Studies on Sialic Acids. XV. Synthesis of α-and β-O-Glycosides of 3-Deoxy-D-glycero-D-galacto-2-nonulopyranosonic Acid (KDN)

Abstract

3-Deoxy-D-glycero-D-galacto-2-nonulopyranosonic acid (KDN) was synthesized by basecatalyzed condensation in good yield. Furthermore, benzyl (methyl 3-deoxy-D-glycero-a-D-galacto-2-nonulopyranosid) onate and sodium 2-(5-cholesten-3β-yloxy)-3-deoxy-D-eycero-α-and β-D-galacto-2-nonulopyranosonate were synthesized under Koenigs-Knorr-like reaction conditions, using benzyl (4, 5, 7, 8, 9-penta-O-acety1-3-deoxy-D-glycero-β-D-galacto-2-nonulopyranosyl bromid)-onate as a glycosyl donor. The structure and the stereochemistry of glycosylation products were determined by proton nuclear magnetic resonance and circular dichroism spectral analysis.