Document Type

Article

Publication Date

10-2001

Journal or Book Title

Carbohydrate Research

Volume

335

Issue

4

First Page

261

Last Page

273

DOI

10.1016/S0008-6215(01)00240-3

Abstract

Extensive variations of the ring structures of three deoxyaldohexopyranoses, l-fucose, d-quinovose, and l-rhamnose, and four dideoxyaldohexopyranoses, d-digitoxose, abequose, paratose, and tyvelose, were studied by energy minimization with the molecular mechanics algorithm MM3(92). Chair conformers, 4C1 ind-quinovose and the equivalent 1C4 in l-fucose and l-rhamnose, overwhelmingly dominate in the three deoxyhexoses; in the d-dideoxyhexoses, 4C1 is again dominant, but with increased amounts of 1C4 forms in the α anomers of the three 3,6-dideoxyhexoses, abequose, paratose, and tyvelose and in both α and β anomers of the 2,6-dideoxyhexose d-digitoxose. In general, modeled proton–proton coupling constants agreed well with experimental values. Computed anomeric ratios strongly favor the β configuration except ford-digitoxose, which is almost equally divided between α and β configurations, and l-rhamnose, where the β configuration is somewhat favored. MM3(92) appears to overstate the prevalence of the equatorial β anomer in all three deoxyhexoses, as earlier found with fully oxygenated aldohexopyranoses.

Comments

This is a post-print of an article from Carbohydrate Research, 335, no. 4 (October 2001): 261–273, doi: 10.1016/S0008-6215(01)00240-3.

Copyright Owner

Elsevier Science Ltd.

Language

en

File Format

application/pdf

Share

COinS