Enzymatic Utilization of P 1 -Di- N -acetylchitobiosyl P 2 -Dolichyl Pyrophosphate and Its Chemical Synthesis

Abstract

Fully acetylated chitobiose was treated with phosphoric acid to give a mixture of products from which 2-acetamido-4-O-(2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-beta- D-glucopyranosyl)-3,6-di-O-acetyl-2-deoxy-alpha,beta- D-glucopyranosyl phosphate (Ac(3)GlcNAc-Ac(2)GlcNAc-P) was isolated by preparative thin layer chromatography. Treatment of this compound with P(1)-diphenyl P(2)-dolichyl pyrophosphate gave an acetylated pyrophosphate diester, which was purified chromatographically and deacetylated. The product, P(1)-di-N-acetylchitobiosyl P(2)-dolichyl pyrophosphate (Dol-P-P-GlcNAc-GlcNAc), was readily separated from P(1)-2-acetamido-2-deoxy-alpha-D-glucopyranosyl P(2)-dolichyl pyrophosphate (Dol-P-P-GlcNAc) by thin layer chromatography in several solvent systems. Addition of this compound to human lymphocyte membrane preparations led to the formation of a mannose-containing derivative which appears to be an oligosaccharide phospholipid, as judged by its behavior on DEAE-cellulose chromatography and by its hydrolysis to give an oligosaccharide containing more than four monosaccharide units.