Synthesis of novel 1,4-disubstituted piperazines as potential antihypertensive agents

Two series of 1-arylpiperazines linked to nicotinic acid moiety were prepared as potential antihypertensive agents. The first series [compounds II] was prepared via the Mannich reaction of N-nicotinoyl with 4-amino-benzoic acid to give N-nicotinoyl-4-aminobenzoic acid. The latter was treated with thionyl chloride to give the corresponding acid chloride which was reacted with 1-arylpiperazines to give IV. Preliminary screening of the synthesized compounds was performed for their antihypertensive activity