Y. Iwanami
May 1, 1971
Citations
0
Influential Citations
11
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
Methyl and ethyl isoxanthopterin-6-acetates and their 4-amino analogues have been prepared via a new route from acetylenedicarboxylate and 2,5,6-triamino-4-hydroxypyrimidine or 2,4,5,6-tetraaminopyrimidine. These compounds uniquely exist in the imine form as evidenced by NMR and IR spectral data. This is the only exceptional case so far examined, since a number of related compounds exist in enamine form. When dissolved in sulfuric acid, however, tautomerization of imine to enamine is observed. It was demonstrated by NMR inspection that the methylene hydrogen on the side chain is exchangeable with deuterium. The tautomerism in sulfuric acid is discussed.