チオビタミンB₁の二酸化塩素及びその他の酸化剤による酸化

抄録

Passage of ClO₂ gas in thiothiamine (3-[2′-methyl-4′-aminopyrimidyl-(5′)]-methyl-4-methyl-5-β-hydroxyethylthiazole-2-thione) or its solution results in the formation of thiochrome and the formation of thiamine is hardly detected. Addition of NaClO₂ to the acid solution of thiothiamine results in their reaction with generation of ClO₂ to form thiamine and thiochrome. Thiochrome is quantitatively formed by the addition of an aqueous solution of ClO₂ in a diluted solution of thiothiamine and this reaction also occurs in acidity. Addition of chlorine water to the diluted solution of thiothiamine results in the formation of thiamine and thiochrome, while that of HClO₃ gives only thiamine. Formation of thiochrome was confirmed by extraction with butanol after alkalization while that of thiamine was determined by the ferricyanide-sodium hydroxide method. Thiothiamine is effective as thiamine in animal body but is more easily changed to thiochrome in acid or neutral medium than thiamine that its biological effect must also be weaker.