Sulfonamidoglycosylation of Methyl Glycosides Employing Perchloric Acid Supported on Silica Gel
摘要:
The sulfonamidoglycosylation of methyl glycosides in the presence of perchloric acid immobilized on silica gel proceeded effectively to afford the corresponding sulfonamido glycosides with good to high yields with minimal workup and short reaction times. This methodology was applied to the synthesis of some N-glycosyl sulfamides, which showed low nanomolar activity against human carbonic anhydrase.
[EN] PROCESS FOR THE SYNTHESIS OF 2-DEOXY-D-GLUCOSE<br/>[FR] PROCESSUS DE SYNTHESE DE DEOXY-D-GLUCOSE
申请人:COUNCIL SCIENT IND RES
公开号:WO2004058786A1
公开(公告)日:2004-07-15
The present invention provides a process for the synthesis of 2-deoxy-D-glucose comprising haloalkoxylation of R-D-Glucal wherein R is selected from H and 3, 4, 6-tri-O-benzyl, to obtain alkyl 2-deoxy-2-halo-R-α/β-D-gluco/mannopyranoside, converting alkyl 2-deoxy-2-halo-R-α/$(b)-D-gluco/mannopyranoside by reduction to alkyl 2-deoxy-α/$(b)-D-glucopyranoside, hydrolysing alkyl 2-deoxy-α/$(b)-D-glucopyranoside to 2-deoxy-D-glucose.
Tri-O-benzyl-d-glycal treated with per-O-benzyl-2-deoxy-α- or per-O-benzyl-2-deoxy-β-d-glycosyl hydroperoxide affords the corresponding bisglycosyl peroxides. In all cases a new α-glycosidic bond is formed. Formation of the peroxide is not a reversible process; under applied reaction conditions, we did not observe rearrangement of β,α-peroxide into the corresponding α,α-compounds.
Aluminium triflate catalysed O-glycosidation: temperature-switched selective Ferrier rearrangement or direct addition with alcohols
作者:D. Bradley G. Williams、Sandile B. Simelane、Henok H. Kinfe
DOI:10.1039/c2ob25540e
日期:——
A temperature-controlled mechanism switch between the Al(OTf)3-catalysed direct addition of alcohols or the Ferrier rearrangement reactions in some glycals is presented. The scope and limitations are investigated as are the influence of the stereochemistry and nature of the protecting groups on the glycal substrate.
The present invention provides a process for the synthesis of 2-deoxy-D-glucose comprising haloalkoxylation of R-D-Glucal wherein R is selected from H and 3, 4, 6-tri-O-benzyl, to obtain alkyl 2-deoxy-2-halo-R-&agr;/&bgr;-D-gluco/mannopyranoside, converting alkyl 2-deoxy-2-halo-R-&agr;/&bgr;-D-gluco/mannopyranoside by reduction to alkyl 2-deoxy-&agr;/&bgr;-D-glucopyranoside, hydrolysing alkyl 2-deoxy-&agr;/&bgr;-D-glucopyranoside to 2-deoxy-D-glucose.