Synthetic analgesics: Piperazine analogues of 6-Dimethylamino-4,4-diphenylheptan-3-one ('Methadone')

Abstract

4,4-Diphenyl-6-(4-methyl-1-piperazino)heptan-3-one (II ; R=Me) and 3,3-diphenyl-1-(4-methyl-1-piperazino)hexan-4-one (II ; R=H) have been prepared, the former showing analgesic activity approaching that of morphine, while the latter is inactive. Nevertheless, the methiodide (V) of the inactive base has activity approaching that of morphine. An explanation for these findings is advanced.