Polytestosterone phloretin phosphate (PTPP) is an

androgen An androgen (from Greek ''andr-'', the stem of the word meaning "man") is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This in ...

and

anabolic steroid Anabolic steroids, also known more properly as anabolic–androgenic steroids (AAS), are steroidal androgens that include natural androgens like testosterone as well as synthetic androgens that are structurally related and have similar effects ...

as well as

androgen ester An androgen or anabolic steroid ester is an ester of an androgen/anabolic steroid (AAS) such as the natural testosterone or dihydrotestosterone (DHT) or the synthetic nandrolone (19-nortestosterone). Esterification renders AAS into metabolism-re ...

which was never marketed. It is an

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 ...

testosterone Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristi ...

with

phosphoric acid Phosphoric acid (orthophosphoric acid, monophosphoric acid or phosphoric(V) acid) is a colorless, odorless phosphorus-containing solid, and inorganic compound with the chemical formula . It is commonly encountered as an 85% aqueous solution, w ...

that is in the form of a

polymer A polymer (; Greek '' poly-'', "many" + '' -mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic a ...

and is coupled with

phloretin Phloretin is a dihydrochalcone, a type of natural phenol. It can be found in apple tree leaves and the Manchurian apricot. Metabolism In rats, ingested phlorizin is converted into phloretin by hydrolytic enzymes in the small intestine. Phl ...

. Like other androgen esters, PTPP acts as a long-lasting

prodrug A prodrug is a medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be used to improve how the dru ...

of testosterone in the body. However, analogously to the polymeric

estrogen ester An estrogen ester is an ester of an estrogen, most typically of estradiol but also of other estrogens such as estrone, estriol, and even nonsteroidal estrogens like diethylstilbestrol. Esterification renders estradiol into a prodrug of estradiol ...

polyestradiol phosphate Polyestradiol phosphate (PEP), sold under the brand name Estradurin, is an estrogen medication which is used primarily in the treatment of prostate cancer in men. It is also used in women to treat breast cancer, as a component of hormone therapy ...

(PEP),

polyestriol phosphate Polyestriol phosphate (PE3P, SEP), sold under the brand names Gynäsan, Klimadurin, and Triodurin, is an estrogen medication which was previously used in menopausal hormone therapy (i.e., to treat menopausal symptoms in postmenopausal women) an ...

(PE3P), and

polydiethylstilbestrol phosphate Polydiethylstilbestrol phosphate (PSP, PDSP) is an estrogen (medication), estrogen medication which has been used in scientific research and has been studied for use in veterinary medicine as a livestock growth promoter. It is a phosphate ester of ...

(PSP), PTPP has a strongly prolonged duration with very uniform testosterone levels in animals compared to non-polymeric

testosterone ester This is a list of androgen esters, including esters (as well as ethers) of natural androgens like testosterone and dihydrotestosterone (DHT) and synthetic anabolic–androgenic steroids (AAS) like nandrolone (19-nortestosterone). Esters of nat ...

s. According to its developers, this is "exactly the effect which should be aimed at in order to approach natural hormone production as closely as possible". PTPP was developed around 1953 at the same time as PEP and its

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A ...

was published in 1960. The patent was assigned to the

Swedish Swedish or ' may refer to: Anything from or related to Sweden, a country in Northern Europe. Or, specifically: * Swedish language, a North Germanic language spoken primarily in Sweden and Finland ** Swedish alphabet, the official alphabet used by ...

pharmaceutical company The pharmaceutical industry discovers, develops, produces, and markets drugs or pharmaceutical drugs for use as medications to be administered to patients (or self-administered), with the aim to cure them, vaccinate them, or alleviate sympt ...

Leo Läkemedel AB, which also developed PEP. PEP is a linear polymer of on average 13

repeat unit In polymer chemistry, a repeat unit or repeating unit (or mer) is a part of a polymer whose repetition would produce the complete polymer chain (except for the end-groups) by linking the repeat units together successively along the chain, like the ...

s of estradiol phosphate. Each individual

estradiol Estradiol (E2), also spelled oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of the estrous and menstrual female reproductive cycles. Estradiol is responsible for the development o ...

unit in the molecule is connected by its C3 and C17β

hydroxyl group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...

s to

linkers that are present between the estradiol moieties. In contrast to estradiol, such a polymer is not possible with testosterone because testosterone has only one hydroxyl group and hence does not have the two hydroxyl groups necessary for linking the testosterone units together. In PTPP, phloretin is used as a coupling agent to solve this problem and create a testosterone phosphate polymer. Phloretin has four available hydroxyl groups present in its chemical structure. A linear polymer of phloretin with phosphoric acid linkers is present as the

backbone The backbone is the vertebral column of a vertebrate. Arts, entertainment, and media Film * ''Backbone'' (1923 film), a 1923 lost silent film starring Alfred Lunt * ''Backbone'' (1975 film), a 1975 Yugoslavian drama directed by Vlatko Gilić ...

of the molecule, and testosterone moieties are connected to the free third and fourth hydroxyl groups of each phloretin unit also with phosphoric acid linkers. As such, two testosterone moieties essentially "hang" or "dangle off" of each phloretin unit in the polymer, and these testosterone moieties are slowly cleaved from the polymer.

References

Abandoned drugs Androgens and anabolic steroids Androstanes Copolymers Dihydrochalcones Phosphate esters Testosterone esters {{Steroid-stub

See also

References