NEW MATERIAL:Compounds expressed by formulas I to V (R is aliphatic acyl; R1 is H or lower alkyl; R2 to R5 are equally H or independently acyl; R6 is N3, NH2, etc.; (n) is 0-20, provided that R2 to R5 are H when R1 is H and acyl when R1 is lower alkyl; R7 is NHCOCH3, etc.; R8 is 1-30C alkyl or benzyloxy, provided that R2 to R5 are acyl when R8 is benzyloxy).

USE: A medicine for senility or carcinostatic agent.

PREPARATION: A 2-α-O-glycoside compound is used as a starting material and reacted in a nonpolar solvent, such as BF3-ether, at 0°C to ambient temperature and the resultant compound is then reacted with trichloroacetonitrile in a solvent, such as dichloromethane. The obtained compound is subsequently reacted with an azidosphingosine derivative expressed by formula VI in the presence of a Lewis acid in a nonpolar solvent.