论文信息 - A model for describing the conformations of flexible 6-membered rings—I : The non-chair conformations

A model for describing the conformations of flexible 6-membered rings—I : The non-chair conformations

Abstract An empirical model for calculating the torsional angles for flexible 6-membered rings is presented in terms of three independent parameters, two geometrical and one pseudorotation angle. The rings are classified according to four estimators, the fit of the model depending upon their values. Equations are given for defining any conformation by a point in a 2-dimensional pathway. Some examples have been examined in the light of this model.

[1] C. Altona,et al. Conformation of non-aromatic ring Compounds—XXV: Geometry and conformation of ring D in some steroids from X-ray structure determinations , 1968 .

[2] G. Kartha,et al. The crystal and molecular structures of 4‐bromoestradiol , 1964 .

[3] M. Sundaralingam,et al. Crystal structure of methyl 2,6-dichloro-2,6-dideoxy-3,4- O -isopropylidene-α-D-altropyranoside. A pyranoside system close to a skew-boat conformation , 1973 .