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Polysaccharides helical

MOLECULAR ARCHITECTURE OF POLYSACCHARIDE HELICES IN ORIENTED FIBERS... [Pg.311]

Five articles on polysaccharide helices solved prior to 1979 have appeared in the volumes published between 1967 and 1982.2-6 The first was a review on X-ray fiber diffraction and its application to cellulose, chitin, amylose, and related structures, and the rest were bibliographic accounts. Since then, X-ray structures of several new polysaccharides composed of simple to complex repeating units have been successfully determined, thanks to technological advances in fiber-diffraction techniques, the availability of fast and powerful computers, and the development of sophisticated software. Also, some old models have been either re-... [Pg.312]

A putative packing arrangement in the monoclinic unit cell (Fig. 40b) reveals that there are no direct interactions among the main chains of adjacent helices. However, the peripheral side chains form hydrogen bonds with both main and side chains. As in the case of 46, the ordered structure of 47 supports the hypothesis that side chains often promote the formation of stable, branched polysaccharide helices. [Pg.399]

Cartesian and cylindrical polar atomic coordinates of the structural repeating unit of 31 polysaccharide helices are provided in Tables A1 to A31. Errors, if any, in the original publications have been corrected. The coordinates of hydrogen atoms are given in a majority of structures. If missing, they are not available in the references cited in Table I. Each table caption contains the structure number and polymer name assigned in Table I. Refer to Table II for its chemical repeating unit. Cartesian (x, y, z) and cylindrical (r, , z) coordinates are related by x r cost ), y = r sin<(> and z is the same in both systems. [Pg.404]


See other pages where Polysaccharides helical is mentioned: [Pg.313]    [Pg.315]    [Pg.317]    [Pg.319]    [Pg.321]    [Pg.325]    [Pg.327]    [Pg.329]    [Pg.331]    [Pg.333]    [Pg.335]    [Pg.337]    [Pg.339]    [Pg.341]    [Pg.343]    [Pg.345]    [Pg.347]    [Pg.351]    [Pg.353]    [Pg.355]    [Pg.357]    [Pg.359]    [Pg.361]    [Pg.363]    [Pg.367]    [Pg.369]    [Pg.371]    [Pg.373]    [Pg.375]    [Pg.377]    [Pg.379]    [Pg.381]    [Pg.383]    [Pg.385]    [Pg.387]    [Pg.389]    [Pg.391]    [Pg.393]    [Pg.395]    [Pg.397]    [Pg.399]    [Pg.401]    [Pg.403]    [Pg.405]    [Pg.407]    [Pg.409]    [Pg.411]   
See also in sourсe #XX -- [ Pg.42 , Pg.144 ]




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