Abstract
4-Amino-2-butylthio-5-hydroxymethylpyrimidine (3) corresponding to the 2-subst,ituted pyrimidine moiety in thiamine was prepared from ethyl ethoxy-methylenemalonate in an overall yield of 46.7% in 4 steps. This product was chlorinated with thionyl chloride followed by condensation with 4-methyl-5-(β-hydroxyethyl)thiazole in dioxane to give 2-butylthiothiamine (2). The inhibitory effect of (2), (3) and 2-methylthiothiamine (1) on the growth of Saccharomyces carlsbergensis was examined under the following three culture conditions: a) vitamin B_1 and B_6 free medium, b) B_6 supplemented medium, and c) both B_1 and B_6 supplemented medium. Both compounds inhibited the growth of S. carlsbergensis under these conditions, the order of inhibitory po-tency being a) (1)>(3)>(2), b) (1)>(2)>(3), and c) (2)≧(1)>(3).
