Synthesis of piperidine derivatives with a quinazoline ring system as potential antihypertensive agents.

A series of piperidine derivatives with a 2-oxo-1, 2, 3, 4-tetrahydro-quinazoline or 2, 4-dioxo-1, 2, 3, 4-tetrahydroquinazoline ring at the 4-position were prepared and tested for antihypertensive activity. Among the compounds tested, 1-[2-hydroxy-2-(3, 4-methylenedioxyphenyl)ethyl]-4-(2, 4-dioxo-1, 2, 3, 4-tetrahydro-3-quinazolinyl)piperidine (20) and 1-[2-(4-chlorophenyl)-2-hydroxyethyl]-4-(2-oxo-1, 2, 3, 4-tetrahydro-3-quinazolinylmethyl)piperidine (30) produced relatively strong hypotension in the spontaneously hypertensive rat model.