J. Chern, F.-J. Shish, C. Chang
Jul 1, 1988
Citations
0
Influential Citations
12
Citations
Journal
Journal of Heterocyclic Chemistry
Abstract
2,3-Dihydro-5H-oxazolo[2,3-b]quinazolin-5-one 5a was synthesized from anthranilamide 1 and 2-chloro-ethyl isocyanate either by a direct reflux in methanol, or by stirring at room temperature in acetonitrile leading to the intermediate, 2-(2-chloroethyl ureido)benzamide 6a which was subsequently cyclized on heating with an organic base. However, when compound 6a was refluxed with concentrated hydrochloric acid, it furnished 3-(2-chloroethyl)-2,4-dioxo-1H,3H-quinazoline 2a in good yields. 3,4-Dihydro-2H,6.H-[1,3]-oxazino[2,3-b]quinazolin-6-one 5b, 3-(3-chloropropyl)-2,4-dioxo-1H,3.H-quinazoline 2b and 2-(3-chloropropyl ureido)benzamide 6b were obtained similarly from 1 and 3-chloropropyl isocyanate.