Identification of di-O-, tri-O-, and tetra-O-methylmannoses by gas–liquid chromatography

Some di-O- and tri-O-methylmannoses which are unknown or difficult to prepare have been synthesized. These and the other isomers, which can arise from methylation–fragmentation analyses of mannofuranose- and mannopyranose-containing polysaccharides can be used as gas–liquid chromatographic (g.l.c.) standards. A system has been devised in which methylation fragments are fractionated on a cellulose column into di-O-, tri-O-, and tetra-O-methylmannose fractions, which are then analyzed individually by g.l.c. following conversion to suitable derivatives.