A method of biological determination of thiamine thiazolone was devised utilizing thiamine biosynthesis from the compound and MHT by Saccharomyces cerevisiae. By means of the method thiamine thiazolone was detected in urine of the rat administered OBT intraperitoneally. This result suggests that OBT was metabolized by O-acylthiamine oxidase to thiamine thiazolone, in vivo.
