Synthesis and conformational properties of methyl 6,6-di-C-methyl-beta-D-galactopyranoside. Probes for the combining sites of D-galactosyl-binding proteins.
The binding of D-galactopyranosyl groups by lectins and antibodies can involve the 5-hydroxymethyl group. In order to examine the nature of these binding reactions, it was of interest to synthesize 6,6-di-C-methyl-D-galactose which was found to exist, like D-galactose, extensively in the pyranose forms. 2,3,4,6-Tetra-O-acetyl-7-deoxy-6-C-methyl-alpha-D-galacto-heptopyranosyl bromide was prepared under standard conditions and converted into methyl 6,6-di-C methyl-beta-D-galactopyranoside (6). Evidence based on 13C-n.m.r. studies indicates that the favored conformer of 6 has O-4 and O-6 in syn-axial-like relationship. General comments are presented on the nature of the binding of oligosaccharides by proteins.
D001665:Binding Sites; D002135:Calcium-Binding Proteins; D002236:Carbohydrate Conformation; D002352:Carrier Proteins / Q000378:metabolism*; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D008756:Methylgalactosides / Q000138:chemical synthesis*; D008759:Methylglycosides / Q000138:chemical synthesis*; D009004:Monosaccharide Transport Proteins; D009904:Optical Rotation; D033902:Periplasmic Binding Proteins
D002135:Calcium-Binding Proteins; D002352:Carrier Proteins; D007202:Indicators and Reagents; D008756:Methylgalactosides; D008759:Methylglycosides; D009004:Monosaccharide Transport Proteins; D033902:Periplasmic Binding Proteins; C023550:galactose-binding protein; C039513:methyl 6,6-di-C-methylgalactopyranoside