| abstract |
Novel benzoheterocyclylglyoxylic acid derivatives of the formula <IMAGE> (I) in which Z is free, etherified or acylated hydroxyl, X is thio or oxy, R is free or etherified hydroxyl, R1 is lower alkyl, cycloalkyl, hydroxyl, lower alkoxy, substituted or unsubstituted phenoxy, substituted or unsubstituted amino, acyl, carboxyl, halogen, nitro or, if Z is acylated hydroxyl and/or X is oxy, hydrogen, R2 is hydrogen, lower alkyl, hydroxyl or halogen and R3 and R4 are each hydrogen or lower alkyl, or in which two adjacent radicals R1, R2, R3 and R4 together form lower alkylene having 3 to 5 chain carbon atoms or 1,4-butadienylene and the other two radicals are each hydrogen, and their pharmaceutically acceptable salts are useful as anti-allergic agents. |