Syntheses and Enzymatic Hydrolysis of 25-Hydroxyvitamin D Monoglucuronides

Abstract

25-Hydroxyvitamin D₃ (D₂) 3- and 25-monoglucuronides were synthesized from the corresponding provitamin D or its derivatives with the Koenigs-Knorr reaction using silver carbonate as a catalyst, followed by photochemical reaction, thermal isomerization and then alkali hydrolysis. The obtained glucuronides were subjected to enzymatic hydrolysis using β-glucuronidase, and substrate specificities were found in the examined enzymes originating from different sources.