Oxo Thiamine

Oxo Thiamine is a thiamine derivative featuring a thiazole ring fused to a pyrimidine moiety via an oxo-substituted methylene bridge. The compound exhibits a 2-methyl-4-amino-5-hydroxymethyl thiazole unit linked to a 4-methyl-5-pyrimidinyl disulfide, with an additional carbonyl group (C=O) oxidized at the methylene bridge compared to the parent thiamine structure. This oxidation introduces a ketone functionality, altering its redox properties and stability. The compound arises as a synthetic byproduct during thiamine oxidation processes, particularly under alkaline or aerobic conditions. Its distinct UV absorption and chromatographic profile enable its identification as a critical impurity in thiamine API batches, serving as an HPLC reference standard for impurity quantification.