β-Glucosyl and β-galactosyl transfer catalysed by β-1,4-galactosyltransferase in preparation of glycosylated alkaloids

Abstract

Bovine β-1, 4-galactosyltransferase mediates the transfer of galactose from uridine 5′-diphosphogalactose and also transfer of glucose from uridine 5′-diphosphoglucose to elymoclavine 2-acetamido-2-deoxy-β-D-glucopyranoside 2a, yielding the respective diglycosides 3 and 4. Both reactions were optimised on a semipreparative scale. The products were characterised by NMR spectroscopy and mass spectrometry.