A summary of the most common chemical descriptors (InChI Key and SMILES codes) for Tetrahydrogestrinone are summarized together with 3D and 2D structures and relevant physico-chemical properties.

What is the Tetrahydrogestrinone?

The molecule Tetrahydrogestrinone presents a molecular formula of C21H28O2 and its IUPAC name is (8S,13S,14S,17S)-13,17-diethyl-17-hydroxy-1,2,6,7,8,14,15,16-octahydrocyclopenta[a]phenanthren-3-one.

Tetrahydrogestrinone (THG) is a synthetic, orally active progestin and androgen that was designed by G. D. Searle & Company. It was never marketed. THG has potent progestogenic, androgenic, and antigonadotropic activity. In addition, it is a potent agonist of the progesterone receptor (PR) and a partial agonist of the androgen receptor (AR). It is also a very potent inhibitor of 5α-reductase. THG is about 10-fold more potent than levonorgestrel as a PR agonist, and about as potent as levonorgestrel in terms of androgenic and antigonadotropic activity. The EC50 values of THG for the AR and PR are 0.13 nM and 0.016 nM, respectively. The binding affinity of THG for the SHBG is very high, with an affinity constant (Ki) of 0.02 nM..

3D structure

Cartesian coordinates

Geometry of Tetrahydrogestrinone in x, y and z coordinates (Å units) to copy/paste elsewhere. Generated with Open Babel software.

2D drawing


Tetrahydrogestrinone OXHNQTSIKGHVBH-ANULTFPQSA-N chemical compound 2D structure molecule svg


Molecule descriptors

IUPAC name(8S,13S,14S,17S)-13,17-diethyl-17-hydroxy-1,2,6,7,8,14,15,16-octahydrocyclopenta[a]phenanthren-3-one
InChI codeInChI=1S/C21H28O2/c1-3-20-11-9-17-16-8-6-15(22)13-14(16)5-7-18(17)19(20)10-12-21(20,23)4-2/h9,11,13,18-19,23H,3-8,10,12H2,1-2H3/t18-,19+,20+,21+/m1/s1

Other names (synonyms)

IUPAC nomenclature provides a standardized method for naming chemical compounds. Although this system is widely used in chemistry, many chemical compounds have also other names commonly used in different contexts. These synonyms can come from a variety of sources and are used for a variety of purposes.

One common source of synonyms for chemical compounds is the common or trivial names, assigned on the basis of appearance, properties, or origin of the molecule.

Another source of synonyms are historical or obsolete names employed in the past, however replaced nowadays by more modern or standardized names.

In addition to common and historical names, chemical compounds may also have synonyms that are specific to a particular field or industry.

  • (10S,11S,14S,15S)-14,15-diethyl-14-hydroxytetracyclo[^{2,7}.0^{11,15}]heptadeca-1,6,16-trien-5-one
  • (17.ALPHA.)-13-ETHYL-17-HYDROXY-18,19-DINORPREGNA-4,9,11-TRIEN-3-ONE
  • (17a)-13-ethyl-17-hydroxy-18,19-Dinorpregna-4,9,11-trien-3-one
  • (8S,13S,14S,17S)-13,17-diethyl-17-hydroxy-1,2,6,7,8,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-3-one (non-preferred name)
  • (8S,13S,14S,17S)-13,17-diethyl-17-hydroxy-1,2,6,7,8,14,15,16-octahydrocyclopenta[a]phenanthren-3-one
  • 18,19-DINORPREGNA-4,9,11-TRIEN-3-ONE, 13-ETHYL-17-HYDROXY-, (17.ALPHA.)-
  • 618903-56-3
  • 643MR6L9LB
  • BIDD:ER0580
  • Clear
  • DB06870
  • FT-0675003
  • Q416940
  • Tetrahydrogestrinone
  • Tetrahydrogestrinone (THG)

Reference codes for other databases

There exist several different chemical codes commonly used in orded to identify molecules:
  • ZINC12496366
  • UNII-643MR6L9LB
  • AKOS030242734
  • DTXSID60210901
  • CHEBI:190313
  • SCHEMBL4434724

Physico-Chemical properties

IUPAC name(8S,13S,14S,17S)-13,17-diethyl-17-hydroxy-1,2,6,7,8,14,15,16-octahydrocyclopenta[a]phenanthren-3-one
Molecular formulaC21H28O2
Molecular weight312.446
Melting point (ºC)
Boiling point (ºC)
Density (g/cm3)
Molar refractivity94.32
Topological polar surface area37.3

LogP and topological polar surface area (TPSA) values were estimated using Open Babel software.

The n-octanol/water partition coeficient (Kow) data is applied in toxicology and drug research. Kow values are used, to guess the environmental fate of persistent organic pollutants. High partition coefficients values, tend to accumulate in the fatty tissue of organisms. Molecules with a log(Kow) (or LogP) greater than 5 are considered to bioaccumulate.

TPSA values are the sum of the surface area over all polar atoms or molecules, mainly oxygen and nitrogen, also including hydrogen atoms.

In medicinal chemistry, TPSA is used to assess the ability of a drug to permeabilise cells.

For molecules to penetrate the blood-brain barrier (and act on receptors in the central nervous system), TPSA values below 90 Å2 are required. Thus, molecules with a polar surface area greater than 140 Å2 tend to be poorly permeable to cell membranes.