Preparation of Methyl 2,3-Anhydro- and 2,3-O-Sulfinylfuranosides from Unprotected Furanosides Using the Mitsunobu Reaction

Abstract

A new two step procedure for the synthesis of methyl 2,3-anhydro-a-D-lyxofuranoside and methyl 2,3-anhydro-b-D-ribofuranoside from D-xylose involving the intramolecular Mitsunobu reaction is presented. Likewise, methyl 2,3-anhydro-a-L-lyxofuranoside is obtained from L-arabinose. Cyclic sulfites with D-ribo configuration, synthetic equivalents of the corresponding anhydrosugars, are prepared in three steps from D-ribose.

Direct Glycosylation of Unprotected and Unactivated Carbohydrates under Mild Conditions

“…This strong substrate selectivity is not consistent with results obtained by Fischer glycosylation with MeOH . Both yield and anomeric ratios of glycosides formed by our method are dictated by the configuration of the hydroxy groups of d -pentoses deployed.…”

Recent Advances in Transition Metal-Catalyzed Glycosylation

“…253 Additionally, the β-selectivities observed with the ribose substrate are higher than those attained with the Fischer glycosylation of MeOH. 254,255 …”

Amphidinins C–F, Amphidinolide Q Analogues from Marine Dinoflagellate Amphidinium sp.

“…Comparison of NMR data of 2 between methyl pentofuranosides indicated that the sugar was ribofuranose linked via an α-glycosidic bond. 11 Amphidinin D (2) was treated with Dowex (H + ) in MeOH, and the resulting mixture was esterified with (R)-MTPACl to obtain the tris-(S)-MTPA ester (7a) of a sugar moiety and the (S)-MTPA ester (8a) of an aglycon of 2 (Scheme 2). The 1 H NMR spectra of 7a and 8a were coincident with those of the tris-(S)-MTPA ester of methyl D-ribofuranoside and the (S)-MTPA ester of 1, respectively.…”

“…Analyses of 2D NMR data revealed that 2 was the 4- O -pentofuranoside of 1 (Figure ). Comparison of NMR data of 2 between methyl pentofuranosides indicated that the sugar was ribofuranose linked via an α-glycosidic bond …”