Circular dichroism, proton magnetic resonance and conformation of steroid 4-en-3-ones, 4, 9-dien-3-ones and 4, 9, 11-trien-3-ones

Autor:	Vladimir Delaroff, Lucien Nedelec, N. Dupuy, M. Legrand
Rok vydání:	1979
Předmět:	Circular dichroism Stereochemistry Chemistry medicine.medical_treatment Organic Chemistry Ring (chemistry) Biochemistry Relative stability Proton magnetic resonance Steroid Crystallography Drug Discovery medicine Conformational isomerism Dynamic equilibrium
Zdroj:	Tetrahedron. 35:2681-2692
ISSN:	0040-4020
DOI:	10.1016/0040-4020(79)87050-7
Popis:	Room and low-temperature CD of the title dienones and trienones ( 3 to 9 ) clearly show that a conformational equilibrium occurs between two ring A half-chair conformers. The relative stability of the two conformers depends on substitution of ring A. These results may be extended to other series of steroids and in particular to 4-en-3-ones. CD of these enones ( 14 to 28 ) is consistent with a conformational equilibrium between the known quasi- cis -quasi- trans conformers. The controversial conformational behaviour of 2 β-substituted 19-nor-4-en-3-ones is explained by a dynamic equilibrium in solution between the two afore-mentioned conformers rather than by single twist or deformed boat conformer.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::c5e6c3505c87bfc77201ad58dd45a1f3 https://doi.org/10.1016/0040-4020(79)87050-7 Zobrazit plný text záznamu