Synthesis of Amphiphilic Chitopentaose and Chitoheptaose Derivatives Using a Common Disaccharidic Synthon as the Chain Elongation Unit

With interest in clustering bioactive chitooligosaccharides, a pair of amphiphilic derivatives of around DP (degree of polymerization) 6, which has been considered to be the minimum molecular length for some kinds of bioactivity, was synthesized. Homologous derivatives of chitopentaose and chitoheptaose carrying tetradecanoyl and tetradecyloxy groups at the NH and C-1 of the reducing ends, respectively, were actually obtained using a 1,6-anhydro-2-azido-2-deoxy-β-D-glucopyranose derivative as the terminal precursor and a chitobiose derivative as the elongation unit. Micelle formation of both derivatives was assumed from the results obtained by dye solubilization tests.