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

What is the Protirelin?

The molecule Protirelin presents a molecular formula of C16H22N6O4 and its IUPAC name is (2S)-N-[(2S)-1-[(2S)-2-carbamoylpyrrolidin-1-yl]-3-(1H-imidazol-5-yl)-1-oxopropan-2-yl]-5-oxopyrrolidine-2-carboxamide.

Protirelin is a synthetic molecule that is structurally similar to the hormone thyrotropin-releasing hormone (TRH). It is used as a diagnostic tool in the evaluation of the hypothalamic-pituitary-thyroid (HPT) axis and as a research tool to study the role of TRH in various physiological processes. Protirelin has been shown to stimulate the release of thyroid-stimulating hormone (TSH) from the pituitary gland in humans and animals. This effect is thought to be mediated by the activation of TRH receptors in the pituitary. Protirelin has also been shown to stimulate the release of prolactin from the pituitary in humans. The exact mechanism by which protirelin stimulates prolactin release is not known, but it is thought to involve the activation of TRH receptors in the pituitary..

3D structure

Cartesian coordinates

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

2D drawing


Protirelin XNSAINXGIQZQOO-SRVKXCTJSA-N chemical compound 2D structure molecule svg


Molecule descriptors

IUPAC name(2S)-N-[(2S)-1-[(2S)-2-carbamoylpyrrolidin-1-yl]-3-(1H-imidazol-5-yl)-1-oxopropan-2-yl]-5-oxopyrrolidine-2-carboxamide
InChI codeInChI=1S/C16H22N6O4/c17-14(24)12-2-1-5-22(12)16(26)11(6-9-7-18-8-19-9)21-15(25)10-3-4-13(23)20-10/h7-8,10-12H,1-6H2,(H2,17,24)(H,18,19)(H,20,23)(H,21,25)/t10-,11-,12-/m0/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.

  • (2S)-N-[(1S)-2-[(2S)-2-carbamoylpyrrolidino]-1-(1H-imidazol-5-ylmethyl)-2-keto-ethyl]-5-keto-pyrrolidine-2-carboxamide
  • (2S)-N-[(2S)-1-[(2S)-2-aminocarbonylpyrrolidin-1-yl]-3-(1H-imidazol-5-yl)-1-oxidanylidene-propan-2-yl]-5-oxidanylidene-pyrrolidine-2-carboxamide
  • (2S)-N-[(2S)-1-[(2S)-2-carbamoylpyrrolidin-1-yl]-3-(1H-imidazol-4-yl)-1-oxopropan-2-yl]-5-oxopyrrolidine-2-carboxamide
  • (2S)-N-[(2S)-1-[(2S)-2-carbamoylpyrrolidin-1-yl]-3-(1H-imidazol-5-yl)-1-oxopropan-2-yl]-5-oxopyrrolidine-2-carboxamide
  • (2S)-N-[(2S)-1-[(2S)-2-carbamoylpyrrolidin-1-yl]-3-(3H-imidazol-4-yl)-1-oxopropan-2-yl]-5-oxopyrrolidine-2-carboxamide
  • (Pyro)-L-glutamic acid-L-histidine-L-proline-NH2
  • (S)-N-((S)-1-((S)-2-carbamoylpyrrolidin-1-yl)-3-(1H-imidazol-4-yl)-1-oxopropan-2-yl)-5-oxopyrrolidine-2-carboxamide
  • (S)-N-((S)-1-((S)-2-carbamoylpyrrolidin-1-yl)-3-(1H-imidazol-5-yl)-1-oxopropan-2-yl)-5-oxopyrrolidine-2-carboxamide
  • 1-(3-(1H-Imidazol-5-yl)-2-([(5-oxo-2-pyrrolidinyl)carbonyl]amino)propanoyl)-2-pyrrolidinecarboxamide #
  • 1-[3-(1H-4-imidazolyl)-2-(5-oxotetrahydro-1H-2-pyrrolylcarboxamido)propanoyl]tetrahydro-1H-2-pyrrolecarboxamide
  • 11096-37-0
  • 117217-40-0
  • 2-Pyrrolidinecarboxamide, N-[1-[(2-Carbamoyl-1-pyrrolidinyl)carbonyl]-2-imidazol-4-ylethyl]-5-oxo-, (S,S,S)-
  • 2-Pyrrolidinecarboxamide, N-[1-[(2-carbamoyl-1-pyrrolidinyl)carbonyl]-2-imidazol-4-ylethyl]-5-oxo-,
  • 24305-27-9
  • 24305-27-9 (free base)
  • 305T279
  • 5-Oxo-L-prolyl-L-histidyl-L-prolinamide
  • 5-oxo-pro-his-pro-nh2
  • 5Y5F15120W
  • A-38579
  • A858244
  • ABBOTT-38579
  • Abbott 38579
  • BCP12450
  • BDBM50072394
  • C03958
  • C74244
  • CCG-268193
  • CCRIS 2593
  • D00176
  • DB09421
  • DSSTox_CID_3533
  • DSSTox_GSID_23533
  • DSSTox_RID_77067
  • FDA 1725
  • GTPL2139
  • GTPL3836
  • HS-2023
  • HY-P0002
  • Human Transferrin
  • L-Prolinamide, 5-oxo-L-prolyl-L-histidyl-
  • L-Pyroglutamyl-L-histidinyl-L-prolinamide
  • L-Pyroglutamyl-L-histidyl-L-prolinamide
  • L-Pyroglutamyl-L-histidyl-L-proline amide
  • L-Pyroglutamyl-L-histidyl-L-prolineamide
  • Lopremone
  • MFCD00038640
  • NCGC00160616-01
  • NSC 760113
  • NSC-760113
  • PR 546
  • PR-546
  • Prolinamide, 1-[N-(5-oxo-L-prolyl)-L-histidyl]-, L-
  • Prolinamide, 5-oxo-L-prolyl-L-histidyl-, L-
  • Protirelin
  • Protirelin (JP17/USAN/INN)
  • Protirelin tartrate
  • Protirelin, synthetic
  • Protirelina
  • Protireline
  • Protirelinum
  • PyroGlu-His-prolinamide
  • Q24726011
  • Relefact TRH
  • Relefact-TRH
  • Rifathyroin
  • Ro 8-6270/9
  • Siderophilin;partially saturated
  • Stimu-TSH
  • Synthetic TRF
  • Synthetic TRH
  • Synthetic thyrotopin releasing factor
  • Synthetic thyrotropin-releasing factor
  • Synthetic thyrotropin-releasing hormone
  • Synthetic tsh-releasing factor
  • Synthetic tsh-releasing hormone
  • TRF
  • TRH
  • TSH-RF
  • TSH-releasing factor
  • TSH-releasing hormone
  • Thypinone
  • Thyrefact
  • Thyroid releasing hormone
  • Thyroid-stimulating hormone-releasing factor
  • Thyroliberin
  • Thyroliberin;Lopremone;Synthetic TRH;Thyrotropin-releasing hormone; Rifathyroin
  • Thyrothropin relasing hormone
  • Thyrotrophic hormone releasing hormone
  • Thyrotrophin releasing hormone
  • Thyrotropic hormone-releasing factor
  • Thyrotropic hormone-releasing hormone
  • Thyrotropic releasing hormone
  • Thyrotropic-releasing factor
  • Thyrotropin releasing hormone
  • Thyrotropin releasing hormone, powder, gamma-irradiated, cell culture tested
  • Thyrotropin-ReleasingHormone
  • Thyrotropin-releasing factor
  • Thyrotropin-releasing factor (pig)
  • Thyrotropin-releasing hormone
  • [3H]-TRH
  • [3H]-thyrotropin-releasing hormone
  • [3H]TRH (human, mouse, rat)
  • pGlu-His-Pro-NH2
  • protirelin
  • pyroglutamyl-histidyl-prolinamide
  • s4680
  • trh-sr

Reference codes for other databases

There exist several different chemical codes commonly used in orded to identify molecules:
  • ZINC4096261
  • CAS-24305-27-9
  • UNII-5Y5F15120W
  • AKOS015994636
  • DTXSID0023533
  • CHEMBL1472
  • CHEBI:35940
  • Tox21_111939
  • EINECS 246-143-4
  • SCHEMBL33419
  • SCHEMBL19825647

Physico-Chemical properties

IUPAC name(2S)-N-[(2S)-1-[(2S)-2-carbamoylpyrrolidin-1-yl]-3-(1H-imidazol-5-yl)-1-oxopropan-2-yl]-5-oxopyrrolidine-2-carboxamide
Molecular formulaC16H22N6O4
Molecular weight362.384
Melting point (ºC)
Boiling point (ºC)
Density (g/cm3)
Molar refractivity96.85
Topological polar surface area150.3

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.