2,3,4,6-Tetra-O-benzyl-D-glucopyranose is an important D-glucopyranose derivative, which is often used as a pharmaceutical intermediate in the synthesis of derivatives for the treatment of Alzheimer's disease, diabetes, and cancer.
2,3,4,6-Tetra-O-benzyl-D-glucopyranose (cas# 4132-28-9) is a compound useful in organic synthesis. For example, it enables the preparation of α-glucopyranosyl chloride as well as 1-C-α-D-glucopyranosyl derivatives; it can also be used in the preparation of important D-glucopyranosyl derivatives for glucosylation and other reactions.
After activation with trifluoroacetic anhydride, 2,3,4,6-Tetra-O-benzyl-D-glucopyranose reacts with various silyl enol ethers or allyl silanes in the presence of Lewis acids to generate α-configured C-D-glucopyranosyl derivatives, and reacts with activated aromatic nucleophiles to generate the corresponding β-anomers[2]. It can also be used to synthesize the antibiotic (+)-nojirimycin[3].
The coupling reaction of 2,3,4,6-tetra-O-benzyl-1-C-phenyl-α-D-glucopyranose with 2,3,4,6-tetra-O-benzyl-D-glucopyranose, in the presence of 5 mol% bismuth(III) triflate in dichloromethane at 0 °C, could synthesize 2,3,4,6-tetra-O-benzyl-1-C-phenyl-D-glucopyranosyl 2,3,4,6-tetra-O-benzyl-D-glucopyranoside[1].
Add 19.4g of 2,3,4,6-tetra-O-benzyl-β-D-glucosinolate to 500mL of acetone, and add 18.7g of N-bromosuccinyl in batches with stirring Imine (NBS), after the addition, react at 25°C for 0.5h. Most of the acetone was evaporated under reduced pressure, and a white solid was precipitated, which was diluted by adding 200 mL of 1mol/L hydrochloric acid and allowed to stand at -18°C for 3h. After suction filtration, the filter cake was washed with cold absolute ethanol, and recrystallized with absolute ethanol-cyclohexane to obtain 15.6 g of white flocculent solid 2,3,4,6-Tetra-O-benzyl-D-glucopyranose with a yield of 96.6%.
[1] T. Yamanoi, Yoshiki Oda, R. Inoue. “2,3,4,6-Tetra-O-benzyl-1-C-phenyl-α-D-glucopyranosyl 2,3,4,6-Tetra-O-benzyl-α-D-glucopyranoside.” Molbank 35 1 (2012).
[2] P. ALLEVI. The first direct method for C-glucopyranosyl derivatization of 2,3,4,6-tetra-O-benzyl-D-glucopyranose[J]. Journal of The Chemical Society, Chemical Communications, 1987. DOI:10.1039/C39870001245.
[3] STéPHANE MOUTEL M. S. Synthesis of (+)-nojirimycin from 2,3,4,6-tetra-O-benzyl-D-glucopyranose[J]. Journal of The Chemical Society-perkin Transactions 1, 1999. DOI:10.1039/A901811E.
