Efficient synthesis of some novel pyrimido[4,5‐e][1,3]oxazine dione derivatives via one‐pot three‐component reaction under thermal and thermal microwave‐assisted conditions

Abstract

AbstractConcise and attractive synthesis of a new class of pyrimido[5,4‐e][1,3]oxazine diones was attained with impressive yields, using a convenient and elegant condensation reaction between thiobarbituric acid and aryl glyoxals in the presence of N‐methyl urea in EtOH under thermal and thermal microwave‐assisted conditions. Some specific merits of the current procedure, include the availability of the starting materials, low reaction time, high reaction yield, operational simplicity, no harmful by‐products, and the high purity of the isolated products. Structures of all the freshly synthesized products have been deduced by their FT‐IR, 1H‐NMR, 13C‐NMR, and elemental analysis.