5-Benzoylethyl barbituric acid derivatives 2a-c were prepared as useful precursors for the synthesis of pyrimidine fused heterocycles. Their behaviour as 1, 5-diketocompounds towards aniline derivatives afforded the pyrimidoquinoline derivatives 6a-e. On the other hand, fusion of o-substituted anilines with 1, 3-dimethyl barbituric acid derivatives 8a, b gave the corresponding benzazoles 10a-e. Furthermore, the reaction of 1, 3-dimethyl barbituric ...
[Powers, David G.; Casebier, David S.; Fokas, Demosthenes; Ryan, William J.; Troth, Jonah R.; Coffen, David L. Tetrahedron, 1998 , vol. 54, # 16 p. 4085 - 4096]