Abstract
In order to study more in detail the formation of thiaminic acids by the oxidation of thiol type thiamine derivatives, the oxidation condition of O-benzoylthiamine disulfide (BIDS) was investigated and the following results were obtained. In the oxidation with hydrogen peroxide, nearly the same yield was obtained in lower fatty acids such as acetic, formic, propionic or butyric acid and in its solution in water or various organic solvents. Further optimal condition was that more than 5 moles of H2O2 per mole of BTDS was allowed to react at about 40° for 2 to 4 days, whereby the yield was about 50%, showing that at least one mole of O-benzoylthiaminic acid (BTnA) was produced from one mole of BTDS. Furthermore, it was observed that BTnA was also obtained by H2O2 oxidation in an aqueous solution (pH 4-9) or by oxidation of bromine, permanganate or bichromate though in a fairly reduced yield.
