Compound monograph
Macimorelin
Macimorelin is a gem-diamino peptidomimetic agonist at the ghrelin receptor.
01
Identity & nomenclature
Macimorelin is a gem-diamino peptidomimetic agonist at the ghrelin receptor.
Macimorelin is neither a ghrelin fragment nor an ordinary unmodified tripeptide; the peptidomimetic connectivity is what defines it. Acetate in a salt preparation must not become a covalent N-acetyl modification in the structural record.
Declared aliases and development codes: AEZS-130, JMV 1843, EP-1572.
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Molecular properties
| Molecular formula | C26H30N6O3 |
|---|---|
| Molecular mass | 474.56 Da |
| CAS Registry Number | 381231-18-1 |
| PubChem CID | 9804938 |
| UNII | 8680B21W73 |
| Terminal groups | N-formyl gem-diamino terminus |
No conventional amino-acid sequence string exists for this molecule and none is published here. It is a gem-diamino peptidomimetic: an Aib-derived unit and a D-Trp-derived unit connected to an R-configured, indole-containing gem-diamino terminus bearing an N-formyl group. A terminal 'CHO' abbreviation is a formamide arrangement, not a free peptide aldehyde.
03
Structural characteristics
A cryo-EM structure of the ghrelin receptor bound to macimorelin, determined alongside an anamorelin-bound structure, shows both occupying a bifurcated pocket divided by a conserved salt bridge, with mutagenesis identifying the residues behind their differing affinities. That permits a direct structural comparison rather than an assumption that all ghrelin mimetics bind alike. An assay-independent signalling-bias designation is not established.
- gem-diamino linkage
- D-tryptophan-derived unit
Terminal features: N-formyl gem-diamino terminus.
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Molecular targets & mechanisms
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Analytical considerations
An amino-acid composition result or a peptide search-engine match is insufficient for this terminus. NMR is needed to establish gem-diamino connectivity and N-formyl placement, with a chiral method for the defined stereocentres. Counterion content for acetate material is a separate measurement; the parent ion establishes neither acetate stoichiometry nor peptide-equivalent content.
Disagreements and mix-ups
Points where sources disagree about this compound's identity, or where a name or form is easily confused with another, as noted in this record. The discrepancy register quotes the passage for each one.
Often mixed up · Salt or form
Acetate salt vs a covalent N-acetyl groupAlso noted in N-Acetyl Semax Amidate, N-Acetyl Selank Amidate
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
Gq-coupled GHSR cryo-electron microscopy preparation
Using a Gq-coupled GHSR cryo-electron microscopy preparation, the study reported the macimorelin-bound structure at 2.63 Å resolution.
Reference [2]Macimorelin-bound Gq-coupled GHSR structural preparation
Using a macimorelin-bound Gq-coupled GHSR structural preparation, the study identified a bifurcated ligand-binding pocket divided by the conserved E1243.33-R2836.55 salt bridge.
Reference [2]Human pituitary GHS receptor and hGHS-R 1a binding assays
Using human pituitary GHS receptor and hGHS-R 1a binding assays, the study reported high potency for compound 7, JMV 1843.
Reference [1]
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Verified bibliography
Cited studies by type
The 3 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
New active series of growth hormone secretagogues.Guerlavais V, Boeglin D, Mousseaux D, Oiry C, Heitz A, Deghenghi R, Locatelli V, Torsello A, Ghé C, Catapano F, Muccioli G, Galleyrand JC, Fehrentz JA, Martinez J
Journal of medicinal chemistry · 2003-03-27 · Journal Article
currentReference 2
Molecular recognition of two approved drugs Macimorelin and Anamorelin by the growth hormone secretagogue receptor.Wang RL, Sun J, Liu H, Guo SM, Zhang Y, Hu W, Wang J, Liu H, Zhuang YW, Jiang Y, Xie X, Xu HE, Wang Y
Acta pharmacologica Sinica · 2025-06-20 · Journal Article
currentReference 3
Molecular recognition of an acyl-peptide hormone and activation of ghrelin receptor.Wang Y, Guo S, Zhuang Y, Yun Y, Xu P, He X, Guo J, Yin W, Xu HE, Xie X, Jiang Y
Nature communications · 2021-08-20 · 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 |
|---|---|
| Guerlavais V et al. 2003 | Study models reported: in vitro; animal (rat, beagle dog) · from the abstract |
| Wang RL et al. 2025 | Study models reported: in vitro · from the abstract |
| Wang Y et al. 2021 | Study models reported: in vitro · from the abstract |
Record history
Published 2026-09-13.
- : Identity and nomenclature
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. Macimorelin. Published 2026-09-13; updated 2026-10-16. https://purelypeptides.org/research/compounds/macimorelin/
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Methodology & citation verification
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