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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

I. Reactions of omega-linked disaccharides. II. Synthesis of the 2,4-di-O-methyl

Slessor, Keith Norman January 1964 (has links)
I. Reactions of ∝-Linked Disaccharides Through reaction of specifically substituted maltoses, ∝-glucosidic disaccharide derivatives have been prepared. Catalytic oxidation of benzyl β-maltoside yielded maltobiouronic acid. Tritylation of 1,6-anhydro-β-maltose made possible the preparation of the 6'-0-tosyl ester. Replacement of the tosylate with azide ion followed by reduction and hydrolysis yielded a small amount of 6'-amino-6' deoxy-maltose. Replacement of the tosylate with thiolacetate allowed the preparation of 6'-deoxy-6’-mercapto-maltose. Iodide replacement of the sulphonyl ester followed by reduction gave the 6’-deoxy-1, 6-anhydro derivative which was converted to 6’-deoxy-maltose by acetolysis and deacetylation. A route for the preparation of 4-0-(∝-D-glucopy-ranosyluronic acid)-D-xylose by selective decarboxylation of maltosyldiuronic acid was attempted and found unfeasible. Attempts to prepare 6-substituted maltoses by reaction of benzyl 4',6'-0-benzylidene-β-maltoside with various reagents were unsuccessful. II. Synthesis of the 2,4-Di-0-methyl Tetroses The four isomeric 2,4-di-0-methyl tetroses were prepared by periodate oxidation of known methylated sugars. 2,4-Di-0-methyl-D-and L-erythroses were prepared from 4,6-di-0-methyl-D-glucose and 3,5-di-0-methyl-L-arabinose respectively. 2,4-Di-0-methyl-D-and L-threoses were prepared from 3,5-di-0-methyl-D-xylose and 1,4,6-tri-0-methyl-L-sorbose. The tetroses were characterized as their crystalline 2,4-dinitrophenylhydrazones. The Rf and RG values of the free sugars were recorded in a variety of solvents including a silica gel thin-layer chromatography system. / Science, Faculty of / Chemistry, Department of / Graduate

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