| abstract |
This invention relates to enzyme inhibitory, novel phthalazin-4-ylacetic acid derivatives of the general formulan wherein R 1 is a hydroxy or benzyloxy radical, or a C 1-4 - alkoxy radical optionally bearing an N-morpholino or a C 1-4 -alkylamino radical, X is oxygen or sulfur, the rings A and B may be substituted, pharmaceutically acceptable salts as appropriate, to pharmaceutical compositions thereof, and to analogy processes for their manufacture. The compounds of formula I are inhibitors of the enzyme aldose reductase in vivo and as such may be useful in the reduction or prevention of the development of the peripheral effects such as macular oedema, cataract, retinopathy or impaired neural conduction. A preferred compound is 2-(2-fluoro-4-bromobenzyl)-1,2-dihydro-1-oxophthalazin-4- ylacetic acid. |