3,4-Diphenyl-1H-pyrazole-1-propanamine antidepressants

A small series of compounds is described in which a narrow SAR has identified N,N-dimethyl-3,4-diphenyl-1H-pyrazole-1-propanamine, 3, as a potential antidepressant with reduced side effects. The isomeric N,N-dimethyl-4,5-diphenyl-1H-pyrazole-1-propanamine was completely inactive in the primary antidepressant screens. Compounds were synthesized by Michael addition of acrylonitrile to diphenylpyrazole followed by reductive alkylation of the resultant diphenylpyrazolepropionitriles. Compound 3 was equipotent with imipramine in standard antidepressant assays in animals but showed no significant anticholinergic action and did not antagonize the antihypertensive effects of clonidine and guanethidine.