Pentagestrone acetate (PGA), sold under the brand names Gestovis and Gestovister, 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 described in the literature in 1960 and was introduced by Vister in

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

in 1961. It is the 3-

cyclopentyl Cyclopentane (also called C pentane) is a highly flammable alicyclic hydrocarbon with chemical formula C5H10 and CAS number 287-92-3, consisting of a ring of five carbon atoms each bonded with two hydrogen atoms above and below the plane. It is a ...

enol ether In organic chemistry an enol ether is an alkene with an alkoxy substituent. The general structure is R2C=CR-OR where R = H, alkyl or aryl. A common subfamily of enol ethers are vinyl ethers, with the formula ROCH=CH2. Important enol ethers incl ...

of 17α-hydroxyprogesterone acetate. PGA, along with quingestrone (the 3-cyclopentyl enol ether of progesterone), is said to have very similar properties to those of

dydrogesterone Dydrogesterone, sold under the brand name Duphaston among others, is a progestin drug, medication which is used for a variety of indications, including miscarriage, threatened or recurrent miscarriage during pregnancy, dysfunctional bleeding, i ...

, a pure

progestogen Progestogens, also sometimes written progestins, progestagens or gestagens, are a class of natural or synthetic steroid hormones that bind to and activate the progesterone receptors (PR). Progesterone is the major and most important progestoge ...

and close analogue of progesterone. PGA is orally active, was provided in 10 and 20 mg capsules, and has been used to treat habitual abortion and

menstrual disorder A menstrual disorder is characterized as any abnormal condition with regards to a woman's menstrual cycle. There are many different types of menstrual disorders that vary with signs and symptoms, including pain during menstruation, heavy bleeding, ...

s at a dosage of 10 to 20 mg/day. It has been said to have equivalent

potency Potency may refer to: * Potency (pharmacology), a measure of the activity of a drug in a biological system * Virility * Cell potency, a measure of the differentiation potential of stem cells * In homeopathic dilutions, potency is a measure of ho ...

intramuscular Intramuscular injection, often abbreviated IM, is the injection of a substance into a muscle. In medicine, it is one of several methods for parenteral administration of medications. Intramuscular injection may be preferred because muscles hav ...

progesterone. The combination of 20 mg/day PGA and 100 μg/day

mestranol Mestranol, sold under the brand names Enovid, Norinyl, and Ortho-Novum among others, is an estrogen medication which has been used in birth control pills, menopausal hormone therapy, and the treatment of menstrual disorders. It is formulated in ...

is an effective

ovulation Ovulation is an important part of the menstrual cycle in female vertebrates where the egg cells are released from the ovaries as part of the ovarian cycle. In female humans ovulation typically occurs near the midpoint in the menstrual cycle and ...

inhibitor in women. The effective dosage of PGA in the menstrual delay test has been studied.

Chemistry

PGA, also known as 17α-acetoxyprogesterone 3-cyclopentyl enol ether, is a

synthetic Synthetic may refer to: Science * Synthetic biology * Synthetic chemical or compound, produced by the process of chemical synthesis * Synthetic elements, chemical elements that are not naturally found on Earth and therefore have to be created in ...

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 all ...

steroid A steroid is an organic compound with four fused compound, fused rings (designated A, B, C, and D) arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes t ...

and a

derivative In mathematics, the derivative is a fundamental tool that quantifies the sensitivity to change of a function's output with respect to its input. The derivative of a function of a single variable at a chosen input value, when it exists, is t ...

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 ...

and 17α-hydroxyprogesterone.

References

Abandoned drugs Acetate esters Cyclopentyl ethers Ethers Pregnanes Progestogen esters Progestogen ethers Progestogens {{Steroid-stub

Chemistry

See also

References