A novel approach towards the stereoselective synthesis of 2-azido-2-deoxy-β-d-mannosides
摘要:
Low temperature mannosylation of glycosyl acceptors under the agency of S-(4-methoxyphenyl) benzenethiosulfinate (MPBT) and trifluoromethanesulfonic anhydride (Tf2O) with p-methoxyphenyl 2-azido-3-O-benzyl-4,6-O-benzylidene-2-deoxy-1-thio-alpha -D-mannopyranoside, readily available from D-mannosamine hydrochloride, affords 2-azido-2-deoxy-D-mannosides with high beta -selectivity in good yields. (C) 2001 Elsevier Science Ltd. All rights reserved.
An Expedient Synthesis of the Repeating Unit of the Acidic Polysaccharide of the Bacteriolytic Complex of Lysoamidase
作者:Remy E. J. N. Litjens、Ren� den Heeten、Mattie S. M. Timmer、Herman S. Overkleeft、Gijsbert A. van der Marel
DOI:10.1002/chem.200400862
日期:2005.1.21
The first synthesis of the trisaccharide repeatingunit of the acidicpolysaccharide of the bacteriolyticcomplex of lysoamidase is presented. The construction is based on a linear glycosylation strategy that starts from the reducing end and employs thio- and selenoglycosides in a highly stereoselective manner by a single set of activation conditions. The thus-formed trisaccharide is selectively deprotected