Vitamin B₁関係化合物の研究 (第5報)

3-[2´-Methyl-4´-aminopyrimidyl-(5´)]-methyl-4-methyl-5-β-acyloxyethyl-thiothiazolohe-(2)の過酸化水素酸化によるVitamin B₁エステルの合成

抄録

An addition of 3 moles of hydrogen peroxide to a suspension of 1 mole of O-acetyl, O-propionyl or O-benzoyl substituent (II, V or VI) of 3-[2′-methyl-4′-aminopyrimidyl-(5′)]-methyl-4-methyl-5-β-hydroxyethyl-thiothiazolone-(2) (I) in water, at 25-35°, results in generation of heat and in solvation of the crystals. Evaporation of the reaction mixture under a reduced pressure and addition of absolute alcohol to the residue yield acetyl-, propionyl- or benzoyl-thiamine sulfate (III, VII or VIII). Treatment of the reaction mixture with BaCl₂ yields the hydrochlorides (IV, IX and X) of acylated thiamines. (II) and (V) can be prepared in a good yield by the respective boiling (I) with glacial acetic acid or propionic acid.