Biosynthesis of thiamine. Part II. Origin of the carbon atom in the 2-position of the thiazole component

Abstract

The carbon atom in the 2-position of the thiazole ring in the thiazole component of thiamine can be isolated in good yield as formaldehyde in the form of its dimedone derivative by reduction of the thiazole methiodide with sodium borohydride followed by treatment of the resulting thiazolidine with mercuric chloride and then dimedone. The procedure is suitable for tracer work, and it has been found that the 2-carbon atom of glycine is utilised by yeast as a source of the 2-carbon atom of the thiazole ring.