Synthesis of N-acetyllactosamine containing a -[6-3H]galactopyranosyl group

Abstract

A simple and convenient method for the introduction of radiolabel onto C-6' of N-acetyllactosamine is described. 1-N-Benzyl-3-O-[beta]--galactopyranosyl--arabinosylamine (1) was synthesized from 3-O-[beta]--galactopyranosyl--arabinose as described by Lee and Lee. Compound 1 was oxidized with -galactose oxidase, and the product reduced with KB3H4 to introduce the label at C-6'. After dilution with unlabeled material, the N-benzyl-3-O-[beta]--[6-3H]galactopyranosyl--arabinosylamine was converted into 2-(benzylamino)-2-deoxy-4-O--[6-3H]galactopyranosyl--glucononitrile, which was subjected to simultaneous hydrogenolysis of the benzylamino and nitrile groups. N-Acetylation of the amino group as described by Alais and Veyrieres afforded the crystalline title compound in 63% yield.