Transformations of dimethyl acetone-1,3-dicarboxylate. The synthesis of (4-oxo-4H-pyrido[1,2-a]pyrimidin-3-yl)thiazole-5-carboxylates

Abstract

Dedicated to Professor Henk van der Plas on the occasion of his 80th anniversary AbstractMethyl 2-amino-4-(2-methoxy-2-oxo-ethyl)thiazole-5-carboxylate (2a), prepared from dimethyl acetone-1,3-dicarboxylate (1), sulfuryl chloride and thiourea according to a known procedure, was transformed in two steps into (4H-pyrido[1,2-a]pyrimidin-3-yl)thiazole-5-carboxylates (6).

Enaminone, Enaminoesters, and Related Compounds in the Metal‐Free Synthesis of Pyridines and Fused Pyridines

“…No attempts were made to determine their configurations. Heating 101 with α‐aminoheterocycles (or the corresponding dimethylamino substitution‐intermediates) in acetic acid under reflux give substituted (4 H ‐pyrido[1,2‐ a ]pyrimidin‐3‐yl)thiazole‐5‐carboxylates 102 . (Scheme ).…”