𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Ring a conformation in steroids. 3—Cyclosteroids and cyclopropanosteroids

✍ Scribed by Kirk Marat; J. F. Templeton; Yangzhi Ling; Weiyang Lin; R. K. Gupta

Publisher
John Wiley and Sons
Year
1995
Tongue
English
Weight
882 KB
Volume
33
Category
Article
ISSN
0749-1581

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

Proton and carbon NMR data are provided for 21 ring A and ring B cyclosteroids and cyclopropano (or methylene) steroids. Shift assignments were made using standard 2D NMR techniques, while ring A proton subspectra were extracted with a 1D TOCSY experiment. Coupling constants were obtained from iterative spin system simulation of these sub‐spectra. Ring A conformations were determined from the two‐ and three‐bond proton‐proton couplings and NOE measurements. The utility and limitations of extended Karplus‐type equations, the effect of cyclopropyl groups on vicinal and geminal couplings and cyclopropane‐induced chemical shifts are discussed.

📜 SIMILAR VOLUMES

The conformation of ring A in 4,4-dimeth
The conformation of ring A in 4,4-dimethyl-3-keto-steroids
✍ Norman L. Allinger; Margaret A. DaRooge 📂 Article 📅 1961 🏛 Elsevier Science 🌐 French ⚖ 258 KB

THE ground state oouformations of the steroid ring systems are in general securely looked in potential wells, can vary but little, and are for the most part well understood. In a 4,4-dimethyl-3-keto-5gC-steroid (I) however, there is reason to question whether or not ring A will be in the standard ch

An NMR study of A-ring conformation in s
An NMR study of A-ring conformation in some 4-en-3-one steroids
✍ Kirk Marat; J. F. Templeton; V. P. Sashi Kumar 📂 Article 📅 1987 🏛 John Wiley and Sons 🌐 English ⚖ 584 KB

NMR spectral data are given for the A-ring in ten 4-en-3-one steroids, and the strategy of the spectral analysis is described. The data are interpreted in terms of an equilibrium between normal and inverted half-chair conformations, with the normal conformation predominant in all cases except when Z

Ring A Aromatic Steroids in the Pregnane
Ring A Aromatic Steroids in the Pregnane Series.
✍ Cavit Uyanik; Aslihan Malay; James R. Hanson; Peter B. Hitchcock; Serpil Tiryaki 📂 Article 📅 2006 🏛 John Wiley and Sons ⚖ 18 KB

## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.