Vitamin b, active o-arylthiaminedisulphides - selective preparation

摘要

O-acylthiaminedisulphides, superior to thiamine-HCl in vitamin B1 activity are prepd. without simultaneous formation of the N-acyl compounds by reacting thiamine-disulphides with thiosulphates and a reactive acide halide or anhydride in water or an aqs. org. solvent at 5-15 degrees and pH 7-8.5. In an example 10.1g. O-benzoylthiaminesulphide, m.p. 147 degrees are obtained from 14g thiaminedisulphide reacted with 12.6g Na-thiosulphate and 9.0g benzoylchloride in an aqueous medium at 5-15 degrees and pH 7.8