Deciphering the conformational preferences of furanosides. A molecular dynamics study

Side Chain Conformation and Its Influence on Glycosylation Selectivity in Hexo- and Higher Carbon Furanosides

“…More recently, Wang and Woods also found in the course of a molecular dynamics study that the ring conformations of simple pentofuranosides are influenced by side chain conformation . In contrast, in a subsequent molecular dynamics study, Nester and Plazinski found very little correlation between ring and side chain conformation in the pentofuranosides, with differences of ≤0.7 kcal·mol –1 in the arabino and ribofuranosides …”

“…23 In contrast, in a subsequent molecular dynamics study, Nester and Plazinski found very little correlation between ring and side chain conformation in the pentofuranosides, with differences of ≤0.7 kcal•mol −1 in the arabino and ribofuranosides. 24 We begin this article with a brief survey of literature hexofuranosides for which sufficiently detailed NMR spectral or X-ray crystallographic data are available to provide a preliminary assessment of side chain conformation before proceeding to the synthesis of a series of diastereomeric 6deoxyhexofuranosyl donors, the analysis of their side chain conformation and the influence of the side chain conformation on reactivity and selectivity at the anomeric center. We show that the model developed for the correlation of configuration with side chain conformation in the higher carbon pyranoses holds for the higher carbon furanoses but that other factors also impinge on the reactivity and selectivity of the furanosyl donors.…”

Characteristic 1H NMR spectra of β-d-ribofuranosides and ribonucleosides: factors driving furanose ring conformations

“…It is important to add that the three factors influencing the conformation of the furanose ring listed herein were also noticed in molecular dynamics studies. 80 …”

“…It is important to add that the three factors inuencing the conformation of the furanose ring listed herein were also noticed in molecular dynamics studies. 80 Apart from the endo-anomeric effect, an exo-anomeric effect can also act in the sugar ring. This is caused by the exocyclic oxygen atom from the aglycone and means that the gauche orientation is preferred over the antiperiplanar orientation in the O5-C1-O1-C7 (pyranose) or O4-C1-O1-C6 (furanose) atoms arrangement (Fig.…”