New piperazine derivatives of general formula: wherein R is hydrogen or lower alkyl, A is straight or branched lower alkyl and R1 and R2 are respectively hydrogen, amino, alkylamino, dialkylamino mono or di(hydroxyalkyl)amino,morpholino, piperidino, N-alkylpiperazino, 1,3-dithiolan-2-ylidenamino, N-alkylureido, isomers mixture thereof, individual enantiomers and pharmaceutically acceptable acid addition salts thereof. The new compounds exhibit a high antianaphylactic and antibronchospastic activity. |