METHOD OF BENFOTHIAMINE SYNTHESIS Russian patent published in 1994 - IPC

FIELD: chemical technology, heterocyclic compounds. SUBSTANCE: synthesis is carried out by benzoylation of thiamine phosphate salt with benzoyl chloride in 20-25% aqueous solution of NaOH at the molar ratio of reagents = 1: (1.06-1.12). Then purification is carried out by reprecipitation of technical product from hot 5-10% HCl with use of 20-25% solution of NaOH. Under these conditions the yield of the end product is up to 78% with 100% content of basic substance. Method is simplified due to decrease of benzoyl chloride consumption, excluding of organic solvents and enhanced effectiveness of benfothiamine purification. EFFECT: increased yield of product, simplified process. 1 tbl