H 2 O 2 -Mediated Synthesis of a Quinazolin-4(3 H )-one Scaffold: A Sustainable Approach.

A quinazolin-4(3 H )-one ring system is a privileged heterocyclic moiety with distinctive biological properties. From this perspective, the development of an efficient strategy for the synthesis of quinazolin-4(3 H )-one has always been in demand for the synthetic chemistry community. In this report, we envisaged an efficient protocol for the synthesis of quinazolin-4(3 H )-one using substituted 2-amino benzamide with dimethyl sulfoxide (DMSO) as a carbon source and H 2 O 2 as an effective oxidant. Mechanistically, the reaction proceeds through the radical approach with DMSO as one carbon source. To further substantiate the synthetic claim, the synthetic protocol has been extended to the synthesis of the anti-endotoxic active compound 3-(2-carboxyphenyl)-4-(3 H )-quinazolinone.