Synthesis and biological evaluation of novel quinazolin-4(3H)-one Schiff base derivatives as nitric oxide synthase inhibitors

Synthesis of new Schiff base derivatives bearing a 6-nitro-2-ibuprofenyl-4(3H)-quinazolin-4-one skeleton, as well as their in vitro biological evaluation as inhibitors of nitric oxide synthase (iNOS and nNOS) isoforms, is defined. Structures of these novel heterocycles were confirmed based on their spectral, (IR, 1H NMR, 13C NMR and MS) and elemental analyses. In general, the assayed compounds behave as better iNOS than nNOS inhibitors. Quinazolinyl Schiff bases 9a-e are the most active inhibitors of all tested compounds and the most iNOS/nNOS selective of all studied compounds, with expected potential as anti-stroke agents.