Abstract: N-(2-Aminocyclopentyl)N-alkanoylanilides and their 2-N-oxides of the formula ##STR1## e.g., trans-3,4-dichloro-N-[2-(dimethylamino)cyclopentyl]propionanilide, and their pharmacologically acceptable salts, have been found to possess potent Central Nervous System anti-depressant properties. Many of them are new.These compounds are promising anti-depressant drugs which are characterized by a better therapeutic ratio than imipramine, and long acting activity which may allow longer durations between administrations, e.g., once a day. Pharmaceutical compositions containing these compounds and a process for treating conditions of depression with these compositions are disclosed.