A compound of formula (I) or a pharmaceutically acceptable ester, amide, carbamate, solvate or salt thereof, including a salt of such an ester, amide or carbamate, and a solvate of such an ester, amide, carbamate or salt, ** Formula ** wherein R1 is selected from the group consisting of halogen, cyano, nitro, ORA, N (RB) 2, -C (O) C1-4 alkyl, - SO2 C1-4 alkyl, C1-6 alkyl, alkenyl C2-6, C2-6 alkynyl, C1-6 haloalkyl, C1-6 dihaloalkyl, C1-6 trihaloalkyl, C2-6 haloalkenyl, C2-6 dihaloalkenyl, C2-6 trihaloalkenyl, C1-6 cyanoalkyl, C1-4 alkoxy C1-6, C3-8 cycloalkyl, C3-8 cycloalkyl-C1-6 alkyl, phenyl, benzyl, and 5-10 membered heterocyclyl, wherein said phenyl, benzyl or heterocyclyl group may be unsubstituted or substituted with 1 to 3 substituents, each substituent being selected from the group consisting of ORA, halogen, cyano, nitro, -C (O) C1-4 alkyl, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C1-6 haloalkyl dihaloalkyl C1-6 and trihaloalkyl C1-6； R2 is selected from the group consisting of halogen, cyano, nitro, ORA, N (RB) 2, N (OH) 2, -C (O) C1-4 alkyl optionally substituted with 1 to 3 halogens, -SO2 C1-alkyl 4, -C (O) NH-OH, -C (NH2)>； = N-OH, -C (CO2H)>； = N-OH, - C (NH2)>； = NH, -C (NH4-4alkyl) >； = NH, -C (O-C1-4 alkyl)>； = NH, -C (NH2)>； = N-NH2, -NH-C (NH2)>； = NH, -NH-C (O) NH2, - N>； = C (- NH-CH2CH2-NH-), -S-CN, -SC (NH2)>； = NH, -SC (NH2)>； = N-OH, -CO2H, -CH2-CO2H, -CH ( OH) CO2H, -C (O) CO2H, SO3H, CH2SO3H, C1-6 alkyl, C1-6 haloalkyl, C1-6 dihaloalkyl, C1-6 trihaloalkyl, C1-6 cyanoalkyl, C1-4 alkoxy-C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C3-8 cycloalkyl, C3-8 cycloalkyl-C 1-6 alkyl, phenyl, benzyl and 5-10 membered heterocyclyl wherein said phenyl, benzyl or heterocyclyl group may be unsubstituted or substituted with 1 to 3 substituents, each substituent being selected from the group consisting of ORA, halogen, cyano, nitro, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 1-6 dihaloalkyl and C1-6 trihaloalkyl； with the
