Substituted amides

摘要

The invention comprises compounds of the formula: (wherein R1 and R2 are alkyl radicals each containing at most 3 carbon atoms, R3 and R4 are alkyl radicals each containing at most 4 carbon atoms or, together with the nitrogen atom form a saturated 5- or 6- membered heterocyclic ring system, and n is 1,2 or 3) and their preparation by reacting the appropriate acid halide with the appropriate amine or by reacting the appropriate acid with the appropriate di-substituted carbamyl halide. In these starting materials the group R1 may be replaced by a protecting group e.g. an acyl or benzyl group, in which case after the condensation the protecting group is removed e.g. by hydrolysis or hydrogenolysis and the free hydroxy group then alkylated. Examples are given. Acylhalides of the formula: (wherein R1, is the alkyl group R1 or a blocking group which can be replaced by a hydrogen atom, e.g. an acyl or benzyl group) are prepared from the corresponding acids and thionyl chloride. The amides of the invention which are stated to be respiratory analeptics may be made up into pharmaceutical compositions e.g. injection solutions, and drops for oral administration, with suitable carriers. Ampoules and drops containing 3,4 - dimethoxy - phenylacetic acid- N - dimethylamide are described.