Pre-activation of fully acetylated dodecyl thioglycosides with BSP–Tf2O led to efficient glycosylation at low temperature
摘要:
Fully acetylated dodecyl thioglycosides were found to be useful as glycosyl donors by activation with 1-benzenesulfinyl piperidine (BSP) and triflic anhydride (Tf2O) at -78 degrees C. The glycosyl acceptor was added to the reaction mixture at the same temperature to furnish various disaccharide, including the protected Lewis a (Le(a)) trisaccharide, in good yields. (C) 2008 Elsevier Ltd. All rights reserved.
Synthesis of a tetrasaccharide repeating unit of O-antigenic polysaccharide of Salmonella enteritidis by use of unique and odorless dodecyl thioglycosyl donors
The first total synthesis of a unique tetrasacchariderepeatingunit of lipopolysaccharide fromSalmonella enteritidis has been accomplished by assembly of dodecyl thioglycosides. The crucial key steps were preparation of a rare branched dideoxy sugar, d-tyvelose (3,6-dideoxy-d-arabino-d-hexose) and sequential regioselective glycosylation at 2,3-positions of a central d-mannose residue 5 with d-tyvelose