Synthesis of Compounds Related to Antitumor Agents. III. On the Additions of Acyl Halide, Dialkyl Acetylenedicarboxylate and N-Substituted Maleimides to 2, 4-Diamino-5-hydroxy-6-methylpyrimidine

Abstract

2, 4-Diamino-5-hydroxy-6-methylpyrimidine (I) was reacted with acyl halides to give pyrimido [5, 4-b] [1, 4] oxazin-6 (8H)-ones (IIIa, b). Dialkyl acetylenedicarboxylate was made addition with I to afford alkoxycarbonylmethylene-pyrimido [5, 4-b] [1, 4] oxazines (VI, VII). The configuration of this compound was assumed to be cis from the evidence of building pyridazino or furano ring. Similarly, with maleimide, the adduct (XIV) was obtained and converted to pyrimido [5, 4-b] [1, 4] oxazines (XV, XXIa-f).