BIPHENYL DERIVATIVES FOR BLOCKING PD-1/PD-L1 INTERACTION, PREPARATION METHOD THEREFOR AND USE THEREOF

20220380342 · 2022-12-01

    Inventors

    Cpc classification

    International classification

    Abstract

    Biphenyl derivatives having a structure of formula (I) and capable of blocking PD-1/PD-L1 interaction, a preparation method therefor and use thereof. The series of compounds can be widely used in the preparation of medicaments for preventing and/or treating cancers or tumors, immune-related disease and disorders, communicable diseases, infectious diseases or metabolic diseases mediated by PD-1/PD-L1 signal pathways, and are expected to be developed into a new generation of PD-1/PD-L1 inhibitors.

    ##STR00001##

    Claims

    1. A compound of formula (I), a stereoisomer, prodrug or pharmaceutically acceptable salt thereof: ##STR00118## wherein, R.sub.1 is selected from the group consisting of ##STR00119## R.sub.2 is —NHR.sub.6 or 4-6 membered nitrogen-containing heterocyclyl, wherein a nitrogen atom is linked to methylene, and the 4-6 membered nitrogen-containing heterocyclyl is optionally further substituted with one or more substituents selected from the group consisting of deuterium, halogen, cyano, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, hydroxy-substituted C.sub.1-4 alkyl, C.sub.1-4 deuterioalkyl, C.sub.3-6 cycloalkyl, 4-6 membered heterocyclyl, hydroxy-substituted C.sub.3-6 cycloalkyl, carboxy-substituted C.sub.3-6 cycloalkyl, hydroxy-substituted 4-6 membered heterocyclyl, carboxy-substituted 4-6 membered heterocyclyl, hydroxy, C.sub.1-4 alkoxy, carboxy and C.sub.1-4 alkoxyacyl; R.sub.3, R.sub.4 and R.sub.5 are each independently selected from the group consisting of hydrogen, deuterium and C.sub.1-4 alkyl, the C.sub.1-4 alkyl is optionally further substituted with one or more substituents selected from the group consisting of deuterium, halogen, cyano, cyclopropyl, hydroxy and C.sub.1-4 alkoxy; R.sub.6 is selected from the group consisting of C.sub.1-4 alkyl, C.sub.3-6 cycloalkyl and C.sub.4-6 heterocyclyl, the heterocyclyl optionally contains 1-2 heteroatoms selected from N and O, above groups are optionally further substituted with one or more substituents selected from the group consisting of deuterium, halogen, cyano, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, hydroxy-substituted C.sub.1-4 alkyl, C.sub.1-4 deuterioalkyl, C.sub.3-6 cycloalkyl, 4-6 membered heterocyclyl, hydroxy-substituted C.sub.3-6 cycloalkyl, carboxy-substituted C.sub.3-6 cycloalkyl, hydroxy-substituted 4-6 membered heterocyclyl, carboxy-substituted 4-6 membered heterocyclyl, hydroxy, C.sub.1-4 alkoxy, carboxy and C.sub.1-4 alkoxyacyl; provided that when R.sub.1 is ##STR00120## R.sub.2 is different from R.sub.1.

    2. The compound of formula (I), the stereoisomer, prodrug or pharmaceutically acceptable salt thereof according to claim 1, wherein, R.sub.3, R.sub.4 and R.sub.5 are each independently selected from the group consisting of hydrogen, deuterium, methyl, ethyl and propyl, above groups are optionally further substituted with one or more substituents selected from the group consisting of deuterium, fluoro, chloro, bromo, cyano, cyclopropyl, hydroxy, methoxy and ethoxy; R.sub.6 is selected from the group consisting of methyl, ethyl, isopropyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, ##STR00121## above groups are optionally further substituted with one or more substituents selected from the group consisting of deuterium, fluoro, chloro, bromo, cyano, nitro, azido, methyl, ethyl, isopropyl, difluoromethyl, trifluoromethyl, dichloromethyl, trichloromethyl, dibromomethyl, tribromomethyl, dideuteriomethyl, trideuteriomethyl, hydroxymethyl, cyclopropyl, cyclobutyl, cyclopentyl, hydroxycyclopropyl, ##STR00122## hydroxy, methoxy, ethoxy, carboxy, methoxyacyl and ethoxyacyl.

    3. The compound of formula (I), the stereoisomer, prodrug or pharmaceutically acceptable salt thereof according to claim 1, wherein the compound of formula (I) is a compound having formula (IIa), formula (IIb), formula (IIc), formula (IId) or formula (IIe): ##STR00123## wherein R.sub.2 is —NHR.sub.6 or 4-6 membered nitrogen-containing heterocyclyl, wherein a nitrogen atom is linked to methylene, provided that R.sub.2 in the compound of formula (IIa) is not ##STR00124## R.sub.2 in the compound of formula (IIb) is not ##STR00125## R.sub.2 in the compound of formula (IIc) is not ##STR00126## the 4-6 membered nitrogen-containing heterocyclyl is selected from the following structures: ##STR00127## above groups are optionally further substituted with one or more substituents selected from the group consisting of deuterium, fluoro, chloro, bromo, cyano, methyl, ethyl, isopropyl, cyclopropyl, hydroxycyclopropyl, hydroxymethyl, hydroxy, methoxy, ethoxy, carboxy, methoxyacyl and ethoxyacyl; R.sub.3, R.sub.4 and R.sub.5 are each independently selected from the group consisting of hydrogen, deuterium, methyl and ethyl; R.sub.6 is selected from the group consisting of methyl, ethyl, isopropyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, ##STR00128## above groups are optionally further substituted with one or more substituents selected from the group consisting of deuterium, fluoro, chloro, bromo, cyano, methyl, ethyl, isopropyl, cyclopropyl, hydroxycyclopropyl, hydroxymethyl, hydroxy, methoxy, ethoxy, carboxy, methoxyacyl and ethoxyacyl.

    4. The compound of the formula (I), the stereoisomer, prodrug or pharmaceutically acceptable salt thereof according to claim 1, wherein the compound is selected from the following compounds: ##STR00129## ##STR00130## ##STR00131## ##STR00132## ##STR00133## ##STR00134## ##STR00135## ##STR00136## ##STR00137## ##STR00138## ##STR00139## ##STR00140## ##STR00141## ##STR00142##

    5. A method for preparing the compound of formula (I), the stereoisomer, prodrug or pharmaceutically acceptable salt thereof according to claim 1, comprising the following steps: ##STR00143## wherein, R.sub.a, R.sub.b, R.sub.c and R.sub.d are each independently C.sub.1-8 alkoxy, or R.sub.a together with R.sub.b, R.sub.c together with R.sub.d is ═O, and R.sub.1 and R.sub.2 are defined as in claim 1.

    6. A pharmaceutical composition, comprising the compound of formula (I), the stereoisomer, prodrug or pharmaceutically acceptable salt thereof according to claim 1, and a pharmaceutically acceptable carrier.

    7. Use of A method for preventing and/or treating a PD-1/PD-L1 signal pathway-mediated disease comprising administering the compound of formula (I), the stereoisomer, prodrug or pharmaceutically acceptable salt thereof according to claim 1 to a subject in need thereof.

    8. The method according to claim 7, wherein the PD-1/PD-L1 signal pathway-mediated disease is cancer or tumor, immune-related disease and disorder, communicable disease, infectious disease or metabolic disease.

    9. The method according to claim 8, wherein the infectious disease is bacterial infectious disease, viral infectious disease and fungal infectious disease; the cancer or tumor is lymphoma (including but not limited to lymphocytic lymphoma, primary central nervous system lymphoma, T cell lymphoma, diffuse large B cell lymphoma, follicle center lymphoma, Hodgkin lymphoma, non-Hodgkin lymphoma or primary mediastinal large B cell lymphoma), sarcoma (including but not limited to Kaposi's sarcoma, fibrosarcoma, liposarcoma, chondrosarcoma, osteosarcoma, leiomyosarcoma, rhabdomyosarcoma, soft tissue sarcoma, angiosarcoma or lymphangiosarcoma), melanoma, glioblastoma, synovioma, meningioma, biliary tract tumor, thymic tumor, neuroma, seminoma, nephroblastoma, pleomorphic adenoma, hepatocellular papilloma, renal tubule adenoma, cystadenoma, papilloma, adenoma, leiomyoma, rhabdomyoma, hemangioma, lymphangioma, osteoma, chondroma, lipoma, fibroma, central nervous system tumor, rhachiophyma, brain stem glioma, pituitary adenoma, multiple myeloma, ovarian tumor, myelodysplastic syndrome or mesothelioma, prostate cancer, recurrent prostate cancer or prostate cancer having developed resistance to existing medicaments, thyroid cancer, parathyroid cancer, anal cancer, testicular cancer, urethral carcinoma, penile cancer, bladder cancer, ureteral cancer, uterine cancer, ovarian cancer, fallopian tube cancer, endometrial cancer, cervical cancer, vaginal cancer, vulvar cancer, adrenal cancer, Merkel cell carcinoma, embryonal carcinoma, chronic or acute leukemia (including but not limited to acute myeloid leukemia, chronic myeloid leukemia, acute lymphoblastic leukemia, chronic granulocytic leukemia and chronic lymphoblastic leukemia), bronchial carcinoma, esophageal cancer, nasopharyngeal carcinoma, hepatocellular carcinoma, renal cell carcinoma, small cell lung cancer, basal cell carcinoma, lung cancer, breast cancer, adenocarcinoma, papillary carcinoma, cystadenocarcinoma, squamous non-small cell lung cancer, non-squamous non-small cell lung cancer, rectal cancer, colon cancer, colorectal cancer, gastric cancer, pancreatic cancer, head and neck squamous cell carcinoma, head and neck cancer, gastrointestinal cancer, bone cancer, skin cancer, small intestine cancer, endocrine system cancer, renal pelvic carcinoma, epidermoid carcinoma, abdominal wall carcinoma, renal cell carcinoma, transitional cell carcinoma, choriocarcinoma, or metastatic tumor, especially metastatic tumor expressing PD-L1; the immune-related disease and disorder is rheumatic arthritis, renal failure, lupus erythematosus, asthma, psoriasis, ulcerative colitis, pancreatitis, allergy, fibrosis, anemia, fibromyalgia, Alzheimer's disease, congestive heart failure, stroke, aortic valve stenosis, arteriosclerosis, osteoporosis, Parkinson's disease, infection, Crohn's disease, ulcerative colitis, allergic contact dermatitis and eczema, systemic sclerosis or multiple sclerosis; the communicable disease or infectious disease is sepsis, liver infection, HIV, hepatitis A, hepatitis B, hepatitis C, hepatitis D, herpes virus, papillomavirus or influenza; the metabolic disease is diabetes, diabetic ketoacidosis, hyperglycemic hyperosmolar syndrome, hypoglycemia, gout, malnutrition, vitamin A deficiency, scurvy, vitamin D deficiency or osteoporosis.

    10. (canceled)

    Description

    DETAILED DESCRIPTION OF THE INVENTION

    [0031] After extensive and intensive research, the inventors of the present invention, for the first time, developed a biphenyl series of compounds having the structure of the general formula (I). With a strong inhibitory effect on the interaction between PD-1 and PD-L1, the series of compounds of the present invention can be widely applied in the preparation of medicaments for preventing and/or treating cancer or tumor, immune-related disease and disorder, communicable disease, infectious disease or metabolic disease that is mediated by the PD-1/PD-L1 signal pathway, and are expected to be developed into a new generation of PD-1/PD-L1 inhibitors. The present invention is achieved on this basis.

    [0032] Detailed description: unless otherwise stated or specified, the following terms used in the specification and claims have the following meanings.

    [0033] “Alkyl” refers to linear or branched saturated aliphatic alkyl groups, for example, “C.sub.1-4 alkyl” refers to straight and branched chain alkyl groups comprising 1 to 4 carbon atoms, including but not limited to methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, sec-butyl, and the like. Alkyl may be optionally substituted or unsubstituted, and when it is substituted, the substituent is preferably one or more (preferably, 1, 2, 3 or 4) of the groups independently selected from the group consisting of deuterium, halogen, cyano, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, hydroxy-substituted C.sub.1-4 alkyl, C.sub.1-4 deuterioalkyl, C.sub.3-6 cycloalkyl, 4-6 membered heterocyclyl, hydroxy-substituted C.sub.3-6 cycloalkyl, carboxy-substituted C.sub.3-6 cycloalkyl, hydroxy-substituted 4-6 membered heterocyclyl, carboxy-substituted 4-6 membered heterocyclyl, hydroxy, C.sub.1-4 alkoxy, carboxy and C.sub.1-4 alkoxyacyl.

    [0034] “Cycloalkyl” refers to monocyclic or polycyclic hydrocarbon substituents that are saturated or partially unsaturated, for example, “C.sub.3-6 cycloalkyl” refers to monocyclic cycloalkyl containing 3 to 6 carbon atoms, including but not limited to cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cyclohexadienyl and the like. Cycloalkyl may be optionally substituted or unsubstituted, and when it is substituted, the substituent is preferably one or more (preferably, 1, 2, 3 or 4) of the groups independently selected from the group consisting of deuterium, halogen, cyano, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, hydroxy-substituted C.sub.1-4 alkyl, C.sub.1-4 deuterioalkyl, C.sub.3-6 cycloalkyl, 4-6 membered heterocyclyl, hydroxy-substituted C.sub.3-6 cycloalkyl, carboxy-substituted C.sub.3-6 cycloalkyl, hydroxy-substituted 4-6 membered heterocyclyl, carboxy-substituted 4-6 membered heterocyclyl, hydroxy, C.sub.1-4 alkoxy, carboxy and C.sub.1-4 alkoxyacyl.

    [0035] “Heterocyclyl” refers to a monocyclic hydrocarbon substituent that is saturated or partially unsaturated, wherein 1 or 2 (preferably, 1) ring atoms are heteroatoms selected from the group consisting of nitrogen, oxygen and S(O).sub.r (wherein r is an integer of 0, 1 or 2), excluding ring portions of —O—O—, —O—S— or —S—S—, and the remaining ring atoms are carbon atoms. For example, “4-6 membered heterocyclyl” refers to monocyclic heterocyclyl containing 4 to 6 ring atoms, including but not limited to pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, thiomorpholinyl, homopiperazinyl, and the like. Heterocyclyl may be optionally substituted or unsubstituted, and when it is substituted, the substituent is preferably one or more (preferably, 1, 2, 3 or 4) of the groups independently selected from the group consisting of deuterium, halogen, cyano, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, hydroxy-substituted C.sub.1-4 alkyl, C.sub.1-4 deuterioalkyl, C.sub.3-6 cycloalkyl, 4-6 membered heterocyclyl, hydroxy-substituted C.sub.3-6 cycloalkyl, carboxy-substituted C.sub.3-6 cycloalkyl, hydroxy-substituted 4-6 membered heterocyclyl, carboxy-substituted 4-6 membered heterocyclyl, hydroxy, C.sub.1-4 alkoxy, carboxy and C.sub.1-4 alkoxyacyl.

    [0036] “Alkoxy” refers to —O-(alkyl), wherein the alkyl is defined as above, for example, “C.sub.1-4 alkoxy” refers to an alkoxy containing 1 to 4 carbons atoms, including but not limited to methoxy, ethoxy, propoxy, butoxy, and the like. Alkoxy may be optionally substituted or unsubstituted, and when it is substituted, the substituent is preferably one or more (preferably, 1, 2, 3 or 4) of the groups independently selected from the group consisting of deuterium, halogen, cyano, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, hydroxy-substituted C.sub.1-4 alkyl, C.sub.1-4 deuterioalkyl, C.sub.3-6 cycloalkyl, 4-6 membered heterocyclyl, hydroxy-substituted C.sub.3-6 cycloalkyl, carboxy-substituted C.sub.3-6 cycloalkyl, hydroxy-substituted 4-6 membered heterocyclyl, carboxy-substituted 4-6 membered heterocyclyl, hydroxy, C.sub.1-4 alkoxy, carboxy and C.sub.1-4 alkoxyacyl.

    [0037] “C.sub.1-4 haloalkyl” refers to an alkyl having 1 to 4 carbon atoms in which hydrogens on the alkyl are optionally substituted with a fluorine, chlorine, bromine or iodine atom, including but not limited to difluoromethyl, dichloromethyl, dibromomethyl, trifluoromethyl, trichloromethyl, tribromomethyl, and the like.

    [0038] “C.sub.1-4 alkoxyacyl” refers to C.sub.1-4 alkoxy being linked to the carbonyl [C(O)], and is also generally referred to as “C.sub.1-4 alkyl-O—C(O)—”, for example, C.sub.1 alkoxyacyl may be referred to as “C.sub.1 alkyl-O—C(O)—”, and refers to methoxyacyl; C.sub.2 alkoxyacyl may be referred to as “C.sub.2 alkyl-O—C(O)—”, and refers to ethoxyacyl. “Halogen” refers to fluorine, chlorine, bromine or iodine. “PE” refers to petroleum ether, “EtOAc”/“EA” refers to ethyl acetate, “MeOH” refers to methanol, “DMF” refers to N,N-dimethylformamide, “THF” refers to tetrahydrofuran, “DIPEA” refers to N,N-diisopropylethylamine, “HATU” refers to 2-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate, “NaHCO.sub.3” refers to sodium bicarbonate, “KMnO.sub.4” refers to potassium permanganate, and “NaBH.sub.3CN” refers to sodium cyanoborohydride.

    [0039] The term “optional” or “optionally” means that the event or circumstance subsequently described may, but not necessarily, occur, and that the description includes instances where the event or circumstance occurs or does not occur, that is, instances where substitution occurs or does not occur. For example, “heterocyclyl group optionally substituted by alkyl” means that alkyl may be, but not necessarily, present, and that the description includes instances where the heterocyclyl group is or is not substituted by alkyl.

    [0040] The term “substituted” means that one or more hydrogen atoms in the group are each independently substituted by a corresponding number of substituents. It goes without saying that a substituent is only in its possible chemical position and consistent with Chemical Valence Bond Theory, and those skilled in the art will be able to determine (by experiments or theories) possible or impossible substitution without undue efforts. For example, it may be unstable when an amino or hydroxy having a free hydrogen is bound to a carbon atom having an unsaturated bond (such as olefin).

    [0041] “Stereoisomers” refer to isomers produced by different spatial arrangements of atoms in molecules, and can be classified into cis-trans isomers and enantiomers, and also into enantiomers and diastereomers. Stereoisomers resulting from rotation of single bonds are referred to as conformational stereo-isomers and sometimes also as rotamers. Stereoisomers resulting from bond lengths, bond angles, intramolecular double bonds, rings and the like are referred to as configuration stereo-isomers, and the configuration stereo-isomers are classified into two categories. Among them, isomers resulting from the fact that a double bond or a single bond of a ring-forming carbon atom cannot rotate freely are referred to as geometric isomers and also as cis-trans isomers, and the isomers are classified into Z, E configurations. For example, cis-2-butene and trans-2-butene are a pair of geometric isomers, and stereoisomers having different optical rotation properties due to the absence of anti-axisymmetry in the molecule are referred to as optical isomers, and are classified into R, S configurations. In the present invention, the term “stereoisomer” is understood to include one or more of the above enantiomers, configuration isomers and conformational isomers, unless otherwise specified.

    [0042] “Pharmaceutically acceptable salts” as used herein refers to pharmaceutically acceptable acid addition salts, including inorganic and organic acid salts, which may be prepared by methods known in the art.

    [0043] “Pharmaceutical composition” refers to a mixture containing one or more of the compounds described herein or a physiologically/pharmaceutically acceptable salt or pro-drug thereof, and other chemical components, for example physiologically/pharmaceutically acceptable carriers and excipients. The purpose of the pharmaceutical composition is to promote the administration to an organism, which facilitates the absorption of the active ingredient, thereby exerting biological activities.

    [0044] The present invention is further explained in detail below with reference to examples, which are not intended to limit the present invention, and the present invention is not merely limited to the contents of the examples.

    [0045] The compound structure of the present invention is determined by nuclear magnetic resonance (NMR) and/or liquid chromatography-mass spectrometry (LC-MS). The NMR chemical shift (δ) is given in parts per million (ppm). The NMR determination is conducted by using a Bruker AVANCE-400 or an AVANCE-500 nuclear magnetic resonance apparatus, with deuterated dimethyl sulfoxide (DMSO-d.sub.6), deuterated methanol (CD.sub.3OD), and deuterium oxide (D.sub.2O) and deuterated chloroform (CDCl.sub.3) as determination solvents, and tetramethylsilane (TMS) as internal standard.

    [0046] The LC-MS determination is conducted by using an Agilent 6120 mass spectrometer. The HPLC determination is conducted by using an Agilent 1200 DAD high pressure liquid chromatograph (Sunfire C18 150*4.6 mm chromatographic column) and a Waters 2695-2996 high pressure liquid chromatograph (Gimini C18 150*4.6 mm chromatographic column).

    [0047] Yantai Yellow Sea HSGF254 or Qingdao GF254 silica gel plate is adopted as a thin layer chromatography (TLC) silica gel plate. The specification adopted by the TLC is 0.15-0.20 mm, and the specification adopted by the thin layer chromatography for the separation and purification of products is 0.4-0.5 mm. The Yantai Yellow Sea silica gel of 200-300 mesh is generally utilized as a carrier in column chromatography.

    [0048] Starting materials in the examples of the present invention are known and commercially available, or may be synthesized by using or according to methods known in the art.

    [0049] Unless otherwise stated, all reactions of the present invention are carried out under a dry nitrogen or argon atmosphere with continuous magnetic stirring, wherein the solvent is a dry solvent, and the reaction temperature is in degree centigrade (° C.).

    PREPARATION OF EXAMPLES

    Example 1: Preparation of (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid

    [0050] ##STR00029##

    Step 1: Synthesis of 4-cyclopropyl-5-(dimethoxymethyl)-2-vinylpyridine

    [0051] ##STR00030##

    [0052] 4-cyclopropyl-6-vinyl-3-nicotinaldehyde (11.1 g, 64.0 mmol), trimethyl orthoformate (40.7 g, 384 mmol) and p-toluenesulfonic acid monohydrate (6.08 g, 32.0 mmol) were weighed and dissolved in absolute methanol (115 mL). The mixture were heated to 55° C. and stirred overnight. The reaction mixture was neutralized by adding an appropriate amount of DIPEA, and directly concentrated to obtain a crude product. The crude product was separated by silica gel column chromatography (PE/EA: 0-5%) to obtain 4-cyclopropyl-5-(dimethoxymethyl)-2-vinylpyridine (11.1 g, yield: 79%). MS m/z (ESI): 220.2 [M+H].sup.+.

    Step 2: Synthesis of potassium 4-cyclopropyl-5-(dimethoxymethyl)picolinate

    [0053] ##STR00031##

    [0054] 4-cyclopropyl-5-(dimethoxymethyl)-2-vinylpyridine (4.0 g, 23.1 mmol) was dissolved in a mixture of acetone/water (60 mL, v/v=2:1) and KMnO.sub.4 (8.56 g, 69.3 mmol) was added in batches. The reaction solution was stirred at room temperature overnight and heated to 40° C. and then reacted for 6 hrs. After the reaction was completed, the resulting reaction mixture was filtered, and washed with MeOH/CH.sub.3CN (50 mL, v/v=1:1). The filtrate was combined, added with active carbon, heated to 40° C. and stirred for 0.5 hrs, filtered while hot, and washed by adding H.sub.2O (20 mL). The filtrate was concentrated under reduced pressure to remove most of the organic solvent, and the remaining aqueous phase was lyophilized to obtain potassium 4-cyclopropyl-5-(dimethoxymethyl)picolinate (5.1 g, crude).

    Step 3: Synthesis of 4-cyclopropyl-5-formylpicolinic acid

    [0055] ##STR00032##

    [0056] Potassium 4-cyclopropyl-5-(dimethoxymethyl)picolinate (2.7 g, 9.8 mmol) was dissolved in pure water (20 mL), the reaction solution was added with a hydrochloric acid solution (10 L, 4.0 M), and stirred at room temperature for about 2 hrs. After the reaction was completed, the reaction solution was lyophilized to obtain 4-cyclopropyl-5-formylpicolinic acid (2.2 g, crude). MS m/z (ESI): 189.8 [M−H].sup.−.

    Step 4: Synthesis of 4-cyclopropyl-N-(3′-(4-cyclopropyl-5-(dimethoxymethyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)-5-formylpicolinamide

    [0057] ##STR00033##

    [0058] Potassium 4-cyclopropyl-5-(dimethoxymethyl)picolinate (622 mg, 2.27 mmol), HATU (854 mg, 2.06 mmol), 2,2′-dimethyl-[1,1′-diphenyl]-3,3′-diamine (435 mg, 2.05 mmol) an d DIPEA (1.0 mL) were weighed into a 100 mL eggplant-shaped flask, THF/MTBE (12 mL, 1:1) was added, and the mixture was stirred at room temperature overnight. The reaction solution was added with 4-cyclopropyl-5-formylpicolinic acid (452 mg, 2.0 mmol), HATU (598 mg, 1.57 mmol), and DMF (1.0 mL), and stirred at room temperature for 3 hrs. The reaction solution was added with water (20 mL) and extracted 2 times with h EtOAc (50 mL), and the organic phase was washed with brine (10 mL). The reaction solution was dried over anhydrous Na.sub.2SO.sub.4, filtered and concentrated to obtain a crude product. The crude product was separated by silica gel column chromatography (PE/EA: 0-12%) to obtain 4-cyclopropyl-N-(3′-(4-cyclopropyl-5-(dimethoxymethyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)-5-formylpicolinamide (344 mg, yield: 28%). MS m/z (ESI): 651.6 [M+H].sup.+.

    Step 5: Synthesis of (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-formylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid

    [0059] ##STR00034##

    [0060] 4-cyclopropyl-N-(3′-(4-cyclopropyl-5-(dimethoxymethyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)-5-formylpicolinamide (266 mg, 0.439 mmol) and (S)-piperidine-2-carboxylic acid (227 mg, 1.756 mmol) were added to a mixture solvent of CH.sub.2Cl.sub.2/DIPEA (20 mL, 4:1), and the mixture was heated to reflux and stirred for 22 hrs. The reaction solution was added with NaBH(OAc).sub.3 (372.3 mg, 1.756 mmol), stirred and reacted for 2 hrs at reflux. After the reaction was completed, the reaction solution was separated by reversed-phase column chromatography, and the collected resulting solution was concentrated to remove the organic solvent, added with a hydrochloric acid solution (4.0 mL, 4 M) and stirred for 2 hrs. The reaction solution was lyophilized to obtain (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-formylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid (153 mg, yield: 52%). MS m/z (ESI): 670.2 [M−H].sup.−.

    Step 6: Synthesis of (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid

    [0061] ##STR00035##

    [0062] (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-formylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid (48.0 mg, 0.071 mmol), ethanolamine (22.0 mg, 0.357 mmol) and DIPEA (0.1 mL, 0.43 mmol) were dis solved in DMF/HOAc (3 mL, 5:1), and the reaction solution was stirred at room temper attire for 2 hrs. The reaction solution was added with NaBH.sub.3CN (22.4 mg, 0.355 mmol), and stirred at room temperature for 1 hr. After the reaction was completed, 3 drops of methanol was added to terminate the reaction. The crude product was separated by re versed-phase column chromatography to obtain (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid (26.5 mg, yield: 52%). MS m/z (ESI): 715.4 [M−H].sup.−.

    [0063] .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.33 (s, 1H), 10.31 (s, 1H), 8.62 (s, 1H), 8.52 (s, 1H), 7.86 (t, J=7.9 Hz, 2H), 7.61 (s, 1H), 7.59 (s, 1H), 7.32 (t, J=7.8 Hz, 2H), 6.98 (dd, J=7.6, 4.5 Hz, 2H), 4.17 (s, 2H), 4.03 (d, J=13.7 Hz, 1H), 3.71 (d, J=13.6 Hz, 1H), 3.58 (t, J=5.7 Hz, 2H), 3.19 (t, J=5.6 Hz, 1H), 2.90-2.79 (m, 2H), 2.33-2.19 (m, 2H), 2.00 (s, 6H), 1.84-1.72 (m, 2H), 1.55-1.36 (m, 4H), 1.24 (d, J=6.7 Hz, 2H), 1.20-1.06 (m, 4H), 0.95-0.85 (m, 4H).

    [0064] Examples 2 to 28 were prepared by selecting corresponding raw materials according to all or part of the synthesis method in Example 1.

    TABLE-US-00001 Example MS: m/z No. Structure Name [M + 1].sup.+ 2 [00036]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((R)-1-hydroxypropan-2- yl)amino)methyl)picolinamido)-2,2′-di methyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 731.6 3 [00037]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((R)-1-hydroxypropan-2- yl)amino)methyl)picolinamido)-2,2′-di methyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 731.6 4 [00038]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((1S,2S)-2-hydroxycyclopentyl) amino)methyl)picolinamido)-2, 2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine- 2-carboxylic acid 757.6 5 [00039]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((1S,2R)-2-hydroxycyclopentyl) amino)methyl)picolinamido)-2, 2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)piperidine- 2-carboxylic acid 757.6 6 [00040]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((1R,2R)-2-hydroxycyclopentyl) amino)methyl)picolinamido)-2, 2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)piperidine- 2-carboxylic acid 757.6 7 [00041]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((methylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl)methyl) piperidine-2-carboxylic acid 687.4 8 [00042]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((ethylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl)methyl) piperidine-2-carboxylic acid 701.4 9 [00043]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((isopropylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl)methyl) piperidine-2-carboxylic acid 715.4 10 [00044]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((cyclopropylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl)methyl) piperidine-2-carboxylic acid 713.4 11 [00045]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((cyclopentylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl)methyl) piperidine-2-carboxylic acid 741.7 12 [00046]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((pyrrolidin-1-ylmethyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl)methyl) piperidine-2-carboxylic acid 727.6 13 [00047]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-(((R)-3-hydroxypyrrolidin-1-yl) methyl)picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)pyridin-3-yl) methyl)piperidine-2-carboxylic acid 743.6 14 [00048]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-(((S)-3-hydroxypyrrolidin-1-yl) methyl)picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)pyridin-3-yl) methyl)piperidine-2-carboxylic acid 743.6 15 [00049]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((3-hydroxy-3-methylazetidin- 1-yl)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 743.4 16 [00050]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((3-hydroxyazetidin-1-yl)methyl) picolinamido)-2,2′-dimethyl-[1, 1′-biphenyl]-3-yl)carbamoyl)pyridin- 3-yl)methyl)piperidine-2-carboxylic acid 729.4 17 [00051]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-(((2-hydroxy-2-methylpropyl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 745.4 18 [00052]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((1-hydroxycyclopropyl) methyl)amino)methyl)picolinamido)-2, 2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)piperidine- 2-carboxylic acid 743.4 19 [00053]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((3-methoxy-3-methylazetidin- 1-yl)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 757.4 20 [00054]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((3-methoxyazetidin-1-yl) methyl)picolinamido)-2,2′-dimethyl-[1, 1′-biphenyl]-3-yl)carbamoyl)pyridin- 3-yl)methyl)piperidine-2-carboxylic acid 743.4 21 [00055]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((1s,3s)-3-hydroxycyclobutyl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 743.4 22 [00056]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((1r,3r)-3-hydroxycyclobutyl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 743.4 23 [00057]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((oxetan-3-ylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)pyridin-3-yl) methyl)piperidine-2-carboxylic acid 729.4 24 [00058]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-(((tetrahydro-2H-pyran-4-yl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 757.4 25 [00059]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((S)-tetrahydrofuran-3-yl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)piperidine-2- carboxylic acid 743.6 26 [00060]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-((((R)-tetrahydrofuran-3-yl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)piperidine- 2-carboxylic acid 743.4 27 [00061]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-(((S)-2-(hydroxymethyl) pyrolidin-1-yl)methyl)picolinamido)-2, 2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)piperidine- 2-carboxylic acid 757.4 28 [00062]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4-cyclo propyl-5-(((R)-2-(hydroxymethyl) pyrolidin-1-yl)methyl)picolinamido)-2, 2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)piperidine- 2-carboxylic acid 757.4

    Example 29: Preparation of (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-((((R)-1-ethoxy-3-hydroxy-1-oxopropan-2-yl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid

    [0065] ##STR00063##

    [0066] (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-formylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid (50.0 mg, 0.074 mmol), d-serine ethyl ester hydrochloride (63.0 mg, 0.372 mmol) and DIPEA (0.07 mL, 0.372 mmol) were dissolved in DMF/HOAc (3 mL/1 mL), and the reaction solution was stirred at room temperature for 2 hrs. The reaction solution was added with NaBH.sub.3CN (23.0 mg, 0.372 mmol), and stirred at room temperature for 16 hrs. After the reaction was completed, 3 drops of methanol was added to terminate the reaction. The crude product was separated by reversed-phase column chromatography to obtain (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-((((R)-1-ethoxy-3-hydroxy-1-oxopropan-2-yl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl) piperidine-2-carboxylic acid (32 mg, yield: 55%). MS m/z (ESI): 789.4 [M+H].sup.+.

    [0067] .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.36 (s, 1H), 10.33 (s, 1H), 8.71 (s, 1H), 8.57 (s, 1H), 7.82 (dd, J=15.3, 8.0 Hz, 2H), 7.64 (s, 1H), 7.60 (s, 1H), 7.33 (t, J=7.9 Hz, 2H), 7.00 (t, J=6.9 Hz, 2H), 4.45 (brs, 2H), 4.22 (q, J=7.1, 6.6 Hz, 2H), 3.92 (brs, 2H), 3.00-2.85 (m, 2H), 2.45-2.40 (m, 2H), 2.36-2.28 (m, 2H), 2.00 (d, J=3.3 Hz, 6H), 1.80-1.70 (m, 2H), 1.65-1.40 (m, 4H), 1.25 (t, J=7.1 Hz, 3H), 1.21-1.08 (m, 4H), 1.00-0.75 (m, 4H).

    Example 30: Preparation of (S)-1-((6-((3′-(5-((((R)-1-carboxy-2-hydroxyethyl)amino)methyl)-4-cyclopropylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)-4-cyclopropylpyridin-3-yl)methyl)piperidine-2-carboxylic acid

    [0068] ##STR00064##

    [0069] (S)-1-((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-((((R)-1-ethoxy-3-hydroxy-1-oxopropan-2-yl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)piperidine-2-carboxylic acid (17.0 mg, 0.022 mmol) was dissolved in methanol/tetrahydrofuran/water (1 mL/1 mL/1 mL), and then the reaction solution was added with LiOH.H.sub.2O (9 mg, 0.22 mmol) and reacted at room temperature for 1 hr. After the reaction was completed, the reaction solution was concentrated and adjusted to weak acidity with HCl (1 N), and the crude product was separated by reversed-phase column chromatography to obtain (S)-1-((6-((3′-(5-((((R)-1-carboxy-2-hydroxyethyl)amino)methyl)-4-cyclopropylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)-4-cyclopropylpyridin-3-yl)methyl)piperidine-2-carboxylic acid (12 mg, yield: 73%). MS m/z (ESI): 761.4 [M+H].sup.+.

    [0070] .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 1H), 10.30 (s, 1H). 8.59 (s, 1H), 8.52 (s, 1H), 7.87 (dd, J=8.0, 4.2 Hz, 2H), 7.60 (s, 1H), 7.59 (s, 1H), 7.32 (t, J=7.8 Hz, 2H), 6.98 (d, J=7.7 Hz, 2H), 4.16 (d, J=13.8 Hz, 1H), 4.02 (dd, J=13.7, 5.9 Hz, 2H), 3.76-3.63 (m, 2H), 3.24-3.16 (m, 2H), 2.90-2.79 (m, 1H), 2.48-2.40 (m, 1H), 2.37-2.20 (m, 3H), 2.01 (s, 6H), 1.83-1.71 (m, 2H), 1.53-1.38 (m, 4H), 1.18-1.05 (m, 4H), 0.94-0.73 (m, 4H).

    [0071] Examples 31 to 34 were prepared by selecting corresponding raw materials according to all or part of the synthesis method in Example 29 or 30.

    TABLE-US-00002 Ex- ample MS: m/z No. Structure Name [M + H].sup.+ 31 [00065]embedded image (S)-1-((4-cyclopropyl-6-((3′-(4- cyclopropyl-5-((((S)-1-ethoxy-3- hydroxy-1-oxopropan-2-yl)amino) methyl)picolinamido)- 2,2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl) piperidine-2-carboxylic acid 789.4 32 [00066]embedded image (S)-1-((6-((3′-(5-((((S)-1-carboxy-2- hydroxyethyl)amino)methyl)-4- cyclopropylpicolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl)-4- cyclopropylpyridin-3-yl)methyl) piperidine-2-carboxylic acid 761.4 33 [00067]embedded image (S)-1-((6-((3′-(5-((((R)-2-carboxy-1- hydroxypropan-2-yl)amino)methyl)-4- cyclopropylpicolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl)-4- cyclopropylpyridin-3-yl)methyl) piperidine-2-carboxylic acid 775.4 34 [00068]embedded image (S)-1-((6-((3′-(5-((((S)-2-carboxy-1- hydroxypropan-2-yl)amino)methyl)-4- cyclopropylpicolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl)-4- cyclopropylpyridin-3-yl)methyl) piperidine-2-carboxylic acid 775.4

    Example 35: Preparation of ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serine

    [0072] ##STR00069##

    Step 1: Synthesis of ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(dimethoxymethyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate

    [0073] ##STR00070##

    [0074] 4-cyclopropyl-N-(3′-(4-cyclopropyl-5-(dimethoxymethyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)-5-formylpicolinamide (300 mg, 0.497 mmol) was dissolved in DMF (3 mL), and the reaction solution was added with d-serine ethyl ester hydrochloride (420 mg, 2.48 mmol), triethylamine (250 mg, 2.48 mmol) and acetic acid (1 mL). The reaction solution was stirred at room temperature for 2 hrs, then added with NaBH.sub.3CN (94 mg, 1.49 mmol) and stirred at room temperature overnight. After the reaction was completed as detected by LCMS, the reaction solution was directly separated by reversed-phase column chromatography to obtain ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(dimethoxymethyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (300 mg, yield: 84%). MS m/z (ESI): 722.4 [M+H].sup.+.

    Step 2: Synthesis of ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-formylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate

    [0075] ##STR00071##

    [0076] Ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(dimethoxymethyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (300 mg, 0.416 mmol) was dissolved in THF (10 mL), and the reaction solution was added with a hydrochloric acid solution (10 mL, 4 M) with stirring and stirred at room temperature for 1 hr. After the reaction was completed as detected by LCMS, the reaction system was cooled in an ice bath and neutralized by adding a saturated aqueous NaHCO.sub.3 solution. The reaction solution was extracted 3 times with ethyl acetate (20 mL), the organic phases were combined, washed with brine, dried over anhydrous Na.sub.2SO.sub.4, filtered and concentrated to obtain a crude product (260 mg, yield: 93%), which was directly used in the next step. MS m/z (ESI): 676.6 [M+H].sup.+.

    Step 3: Synthesis of ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (Example 35-1)

    [0077] ##STR00072##

    [0078] Ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-formylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (60 mg, 0.089 mmol) was dissolved in DMF (3 mL), and the reaction solution was added with 2-aminoethanol (54 mg, 0.8 9 mmol) and acetic acid (1 mL). The reaction solution was stirred at room temperature for 2 hrs, then added with NaBH.sub.3CN (17 mg, 0.267 mmol) and stirred overnight. After the reaction was completed as detected by LCMS, the reaction solution was directly separated by reversed-phase column chromatography to obtain ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (45 mg, yield: 70%). MS m/z (ESI): 721.4 [M+H].sup.+; 361.2 [½M+H].sup.+.

    [0079] .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.59 (s, 1H), 8.54 (s, 1H), 7.87 (d, J=8.2 Hz, 2H), 7.60 (s, 1H), 7.59 (s, 1H), 7.32 (t, J=7.8 Hz, 2H), 6.98 (d, J=7.6 Hz, 2H), 4.85 (t, J=5.8 Hz, 1H), 4.15-4.00 (m, 5H), 3.90 (d, J=13.7 Hz, 1H), 3.61 (t, J=5.2 Hz, 2H), 3.56-3.48 (m, 2H), 2.74 (brs, 2H), 2.37-2.22 (m, 2H), 2.00 (s, 6H), 1.20 (t, J=7.1 Hz, 3H), 1.19-1.06 (m, 4H), 0.92-0.79 (m, 4H).

    Step 4: Synthesis of ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serine

    [0080] ##STR00073##

    [0081] Ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (20 mg, 0.028 mmol) was dissolved in THF (3 mL) and water (3 mL), and then the reaction solution was added with LiOH.H.sub.2O (6 mg, 0.14 mmol) and stirred at room temperature for 1 hr. After the reaction was completed as detected by LCMS, the reaction solution was adjusted to pH<7 with acetic acid, and directly separated by reversed-phase column chromatography to obtain ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-(((2-hydroxyethyl)amino)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serine (15 mg, yield: 78%). MS m/z (ESI): 693.4 [M+H].sup.+; 347.2 [½M+H].sup.+.

    [0082] .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 2H), 8.61 (s, 1H), 8.59 (s, 1H), 7.87 (d, J=8.1 Hz, 2H), 7.61 (s, 1H), 7.60 (s, 1H), 7.32 (t, J=7.8 Hz, 2H), 6.98 (d, J=7.7 Hz, 1H), 4.20-4.10 (m, 3H), 3.99 (d, J=13.7 Hz, 1H), 3.65 (t, J=5.7 Hz, 2H), 3.57 (t, J=5.6 Hz, 2H), 3.28 (t, J=5.0 Hz, 1H), 2.80 (t, J=5.6 Hz, 2H), 2.40-2.22 (m, 2H), 2.00 (s, 6H), 1.20-1.08 (m, 4H), 0.95-0.80 (m, 4H).

    Example 36: Preparation of ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-((3-hydroxy-3-methylazetidin-1-yl)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serine

    [0083] ##STR00074##

    Step 1: Synthesis of ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-((3-hydroxy-3-methylazetidin-1-yl)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (Example 36-1)

    [0084] ##STR00075##

    [0085] Ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-formylpicolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)-D-serinate (60 mg, 0.089 mmol) was dissolved in DMF (3 mL), and 3-methylazetidine-3-ol hydrochloride (33 mg, 0.267 mmol), triethylamine (27 mg, 0.267 mmol) and acetic acid (1 mL) were successively added. The reaction solution was stirred at room temperature for 2 hrs, then added with NaBH.sub.3CN (17 mg, 0.267 mmol) and stirred overnight. After the reaction was completed as detected by LCMS, the reaction solution was directly separated by reversed-phase column chromatography to obtain ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-((3-hydroxy-3-methylazetidin-1-yl)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (40 mg, yield: 60%). MS m/z (ESI): 747.4 [M+H].sup.+; 374.2 [½M+H].sup.+.

    [0086] .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 1H), 10.29 (s, 1H), 8.54 (s, 1H), 8.48 (s, 1H), 7.88 (d, J=8.1 Hz, 2H), 7.59 (s, 2H), 7.31 (t, J=7.8 Hz, 2H), 6.98 (d, J=7.5 Hz, 2H), 5.19 (s, 1H), 4.85 (s, 1H), 4.15-4.01 (m, 3H), 3.90 (dd, J=13.5, 5.7 Hz, 1H), 3.85 (s, 2H), 3.61 (brs, 2H), 3.23 (d, J=6.8 Hz, 2H), 2.99 (d, J=6.4 Hz, 2H), 2.35-2.19 (m, 2H), 2.00 (s, 6H), 1.38 (s, 3H), 1.20 (t, J=7.1 Hz, 3H), 1.12 (d, J=8.1 Hz, 4H), 0.90-0.80 (m, 4H).

    Step 2: Synthesis of ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-((3-hydroxy-3-methylazetidin-1-yl)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serine

    [0087] ##STR00076##

    [0088] Ethyl ((4-cyclopropyl-6-((3′-(4-cyclopropyl-5-((3-hydroxy-3-methylazetidin-1-yl)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serinate (15 mg, 0.02 mmol) was dissolved in THF (3 mL) and water (3 mL), and then the reaction solution was added with LiOH.H.sub.2O (4 mg, 0.10 mmol) and stirred at room temperature for 1 hr. After the reaction was completed as detected by LCMS, the reaction solution was adjusted to pH<7 with acetic acid and then separated by reversed-phase column chromatography to obtain ((4-cyclopropyl-6-((3c-(4-cyclopropyl-54(3-hydroxy-3-methylazetidin-1-yl)methyl)picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)pyridin-3-yl)methyl)-D-serine (10 mg, yield: 69%). MS m/z (ESI): 719.4 [M+H].sup.+; 360.2 [½M+H].sup.+.

    [0089] .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.33 (s, 1H), 10.30 (s, 1H). 8.59 (s, 1H), 8.48 (s, 1H), 7.88 (d, J=8.0 Hz, 1H), 7.87 (d, J=8.0 Hz, 1H), 7.60 (s, 1H), 7.59 (s, 1H), 7.32 (t, J=7.8 Hz, 2H), 6.98 (d, J=7.6 Hz, 2H), 5.21 (s, 1H), 4.13 (d, J=13.8 Hz, 1H), 3.98 (d, J=13.5 Hz, 1H), 3.86 (s, 2H), 3.60 (d, J=5.4 Hz, 2H), 3.24 (d, J=6.8 Hz, 2H), 3.25-3.15 (m, 1H), 3.00 (d, J=6.7 Hz, 2H), 2.36-2.24 (m, 2H), 2.01 (s, 6H), 1.38 (s, 3H), 1.19-1.08 (m, 4H), 0.90-0.82 (m, 4H).

    [0090] Examples 37 to 66 were prepared by selecting corresponding raw materials according to all or part of the synthesis method in Example 35 or 36.

    TABLE-US-00003 Ex- ample MS: m/z No. Structure Name [M + H].sup.+ 37-1 [00077]embedded image Ethyl ((4-cyclopropyl-6-((3′-(4- cyclopropyl-5-(((2-hydroxyethyl)amino) methyl)picolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl)pyridin- 3-yl)methyl)-L-serinate 721.5 37    [00078]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-(((2-hydroxyethyl)amino)methyl) picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)pyridin-3-yl) methyl)-L-serine 693.6 38-1 [00079]embedded image Ethyl ((4-cyclopropyl-6-((3′-(4- cyclopropyl-5-((((R)-1-hydroxypropan-2- yl)amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serinate 735.6 38    [00080]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((((R)-1-hydroxypropan-2-yl)amino) methyl)picolinamido)-2,2-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl)pyridin- 3-yl)methyl)-D-serine 707.4 39-1 [00081]embedded image Ethyl ((4-cyclopropyl-6-((3′-(4- cyclopropyl-5-((((S)-1-hydroxypropan-2- yl)amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serinate 735.6 39    [00082]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((((S)-1-hydroxypropan-2-yl)amino) methyl)picolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl)pyridin- 3-yl)methyl)-D-serine 606.4 40    [00083]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((((1S,2S)-2-hydroxycyclopentyl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 733.4 41    [00084]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((((1R,2R)-2-hydroxycyclopentyl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 733.4 42    [00085]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((methylamino)methyl)picolinamido)- 2,2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)-D- serine 663.4 43    [00086]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((ethylamino)methyl)picolinamido)- 2,2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)-D- serine 677.4 44    [00087]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((isopropylamino)methyl)picolinamido)- 2,2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)-D- serine 691.4 45    [00088]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((cyclopropylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl) methyl)-D-serine 689.4 46    [00089]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((cyclobutylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl) methyl)-D-serine 703.4 47    [00090]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((oxetan-3-ylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl) methyl)-D-serine 705.4 48    [00091]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((cyclopentylamino)methyl) picolinamido)-2,2′-dimethyl-[1,1′-biphenyl]- 3-yl)carbamoyl)pyridin-3-yl) methyl)-D-serine 717.4 49    [00092]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((((S)-tetrahydrofuran-3-yl)amino) methyl)picolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl)pyridin- 3-yl)methyl)-D-serine 719.4 50    [00093]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-(pyrrolidin-1-ylmethyl)picolinamido)- 2,2′-dimethyl-[1,1′-biphenyl]-3-yl) carbamoyl)pyridin-3-yl)methyl)-D- serine 703.4 51    [00094]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-(((tetrahydro-2H-pyran-4-yl)amino) methyl)picolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl)pyridin- 3-yl)methyl)-D-serine 733.4 52    [00095]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-(((S)-3-hydroxypyrrolidin-1-yl) methyl)picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)pyridin-3- yl)methyl)-D-serine 719.4 53-1 [00096]embedded image Ethyl ((4-cyclopropyl-6-((3′-(4- cyclopropyl-5-(((R)-3-hydroxypyrrolidin- 1-yl)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serinate 747.6 53    [00097]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-(((R)-3-hydroxypyrrolidin-1-yl) methyl)picolinamido)-2,2′-dimethyl-[1, 1′-biphenyl]-3-yl)carbamoyl)pyridin- 3-yl)methyl)-D-serine 719.6 54    [00098]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-(((S)-2-hydroxymethyl)pyrrolidin- 1-yl)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 733.4 55    [00099]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-(((R)-2-hydroxymethyl)pyrrolidin- 1-yl)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 733.4 56    [00100]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((3-hydrdoxyazetidin-1-yl)methyl) picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)pyridin-3-yl) methyl)-D-serine 705.4 57    [00101]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((3-methoxy-3-methylazetidin-1-yl) methyl)picolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 733.4 58    [00102]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((3-methoxyazetidin-1-yl)methyl) picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)pyridin-3-yl) methyl)-D-serine 719.4 59    [00103]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-(((2-hydroxy-2-methylpropyl)amino) methyl)picolinamido)-2,2′-dimethyl- [1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 721.4 60    [00104]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((((1-hydroxycyclopropyl)methyl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 719.4 61    [00105]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((((1s,3s)-3-hydroxycyclobutyl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 719.4 62    [00106]embedded image ((4-cyclopropyl-6-((3′-(4-cyclopropyl- 5-((((1r,3r)-3-hydroxycyclobutyl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)-D-serine 719.4 63    [00107]embedded image ((6-((3′-(5-((((R)-1-carboxy-2- hydroxyethyl)amino)methyl)-4-cyclopropyl picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)-4-cyclopropyl pyridin-3-yl)methyl)-L-serine 737.4 64    [00108]embedded image (S)-2-(((6-((3′-(5-((((R)-2-carboxy-1- hydroxypropan-2-yl)amino)methyl)- 4-cyclopropylpicolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl)- 4-cyclopropylpyridin-3-yl)methyl) amino)-3-hydroxy-2-methylpropanoic acid 765.4 65    [00109]embedded image Ethyl ((4-cyclopropyl-6-((3′-(4- cyclopropyl-5-((((R)-1-ethoxy-3-hydroxy- 1-oxopropan-2-yl)amino)methyl) picolinamido)-2,2′-dimethyl-[1,1′- biphenyl]-3-yl)carbamoyl)pyridin-3-yl) methyl)-L-serinate 793.4 66    [00110]embedded image Ethyl (S)-2-(((4-cyclopropyl-6-((3′- (4-cyclopropyl-5-((((R)-1-ethoxy-3- hydroxy-2-methyl-1-oxopropan-2-yl) amino)methyl)picolinamido)-2,2′- dimethyl-[1,1′-biphenyl]-3-yl)carbamoyl) pyridin-3-yl)methyl)amino)-3-hydroxy- 2-methylpropanoate 821.4

    Example 67: Preparation of (2S,2′S)-2,2′-((((((2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(azanediyl))bis(carbonyl))bis(4-cyclopropylpyridine-6,3-diyl))bis(methylene))bis(azanediyl))bis(3-hydroxy-2-methylpropanoic acid)

    [0091] ##STR00111##

    Step 1: Synthesis of N,N′-(2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(4-cyclopropyl-5-(dimethoxymethyl)picolinamide)

    [0092] ##STR00112##

    [0093] Potassium 4-cyclopropyl-5-(dimethoxymethyl)picolinate (2.80 g, 10.1 mmol), HATU (3.54 g, 9.24 mmol), 2,2′-dimethyl-[1,1′-diphenyl]-3,3′-diamine (700 mg, 3.3 mmol) and DIPEA (2.5 mL) were weighed into a 100 mL eggplant-shaped flask, DMF/THF (20 mL, v/v=4/1) was added, and the mixture was stirred at room temperature for 6 hrs. The reaction solution was filtered and washed. The filtrate was concentrated and separated by silica gel column chromatography to obtain N,N′-(2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(4-cyclopropyl-5-(dimethoxymethyl)picolinamide) (1.30 g, yield: 61%). MS m/z (ESI): 651.6 [M+H].sup.+.

    Step 2: Synthesis of N,N′-(2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(4-cyclopropyl-5-formylpicolinamide)

    [0094] ##STR00113##

    [0095] N,N′-(2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(4-cyclopropyl-5-(dimethoxymethyl)picolinamide) (1300 mg, 2.0 mmol) was added with THF (20 mL), and then the reaction solution was added with a hydrochloric acid solution (8 mL, 4 M) and was stirred at room temperature for 4 hrs. After the reaction was completed, the reaction solution was added with water (8 mL) and stirred overnight. The reaction solution was filtrated and dried in vacuum to obtain N,N′-(2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(4-cyclopropyl-5-formylpicolinamide) (995 mg, yield: 90%). MS m/z (ESI): 559.2 [M+H].sup.+.

    Step 3: Synthesis of (2S,2′S)-2,2′-((((((2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(azanediyl))bis(carbonyl))bis(4-cyclopropylpyridine-6,3-diyl))bis(methylene))bis(azanediyl))bis(3-hydroxy-2-methylpropanoic acid)

    [0096] ##STR00114##

    [0097] N,N′-(2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(4-cyclopropyl-5-formylpicolinamide) (50 mg, 0.09 mmol) was added to DMF/CH.sub.2Cl.sub.2 (1.8 mL/0.9 mL), and then the reaction solution was added with DIPEA (116 mg, 0.90 mmol) and (S)-2-amino-3-hydroxy-2-methyl propanoic acid (107 mg, 0.90 mmol), stirred at room temperature for 6 hrs, then added with NaBH (OAc).sub.3 (190 mg, 0.90 mmol) and stirred at room temperature overnight. After the reaction was completed, the reaction solution was directly separated by reversed-phase column chromatography (eluent:water (0.1% TFA):acetonitrile), and lyophilized to obtain a TFA salt of (2S,2′S)-2,2′-((((((2,2′-dimethyl-[1,1′-biphenyl]-3,3′-diyl)bis(azanediyl))bis(carbonyl))bis(4-cyclopropylpyridine-6,3-diyl))bis(methylene))bis(azanediyl))bis(3-hydroxy-2-methylpropanoic acid) (17.2 mg, yield: 25%). MS m/z (ESI): 382.8 [½M+H].sup.+; 76 5.7 [M+H].sup.+.

    [0098] .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.38 (s, 2H), 8.74 (s, 2H), 7.80 (d, J=8.0 Hz, 2H), 7.67 (s, 2H), 7.34 (t, J=8.0 Hz, 2H). 7.01 (d, J=8.0 Hz, 2H), 4.54-4.46 (m, 4H), 3.97 (d, J=12.0 Hz, 2H), 3.84 (d, J=12.0 Hz, 2H), 2.43-2.36 (m, 4H), 2.00 (s, 6H), 1.56 (s, 6H), 1.24-1.16 (m, 4H), 0.96-0.91 (m, 4H).

    [0099] Examples 68 to 70 were prepared by selecting corresponding raw materials according to all or part of the synthesis method in Example 67.

    TABLE-US-00004 Ex- ample MS: m/z No. Structure Name [M + H].sup.+ 68 [00115]embedded image (2R,2′R)-2,2′-((((((2,2′-dimethyl-[1,1′- biphenyl]-3,3′-diyl)bis(azanediyl)) bis(carbonyl))bis(4-cyclopropylpyridine- 6,3-diyl))bis(methylene))bis(azanediyl)) bis(3-hydroxy-2-methylpropanoic acid 765.7 69 [00116]embedded image diethyl 2,2′-((((((2,2′-dimethyl-[1,1′- biphenyl]-3,3′-diyl)bis(azanediyl)) bis(carbonyl))bis(4-cyclopropylpyridine- 6,3-diyl))bis(methylene))bis(azanediyl)) (2S,2′S)-bis(3-hydroxy-2- methylpropanoate) 821.4 70 [00117]embedded image diethyl 2,2′-((((((2,2′-dimethyl-[1,1′- biphenyl]-3,3′-diyl)bis(azanediyl)) bis(carbonyl))bis(4-cyclopropylpyridine- 6,3-diyl))bis(methylene))bis(azanediyl)) (2R,2′R)-bis(3-hydroxy-2- methylpropanoate) 821.4

    [0100] .sup.1H NMR data of part of the compounds prepared in the above example are as follows:

    TABLE-US-00005 Example No. .sup.1H-NMR  2 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.33 (s, 1H), 10.32 (s, 1H), 8.63 (s, 1H), 8.52 (s, 1H), 7.88 (d, J = 7.6 Hz, 2H), 7.62 (s, 1H), 7.59 (s, 1H), 7.32 (t, J = 7.9 Hz, 2H), 6.99 (dd, J = 7.7, 3.0 Hz, 2H), 4.22-3.99 (m, 3H), 3.71 (d, J = 13.6 Hz, 1H), 3.25-3.15 (m, 2H), 2.90-2.80 (m, 2H), 2.48-2.43 (m, 2H), 2.34-2.21 (m, 2H), 2.01 (s, 6H), 1.83-1.72 (m, 2H), 1.56-1.38 (m, 4H), 1.21-1.00 (m, 7H), 0.97-0.73 (m, 4H).  3 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.58 (s, 1H), 8.52 (s, 1H), 7.88 (dd, J = 8.1, 3.9 Hz, 2H), 7.59 (d, J = 2.9 Hz, 2H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.03 (d, J = 13.8 Hz, 2H), 3.95 (d, J = 13.8 Hz, 1H), 3.70 (d, J = 13.9 Hz, 1H), 3.18 (t, J = 5.7 Hz, 2H), 2.90-2.81 (m, 2H), 2.75-2.65 (m, 2H), 2.33- 2.20 (m, 2H), 2.00 (s, 6H), 1.76 (s, 2H), 1.46 (brs, 4H), 1.12 (t, J = 8.5 Hz, 4H), 1.00 (d, J = 6.2 Hz, 3H), 0.94-0.74 (m, 4H).  4 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.60 (s, 1H), 8.52 (s, 1H), 7.88 (d, J = 8.0 Hz, 2H), 7.61 (s, 1H), 7.59 (s, 1H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.15-3.98 (m, 3H), 3.89 (s, 1H), 3.71 (d, J = 13.6 Hz, 1H), 3.19 (t, J = 5.6 Hz, 1H), 2.97-2.78 (m, 3H), 2.33-2.19 (m, 2H), 2.01 (s, 6H), 1.97-1.69 (m, 4H), 1.69-1.56 (m, 2H), 1.56-1.36 (m, 6H), 1.12 (t, J = 9.7 Hz, 4H), 0.95-0.72 (m, 4H).  6 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.58 (s, 1H), 8.51 (s, 1H), 7.88 (dd, J = 8.1, 5.2 Hz, 2H), 7.59 (s, 1H), 7.58 (s, 1H), 7.31 (t, J = 7.8 Hz, 2H), 6.97 (d, J = 7.5 Hz, 2H), 4.61 (s, 1H), 4.02 (d, J = 14.6 Hz, 3H), 3.84 (d, J = 3.6 Hz, 1H), 3.70 (d, J = 13.7 Hz, 2H), 3.19 (t, J = 5.7 Hz, 2H), 2.90-2.78 (m, 4H), 2.30-2.20 (m, 2H), 2.00 (s, 6H), 1.96-1.72 (m, 4H), 1.65-1.55 (m, 2H), 1.54-1.28 (m, 6H), 1.28- 1.16 (m, 9H), 1.15-1.06 (m, 4H), 0.95-0.74 (m, 4H).  7 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 1H), 10.31 (s, 1H), 8.58 (s, 1H), 8.51 (s, 1H), 7.86 (t, J = 8.7 Hz, 2H), 7.60 (s, 1H), 7.58 (s, 1H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (dd, J = 7.6, 3.5 Hz, 2H), 4.07 (s, 2H), 4.03 (d, J = 13.7 Hz, 1H), 3.70 (d, J = 13.7 Hz, 1H), 3.22-3.15 (m, 1H), 2.89-2.80 (m, 2H), 2.45 (s, 3H), 2.32-2.22 (m, 2H), 2.00 (s, 6H), 1.81-1.72 (m, 2H), 1.52-1.38 (m, 2H), 1.22-1.05 (m, 6H), 0.94- 0.72 (m, 4H).  8 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 1H), 10.31 (s, 1H), 8.60 (s, 1H), 8.51 (s, 1H), 7.86 (dd, J = 8.1, 4.6 Hz, 2H), 7.60 (s, 1H), 7.58 (s, 1H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (dd, J = 7.6, 3.4 Hz, 2H), 4.10 (s, 2H), 4.03 (d, J = 13.8 Hz, 1H), 3.70 (d, J = 13.7 Hz, 2H), 3.22-3.15 (m, 1H), 2.89-2.80 (m, 1H), 2.76 (q, J = 7.3 Hz, 2H), 2.47-2.42 (m, 1H), 2.34-2.20 (m, 2H), 2.00 (s, 6H), 1.81-1.73 (m, 2H), 1.52- 1.43 (m, 2H), 1.22-1.09 (m, 7H), 0.88 (t, J = 5.3 Hz, 4H).  9 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.34 (s, 1H), 10.31 (s, 1H), 8.67 (s, 1H), 8.51 (s, 1H), 7.85 (t, J = 8.8 Hz, 2H), 7.64 (s, 1H), 7.58 (s, 1H), 7.32 (td, J = 7.8, 3.4 Hz, 2H), 6.98 (t, J = 7.6 Hz, 2H), 4.25 (s, 2H), 4.03 (d, J = 13.7 Hz, 1H), 3.71 (d, J = 13.8 Hz, 2H), 3.23-3.15 (m, 2H), 2.89-2.79 (m, 2H), 2.48-2.40 (m, 1H), 2.34- 2.20 (m, 2H), 2.00 (s, 3H), 1.99 (s, 3H), 1.81-1.70 (m, 2H), 1.54-1.37 (m, 4H), 1.22 (d, J = 6.2 Hz, 6H), 1.22-1.07 (m, 4H), 0.96-0.71 (m, 4H). 10 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.35 (s, 1H), 10.31 (s, 1H), 8.71 (s, 1H), 8.52 (s, 1H), 7.87 (d, J = 8.0 Hz, 1H), 7.82 (d, J = 8.0 Hz, 1H), 7.64 (s, 1H), 7.59 (s, 1H), 7.32 (td, J = 7.8, 3.2 Hz, 2H), 6.99 (t, J = 8.4 Hz, 2H), 4.45 (s, 2H), 4.03 (d, J = 13.6 Hz, 1H), 3.72 (d, J = 13.8 Hz, 1H), 3.24-3.17 (m, 2H), 2.91-2.80 (m, 1H), 2.48- 2.42 (m, 1H), 2.35-2.20 (m, 2H), 2.00 (d, J = 3.8 Hz, 6H), 1.80-1.72 (m, 2H), 1.53-1.43 (m, 4H), 1.25-1.15 (m, 2H), 1.15-1.08 (m, 2H), 0.98-0.85 (m, 4H), 0.84-0.65 (m, 4H). 11 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.33 (s, 1H), 10.31 (s, 1H), 8.65 (s, 1H), 8.52 (s, 1H), 7.86 (t, J = 7.8 Hz, 2H), 7.63 (s, 1H), 7.59 (s, 1H), 7.32 (td, J = 7.8, 3.4 Hz, 2H), 6.98 (t, J = 7.4 Hz, 2H), 4.20 (brs, 2H), 4.03 (d, J = 13.8 Hz, 1H), 3.71 (d, J = 13.7 Hz, 1H), 3.20 (t, J = 5.5 Hz, 1H), 2.90-2.80 (m, 1H), 2.35-2.20 (m, 2H), 2.01 (s, 3H), 2.00 (s, 3H), 1.95-1.85 (m, 2H), 1.80-1.65 (m, 4H), 1.60-1.40 (m, 8H), 1.20-1.05 (m, 4H), 0.95-0.75 (m, 4H). 12 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.30 (s, 2H), 8.53 (s, 1H), 8.52 (s, 1H), 7.88 (d, J = 8.0 Hz, 2H), 7.59 (s, 2H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.03 (d, J = 13.7 Hz, 1H), 3.89 (brs, 2H), 3.71 (d, J = 13.8 Hz, 2H), 3.20 (t, J = 5.6 Hz, 1H), 2.90-2.81 (m, 1H), 2.56 (brs, 2H), 2.49-2.40 (m, 1H), 2.41-2.30 (m, 2H), 2.31-2.21 (m, 1H), 2.01 (s, 6H), 1.82-1.70 (m, 6H), 1.56-1.40 (m, 4H), 1.20- 1.07 (m, 4H), 0.91-0.74 (m, 4H). 13 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.52 (s, 2H), 7.88 (d, J = 8.4 Hz, 2H), 7.59 (s, 2H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.71 (brs, 1H), 4.21 (brs, 1H), 4.03 (d, J = 13.8 Hz, 1H), 3.86 (d, J = 13.4 Hz, 1H), 3.80 (d, J = 13.6 Hz, 1H), 3.70 (d, J = 13.7 Hz, 1H), 3.21-3.17 (m, 1H), 2.98-2.81 (m, 4H), 2.75 (dd, J = 9.5, 6.2 Hz, 1H), 2.42-2.30 (m, 2H), 2.31-2.20 (m, 2H), 2.01 (s, 6H), 1.82- 1.71 (m, 2H), 1.52-1.37 (m, 4H), 1.18-1.05 (m, 6H), 0.95-0.73 (m, 4H). 14 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.30 (s, 2H), 8.52 (s, 2H), 7.89 (d, J = 8.1 Hz, 2H), 7.59 (s, 1H), 7.58 (s, 1H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.4 Hz, 2H), 4.21 (tt, J = 7.0, 3.5 Hz, 1H), 4.05 (d, J = 13.5 Hz, 1H), 3.86 (d, J = 13.5 Hz, 1H), 3.80 (d, J = 13.6 Hz, 1H), 3.67 (d, J = 14.0 Hz, 1H), 3.13 (brs, 2H), 3.00-2.80 (m, 2H), 2.75 (dd, J = 9.6, 6.2 Hz, 1H), 2.70-2.62 (m, 1H), 2.43-2.30 (m, 3H), 2.22 (brs, 1H), 2.05-1.95 (m, 1H), 2.01 (s, 6H), 1.80-1.70 (m, 2H), 1.63-1.32 (m, 6H), 1.20- 1.07 (m, 4H), 0.90-0.70 (m, 4H). 15 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.52 (s, 2H), 7.86 (t, J = 8.3 Hz, 2H), 7.60 (s, 1H), 7.59 (s, 1H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (dd, J = 7.7, 3.4 Hz, 2H), 4.03 (d, J = 13.8 Hz, 2H), 3.71 (d, J = 13.7 Hz, 2H), 3.20 (t, J = 5.6 Hz, 4H), 2.90-2.81 (m, 2H), 2.45 (d, J = 7.6 Hz, 1H), 2.32-2.20 (m, 2H), 2.00 (s, 6H), 1.82- 1.72 (m, 2H), 1.53-1.43 (m, 4H), 1.40 (s, 3H), 1.20-1.07 (m, 4H), 0.95-0.73 (m, 4H). 23 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.34 (s, 1H), 10.31 (s, 1H), 8.65 (s, 1H), 8.52 (s, 1H), 7.85 (dd, J = 12.7, 8.1 Hz, 2H), 7.61 (s, 1H), 7.58 (s, 1H), 7.32 (td, J = 7.8, 2.8 Hz, 2H), 6.98 (t, J = 7.4 Hz, 2H), 4.70 (t, J = 7.1 Hz, 2H), 4.54 (brs, 2H), 4.23 (brs, 2H), 4.05 (d, J = 13.6 Hz, 1H), 3.74 (d, J = 12.9 Hz, 1H), 2.90-2.80 (m, 2H), 2.48- 2.38 (m, 1H), 2.38-2.21 (m, 2H), 2.00 (d, J = 2.7 Hz, 6H), 1.83-1.71 (m, 2H), 1.56-1.38 (m, 4H), 1.23-1.08 (m, 4H), 0.98-0.73 (m, 4H). 24 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.33 (s, 1H), 10.31 (s, 1H), 8.66 (s, 1H), 8.51 (s, 1H), 7.86 (t, J = 6.9 Hz, 2H), 7.63 (s, 1H), 7.58 (s, 1H), 7.32 (td, J = 7.9, 2.8 Hz, 2H), 6.98 (t, J = 6.8 Hz, 2H), 4.22 (brs, 2H), 4.03 (d, J = 13.7 Hz, 1H), 3.90 (d, J = 11.7 Hz, 2H), 3.71 (d, J = 13.7 Hz, 1H), 3.19 (t, J = 5.7 Hz, 2H), 2.89-2.80 (m, 2H), 2.48-2.40 (m, 2H), 2.35-2.20 (m, 2H), 2.00 (d, J = 2.4 Hz, 6H), 1.98-1.90 (m, 2H), 1.80-1.70 (m, 2H), 1.55-1.34 (m, 4H), 1.20-1.05 (m, 4H), 0.96-0.70 (m, 4H). 25 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.57 (s, 1H), 8.52 (s, 1H), 7.89 (dd, J = 8.1, 4.7 Hz, 2H), 7.59 (s, 1H), 7.58 (s, 1H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.04 (d, J = 13.7 Hz, 1H), 3.96 (d, J = 13.8 Hz, 1H), 3.91 (d, J = 13.8 Hz, 1H), 3.82-3.63 (m, 5H), 3.52-3.44 (m, 2H), 3.16 (t, J = 5.7 Hz, 1H), 2.89- 2.80 (m, 1H), 2.34-2.19 (m, 2H), 2.00 (s, 6H), 2.00-1.92 (m, 1H), 1.81-1.70 (m, 3H), 1.54-1.36 (m, 4H), 1.18-1.07 (m, 4H), 0.94-0.74 (m, 4H). 27 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.30 (s, 2H), 8.54 (s, 1H), 8.52 (s, 1H), 7.89 (t, J = 8.7 Hz, 2H), 7.59 (s, 1H), 7.58 (s, 1H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 1.5 Hz, 2H), 4.34 (d, J = 13.4 Hz, 1H), 4.03 (d, J = 13.7 Hz, 1H), 3.70 (d, J = 13.5 Hz, 1H), 3.61 (d, J = 13.4 Hz, 1H), 3.50-3.40 (m, 2H), 3.20-3.15 (m, 1H), 2.91-2.81 (m, 1H), 2.81-2.62 (m, 4H), 2.30-2.20 (m, 2H), 2.01 (s, 6H), 1.93-1.82 (m, 1H), 1.80-1.75 (m, 1H), 1.70-1.55 (m, 4H), 1.50-1.35 (m, 4H), 1.15-1.00 (m, 4H), 0.99 0.84 (m, 2H), 0.84-0.70 (m, 2H). 28 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.30 (s, 2H), 8.54 (s, 1H), 8.52 (s, 1H), 7.89 (t, J = 8.3 Hz, 2H), 7.59 (s, 1H), 7.58 (s, 1H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.35 (d, J = 13.4 Hz, 1H), 4.03 (d, J = 13.7 Hz, 1H), 3.71 (d, J = 13.6 Hz, 1H), 3.67-3.55 (m, 1H), 3.50-3.40 (m, 1H), 3.23-3.06 (m, 3H), 2.91-2.75 (m, 2H), 2.47-2.37 (m, 2H), 2.35-2.20 (m, 2H), 2.00 (s, 6H), 1.94-1.81 (m, 1H), 1.80- 1.74 (m, 1H), 1.71-1.54 (m, 2H), 1.50-1.35 (m, 4H), 1.17-1.05 (m, 4H), 0.99- 0.84 (m, 2H), 0.82-0.72 (m, 2H). 31 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 1H), 10.30 (s, 1H), 8.55 (s, 1H), 8.52 (s, 1H), 7.93-7.84 (m, 2H), 7.59 (s, 2H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.7 Hz, 2H), 4.11 (q, J = 7.6 Hz, 2H), 4.03 (d, J = 13.6 Hz, 2H), 3.72 (d, J = 13.7 Hz, 1H), 3.62 (brs, 2H), 2.90-2.82 (m, 2H), 2.68-2.65 (m, 1H), 2.35-2.23 (m, 3H), 2.01 (s, 3H), 2.00 (s, 3H), 1.82-1.72 (m, 2H), 1.55-1.40 (m, 4H), 1.20 (t, J = 7.1 Hz, 3H), 1.15-1.07 (m, 4H), 0.95-0.75 (m, 4H). 32 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.35 (s, 1H), 10.32 (s, 1H), 8.74 (s, 1H), 8.54 (s, 1H), 7.87 (d, J = 8.0 Hz, 1H), 7.83 (d, J = 8.0 Hz, 1H), 7.64 (s, 1H), 7.60 (s, 1H), 7.33 (t, J = 7.7 Hz, 2H), 6.99 (t, J = 7.1 Hz, 2H), 4.38 (brs, 2H), 4.07 (d, J = 13.7 Hz, 1H), 4.00-3.82 (m, 2H), 3.76 (d, J = 13.8 Hz, 1H), 2.90-2.80 (m, 1H), 2.41-2.26 (m, 2H), 2.01 (s, 3H), 2.00 (s, 3H), 1.86-1.74 (m, 2H), 1.57-1.37 (m, 4H), 1.21- 1.08 (m, 4H), 0.98-0.73 (m, 4H). 37-1 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.58 (s, 1H), 8.54 (s, 1H), 7.88 (d, J = 8.1 Hz, 2H), 7.60 (s, 1H), 7.59 (s, 1H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 3H), 4.85 (t, J = 5.9 Hz, 1H), 4.58 (brs, 1H), 4.10 (q, J = 7.2 Hz, 2H), 4.06 (d, J = 13.6 Hz, 1H), 4.03 (s, 2H), 3.90 (d, J = 13.7 Hz, 1H), 3.61 (t, J = 5.3 Hz, 2H), 3.52 (t, J = 5.3 Hz, 2H), 3.37-3.33 (m, 1H), 2.70 (t, J = 5.7 Hz, 2H), 2.37-2.23 (m, 2H), 2.00 (s, 6H), 1.20 (t, J = 7.1 Hz, 3H), 1.18-1.06 (m, 4H), 0.90-0.78 (m, 4H). 37 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 1H), 10.31 (s, 1H), 8.582 (s, 1H), 8.577 (s, 1H), 7.88 (dd, J = 8.1, 4.4 Hz, 2H), 7.60 (s, 2H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.14 (d, J = 13.7 Hz, 1H), 4.02 (s, 2H), 3.98 (d, J = 13.8 Hz, 1H), 3.64 (t, J = 5.0 Hz, 2H), 3.52 (t, J = 5.7 Hz, 2H), 3.28-3.21 (m, 1H), 2.74-2.65 (m, 2H), 2.35-2.24 (m, 2H), 2.00 (s, 6H), 1.21-1.08 (m, 4H), 0.94-0.81 (m, 4H). 38-1 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 1H), 10.31 (s, 1H), 8.62 (s, 1H), 8.54 (s, 1H), 7.86 (dd, J = 8.1, 3.4 Hz, 2H), 7.61 (s, 1H), 7.58 (s, 1H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (dd, J = 7.5, 3.1 Hz, 2H), 4.20-4.01 (m, 5H), 3.90 (d, J = 13.7 Hz, 1H), 3.61 (t, J = 4.7 Hz, 2H), 2.95-2.85 (s, 1H), 2.34-2.23 (m, 2H), 2.00 (s, 6H), 1.19 (t, J = 7.1 Hz, 3H), 1.18-1.08 (m, 4H), 1.09 (d, J = 6.5 Hz, 3H), 0.92-0.81 (m, 4H). 38 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 2H), 8.60 (s, 1H), 8.59 (s, 1H), 7.88 (t, J = 6.6 Hz, 2H), 7.60 (s, 2H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.15 (d, J = 13.7 Hz, 1H), 4.08 (d, J = 13.7 Hz, 1H), 4.00 (dd, J = 13.8, 4.3 Hz, 2H), 3.65 (t, J = 5.6 Hz, 2H), 3.40-3.20 (m, 3H), 2.77 (q, J = 6.2 Hz, 1H), 2.38-2.23 (m, 2H), 2.00 (s, 6H), 1.13 (d, J = 8.4 Hz, 4H), 1.03 (d, J = 6.3 Hz, 3H), 0.90 0.80 (m, 4H). 39-1 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.59 (s, 1H), 8.54 (s, 1H), 7.89 (dd, J = 8.3, 3.6 Hz, 2H), 7.60 (s, 1H), 7.59 (s, 1H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.14-4.02 (m, 4H), 3.97 (d, J = 13.8 Hz, 1H), 3.90 (d, J = 13.7 Hz, 1H), 3.62 (d, J = 4.9 Hz, 2H), 3.39-3.33 (m, 3H), 2.77-2.67 (m, 1H), 2.34-2.23 (m, 2H), 2.01 (s, 6H), 1.20 (t, J = 7.1 Hz, 3H), 1.17-1.08 (m, 4H), 1.01 (d, J = 6.4 Hz, 3H), 0.91-0.78 (m, 4H). 39 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 1H), 10.31 (s, 1H), 8.59 (s, 2H), 7.88 (t, J = 7.8 Hz, 2H), 7.60 (s, 2H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.14 (d, J = 13.8 Hz, 1H), 4.05 (d, J = 13.8 Hz, 1H), 3.98 (dd, J = 13.8, 4.2 Hz, 2H), 3.68- 3.59 (m, 2H), 3.39-3.28 (m, 2H), 3.25 (t, J = 5.1 Hz, 1H), 2.80-2.65 (m, 1H), 2.39-2.24 (m, 2H), 2.00 (s, 6H), 1.13 (d, J = 8.5 Hz, 4H), 1.01 (d, J = 6.3 Hz, 3H), 0.95-0.80 (m, 4H). 40 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 1H), 10.30 (s, 1H), 8.58 (s, 1H), 8.57 (s, 1H), 7.87 (t, J = 8.8 Hz, 2H), 7.59 (s, 2H), 7.31 (t, J = 7.8 Hz, 2H), 6.97 (d, J = 7.6 Hz, 2H), 4.11 (d, J = 13.8 Hz, 1H), 3.97 (brs, 3H), 3.82 (q, J = 5.1 Hz, 1H), 3.70- 3.55 (m, 2H), 3.12-3.04 (m, 1H), 2.82 (q, J = 5.7 Hz, 1H), 2.38-2.22 (m, 2H), 2.00 (s, 6H), 1.90-1.75 (m, 2H), 1.65-1.50 (m, 2H), 1.46-1.25 (m, 2H), 1.18- 1.05 (m, 4H), 0.90-0.80 (m, 4H). 51 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 1H), 10.30 (s, 1H), 8.58 (s, 2H), 7.88 (t, J = 8.5 Hz, 2H), 7.59 (s, 2H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.14 (d, J = 13.8 Hz, 1H), 4.00-3.94 (m, 3H), 3.84 (dt, J = 11.6, 3.6 Hz, 2H), 3.68-3.58 (m, 2H), 3.30-3.20 (m, 3H), 2.73-2.64 (m, 1H), 2.36-2.25 (m, 2H), 2.00 (s, 6H), 1.84 (d, J = 11.9 Hz, 2H), 1.40-1.26 (m, 2H), 1.19-1.08 (m, 4H), 0.90-0.81 (m, 4H). 53-1 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 2H), 8.54 (s, 2H), 7.88 (d, J = 8.0 Hz, 2H), 7.59 (s, 2H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.85 (t, J = 5.8 Hz, 1H), 4.71 (brs, 1H), 4.23 (brs, 1H), 4.10 (q, J = 7.0 Hz, 2H), 4.06 (d, J = 13.6 Hz, 1H), 3.90 (d, J = 13.7 Hz, 1H), 3.84 (brs, 1H), 3.61 (t, J = 5.4 Hz, 2H), 3.39-3.32 (m, 1H), 2.85-2.65 (m, 2H), 2.39-2.24 (m, 2H), 2.10-1.95 (m, 1H), 2.01 (s, 6H), 1.65-1.52 (m, 1H), 1.20 (t, J = 7.1 Hz, 3H), 1.19-1.07 (m, 4H), 0.90-0.78 (m, 4H). 53 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.31 (s, 1H), 10.30 (s, 1H), 8.58 (s, 1H), 8.52 (s, 1H), 7.88 (t, J = 7.0 Hz, 2H), 7.60 (s, 1H), 7.59 (s, 1H), 7.31 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.26-4.16 (m, 1H), 4.14 (d, J = 13.8 Hz, 1H), 3.98 (d, J = 13.7 Hz, 1H), 3.86 (d, J = 13.6 Hz, 1H), 3.80 (d, J = 13.5 Hz, 1H), 3.68-3.58 (m, 2H), 2.75 (dd, J = 9.6, 6.1 Hz, 1H), 2.66 (q, J = 7.8 Hz, 1H), 2.39 (dd, J = 9.6, 3.5 Hz, 1H), 2.39-2.26 (m, 2H), 2.00 (s, 6H), 2.06-1.94 (m, 1H), 1.63-1.50 (m, 1H), 1.18-1.04 (m, 4H), 0.90-0.80 (m, 4H). 54 .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 10.32 (s, 1H), 10.30 (s, 1H), 8.58 (s, 1H), 8.54 (s, 1H), 7.89 (dd, J = 11.8, 8.1 Hz, 2H), 7.59 (s, 1H), 7.58 (s, 1H), 7.32 (t, J = 7.8 Hz, 2H), 6.98 (d, J = 7.5 Hz, 2H), 4.34 (d, J = 13.3 Hz, 1H), 4.11 (d, J = 13.8 Hz, 1H), 3.96 (d, J = 13.8 Hz, 1H), 3.70-3.55 (m), 3.34-3.27 (m), 3.05 (t, J = 6.0 Hz, 1H), 2.77 (t, J = 7.8 Hz, 1H), 2.70-2.62 (m, 1H), 2.49-2.40 (m, 1H), 2.36-2.23 (m, 2H), 2.01 (s, 6H), 1.93-1.82 (m, 1H), 1.70-1.52 (m, 3H), 1.20-1.06 (m, 4H), 0.99-0.71 (m, 4H).

    Biological Test Evaluation

    1. PD1-PDL1 HTRF Binding Activity Test

    [0101] The effect of compounds of the examples of the present invention on the interaction between PD-1 and PD-L1 was determined by the PD-1/PD-L1 binding assay kit from Cisbio (#64ICP01PEG or 64ICP01PEH). The detailed experimental process was as follows:

    [0102] 1) Pre-diluted compound solution, 4 μL of Tag1-PD-L1 and 4 μL of Tag2-PD1 were added to each well of a 384-well plate;

    [0103] 2) After the mixture was incubated at room temperature for 15 min, 5 μL of anti-Tag1-Eu3+ antibody and 5 μL of anti-Tag2-XL665 antibody were then added;

    [0104] 3) After incubated for 2 hrs at room temperature or overnight at 4° C., plates were read on Envision of Perkin Elmer; and readings at 665 nm and 620 nm were recorded, and the ratio of the two readings was taken as a reading for each well;

    [0105] 4) The reading of each well after compound treatment was compared with the reading of DMSO treated wells to obtain the percent inhibition of the compound; and

    [0106] 5) IC.sub.50 values of compounds of the examples of the present invention were determined by non-linear regression analysis of percent inhibition at different compound concentrations. The specific experimental results were shown in Table 1.

    2. Jurkat Reporter Gene Cellular Assay

    [0107] The effect of compounds of the examples of the present invention on the interaction between PD-1 and PD-L1 expressed on cell surfaces, and the related influence on T cell functions, were determined by a Jurkat reporter gene cellular assay.

    [0108] Briefly, the reporter gene plasmid of NF-κB-luc and the plasmid of human PD-1 were transfected into Jurkat cells to establish a stably transfected cell line capable of stably expressing both PD-1 and NF-κB-Luc reporter genes; the expression level of PD-1 on the cell surface was confirmed by flow cytometry; and the expression of the reporter gene was confirmed via the response of the reporter gene stimulated by OKT-3 and Raji cells.

    [0109] In addition, the plasmid of human PD-L1 was transfected into Raji cells to obtain a cell line capable of stably expressing PD-L1. Jurkat/NF-κB-luc/PD1 cells and Raji-PD-L1 cells were then cocultured and stimulated with OKT-3. On this basis, the compounds were added, and the enhancement of the signal pathway of T cell activation by the inhibitory effect of the compounds on the interaction between PD-1 and PD-L1 was evaluated by readings of reporter gene responses. The specific experimental process was as follows:

    [0110] 1) 30 μL of compound or antibody solution was added to each well of a white 96-well plate (Corning, 3610) at different diluted concentrations, and 10 μL of OKT3 (Biolegend, 317326) was then added (the final concentration of OKT3: 1 μg/mL);

    [0111] 2) 20 μL of Raji-PD-L1 cell suspension was added to each well with 5*10.sup.4 cells for each well, and was incubated in an incubator for 20 min;

    [0112] 3) 20 μL of Jurkat/NF-Kb-luc/PD-1 cell suspension was added to each well with 5*10.sup.4 cells for each well, and was well mixed, and 6 hrs later, Bright-glo (Promega, E2620) was applied and plates were read on Envision;

    [0113] 4) The reading of each well treated with the compound was compared with the reading of each well treated with DMSO to obtain the activation fold of the compound; and

    [0114] 5) EC.sub.50 values of compounds of the examples of the present invention were determined by non-linear regression analysis of activation folds at different compound concentrations. The specific experimental results were shown in Table 1:

    TABLE-US-00006 TABLE 1 Biological Test Results PD1-PDL1 HTRF Example Binding Activity Cell Activity No. IC.sub.50/nM EC.sub.50/nM  1 1.07 6.8  2 1.21 9.2  3 1.07 14.9  4 1.02 3.2  5 NT NT  6 1.69 49.3  7 0.49 24.1  8 1.27 23.8  9 5.10 33.9 10 3.38 119.5 11 3.19 14.5 12 1.02 10.6 13 1.48 11.8 14 1.76 8.2 15 0.68 15.1 16 NT NT 17 NT NT 18 NT NT 19 NT NT 20 NT NT 21 NT NT 22 NT NT 23 2.57 77.5 24 0.91 52.0 25 0.91 8.7 26 NT NT 27 2.62 27.3 28 4.17 35.3 29 1.61 115.2 30 0.97 18.1 31 2.57 42.6 32 1.85 44.8 33 NT NT 34 NT NT 35-1 3.03 231.4 35 1.95 28.6 36-1 64.3 NT 36 0.72 52 37-1 5.58 265.2 37 0.95 25.2 38-1 4.77 219.4 38 0.67 37.3 39-1 3.22 264.2 39 1.89 36.0 40 1.68 39.2 41 NT NT 42 NT NT 43 NT NT 44 NT NT 45 NT NT 46 NT NT 47 NT NT 48 NT NT 49 NT NT 50 NT NT 51 2.05 87.1 52 NT NT 53-1 5.77 258.5 53 3.61 86.8 54 0.91 62.3 55 3.18 99.5 56 NT NT 57 NT NT 58 NT NT 59 NT NT 60 NT NT 61 NT NT 62 NT NT 63 NT NT 64 NT NT 65 NT NT 66 NT NT 67 0.61 19.7 68 NT NT 69 NT NT 70 NT NT Notes ″NT″ is an abbreviation of ″Not Tested″, and means that an object has not been detected yet.

    [0115] The bioactivity data of the compounds of the specific examples indicates that the series of compounds of the present invention have a strong inhibitory effect on the interaction between PD-1 and PD-L1, and moreover, such an inhibitory effect can enhance or recover the activation of T cells at the cellular level.

    [0116] All documents mentioned in the present invention are incorporated as references, just as each document is individually cited as a reference. In addition, it should be understood that various modifications or changes may be made by those skilled in the art after reading the above teachings of the present invention, and these equivalent forms also fall within the scope defined by the claims appended hereto.