A compound having the formula (I) ** Formula ** or its pharmaceutically acceptable salts, solvates or hydrates, wherein R1 and R2 are selected from (i), (ii), (iii), (iv) and (v ) as follows: (i) R1 and R2 together form>； = O,>； = S,>； = NR9 or>； = CR10R11； (ii) R1 and R2 are both -OR8, or R1 and R2, together with the carbon atom to which they are attached form dioxacycloalkyl； (iii) R1 is hydrogen or halogen； and R2 is halogen； (iv) R1 is alkyl, alkenyl, alkynyl, cycloalkyl or aryl, wherein the alkyl, alkenyl, alkynyl, cycloalkyl or aryl is optionally substituted with one or more substituents selected from halogen, cyano, alkyl, -RxORw, -RxS (O ) qRv, -RxNRyRz and -C (O) ORw； and R2 is halogen or -OR8； and (v) R1 is halogen, -OR12, -NR13R14, or -S (O) qR15； and R2 is hydrogen, deuterium, alkyl, alkenyl, alkynyl, cycloalkyl or aryl, wherein the alkyl, alkenyl, alkynyl, cycloalkyl or aryl is optionally substituted with one or more substituents selected from halogen, cyano, alkyl, -RxORw, -RxS (O) qRv and -RxNRyRz； R3 is hydrogen, halogen, alkyl, cyano, halogenoalkyl, cycloalkyl, cycloalkylalkyl, hydroxy or alkoxy； R4 and R5 are each independently hydrogen or alkyl； each R6 is independently selected from halogen, alkyl, alkenyl, alkynyl, halogenoalkyl, cycloalkyl, -RxOR18, -RxNR19R20 and -RxS (O) qRv； each R7 is independently halogen, alkyl, halogenoalkyl or -RxORw； R8 is alkyl, alkenyl or alkynyl； R9 is hydrogen, alkyl, halogenoalkyl, hydroxy, alkoxy or amino； R10 is hydrogen or alkyl； R11 is hydrogen, alkyl, halogenoalkyl or -C (O) OR8； R12 is selected from hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, aryl, aralkyl, heteroaryl, heteroaralkyl, -C (O) Rv, -C (O) ORw and -C (O) NRyRz, in wherein alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, aryl, aralkyl, heteroaryl and heteroaralkyl are each optionally substituted with one or more substituents independently selected fr
