Pyrazolopyrimidine compound used as ATR kinase inhibitor

A compound of general formula (I), or a pharmaceutically acceptable salt, enantiomer, diastereomer, racemate, solvate, hydrate, polymorph, prodrug, or isotopic variant thereof, or a mixture thereof:

• wherein
• X is CRX or N;
• Y is CRY or N;
• R1, R2, R3, R4 and RY are independently selected from H, D, halogen, C1-6 alkyl, C2-6 alkenyl and C2-6 alkynyl, or R1 and R2, R3 and R4 are connected to form bond, C1-6 alkylene, C2-6 alkenylene or C2-6 alkynylene;
• wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• wherein RX is H, D, halogen, —CN, —NRR′, —OR, —SR or C1-6 alkyl, wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• when Y is CRY, RY and R1 are taken together with the atoms to which they are attached to form C3-5 cycloalkyl or 3- to 5-membered heterocyclyl, wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• ring A is C3-7 cycloalkyl, 4- to 7-membered heterocyclyl, C6-10 aryl or 5- to 10-membered heteroaryl;
• Ra is independently selected from H, D, halogen, —CN, —NRR′, —OR, —SR, —C(O)R, —C(O)OR, —C(O)NRR′, —OC(O)R′, —NRC(O)R′, —OC(O)NRR′, —NRC(O)NRR′, —S(O)pR, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C3-7 cycloalkyl and 3- to 8-membered heterocyclyl, each of which is optionally substituted with R*, wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• m is 0, 1, 2, 3, 4 or 5;
• ring B is 5- to 6-membered heteroaryl;
• Rb is independently selected from H, D, halogen, —CN, —NRR′, —OR, —SR, —C(O)R, —C(O)OR, —C(O)NRR′, —OC(O)R′, —NRC(O)R′, —OC(O)NRR′, —NRC(O)NRR′, —S(O)pR, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C3-7 cycloalkyl and 3- to 8-membered heterocyclyl, each of which is optionally substituted with R*, wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• n is 0, 1, 2, 3, 4 or 5;
• ring C is C3-7 cycloalkyl, 4- to 7-membered heterocyclyl, C6-10 aryl or 5- to 10-membered heteroaryl;
• L is a bond, —O—, —S—, —N(R)—, —C(O)—, C1-6 alkylene, C2-6 alkenylene or C2-6 alkynylene;
• R5 is H, D, halogen, —CN, —NRR′, —OR, —SR, C1-6 alkyl, C2-6 alkenyl or C2-6 alkynyl, wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• R6 is H, D, halogen, —CN, —NRR′, —OR, —SR, C1-6 alkyl, C2-6 alkenyl or C2-6 alkynyl, wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• R* is H, halogen, —CN, —NRR′, —OR, —SR, —C(O)R, —C(O) OR, —C(O)NRR′, —OC(O)R′, —NRC(O)R′, —OC(O)NRR′, —NRC(O)NRR′, —S(O)pR, C3-7 cycloalkyl, 3- to 8-membered heterocyclyl, C6-10 aryl or 5- to 10-membered heteroaryl, wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• R and R′ are independently selected from H, C1-6 alkyl, C2-6 alkenyl and C2-6 alkynyl, or R and R′ are taken together with the nitrogen atom to which they are attached to form 4- to 8-membered heterocyclyl;
• wherein the groups may be substituted by one or more D or halogens up to fully substituted;
• p is 1 or 2.