Application of Dichlorovinyl Xyloside for the Novel Synthesis of 2,3,4‐Tri‐O‐methyl‐D‐xylono‐1,5‐lactone

Abstract

A novel synthesis of 2,3,4-tri-O-methyl-D-xylopyranose, 4, and its oxidation product 2,3,4-tri-O-methyl-D-xylono-1,5-lactone, 5, are reported. The new synthesis applies a regioselective Wittig-like reaction of tetra-O-acetyl-D-xylopyranase, 1, with triphenylphosphine and carbon tetrachloride to yield an O-dichlorovinyl xyloside protected at C-1, 2. The protecting group facilitates the permethylation of xylose and is removed under the methylation conditions, to yield tetra-O-acetyl-D-xylopyranase, 3. The anomeric methyl group was removed under mildly acidic conditions to give 2,3,4-tri-O-methyl-D-xylopyranose, 4, in good yield. Compound 4 was oxidized using pyridinium chlorochromate to give the title compound, 5, in 95% yield.

Chemistry of xylopyranosides

“…Pyranose oxidase, isolated from mycelium extracts of the fungi basidiomycota, oxidized [310][311] or when the xylosides were treated with bromine in the presence of NaBO2. 312 2,3,4-Tri-O-protected xylopyranoses were oxidized at the anomeric position by treatment with Ac2O/DMSO, 137 PCC, 138,313 or TPAP/NMO 314 to form the corresponding δlactones 71. Oxidizing D-xylose using cupric acetate generated 72 in 50-55% yield.…”