Stereocontrolled synthesis of D- and L-beta-rhamnopyranosides with 4-O-6-S-alpha-cyanobenzylidene-protected 6-thiorhamnopyranosyl thioglycosides.
The synthesis of both enantiomers of a 4-O-6-S-alpha-cyanobenzylidene-protected 6-thiorhamnopyranosyl thioglycoside is described starting from D-mannnose and L-arabinose derivatives for the D- and L-series, respectively. This donor is effective in the preparation of the corresponding beta-glycosides using the 1-benzenesulfinyl piperidine/trifluoromethanesulfonic anhydride protocol. Following desulfurization and concomitant debenzylation with Raney nickel, the so-formed 6-thio-beta-mannosides are converted in high yield to the beta-rhamnopyranosides.
Crich
David
D
Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, USA. dcrich@icsn.cnrs-gif.fr
Li
Linfeng
L
D000080:Acetals / Q000737:chemistry; D009570:Nitriles / Q000737:chemistry*; D012210:Rhamnose / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013379:Substrate Specificity; D013455:Sulfur / Q000737:chemistry; D013865:Thioglycosides / Q000737:chemistry*
D000080:Acetals; D009570:Nitriles; D013865:Thioglycosides; D013455:Sulfur; D012210:Rhamnose