PRODUCTION OF MORANOLINE DERIVATIVE

PURPOSE:To obtain a glucosylmoranoline derivative useful as a remedy for diabetes in high yield in high purity, by subjecting a mixture of the glucosylmoranoline derivative and an oliglucosylmoranoline derivative, etc. to fractionating crystallization in method using a polar solvent. CONSTITUTION:A mixture of a moranoline derivative shown by the formula I (R is H, or lower alkyl), a glucosylmoranoline derivative shown by the formula II, and a glucosylmoranoline derivative shown by the formula III (n is 1-5) is dissolved in a polar solvent (e.g., water, methanol, etc.), usually insoluble materials are filtered off, the filtrate is allowed to stand or cooled, to crystallize the glucosyl-momoranoline derivative shown by the formula II. The mixture of the derivatives is obtained by treating an aqueous solution containing the moranoline derivative and cyclodextrin, etc., with cyclodextrin glycosyltransferase.