Reaction of 2-ethoxycarbonyl4H,3,1-benzoxazin-4-one with amines

ABSTRACT

Bogert [1] claimed that'2-ethoxycarbonyl-4H-3, l-benzoxazin-4-one [1] reacted with excess aniline to yield the quinazolinone [III], [R=C[6]H[5]]. However, in our previous publications [2, 3]. We reported that the reaction of [1] with amines gave anthranilamides, while its reaction with hydrazines afforded amidrazone type of compounds. Errede and coworkers [4,5]reported that benzoxazinones react with amines in general to give amidines and/or anthranilamides via the nucleophilic attack of the amine on the electrophilic carbon-2 and/or carbon-4 of the benzoxazinone respectively, and only the amidines can undergo facile cyclodehydration to give quinazolinones. In the present study, we decided to reinvestigate the reaction of [I] with amino compounds, aiming at the synthesis of quinazolinone esters of pharmacological interest