Glucosan and derivs

These various possibilities for oxidation-resistant 1,2-diols demonstrate the need for caution in the interpretation of the results of periodate and lead tetraacetate oxidation. As in the studies of D-glucosan < 1,4 > 0-< 1,6> and D-galactosana, supporting evidence based on other chemical reactions and the formation of derivatives should be obtained for the choice between absence of adjacent hydroxyl groups and presence of resistant 1,2-diols. 

D-Glucosan (1,5)/3(1,6) and its 3-methyl derivative are believed to form low rotating complexes involving the hydroxyl groups on carbon atoms 2 and 4. Approximate calculations of the 02—04 distance indicates that such complexing might be expected provided the pyranoside... 

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