A relationship between estrogenicity and antifertility activity of 1-diphenylmethylenyl-2-methyl-3-ethyl-4-acetoxycyclohexane (ORF 8511) and similar nonsteroidal anti-implantive agents

Yuehchukene, a Novel Anti-implantation Indole Alkaloid fromMurraya paniculata

“…Therefore, having obtained a potent anti-implantation compound based on a novel molecular design, our pertinent question is whether or not yuehchukene can be active in human. It is well known that a serious limitation of using rats as an anti-implantation assay model is that this rodent species is particularly susceptible to estrogen action (9). While preliminary anti-implantation studies in hamster and mice also yielded positive results, albeit at a higher dose level, in-depth evaluation of yuehchukene estrogenicity is now in progress.…”

“…While preliminary anti-implantation studies in hamster and mice also yielded positive results, albeit at a higher dose level, in-depth evaluation of yuehchukene estrogenicity is now in progress. At this moment, suffice it to say that yuehchukene is different from other nonsteroidal anti-implantation agents by the absence of oxygen function (9,10,11,12). Liver transformation of yuehchukene into an estrogenic compound, as in the case of ORF-4563, would require hydroxylation on two sites that would make yuehchukene resemble estradiol (13).…”

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Yuehchukene,9u,8,9,3-blindole, a novel dimeric indole alkaloid from the roots of Murraya paniculata has potent anti-implantation activity in rats at 3 mg/kgp.o. dosing on pregnancy day 2.

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17.alpha.-Ethyl-20.alpha.- and -20.beta.-dihydroprogesterones and other 17.alpha.-ethyl-substituted pregnanes as potential contragestational agents

“…Biological Activity. Contragestational studies were carried out by the procedures described by Hahn et al 19 with the following modifications. Compounds were administered orally to five rats on days 1-6 of gestation (the presence of sperm in vaginal washings constitutes day 1 of gestation) for studies related to effects on implantation or on days 9-12 of gestation for examination of drug effects on pregnancy after implantation.…”