Conformational analysis of the anomeric forms of sophorose, laminarabiose, and cellobiose using MM3

• Published in: Carbohydrate research 1992-09, Vol.233, p.15-34
• Main Authors: Dowd, Michael K., French, Alfred D., Reilly, Peter J.
• Format: Article
• Language: English
• Subjects: Atomic and molecular physics; Carbohydrate Conformation; Carbohydrate Sequence; Cellobiose - chemistry; Disaccharides; Exact sciences and technology; Glucans - chemistry; Interatomic distances and angles; Models, Chemical; Molecular properties and interactions with photons; Molecular Sequence Data; Molecular Structure; Physics; Properties of molecules and molecular ions; Stereoisomerism; X-Ray Diffraction
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/S0008-6215(00)90917-0

Relaxed-residue energy maps based on the MM3 force-field were computed for relative orientations of the pyranosyl rings of sophorose, laminarabiose, and cellobiose, respectively the (1 → 2)-β-; (1 → 3)-β-; and (1 → 4)-β-linked- d-glucosyl disaccharides. Sixteen starting conformations of the rotatable exocyclic side-groups were considered for each molecule. All of the energy surfaces have two intersecting low-energy troughs and illustrate the importance of exo-anomeric effects in determining disaccharide conformation. Local minima were found by relaxed minimization without restriction. The energy surfaces of these disaccharides are very similar to the energy surfaces of their corresponding 6-methyl-tetrahydropyran analogues. There is good agreement between disaccharide structures having minimal MM3 energy and those found by crystallography.