| abstract |
A compound of formula (I) ** Formula ++ wherein, R1, is hydrogen, alkyl, haloalkyl, halogen, cyano or carboxy; R2 is hydrogen, alkyl, haloalkyl, halogen, cyano or carboxy; R3 and R4 are, independently, alkyl; R5 and R6 are independently selected from hydrogen, carboxyalkylamino, carboxycycloalkylamino, alkylsulfonylamino, phenylsulfonylamino, halophenylsulfonylamino, alkylphenylsulfonylamino, phenylcarbonylamino, halophenylcarbonylamino, pyridynylsulfonylamino, alkylaminosulfonyl and halophenyl; with the proviso that R5 and R6 are not both hydrogen at the same time; R7 is hydrogen or alkyl; or a pharmaceutically acceptable salt or ester thereof; wherein, "alkyl", alone or in combination, is a saturated, straight-chain or branched-chain alkyl group, which contains 1 to 8 carbon atoms; and "cycloalkyl", alone or in combination, is a saturated carbon ring containing 3 to 7 carbon atoms |