A New Synthesis of 1,4-Thiazin-3-ones by a Novel Rearrangement of 1,4-Oxathiins

摘要

Much of the research in heterocyclic chemistry is concerned with the development of new methods for ring syntheses. There has been an increasing interest over the past several years in the chemistry of 1,4-thiazin-3-one derivatives. This is primarily due to their remarkable spectrum of biological activity. Examples of their biological activity are phospholipase A_2, lipoxygenase and cyclooxygenase inhibitors, protective agents against endotoxin shock, and cardiotonics. However, very few convenient syntheses of 1,4-thiazin-3-ones are currently available. In this study we report a facile, general synthesis of these compounds through an acid-catalyzed rearrangement of 1,4-oxathiins 1.