title: 2-Propynyl 2,3,4,6-tetra-O-acetyl-α-D-mannopyranoside.
abstract: The 2-propynyl group in the title compound, C(17)H(22)O(10), adopts an exoanomeric conformation, with the acetylenic group gauche with respect to position C1. Comparison of (13)C NMR chemical shifts from solution and the solid state suggest that the acetylenic group also adopts a conformation anti to C1 in solution. The pyranose ring adopts a (4)C(1) conformation. Of the three secondary O-acetyl groups, that on position O4, flanked by two equatorial groups, adopts a syn conformation, in agreement with recent generalizations [González-Outeiriño, Nasser & Anderson (2005). J. Org. Chem. 70, 2486-2493]. The acetyl group on position O3 adopts a gauche conformation, also in agreement with the recent generalizations, but that on position O2 adopts a syn conformation, not in agreement with the recent generalizations.
authors.affiliation: Applied Chemical Sciences, Jordan University of Science and Technology, Irbid, Jordan.
authors.forename: Hussein
authors.initials: H
authors.lastname: Al-Mughaid
authors.forename: Katherine N
authors.initials: KN
authors.lastname: Robertson
authors.forename: Ulrike
authors.initials: U
authors.lastname: Werner-Zwanziger
authors.forename: Michael D
authors.initials: MD
authors.lastname: Lumsden
authors.forename: T Stanley
authors.initials: TS
authors.lastname: Cameron
authors.forename: T Bruce
authors.initials: TB
authors.lastname: Grindley