title: Gold(III)-catalyzed glycosidations for 1,2-trans and 1,2-cis furanosides.
abstract: Stereoselective synthesis of furanosides is still a daunting task, unlike the pyranosides, for which several methods exist. Herein, a unified stereoselective strategy for the synthesis of 1,2-trans and 1,2-cis furanosides is revealed for seven out of eight possible isomers of pentoses. The identified protocol gives access to diastereoselective synthesis of α- and β-araf, ribf, lyxf, and α-xylf furanosides. 1,2-trans glycosides were synthesized by the use of propargyl 1,2-orthoesters under gold-catalyzed glycosidation conditions, and subsequently, they are converted into 1,2-cis glycosides through oxidation-reduction as the key functional group transformation. All the reactions are found to be fully diastereoselective, mild, and high yielding.
authors.affiliation: Department of Chemistry, Indian Institute of Science Education and Research , Pune, Maharashtra 411008, India.
authors.forename: Shivaji A
authors.initials: SA
authors.lastname: Thadke
authors.forename: Bijoyananda
authors.initials: B
authors.lastname: Mishra
authors.forename: Srinivas
authors.initials: S
authors.lastname: Hotha
mesh_terms: D002384:Catalysis; D006027:Glycosides / Q000138:chemical synthesis* / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D010084:Oxidation-Reduction; D010429:Pentoses / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D006027:Glycosides; D010429:Pentoses; D006046:Gold