Watching ripples on crystals: Phys

A pharmaceutical composition containing as its active ingredient a disaccharide derivative having a derivative group of the following formula (1) bonded to a carbon atom of a disaccharide: (1) wherein Y is a member of the group consisting of NH and O; and when Y is NH, Z is a member of the class consisting of -O- (disaccharide residue) and -O-, with the proviso that one of the two bonds is attached to the other carbon atom of the same disaccharide to which the formula (1) group is bonded, and when Y is O, Z is a member of the class consisting of -NH2 and -O-, with the proviso that one of the two bonds is attached to a carbon atom of a disaccharide different from that to which the formula (1) group is bonded. The disaccharide derivative can be prepared by reacting a disaccharide with an activating agent selected from the group consisting of the cyanogen halides, organic cyanic acid esters and halogenocarbonic acid alkyl esters. Said pharmaceutical composition is useful for treating hepatic diseases.