Receptor inhibitor, pharmaceutical composition comprising same, and use thereof

A compound or a pharmaceutically acceptable salt, stereoisomer, or N-oxide thereof, wherein the compound has a structure of formula (IV):

• wherein:
• U is C1-3 alkylene;
• R1a is selected from the group consisting of C2-8 alkenyl and C2-8 alkynyl, each of which is substituted by one C6-10 aryl or 5- to 14-membered heteroaryl;
• C6-10 aryl;
• —C1-6 alkylene-saturated or partially unsaturated C3-10 cyclic hydrocarbyl group;
• —C1-6 alkylene-saturated or partially unsaturated 3- to 10-membered heterocyclic group;
• —C1-6 alkylene-C6-10 aryl;
• and —C1-6 alkylene-(5- to 14-membered heteroaryl);
• R1b does not exist, or is selected from the group consisting of H, C1-8 alkyl optionally substituted by 1, 2, 3 or more R13;
• a saturated or partially unsaturated C3-10 cyclic hydrocarbyl group;
• C6-10 aryl;
• —C1-6 alkylene-saturated or partially unsaturated C3-10 cyclic hydrocarbyl group;
• and —C1-6 alkylene-C6-10 aryl;
• X1 does not exist, or is CR10 or N;
• X4 is selected from the group consisting of C(═O);
• and —OC(═O)— and —SC(═O)—, wherein O and S are connected to X1;
• R2a is C6-10 aryl;
• R2b is C6-10 aryl;
• X2 is CR10 or N;
• R3 is —C(═O)R11;
• R4 is H;
• R10, at each occurrence, is selected from the group consisting of H, —OR11, —SR11, and C1-6 alkyl;
• R11 and R12, at each occurrence, are each independently H, or C1-6 alkyl;
• h and k are each independently 1;
• the above alkylene, cyclic hydrocarbyl group, heterocyclic group, aryl, and heteroaryl, at each occurrence, are each optionally substituted by 1, 2, 3 or more R13;
• wherein the R13, at each occurrence, is independently selected from the group consisting of halogen, cyano, nitro, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cyclic hydrocarbyl group, C6-10 aryl, 5- to 14-membered heteroaryl, —OR1, —SR11, —P(O)R11R12, and —NR11R12, and wherein the alkyl, alkylene, aryl, and heteroaryl recited for the substituent R13 are optionally further substituted by 1, 2, 3 or more substituents independently selected from halogen and C1-6 alkyl.