Thirteen (13) compounds of N-phenyl-O-alkyl carbamates (1 and 3), N,N-diethyl-N0 -alkyl/aryl/phenylpiperazinoureas (4–6, 8–12), N-phenyl-N0 -phenylpiperazino/ imidazoureas (2, 7), and N-ethyl-(N0 -phenylpiperazino) thioureas 13 were synthesized and tested for their antidepressant-like activity in mice. It was found that compound N-phenyl-O-heptyl carbamate 1 and N-phenyl-N0 -phenylpiperazinourea 2 showed 32.5 and 27.7% antidepressant activity in the forced swim test in mice, respectively. Considering other carbamates it was found that a decrease in alkyl chain length caused a marked decline in the antidepressant activity. Compounds 1–4 show even higher activities in the forced swim test than the standard phenelzine.