Compound monograph
Leuprolide (leuprorelin)
Leuprorelin, also called leuprolide, is a synthetic nine-residue peptide with an L-pyroglutamyl residue at position 1, D-leucine at position 6 and an N-ethylamide on the C-terminal proline. This record describes the parent peptide without counterion or hydrate.
01
Identity & nomenclature
Leuprorelin, also called leuprolide, is a synthetic nine-residue peptide with an L-pyroglutamyl residue at position 1, D-leucine at position 6 and an N-ethylamide on the C-terminal proline. This record describes the parent peptide without counterion or hydrate.
Leuprorelin is the WHO international nonproprietary name (Latin leuprorelinum) and leuprolide the United States adopted name; both denote this parent peptide. Salt-qualified names such as leuprolide acetate describe the peptide together with a counterion and are not aliases of this record: the Japanese Pharmacopoeia specifies a monoacetate, while an FDA chemistry review describes one or two acetate equivalents. Development codes and trade names are not listed because no two independent sources tie them to this exact species.
Canonical name: Leuprorelin.
Declared aliases and development codes: Leuprolide, Leuprorelinum.
02
Molecular properties
| Molecular formula | C59H84N16O12 |
|---|---|
| Molecular mass | 1209.421 Da |
| CAS Registry Number | 53714-56-0 |
| PubChem CID | 657181 |
| UNII | EFY6W0M8TG |
| Three-letter sequence | pGlu–His–Trp–Ser–Tyr–D-Leu–Leu–Arg–Pro |
| Terminal groups | N-terminal pyroglutamate; C-terminal N-ethylamide at Pro9 |
Nine residues numbered pGlu1 to Pro9. pGlu is L-pyroglutamyl (5-oxo-L-prolyl), a residue whose side chain is cyclized onto its own amino group; it is not open-chain glutamate or glutamine. Position 6 is D-leucine and every other chiral residue is L. The C-terminal N-ethylamide is a terminal group, not a tenth residue. No one-letter string is published because the chain contains a nonstandard residue and a D residue.
03
Structural characteristics
The WHO proposed-INN entry and the Japanese Pharmacopoeia monograph give the full structure with explicit configuration at every residue. Laimou et al. (PMID 20354741) studied leuprolide in solution by two-dimensional NMR, and Sanz-Nebot et al. (PMID 10722088) characterized crude synthesis products by liquid chromatography-mass spectrometry. Nederpelt et al. (PMID 26398856) measured leuprolide binding at the human GnRH receptor; Morgan et al. (PMID 24490142) measured it at the rat GnRH receptor expressed in cultured cells. The pyroglutamyl ring lies within residue 1; there is no ring closure between residues.
- Pyroglutamate at position 1
- D-leucine at position 6
Terminal features: N-terminal pyroglutamate, C-terminal N-ethylamide at Pro9.
04
Molecular targets & mechanisms
05
Analytical considerations
The molecular formula and the 1209.421 Da average mass are calculated for the neutral parent from its structure with CIAAW 2024 abridged atomic weights; the Japanese Pharmacopoeia lists 1209.40 using an earlier atomic-weight table. D-leucine and L-leucine at position 6 have the same composition, so an intact-mass match does not confirm the configuration. One acetate equivalent adds C2H4O2, about 60.05 Da, so salt preparations do not share the parent's mass.
What the studies reported
Each finding describes one cited study in its stated model. These observations are specific to that study and do not establish effects in other settings.
Cell and tissue studies
Leuprolide in DMSO-d6 and D2O NMR assays
Laimou et al. observed NMR evidence for a type-I beta turn in leuprolide residues 2-5 in DMSO-d6 and a type-II beta turn in residues 3-6 in D2O.
Reference [1]Tumorigenic HEK293[SCL60] and WPE-1-NB26-3 prostate cells expressing rat GnRH receptors
Morgan et al. observed agonist and antiproliferative activity for D-Leu6 GnRH analogues, including leuprolide, in tumorigenic HEK293[SCL60] and WPE-1-NB26-3 prostate cells expressing rat GnRH receptors.
Reference [4]
06
Verified bibliography
Cited studies by type
The 4 papers this record cites, counted by the kind of work each reports. A count is the size of this record's selection, not of the research that exists, and says nothing about results, safety, effectiveness or approval.
A paper can report more than one kind of work. Each count opens those papers in the bibliography. Compare every record on the Evidence Map.
Reference 1
Structural elucidation of Leuprolide and its analogues in solution: insight into their bioactive conformation.Laimou DK, Katsara M, Matsoukas MT, Apostolopoulos V, Troganis AN, Tselios TV
Amino acids · 2010-03-31 · Journal Article
currentReference 2
Separation and characterization of multicomponent peptide mixtures by liquid chromatography-electrospray ionization mass spectrometry. Application to crude products of the synthesis of leuprolide.Sanz-Nebot V, Benavente F, Barbosa J
Journal of chromatography. A · 2000-02-18 · Journal Article
currentReference 3
Characterization of 12 GnRH peptide agonists - a kinetic perspective.Nederpelt I, Georgi V, Schiele F, Nowak-Reppel K, Fernández-Montalván AE, IJzerman AP, Heitman LH
British journal of pharmacology · 2015-11-04 · Journal Article
currentReference 4
Probing the GnRH receptor agonist binding site identifies methylated triptorelin as a new anti-proliferative agent.Morgan K, Leighton SP, Millar RP
Journal of molecular biochemistry · 2012-06-16 · Journal Article
current
Study models of these references
What kind of experiment each cited paper reports, taken from its abstract unless marked. Not a summary of results.
| Reference | Study models |
|---|---|
| Laimou DK et al. 2010 | Study models reported: in vitro · from the abstract |
| Sanz-Nebot V et al. 2000 | Chemical, structural or analytical study; no biological model reported |
| Nederpelt I et al. 2015 | Study models reported: in vitro · from the abstract |
| Morgan K et al. 2012 | Study models reported: in vitro · from the abstract |
Record history
Published 2026-10-15.
No changes to this record's content have been recorded since publication.
Each entry names the parts of this record that changed on that date. Changes to links between records and to catalogue links are not listed. This history covers the tracked record fields; study findings are not listed here.
Cite this record: Purely Peptides Research Library. Leuprolide (leuprorelin). Published 2026-10-15. https://purelypeptides.org/research/compounds/leuprolide/
10
Methodology & citation verification
Reference identity is checked against official PubMed metadata. Local deterministic receipts bind each normalized title and canonical metadata record to its verification date. Scientific values remain absent when an authoritative source has not been verified.
Read the full methodology →