S)-1-((R)-1-(4-cyanophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Compound 147 was dissolved in dichloromethane, HOBt and EDCI were added at 0°C, and the mixture was reacted at room temperature for half an hour. Compound 87 and DIPEA were then added to the reaction system, and stirring was continued for three hours. After the reaction was completed, the reaction system was extracted with saturated aqueous NaHCO ₃ solution, saturated aqueous NH ₄ Cl solution and saturated aqueous NaCl solution in sequence. The organic layer was collected and dried with anhydrous sodium sulfate, and the solvent was removed by distillation under reduced pressure. The crude product was separated and purified by column chromatography (dichloromethane: ethyl acetate = 1:1) to obtain a white solid 182. Yield: 54%; ESI-MS: m/z = 638.3 [M+H] ⁺ .

Example 74 Preparation of (S)-N ¹ -((S)-1-((R)-1-(4-(carbamoyl)phenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 183: Compounds 157 and 88 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 50%. ESI-MS: m/z = 670.3 [M+H] ⁺ .

Example 75 Preparation of (S)-N ¹ -((S)-1-((R)-1-(4-bromophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 184: Compounds 157 and 89 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 65%. ESI-MS: m/z = 691.2 [M+H] ⁺ .

Example 76 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(pyrimidin-2-yl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 185: Compounds 157 and 90 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 67%. ESI-MS: m/z = 615.3 [M+H] ⁺ .

Example 77 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(pyridin-3-yl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 186: Compounds 157 and 91 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 62%. ESI-MS: m/z = 614.3 [M+H] ⁺ .

Example 78 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-((R)-1-(oxazol-2-yl)-2-oxazol-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)succinamide

Synthesis of compound 187: Compounds 157 and 92 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 56%. ESI-MS: m/z = 604.3 [M+H] ⁺ .

Example 79 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(thiazol-2-yl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 188: Compounds 157 and 93 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 54%. ESI-MS: m/z = 620.3 [M+H] ⁺ .

Example 80 Preparation of (S)-N ¹ -((S)-1-((R)-1-(isoxazol-3-yl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 189: Compounds 157 and 94 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 51%. ESI-MS: m/z = 604.3 [M+H] ⁺ .

Example 81 Preparation of (S)-N ¹ -((S)-1-((R)-1-(methylsulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 190: Compounds 157 and 95 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 50%. ESI-MS: m/z = 615.3 [M+H] ⁺ .

Example 82 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-p-tolylazetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 191: Compounds 157 and 96 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 60%. ESI-MS: m/z = 691.3 [M+H] ⁺ .

Example 83 Preparation of (S)-N ¹ -((S)-1-((R)-1-(tert-butyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 192: Compounds 157 and 97 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 62%. ESI-MS: m/z = 593.3 [M+H] ⁺ .

Example 84 Preparation of (S)-N ¹ -((S)-1-((R)-1-methyl-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 193: Compounds 157 and 98 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 63%. ESI-MS: m/z = 551.3 [M+H] ⁺ .

Example 85 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamido)-N ¹ -(S)-1-((R)-1-(oxetane-3-yl)-2-oxetane-3-yl)amino)-1-oxo-4-phenylbutane-2-yl)butanamide

Synthesis of compound 194: Compounds 157 and 99 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 65%. ESI-MS: m/z = 593.3 [M+H] ⁺ .

Example 86 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamido)-N ¹ -(S)-1-oxo-1-((R)-2-oxo-1-(tetrahydropyran-4-yl)azetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 195: Compounds 157 and 100 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 61%. ESI-MS: m/z = 621.3 [M+H] ⁺ .

Example 87 Preparation of (S)-N ¹ -((S)-1-((R)-1-((4-bromophenyl)sulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinamide

Synthesis of compound 196: Compounds 157 and 101 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 51%. ESI-MS: m/z = 755.2 [M+H] ⁺ .

Example 88 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamido)-N ¹ -((S)-1-((R)-1-((4-nitrophenyl)sulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)succinamide

Synthesis of compound 197: Compounds 157 and 102 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 53%. ESI-MS: m/z = 722.3 [M+H] ⁺ .

Example 89 Preparation of (S)-N ⁴ -neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-((trifluoromethyl)sulfonyl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide

Synthesis of compound 198: Compounds 157 and 103 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 60%. ESI-MS: m/z = 669.2 [M+H] ⁺ .

Example 90 Preparation of (S)-N ¹ -((S)-1-((R)-1-((8-(dimethylamino)naphthalen-2-yl)sulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamido)succinamide

Synthesis of compound 199: Compounds 157 and 104 were used as raw materials. The synthesis and post-treatment methods were the same as those in Example 73 to obtain a white solid. Yield: 47%. ESI-MS: m/z = 770.3 [M+H] ⁺ .

Experimental Example 1 Proteasome Inhibitory Activity Test of Short Peptide Compounds Containing β-Lactam Ring

Experimental method: The fluorescent substrate Suc-Leu-Leu-Val-Tyr-AMC was used to detect the activity, and the inhibition of enzyme activity by different compounds was observed to preliminarily evaluate the inhibitory effect of the compound. Proteasome chymotrypsin-like protease hydrolyzes the Tyr-AMC sequence in the substrate to release AMC. Under the conditions of excitation light 355nm and emission light 460nm, the fluorescence absorption value of the hydrolysis product AMC can be detected to observe the inhibition of the compound on proteasome activity. The positive reference used in the experiment is Bortezomib. The results are shown in Table 1.

Test for the proliferation inhibition activity of the short peptide compounds containing β-lactam ring of Experimental Examples 49-90 on multiple myeloma cells and acute leukemia cells

Experimental method: MTS method was used to detect cell viability, that is, cells growing in the logarithmic growth phase were digested with 0.01% trypsin, counted, and inoculated in 100 ml of a 96-well plate at a cell density of 2.0×10 ³ /well, and cultured overnight in a 5% CO ₂ incubator at 37°C. Six concentration gradients were set for each compound, and three replicate wells were set for each concentration. Each concentration was added to the corresponding wells, cultured in a 5% CO ₂ 37°C incubator for 72 hours, and 20 ml of 5 mg/ml MTS was added. After incubation at 37°C for 3 hours, the supernatant was discarded, 100 ml of DMSO was added to dissolve, and the light absorption value at 490 nm (L1) was measured using SpectraMAX 340, and the reference wavelength was 690 nm (L2). The (L1-L2) value was plotted against different concentrations of the inhibitor, and the IC ₅₀ was obtained by fitting the formula. The results are shown in Table 1.

Table 1 Inhibitory activity of the compounds on proteasome CT-L and proliferation inhibition activity on multiple myeloma cells and acute leukemia cells

Note: NT - not tested

Most of the compounds of the present invention have strong proteasome inhibition activity and blood malignant tumor cell proliferation inhibition activity. The above experiments show that the compounds have excellent anti-tumor application prospects and thus have good commercial value.

Claims (6)

1. A compound having the structure of general formula (I): in: R ₁ is selected from phenyl, pyridyl, pyrazinyl and thiazolyl, or phenyl substituted by fluorine atom or methoxy group; R ₂ is selected from C _1-6 alkyl, alkaryl, C _1-6 alkyl-DR _a , wherein D is selected from S, CONH, and R _a is selected from H, C _1-6 alkyl; the C _1-6 alkyl is selected from methyl, ethyl, isopropyl, isobutyl, and neopentyl, and the alkylaryl is selected from methylphenyl and ethylphenyl; R ₃ is selected from H, unsubstituted or substituted: C _1-6 alkyl, aryl, aralkyl, heterocyclyl and R _b -S(=O) ₂ -; the C _1-6 alkyl is selected from From methyl, tert-butyl, aryl is selected from benzene ring, naphthalene, the substituted C _1-6 alkyl, aryl, aralkyl, heterocyclyl, R _b -S (=O) ₂ - is Arbitrarily substituted by halogen, nitro, cyano, carbamoyl, N,N-dimethyl, halogenated C _1-4 alkyl, C _1-4 alkyl, C _1-4 alkoxy, aralkyl The base is selected from benzyl, phenethyl, and the heterocyclic group is selected from pyridyl, pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl, isoxazolyl, tetrahydropyranyl, and oxetanyl, R _b -S(=O) ₂ - is selected from methanesulfonyl, p-toluenesulfonyl, p-bromobenzenesulfonyl, nitrobenzenesulfonyl, trifluoromethanesulfonyl and dansyl. 2. The compound according to claim 1, characterized in that the compound is selected from: (S)-N ¹ -((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo- 4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(pyrazine-2-carboxamide)succinic acid amide; (S)-N ¹ -((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo- 4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo- 4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(pyrazine-2-carboxamide)succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo- 4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ⁴ -Neopentyl-2-nicotinamide-N ¹ -(S)-1-oxo-1-((S)-2-oxo-1-phenylazetidine -3-Ylamino)-4-phenylbutan-2-yl)succinamide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -(S)-1-oxo-1-((R)-2-oxo-1-phenyl azacycle Butan-3-ylamino)-4-phenylbutan-2-yl)succinamide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(p-tolyl) Azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinamide; (S)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-(4-(dimethylamino)phenyl)-2-oxoazetidin-3-yl)amino)-1 -Oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(4-(tri Fluoromethyl)phenyl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinimide; N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)pyrazine-2-carboxamide; N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)nicotinamide; N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)pyrazine-2-carboxamide; N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)amino)-1-oxopropan-2-yl)nicotinamide; N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)amino)-3-methyl-1-oxobutan-2-yl)pyrazine-2-carboxamide; N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)amino)-3-methyl-1-oxobutan-2-yl)nicotinamide; N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Substitute-4-phenylbutan-2-yl)amino)-1-oxo-4-phenylbutan-2-yl)nicotinamide; N-((S)-1-((S)-1-((S)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Substitute-4-phenylbutan-2-yl)amino)-1-oxo-3-phenylpropan-2-yl)nicotinamide; N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)amino)-4-(methylthio)-1-oxobutan-2-yl)nicotinamide; (S)-2-Benzamido-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl )Amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(thiazole-2-carboxamide)succinic acid amide; (S)-2-(4-fluorobenzamide)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazepine- 3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentylsuccinic acid amide; (S)-2-(4-methoxybenzamide)-N ¹ -((S)-1-((R)-1-(4-methoxyphenyl)-2-oxoazepine -3-yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl succinic acid amide; N-((S)-1-((S)-1-((R)-1-(4-fluorophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)amino)-4-methyl-1-oxopentan-2-yl)nicotinamide; (S)-N ¹ -((S)-1-((R)-1-(4-cyanophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo -4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-(4-(carbamoyl)phenyl)-2-oxoazetidin-3-yl)amino)-1 -Oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-(4-bromophenyl)-2-oxoazetidin-3-yl)amino)-1-oxo- 4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(pyrimidine-2- (base) azetidin-3-yl) amino)-4-phenylbutan-2-yl) succinic acid amide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(pyridine-3- (base) azetidin-3-yl) amino)-4-phenylbutan-2-yl) succinic acid amide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-((R)-1-(oxazol-2-yl)-2-oxazolyl -3-yl)amino)-1-oxo-4-phenylbutan-2-yl)succinic acid amide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-(thiazole-2- (base) azetidin-3-yl) amino)-4-phenylbutan-2-yl) succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-(isoxazol-3-yl)-2-oxoazetidin-3-yl)amino)-1-oxo Generation-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-(methanesulfonyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4- Phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-p-tolylaza Butan-3-yl)amino)-4-phenylbutan-2-yl)succinamide; (S)-N ¹ -((S)-1-((R)-1-(tert-butyl)-2-oxoazetidin-3-yl)amino)-1-oxo-4- Phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ¹ -((S)-1-((R)-1-methyl-2-oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutane -2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -(S)-1-((R)-1-(oxetan-3-yl)-2-oxo Heterocyclobutan-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)butanamide; (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -(S)-1-oxo-1-((R)-2-oxo-1-(tetrahydropyran) -4-yl)azetidin-3-ylamino)-4-phenylbutan-2-yl)succinamide; (S)-N ¹ -((S)-1-((R)-1-((4-bromophenyl)sulfonyl)-2-oxoazetidin-3-yl)amino)-1 -Oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-((R)-1-((4-nitrophenyl)sulfonyl)-2 -Oxoazetidin-3-yl)amino)-1-oxo-4-phenylbutan-2-yl)succinamide (S)-N ⁴ -Neopentyl-2-(nicotinamide)-N ¹ -((S)-1-oxo-1-((R)-2-oxo-1-((trifluoromethyl yl)sulfonyl)azetidin-3-yl)amino)-4-phenylbutan-2-yl)succinimide (S)-N ¹ -((S)-1-((R)-1-((8-(dimethylamino)naphthalen-2-yl)sulfonyl)-2-oxoazetidine-3 -(yl)amino)-1-oxo-4-phenylbutan-2-yl)-N ⁴ -neopentyl-2-(nicotinamide)succinic acid amide. 3. A pharmaceutical composition comprising at least one compound according to any one of claims 1-2, a pharmaceutically acceptable salt of the compound as an active component, and comprising one or A wider variety of pharmaceutically acceptable carriers or excipients. 4. The pharmaceutical composition according to claim 3, characterized in that the administration method of the pharmaceutical composition is selected from the group consisting of oral administration, injection, inhalation and implantation. 5. The pharmaceutical composition according to claim 3, characterized in that the dosage form of the pharmaceutical composition is injection, freeze-dried powder for injection, tablet, capsule or granule. 6. The compound of any one of claims 1-2, its pharmaceutically acceptable salt, or the use of the pharmaceutical composition of claim 3 in the preparation of multiple myeloma or acute leukemia drugs.