Abstract
It was experimentally established the "alkaline method" and "diastase method"for assay ing S-carbethoxythiamine-HCl (CET), S-carbobutoxythiamine-HCl (CBT) and O, S-dicarbethoxythiamine-HCl・H_2O (DCET). The alkaline method is based on the fact that CET, CBT and DCET are easily converted into thiamine on treatment with N NaOH at 30℃ for 5 minutes, followed by acidification with N HCl. After this treatment, they can be quantitatively determined with the ordinary thiamine determination procedure. The separation method can be applied for correction the errors produced by contaminants such as thiamine and other thiochrome reaction positive compounds. Except for CET, both CBT and DCET can be determined quantitatively by the diastase method. Each derivative shows the lack of affinity for permutite. However, after treatment with alkaline or diastase, the derivatives behave similarily to thiamine in regards to permutite adsorbability.
