title: Application of 2-substituted benzyl groups in stereoselective glycosylation.
abstract: The use of 2-O-(2-nitrobenzyl) and 2-O-(2-cyanobenzyl) groups controls stereoselective formation of 1,2-trans-glycosidic linkages via the arming participation effect. The observed stereoselectivity likely arises from the intramolecular formation of cyclic intermediate between the electron-rich substituent and the donor oxacarbenium ion providing the expected facial selectivity for attack of the glycoside acceptor. The stereodirecting effect of the 2-nitro- and 2-cyanobenzyl groups attached at the remote position (C-3, C-4, and C-6) of the donor molecule have also been investigated. To prove the postulated mechanism based on the participation effect of 2-substituted benzyl groups in the glycosylation stereoselectivity we used DFT theoretical calculation methodology.
authors.affiliation: Faculty of Chemistry, Jagiellonian University , Ingardena 3, 30-060 Krakow, Poland.
authors.forename: Szymon
authors.initials: S
authors.lastname: Buda
authors.forename: Mirosław
authors.initials: M
authors.lastname: Nawój
authors.forename: Patrycja
authors.initials: P
authors.lastname: Gołębiowska
authors.forename: Karol
authors.initials: K
authors.lastname: Dyduch
authors.forename: Artur
authors.initials: A
authors.lastname: Michalak
authors.forename: Jacek
authors.initials: J
authors.lastname: Mlynarski
mesh_terms: D006027:Glycosides / Q000737:chemistry*; D006031:Glycosylation; D015394:Molecular Structure; D009578:Nitrobenzenes / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D006027:Glycosides; D009578:Nitrobenzenes