Retroprogesterone, also known as 9β,10α-progesterone or as 9β,10α-pregn-4-ene-3,20-dione, is a

progestin A progestogen, also referred to as a progestagen, gestagen, or gestogen, is a type of medication which produces effects similar to those of the natural female sex hormone progesterone in the body. A progestin is a '' synthetic'' progestogen. ...

which was never marketed. It is a stereoisomer of the

naturally occurring A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical ...

progestogen

progesterone Progesterone (; P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the ma ...

, in which the

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

atom at the 9th carbon is in the α-position (below the plane) instead of the β-position (above the plane) and the

methyl group In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated a ...

at the 10th carbon is in the β-position instead of the α-position. In other words, the atom positions at the two carbons have been reversed relative to progesterone, hence the name ''retro''progesterone. This reversal results in a "bent" configuration in which the plane of rings A and B is orientated at a 60° angle below the rings C and D. This configuration is ideal for interaction with the progesterone receptor, with retroprogesterone binding with high

affinity Affinity may refer to: Commerce, finance and law * Affinity (law), kinship by marriage * Affinity analysis, a market research and business management technique * Affinity Credit Union, a Saskatchewan-based credit union * Affinity Equity Pa ...

to this receptor. However, the configuration is not as ideal for binding to other steroid hormone receptors, and as a result, retroprogesterone derivatives have increased selectivity for the progesterone receptor relative to progesterone. Retroprogesterone is the parent compound of a group of progestins consisting of the marketed progestins dydrogesterone (6-dehydroretroprogesterone) and trengestone (1,6-didehydro-6-chlororetroprogesterone) and the never-marketed progestin Ro 6-3129, as well as the active metabolites of these progestins like 20α-dihydrodydrogesterone and 20α-dihydrotrengestone (i.e., the 20α- hydroxylated analogues).

Chemistry

References

Abandoned drugs Diketones Pregnanes Progestogens {{Genito-urinary-drug-stub

Chemistry

See also

References