A compound of formula (I), or a tautomer, mesomer, cluster, enantiomer, diastereomer and mixtures thereof, and a pharmaceutically acceptable salt thereof: in which: A is CH or N； L is a C1-12 alkyl or bond； R1 is selected from the group consisting of hydrogen, C1-12 alkyl, C3-6 cycloalkyl, heterocyclyl, C6-10 aryl, heteroaryl, - (CH2) nC (O) OR15, -OC (O) R15, -C (O ) R15, -C (O) NR16R17, -NHC (O) R15, -NR16R17, -OC (O) NR16R17, - NHC (O) NR16R17 and -S (O) mR15, in which C1-12 alkyl, C3-6 cycloalkyl, heterocyclyl, C6-10 aryl or heteroaryl are each optionally substituted with one or more groups selected from the group consisting of halogen, hydroxy, cyano, nitro, C1-12 alkyl, C1-12 alkoxy, C3 cycloalkyl -6, heterocyclyl, C6-10 aryl, heteroaryl, - (CH2) nC (O) OR15, -OC (O) R15 and -C (O) R15； R2 is C1-12 alkyl； R4 is hydrogen； R is selected from the group consisting of hydrogen and halogen； R3 is selected from the group consisting of hydrogen, halogen and C1-12 alkyl； R5 or R6 is each independently hydrogen； R7 or R8 is each independently hydrogen； R9 or R10 is hydrogen； R11, R12, R13 or R14 is each hydrogen； or R11 and R12 or R13 and R14 are taken together to form an oxo group； R15 is selected from the group consisting of hydrogen, C1-12 alkyl, C3-6 cycloalkyl, heterocyclyl, alkenyl, alkynyl, C6-10 aryl and heteroaryl, wherein C1-12 alkyl, C3-6 cycloalkyl, heterocyclyl, aryl C6-10 or heteroaryl is each optionally substituted with one or more groups selected from the group consisting of C1-12 alkyl, halogen, hydroxy, cyano, amino, nitro, C1-12 alkoxy, C3-6 cycloalkyl, heterocyclyl, aryl C6-10, heteroaryl, - (CH2) nC (O) OR18, -OC (O) R18, -C (O) R18, -NHC (O) R18, -S (O) mR18, -NHC (O) OR18 and - NHS (O) mR18； R16 or R17 is each independently selected from the group consisting of hydrogen, C1-12 alkyl, C3-6 cycloalkyl and heteroaryl, wherein C1-12 alkyl, C3-6 cycloalkyl or heteroaryl is each optionally substituted with one or more groups selected from the group cons
