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The water soluble polysaccharide isolated from rye flour gave on hydrolysis, Xylose (60%), arabinose (29%) and glucose (5%). After methylation of the hemicellulose, the sugars obtained on hydrolysis of the product were separated on a cellulose column, giving 2:3:5-tri-O-methyl-L-arabinose (5 parts), 2:3-di-0-methyl- D-xylose,(6) 2-0-methy1 -D-xylose (5) and a small amount of D-xylose. The general structure of the xylan is therefore similar to other known araboxylans, having a backbone of l:4 linked xylopyranose units with terminal arabinose units linked through position 3. In the isolation of the trisaccharide, Q-L-arabofuranosyl (1→3)- 0-D -xylopyranosyl (1→4) -D-xylopyranose, it has been shown that some of the arabinose units are in the form of single side chains. 4-0-Methyl-D-xylose has been synthesised from D-arabinose, and it has been shown to degrade in alkali giving mainly formic acid and xyloisosaccharinic acid, which is the expected product from sugars with 1:4-linked xylose residues. The action of alkali on various cereal xylans has been studied. The degradation products have been shown to include formic, lactic acids together xyloisosaccharinolactone and small quantities of xylometasaccharinolactones. Xylometasaceharinolactone has been found to be present in the hydrolysis products of the alkali stable rye polysaccharide. The mechanisms for the degradation and stopping reactions are discussed. Two unsuccessful attempts have been made to synthesise 1:5-dihydroxypentan-2:3-dione.

The aim of the research to be undertaken is the synthesis of hetero-annulated glucose derivatives. In particular the synthesis of five-, six-, and seven- and eight-membered N-containing fused heterocycles is desired, with the nitrogen attached at the C-2 and C-3 position of the sugar ring. Emphasis is placed upon using the sugar ring as a scaffold to enable diastereoelective synthesis. A variety of synthetic techniques are to be employed to achieve ring-closure, especially reductive lamination, ring-closing metathesis and photochemical methods of annulation. (Fig. 9206A).;Such compounds could be useful as precursors to alkaloid synthesis due to the huge range of methods for the conversion of pyranosides to other ring systems. In addition, previous work has shown that such compounds have an inhibitory effect on glycoside processing enzymes. The pyrollidines synthesised have been tested as Glycosidase inhibitors, and some have been shown to be weak specific beta-Galactosidase inhibitors.;Using similar techniques as those employed to produce the lactam above, 2,O- and 3,O-fused lactones were also produced, with dimerised by-products also isolated. Intramolecular photocyclisation was also employed to produce complex multicyclic fused carbocyles. (Fig. 9206B).;Synthesis of N-linked amino sugar dimers was also achieved, and initial attempts at deprotection made. (Fig. 9206C).