Synthesis, NMR and Conformational Studies of Fucoidan Fragments 1:1 Desulfated 2,3- and 3,4-Branched Trisaccharide Fragments and Constituting Disaccharides

ABSTRACT Two fucotriosides with vicinal disubstitution α-L-Fuc-(1→2)[α-L-Fuc-(1→3)]α-L-Fuc-OPr (1) and α-L-Fuc-(1→3)[α-L-Fuc-(1→4)]α-L-Fuc-OPr (2), which are related to fragments of natural polysaccharides fucoidans, have been synthesized together with constituent disaccharides 3-5. Spectral and conformational properties of tri- and disaccharides have been investigated by 1H, 13C and NOE NMR spectroscopy.