A compound represented by Formula (IV), or a stereoisomer, a geometric isomer, a tautomer or a pharmaceutically acceptable salt thereof: wherein, R 1 is methyl; L is selected from a single bond or C 1-3 alkylene; preferably, L is selected from a single bond or -CH 2 -; R 2 is selected from 3- to 7-membered cycloalkyl, or 3- to 7-membered heterocycloalkyl, R 2 is optionally substituted with m Rb; m is 0, 1, 2, 3 or 4; each Rb is independently selected from halogen, cyano, hydroxyl, trifluoromethyl, C 1-3 alkyl, C 1-3 alkoxy, C 1-3 hydroxyalkyl, C 1-3 alkylamino or di(C 1-3 alkyl)amino; preferably, Rb is independently selected from F or methyl; R 3 is selected from C 1-3 alkoxy, halogen or C 1-3 alkyl; preferably, R 3 is selected from methoxy, chloro or methyl; R 4 is selected from C 1-3 alkyl, 3- to 7-membered cycloalkyl, 6- to 10-membered aryl or 5- to 6-membered heteroaryl, wherein said 6- to 10-membered aryl and 5- to 6-membered heteroaryl are optionally substituted with one or more groups independently selected from hydrogen, halogen, C 1-3 alkyl, amino, C 1-3 alkylamino, di(C 1-3 alkyl)amino, trifluoromethyl, difluoromethyl, cyano or C 1-3 alkoxy; preferably, R 4 is selected from C 1-3 alkyl, 3- to 7-membered cycloalkyl, phenyl or thienyl, wherein said phenyl or thienyl are optionally substituted with one or more groups independently selected from hydrogen, halogen, C 1-3 alkyl, amino, C 1-3 alkylamino, di(C 1-3 alkyl)amino, trifluoromethyl, difluoromethyl, cyano or C 1-3 alkoxy; futher preferably, R 4 is selected from phenyl or thienyl, said phenyl and thienyl are optionally substituted with one or more groups independently selected from fluoro or chloro. R 1 is methyl; L is selected from a single bond or C 1-3 alkylene; preferably, L is selected from a single bond or -CH 2 -; R 2 is selected from 3- to 7-membered cycloalkyl, or 3- to 7-membered heterocycloalkyl, R 2 is optionally substituted with m Rb; m is 0, 1, 2, 3 or 4; each Rb is independently selected from halogen, cyano, hydroxyl, trifluoromethyl, C 1-3 alkyl, C 1-3 alkoxy, C 1-3 hydroxyalkyl, C 1-3 alkylamino or di(C 1-3 alkyl)amino; preferably, Rb is independently selected from F or methyl; R 3 is selected from C 1-3 alkoxy, halogen or C 1-3 alkyl; preferably, R 3 is selected from methoxy, chloro or methyl; R 4 is selected from C 1-3 alkyl, 3- to 7-membered cycloalkyl, 6- to 10-membered aryl or 5- to 6-membered heteroaryl, wherein said 6- to 10-membered aryl and 5- to 6-membered heteroaryl are optionally substituted with one or more groups independently selected from hydrogen, halogen, C 1-3 alkyl, amino, C 1-3 alkylamino, di(C 1-3 alkyl)amino, trifluoromethyl, difluoromethyl, cyano or C 1-3 alkoxy; preferably, R 4 is selected from C 1-3 alkyl, 3- to 7-membered cycloalkyl, phenyl or thienyl, wherein said phenyl or thienyl are optionally substituted with one or more groups independently selected from hydrogen, halogen, C 1-3 alkyl, amino, C 1-3 alkylamino, di(C 1-3 alkyl)amino, trifluoromethyl, difluoromethyl, cyano or C 1-3 alkoxy; futher preferably, R 4 is selected from phenyl or thienyl, said phenyl and thienyl are optionally substituted with one or more groups independently selected from fluoro or chloro. <EOS>