Cymegesolate (developmental code name Progestin No. 1), also known as cypionyl megestrol acetate or as megestrol acetate 3β-cypionate, 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. Pro ...

medication which was never marketed.Chi-ming, L. (1983). New Long Acting Contraceptive Progestagen Studies on Synthesis of “Cymegesolate” Reproduction & Contraception, 4, 011.Hui-ling, Y. Y. C. C., & Jin-fen, S. (1982). Key Words: Long-acting Progestogen Contraceptive 3-Cyclopentyl Propionate of Megestrol Acetate (Progestin No. 1), Pharmacology, Rabbits; Pharmacological Study on a Long-Acting Progestogen Contraceptive 3-Cyclopentyl Propionate of Megestrol Acetate (Progestin No. 1) Reproduction & Contraception, 4.Xue-jing, W. J. Z. Y., & Mo-zhen, W. (1983). Clinical Study of a Long-Acting Progestogen Contraceptive 3-Cyclopentyl Propionate of Megestrol Acetate (Progestin No. 1) Reproduction & Contraception, 2, 009. It was developed in

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...

in the late 1970s and early to mid 1980s for use as a

hormonal contraceptive Hormonal contraception refers to birth control methods that act on the endocrine system. Almost all methods are composed of steroid hormones, although in India one selective estrogen receptor modulator is marketed as a contraceptive. The origi ...

. The medication was formulated at a dose of 50–100 mg in combination with a "trace" dose of 0.25–0.5 mg

quinestrol Quinestrol, also known as ethinylestradiol cyclopentyl ether (EECPE), sold under the brand name Estrovis among others, is an estrogen medication which has been used in menopausal hormone therapy, hormonal birth control, and to treat breast cancer ...

as a long-lasting, once-a-month

combined oral contraceptive pill The combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as "the pill", is a type of birth control that is designed to be taken orally by women. The pill contains two important hormones: proges ...

. This combination has been studied in 1,213 women across a total of 9,651

menstrual cycle The menstrual cycle is a series of natural changes in hormone production and the structures of the uterus and ovaries of the female reproductive system that make pregnancy possible. The ovarian cycle controls the production and release of eggs ...

s, with contraceptive effectiveness of over 99.13% and "very few

side effect In medicine, a side effect is an effect, whether therapeutic or adverse, that is secondary to the one intended; although the term is predominantly employed to describe adverse effects, it can also apply to beneficial, but unintended, consequence ...

s." At the high dose (100 mg / 0.5 mg), it showed an anovulation rate of only about 60%, and instead mediated its contraceptive effects via a marked anti-implantation effect.

Chemistry

Cymegesolate, also known as megestrol acetate 3β-cypionate, as well as 17α-acetoxy-6-dehydro-6-methylprogesterone 3β-cyclopentylpropionate or 17α-acetoxy-6-methylpregna-4,6-diene-3,20-dione 3β-cyclopentylpropionate, is a

synthetic Synthetic things are composed of multiple parts, often with the implication that they are artificial. In particular, 'synthetic' may refer to: Science * Synthetic chemical or compound, produced by the process of chemical synthesis * Synthetic ...

pregnane Pregnane, also known as 17β-ethylandrostane or as 10β,13β-dimethyl-17β-ethylgonane, is a C21 steroid and, indirectly, a parent of progesterone. It is a parent hydrocarbon for two series of steroids stemming from 5α-pregnane (originally allop ...

steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and ...

and a

derivative In mathematics, the derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value). Derivatives are a fundamental tool of calculus. ...

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 majo ...

and

17α-hydroxyprogesterone 17α-Hydroxyprogesterone (17α-OHP), also known as 17-OH progesterone (17-OHP), or hydroxyprogesterone (OHP), is an endogenous progestogen steroid hormone related to progesterone. It is also a chemical intermediate in the biosynthesis of many o ...

. It is the C3β cypionate (cyclopentylpropionate)

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ...

megestrol acetate Megestrol acetate (MGA), sold under the brand name Megace among others, is a progestin medication which is used mainly as an appetite stimulant to treat wasting syndromes such as cachexia.https://www.accessdata.fda.gov/drugsatfda_docs/label/2014/ ...

. A closely related medication is

acetomepregenol Acetomepregenol (ACM), also known as mepregenol diacetate and sold under the brand name Diamol, is a progestin medication which is used in Russia for the treatment of gynecological conditions and as a method of birth control in combination with ...

(mepregenol diacetate; also known as megestrol 3β,17α-diacetate), which, in contrast, has been marketed.

References

{{Progesterone receptor modulators Abandoned drugs Acetate esters Carboxylate esters Conjugated dienes Cyclopentanes Hormonal contraception Ketones Pregnanes Prodrugs Progestogens