A compound of Formula (I): ** Formula ** or a stereoisomer thereof, or a pharmaceutically acceptable salt thereof, wherein: Q is selected from C and N； R1, R2, R3 and R4, which may be the same or different, each is selected from hydrogen, halogen, alkyl, alkenyl, cycloalkyl, aryl, heterocyclyl, heteroaryl, alkynyl, -CN, -NR6R7, -OR6, -COR6 , -CO2R6, -CONR6R7, - C (>； = NR6) NR7R8, -NR6COR7, -NR6CONR7R8, -NR6CO2R7, -SO2R6, -NR6SO2NR7R8, -NR6SO2R7 and -NR6SO2aryl, where alkyl, alkyl, heteroaryl, alkyl, heteroaryl, alkyl, heteroalkyl, alkyl aryl and heterocyclyl are optionally independently substituted with at least one R9 substituent, or (R1 and R2) and / or (R3 and R4), together with the ring to which they are attached, form a fused ring selected from heterocyclyl and heteroaryl rings optionally substituted with at least one R9 substituent； with the condition that R1 is absent when Q is N； R5 is selected from alkyl, cycloalkyl, heterocyclyl, aryl, heteroaryl rings, each of which is optionally substituted with at least one R9 substituent； R6, R7 and R8, which may be the same or different, each selected from H, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl and heteroaryl； or (R6 and R7) and / or (R7 and R8), together with the atom (s) to which they are attached, each forms a ring selected from heterocyclyl and heteroaryl rings optionally substituted with at least one R9 substituent； R9 is selected from halogen, haloalkyl, alkyl, alkenyl, cycloalkyl, aryl, heteroaryl, heterocyclyl, alkynyl, oxo, -alkyl-NR'R '', -CN, -OR ', -NR'R' ', -COR' , -CO2R ', -CONR'R' ', -C (>； = NR') NR''R '' ', nitro, -NR'COR' ', - NR'CONR'R' ', -NR'CO2R '', -SO2R ', -SO2aryl, -NR'SO2NR''R' '', NR'SO2R '' and -NR'SO2aryl, wherein the cycloalkyl, aryl, heteroaryl or heterocyclyl group is each optionally substituted independent by one, two or three substituents selected from halo, alkyl and haloalkyl, wherein R ', R' 'and R' '' are independently selected from H, haloalkyl, alkyl, al
