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Conformational analysis of model compounds of vitamin D by theoretical calculations

✍ Scribed by Mart�nez-N��ez, Emilio; V�zquez, Saulo A.; Mosquera, Ricardo A.

Publisher
John Wiley and Sons
Year
1997
Tongue
English
Weight
211 KB
Volume
18
Category
Article
ISSN
0192-8651

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✦ Synopsis

A conformational analysis of two model compounds of vitamin D was carried out by means of theoretical computations, Ab initio calculations Ž . were carried out using the standard 6-31G* basis set at the Hartree᎐Fock HF Ž . level of theory. In addition, the Møller᎐Plesset MP2 correlation treatment was applied on the simplest model. Semiempirical calculations were also performed using the AM1 Hamiltonian. The results predict stable A-ring twist forms with energies in the order of 4᎐6 kcalrmol relative to the global minimum, significantly higher than those reported from molecular mechanics calculations. In addition, a folded conformation was found by the HF optimizations; however, its stability is predicted to be very poor. Comparison of the theoretical results with experimental data is discussed.

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