| abstract |
A compound of the formula <IMAGE> Formula I wherein: R1 is independently selected from hydrogen, lower-alkyl, cycloalkyl, cycloalkyl lower-alkyl, lower-alkoxy, formyl, (lower-alkyl)-hydroxylmethyl, aryl, benzyl, arylmethyl, pyridylmethyl, where aryl, benzyl, arylmethyl and pyridylmethyl are unsubstituted or independently mono, di or tri substituted with hydrogen, hydroxy, thiol, amino, halo, nitro, lower-alkylthio, lower-alkoxy, mono-lower-alkylamino, di-lower-alkylamino, hydroxycarbonyl, lower-alkoxycarbonyl, hydroxysulfonyl, lower-alkoxysulfonyl, lower-alkylsulfonyl, lower-alkylsulfinyl, trifluoromethyl, cyano, tetrazoyl, carbamoyl, lower-alkylcarbamoyl, and di-lower-alkylcarbamoyl; and R2, R3, R4, R5 and R6 are as set forth in the specification. |