| abstract |
Compounds of the formula (I), and pharmaceutically acceptable salts thereof:n wherein:n R, is hydroxy, C 1-4 alkoxy or an in-vivo hydrolysable acyloxy group: R 2 is hydrogen, C 1-4 alkyl, hydroxy, C 1-4 alkoxy or an in-vivo hydrolysable acyloxy group; R 4 is benzofuryl, benzothienyl, indolyl, quinolyl, isoquinolyl,2,3-dihydrobenzofuryl, 2,3-dihydrobenzylthienyl or 2,3-dihydroindolyl optionally substituted by one or two substituents selected from C 1-4 alkoxy, hydroxy or acyloxy, trifluoromethyl, halogen or nitro; and A is a bond or C 1-6 alkylene, a process for their preparation, and pharmaceutical compositions containing them. |