Biologically active 1‐arylpiperazines. Synthesis of N‐[3‐(4‐aryl‐1‐piperazinyl)propyl] derivatives of benzoxazinone and benzoxazolinone

The synthesis of new N‐[3‐(4‐aryl‐1‐piperazinyl)propyl] derivatives of 1H‐2,4‐benzoxazin‐3(4H)‐one ( 1a‐b ), 2H‐1,4‐benzoxazin‐3(4H)‐one ( 2a‐b, 3a‐b and 4b ), and benzoxazolin‐2‐one ( 5a‐b ), as biologically active agents, is described.