A compound of Formula (I): ** Formula ** or a stereoisomer or a pharmaceutically acceptable salt thereof； wherein: R1 is: (a) hydrogen, (b) (CO) n-R3, (c) COOR4 or (d) COCH2COR3； n is 0, 1 or 2； R2 is: (a) SO3M, (b) SO2NH2, (c) PO3M, (d) CH2COOM, (e) CF2COOM, (f) CHFCOOM or (g) CF3； M is hydrogen or a cation； R3 is: (a) hydrogen, (b) C1-C6 alkyl optionally substituted with one or more substituents independently selected from halogen, OR5, CN, COOR5, CONR6R7, NR6R7, NR5COR8, NR5CONR6R7, heterocyclyl, heteroaryl, cycloalkyl or aryl, ( c) CN, (d) NR6R7, (e) CONR6R7, (f) NHCONR6R7, (g) aryl optionally substituted with one or more substituents independently selected from C1-C6 alkyl, OR5, NR6R7, halogen, CN, CONR6R7, SO2- alkyl, SO2-aryl, OSO2-alkyl, OSO2-aryl or NHCONR6R7, (h) heterocyclyl optionally substituted with one or more substituents independently selected from C1-C6 alkyl, OR5, NR6R7, halogen, CN, CONR6R7, SO2-alkyl, SO2 -aryl, OSO2-alkyl, OSO2-aryl, NHC (NH) NR6R7 or NHCONR6R7, (i) heteroaryl optionally substituted with one or more substituents independently selected from C1-C6 alkyl, OR5, NR6R7, halogen, CN, CONR6R7, SO2- alkyl, SO2-aryl, OSO2-alkyl, OSO2-aryl or NHCONR6R7, (j) cycloalkyl optionally It is substituted with one or more substituents independently selected from C1-C6 alkyl, OR5, NR6R7, halogen, CN, CONR6R7, SO2-alkyl, SO2-aryl, OSO2-alkyl, OSO2-aryl or NHCONR6R7, (k) alkyl substituted cycloalkyl C1-C6, wherein C1-C6 alkyl is further substituted with one or more substituents independently selected from OR5, NR6R7, halogen, CN or CONR6R7 or (1) OR8； R4 is: (a) hydrogen, (b) C1-C6 alkyl optionally substituted with one or more substituents independently selected from halogen, OR5, CN, COOR5, CONR6R7, NR6R7, NR5COR8, heterocyclyl, heteroaryl, cycloalkyl or aryl, (c) aryl optionally substituted with one or more substituents independently selected from C1-C6 alkyl, OR5, NR6R7, halogen, CN, CONR6R7, SO2-alkyl, SO2-aryl, OSO2-alkyl, OSO2-aryl or NHCONR6R7
