Alkyl(E,Z)-2-(2-Benzoyl-2-ethoxycarbonyl-1-ethenyl)amino-3- dimethylaminopropenoates in the Synthesis of Fused Pyrimidinones. A Facile Route to 3-Aminoazino-4H-pyrimidin-4-ones

Article abstract of DOI:10.1002/jhet.5570340521

Alkyl (E,Z)-2K2-benzoyl-2-thoxycarbonyl-1-thenyl)amino-3-dimethylaminopropenoates 1a,b react with neteroarylamines 2 to give alkyl 2-(2-benzoyl-2-ethoxycarbonyl-1-ethenyl)amino-3-heteroarylaminopropenoates 3-13. These were cyclized into fused 3-(2-benzoyl-2-etboxycarbonyl-1-ethenyl)amino-4H-azolo- (or azino)-pyrimidin-4-ones 14-18. 2-Benzoyl-2-ethoxycarbonyl-1-ethenyl group can be easily removed from 3-(2-benzoyl-2-ethoxycarbonyl-1ethenyl)amino-8-methyl-4H-pyrido[1,2-a]pyrimidin- 4-one (14) to give 3-amino-8-methyl-4H-pyrido[1,2-a]pyrimidin-4-one (19). The structure of 1a was confirmed by X-ray analysis.