ALTHOUGH an adequate constitutional formula for sucrose has been developed, attempts to verify this structure by synthesis have led to no success, the only crystalline product isolated being an isomeric disaccharide termed iso-sucrose. Presumably the isomerism resides in the α or β configurations of the glucose and fructose residues present in this disaccharide; and, if so, both sucrose and iso-sucrose should behave in parallel fashion when subjected to the methylation process.