Vitamin B₁及び諸関係化合物の研究 第84報

Dihydrothiamineの構造について その2

抄録

In connection with the proposed three isomers of dihydrothiamine, the structure of pseudo-dihydrothiamine was examined. Condensation of 2-methyl-4-amino-5-aminomethylpyrimidine, formaldehyde, and 3-acetyl-3-mercaptopropanol affords normal-dihydrothiamine but the use of a mercaptoketone compound with hydroxyl substituted with other groups, such as 3-acetyl-3-mercaptopropyl benzoate (III) or 3-acetyl-3-mercaptopropyl methyl ether (IV), affords homologs of the pseudo compound. The same result is obtained on the use of 3-acetyl-3-mercaptobutyl acetate (V). From these experimental results and infrared absorption spectral measurements of these reaction products, it is assumed that pseudo-dihydrothiamine and its homologs all possess the skeleton of pyrimido [4, 5-d] thiazolo [3, 4-a] pyrimidine.