P.m.r. Spectroscopy of trimethyl ethers of D-galactopyranose its derivatives

Abstract

P.m.r. parameters determined at 100 MHz for solutions in deuterium oxide) are presented for trimethyl ethers of D-galactopyranoside (eight), methyl D-galactopyranoside (eight), and galactitol (four). The anomeric and methoxyl proton chemical-shifts of these compounds are compared with those of the corresponding mono-, di-, and tetra-methyl ethers of D-galactopyranose and its derivatives. The results in this and earlier papers show that anomeric change greatly affects the 2-methoxyl signals (in derivatives of D-galactose, D-glucose, and D-mannose); change in configuration at C-4 ( D-galactose compared with D-glucose) affects the neighboring 3-methoxyl signal much more than the 4-methoxyl signal.