Ring-fused pyrazolo[3,4-d]-pyridin-3-one derivatives as benzodiazepine receptor modulators

Claim 1

A compound of the formula ##STR28## wherein A together with the two carbon atoms to which it is attached represents a fused 5-, 6- or 7-membered carbocyclic or heterocyclic ring selected from (a) cyclopenteno, cyclohexeno and cyclohepteno; each unsubstituted or mono- or di-substituted or carbon atoms within A by lower alkyl, hydroxy, lower alkanoyloxy, aroyloxy, oxo, lower alkoxy, aryl, aryl-lower alkyl or aryl-lower alkoxy; (b) dihydrothieno, dihydrothiopyrano and tetrahydrothiepino; each unsubstituted or mono- or di-substituted on carbon atoms within A by lower alkyl, lower alkoxycarbonyl, aryl or aryl-lower alkyl; or the S-mono- or di-oxo derivative of any said ring; (c) dihyrofuro, dihydropyrano, and tetrahydrooxepino; each unsubstituted or mono- or disubstituted on carbon atoms within A by lower alkyl, lower alkoxycarbonyl, aryl or aryl-lower alkyl; (d) dihydropyrrolo, tetrahydropyrido and tetrahydroazepino; each unsubstituted, or substituted on nitrogen by lower alkoxycarbonyl, carbamoyl, mono- or di-lower alkylcarbamoyl, monoarylcarbamoyl, lower alkyl, aryl-lower alkyl, lower alkanoyl, aroyl or aryl-lower alkanoyl; each unsubstituted or mono- or disubstituted on carbon atoms within A by lower alkyl, oxo, aryl or aryl-lower alkyl; R 1 represents lower alkyl, phenyl, or phenyl substituted by one or two radicals selected from lower alkyl, lower alkoxy, halogen and trifluoromethyl; or R 1 represents an aromatic heterocyclic radical selected from pyridyl, quinolyl, isoquinolyl, pyrimidyl and thiazolyl, or any said heterocyclic aromatic radical mono- or di-substituted by lower alkyl, lower alkoxy or halogen; R 2 , R 3 and R 3 ' independently represent hydrogen or lower alkyl; and the term aryl within any of the above definitions represents phenyl or phenyl mono- or disubstituted by lower alkyl, lower alkoxy, hydroxy, lower alkanoyloxy, aroyloxy, halogen or trifluoromethyl; or a pharmaceutically acceptable salt thereof.