Synthesis of a d-Glucopyranosyl Azide: Spectroscopic Evidence for Stereochemical Inversion in the S_N2 Reaction

Abstract

Stereospecific S N 2 conversion of configurationally pure acetobromoglucose (2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide) to the corresponding β-Dglucopyranosyl azide is a useful exercise in the advanced organic undergraduate teaching laboratory. The procedure is safe and suitable for small-scale implementation, and firm proof of the stereochemical change is obtained from 1 H NMR coupling constants. The exercise provides students with experience in using important chiral pool natural product derivatives, reaction analysis by TLC, as well as careful product isolation, purification, and spectroscopic identification.

Flavonoid Glycosides with a Triazole Moiety for Marine Antifouling Applications: Synthesis and Biological Activity Evaluation

“…Crystallization of the solid with ethanol afforded 2,3,4,6-tetra-O-acetyl- α -D-glucopyranosyl azide 12 with 72% yield. The structure elucidation was established by 1 H and 13 C NMR techniques and data were in accordance with previously reported results [ 27 ].…”

“…The 2,3,4,6-tetra- O -acetyl-β-D-glucopyranosyl azide ( 12 ), used as a building block for the synthesis of glycosylated derivatives 3a , 3b , 7a and 7b , was synthesized from 2,3,4,6-tetra- O -acetyl-α-D-glucopyranosyl bromide and sodium azide, as described by Adesoye et al [ 27 ], with 72% yield.…”

Synthesis and Cytotoxic Activity of New 1,3,4-Thiadiazole Thioglycosides and 1,2,3-Triazolyl-1,3,4-Thiadiazole N-glycosides

“…The cytotoxic activity of the synthesized compounds was studied at National Research Center, Cairo, Egypt. The glycosyl azides were prepared as previously reported [37,38].…”

Organoboron-Promoted Regioselective Glycosylations in the Synthesis of a Saponin-Derived Pentasaccharide from Spergularia ramosa

“…NMR spectral data were in agreement with those reported previously. 37 n-Pentenyl α-L-Rhamnopyranoside. 20 Acetic anhydride (15.0 mL, 160 mmol) was added to a solution of L-rhamnose (3.30 g, 20.0 mmol) in pyridine (20.0 mL) and stirred at overnight.…”