Glycosaminoglycan derivatives and processes for preparing same

The present invention relates to novel glycosaminoglycan derivatives having a neurite outgrowth promoting activity and a sialidase inhibiting activity, a process for producing them, and a pharmaceutical composition containing the glycosaminoglycan derivative as an active ingredient. The invention provides novel glycosaminoglycan derivatives having a repeating unit structure of two saccharides of hexosamine and hexuronic acid as a backbone structure, in which the bonds between 2- and 3-positions carbon atoms of hexuronic acid as its constituting monosaccharide are partially cleaved and a part or all of the 2-position hydroxyl groups of uncleaved hexuronic acid are not substituted with a sulfate group, which has low anticoagulation activity and excellent neurite outgrowth promotion accelerating activity and sialidase inhibition activity; a process for producing the glycosaminoglycan derivatives, comprising a cleavage treatment of the bond between the 2- and 3-position carbon atoms of hexuronic acid having no sulfate group at the 2-position of glycosaminoglycan, and a selective desulfation treatment of the 2-position sulfate group of hexuronic acid; and a pharmaceutical composition comprising the glycosaminoglycan derivative as an active ingredient.