The crystal and molecular structure of d-norgestrel, a progestational steroid

A full conformational characterization of 13-ethylprogestogens through theoretical calculations and nuclear magnetic resonance spectroscopy

“…In all the cases the preferred one is the same (τ OH about 165 • ), in agreement with the orientation found in the X-ray structure of 17-ethynyl-17-hydroxysteroids [15][16][17][18].…”

Structure of modifications (I) and (II) of 13-ethyl-17β-hydroxy-18,19-dinor-17α-pregna-4,15-dien-20-yn-3-one (gestodene)

“…The structure differs from levonorgestrel, which has been used for a long time in oral contraception, by the introduction of a A ~5 unsaturation. In order to enable a better understanding of the structure--activity relationships of the progestogens the 3D structure of gestodene has been determined by X-ray diffraction and its molecular conformation is compared with that of levonorgestrel (DeAngelis, Doyne & Grob, 1975 dimensions. Cleve, Frost, Hoyer, Rosenberg & Seeger (1986) studied the structure of gestodene by spectroscopic methods.…”

“…For modification (I) initial phases were obtained from tangent refinement of phases calculated with the coordinates of the isomorphous crystal structure of levonorgestrel (DeAngelis, Doyne & Grob, 1975;Crabb~ & Schlemper, 1983). The structure of (II) was solved by direct methods by default run with the SHELXS86 program (Sheldrick, 1986).…”

Totalsynthese von (–)‐Norgestrel

“…fur C,,H2,03 (314,4): C 76,40,H 8,33;gef. : C 76,18,H 8,17. Fraktionen mit den anderen Isomeren wurden vereinigt und nochmals der prap. HPLC sowie anschliessender Kugelrohrdestillation unterworfen: 0,18 g (9%) 12a.…”