Pyrimidine-4,6-diamine derivative, a preparation method therefor, and a pharmaceutical application thereof

A compound of formula (III), or a stereoisomer or pharmaceutically acceptable salt thereof:

• wherein, X1 and X2 are each independently N or CH;
• Y is a bond, O, S, N(R14), or C(R15R16);
• R1 is selected from the group consisting of hydrogen, deuterium, halogen, cyano, methyl, ethyl, isopropyl, allyl, vinyl, ethynyl, cyclopropyl, cyclobutyl, morpholinyl, 3-6 membered oxacyclyl, 3-6 membered azacyclyl, hydroxy, methoxy, ethoxy, isopropoxy, cyclopropyloxy, cyclobutyloxy, and 3-6 membered heterocyclyloxy, each of the above R1 groups independently optionally further substituted with one or more substituents selected from the group consisting of deuterium, fluoro, chloro, bromo, hydroxy, cyano, C1-4 alkyl, C3-6 cycloalkyl, 3-6 membered heterocyclyl, amino, monoC1-4 alkylamino, and diC1-4 alkylamino;
• R2 is selected from the group consisting of hydrogen, deuterium, fluoro, chloro, bromo, cyano, methyl, ethyl, propyl, isopropyl, cyclopropyl, cyclobutyl, cyclopentyl, azacyclobutyl, pyrazolyl, imidazolyl, oxazolyl, and triazolyl, each of the above R2 groups independently optionally further substituted with one or more substituents selected from the group consisting of deuterium;
• fluoro, chloro, bromo, cyano, methyl, ethyl, C1-4 haloalkyl, C1-4 deuterioalkyl, C2-4 alkenyl, C2-4 alkynyl, C3-6 cycloalkyl, and 3-6 membered heterocyclyl;
• R5a is selected from the group consisting of hydrogen, deuterium, fluoro, chloro, bromo, cyano, C1-4 alkyl, C1-4 haloalkyl, C1-4 deuterioalkyl, and C3-6 cycloalkyl;
• R5e is selected from the group consisting of hydrogen, deuterium, fluoro, chloro, bromo, cyano, C1-4 alkyl, C1-4 haloalkyl, C1-4 deuterioalkyl, and C3-6 cycloalkyl;
• R14 is selected from the group consisting of hydrogen, deuterium, hydroxy, methyl, ethyl, propyl, isopropyl, C1-4 haloalkyl, C1-4 deuterioalkyl, C3-6 cycloalkyl, 3-6 membered heterocyclyl, —S(O)rR8, —C0-4 alkyl-O—R9, —C(O)OR9, —C(O)R10, and —C(O)NR11R12;
• and
• R15 and R16 are each independently selected from the group consisting of hydrogen, deuterium, fluoro, chloro, bromo, cyano, C1-4 alkyl, C2-4 alkenyl, C2-4 alkynyl, C3-6 cycloalkyl, and 3-6 membered heterocyclyl, or R15 and R16, together with the carbon atom to which R15 and R16 are directly attached, form a C(O), C3-6 cycloalkyl, or 3-6 membered heterocyclyl, each of the above R15 and R16 groups optionally further substituted with one or more substituents selected from the group consisting of deuterium, fluoro, chloro, bromo, cyano, C1-4 alkyl, C1-4 haloalkyl, C1-4 deuterioalkyl, C2-4 alkenyl, C2-4 alkynyl, C3-6 cycloalkyl, 3-6 membered heterocyclyl, and ═O.