Synthesis of chitin derivatives having peptide side groups by the water-soluble active ester method

Novel chitin derivatives having pendant monopeptide and tripeptide units, i .e., N-(N'-acetylglycyl)chitin (3a) and N-(N'-acetylglycylglycylglycyl)chit in (3b), were synthesized from 50% deacetylated chitin by the water-soluble active ester method in a homogeneous system at 27-50 degrees C. Without pr otection of hydroxyl groups, amino groups of the partially deacetylated chi tin were selectively acylated by using esters of the corresponding N-acetyl ated amino acids with (4-hydroxyphenyl)dimethylsulfonium.methyl sulfate in water. The degree of substitution of the D-glucosamine moiety of chitin is changed with the feed mole ratio of the active eater reagent to amino group s. As a new type of amphiphilic polysaccharides of lipid/peptide/polysaccha ride conjugates. N-(N'-lauroylglycyl)chitin (3c) and N-(N'-lauroylsarcosyl) chitin (3d) were synthesized in the corresponding way.