Synthesis of glucosamine derivative with double caffeic acid moieties at N– and 6-O-positions for developments of natural based materials

Glucosamine derivatives with double caffeic acid moieties were synthesized for developments of natural based materials. Caffeic acids were introduced to glucosamine derivatives through the synthesis roots as protection and de-protection reactions. Firstly, the silyl groups and tert-butoxycarbonyl groups were selected for the protection of each hydroxyl group and amino group. The designed glucosamine derivative showed reactivity of the double bonds, which was confirmed by UV spectra. Photoresponsivity was observed both in solution and heterogeneous suspension. The oligomerization was also confirmed in water suspension. The solubility and thermal stability were changed after the UV irradiation. This results show the potential of great progress a natural based material development. [Display omitted] •Two caffeic acids are successfully connected at N- and 6O-positions of glucosamine.•Photoresponsive middle molecules are designed with caffeic acids and glucosamine.•Oligomerization was confirmed by UV irradiation.•Pentamer was confirmed by MALDI-TOF/MS after UV irradiation.•Synthetic route for the glucosamine derivatives has been developed.