Oligosaccharides Related To Tumor-associate Antigens .4. Modeling of the Terminal Tetrasaccharide of An Antigen Recognized By the Mbr1 Antibody and of Overlapping Disaccharide and Trisaccharide Sequences

The conformational space of the tetrasaccharide alpha-L-Fuc-(1 --> 2)-beta-D-Gal-(1 --> 3)-beta-D-GalNAc-(1 --> 3)-alpha -D-Gal1Pr (3) and of some overlapping di- and trisaccharide sequences was investigated with the aid of molecular-mechanics energy minimizations, molecular-dynamics simulations, and H-1-NMR analysis. These investigations suggested that in compound:) a certain rigidity of the first two glycosidic linkages (Fuc-Gal and Gal-GalNAc) is combined with the flexibility of the third one (GalNAc-Gal).