Compound monograph
N-Acetyl Semax Amidate
N-Acetyl Semax Amidate is the Semax heptapeptide with an acetyl group on the N-terminal methionine residue and an amide at the C-terminal proline. These covalent terminal changes define a distinct molecule.
01
Identity & nomenclature
N-Acetyl Semax Amidate is the Semax heptapeptide with an acetyl group on the N-terminal methionine residue and an amide at the C-terminal proline. These covalent terminal changes define a distinct molecule.
The complete name specifies both terminal groups. A bare N-acetyl Semax label does not specify the C-terminal group and is not an alias here. Acetate salt terminology does not establish covalent N-acetylation. PubChem CID 172638603 represents the recorded amidate structure. No CAS or UNII is assigned here because no authoritative assignment was verified. PubChem CID 172638603 includes CAS 2920938-90-3 among deposited synonyms, but that association has not independently established the CAS assignment for the N-acetylated, C-amidated species.
02
Molecular properties
| Molecular formula | C39H54N10O10S |
|---|---|
| Molecular mass | 855 Da |
| PubChem CID | 172638603 |
| One-letter sequence | MEHFPGP |
| Three-letter sequence | Met–Glu–His–Phe–Pro–Gly–Pro |
| Terminal groups | N-terminal acetylation at Met1; C-terminal amide at Pro7 |
The seven residue positions are unchanged from Semax. In shorthand, Ac and NH2 denote the N-terminal acetyl and C-terminal amide groups; they are not additional residues.
03
Structural characteristics
The residue sequence preserves the ACTH(4-7)-plus-Pro-Gly-Pro construction of Semax. N-terminal acetylation adds C2H2O to the free-terminal parent; C-terminal amidation adds H and N and removes O. Together the changes add C2H3N and yield C39H54N10O10S. The direct parent link identifies this structural relationship.
Terminal features: N-terminal acetylation at Met1, C-terminal amide at Pro7.
04
Molecular targets & mechanisms
05
Analytical considerations
Table 1 of Vanhee et al. (PMID 31667971) corroborates the C39H54N10O10S formula for a custom-synthesized reference standard from Thermo Fisher Scientific. The sequence column describes the ordered standard, not a sequence established for a seized amidate sample. This citation supplies formula corroboration only for this record; the Selank-specific rLys-C discrimination does not apply here. Table 1 reports 854.3745 Da monoisotopic mass. The library records 855.0 Da average mass, derived from the formula using its conventional atomic weights. The paper is not the original source of the name-to-sequence mapping.
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 Macimorelin, N-Acetyl Selank Amidate
Often mixed up · Name or substance
"N-acetyl Semax" without the amidate
What the studies reported
No verified findings are published for this record under Content Policy v1.
06
Verified bibliography
Cited studies by type
The one paper 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
The occurrence of putative cognitive enhancing research peptides in seized pharmaceutical preparations: An incentive for controlling agencies to prepare for future encounters of the kind.Vanhee C, Francotte A, Janvier S, Deconinck E
Drug testing and analysis · 2020-01-29 · 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 |
|---|---|
| Vanhee C et al. 2020 | Chemical, structural or analytical study; no biological model reported |
Compare
Record history
Published 2026-09-28.
- : Sequence and structure
- : 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. N-Acetyl Semax Amidate. Published 2026-09-28; updated 2026-10-15. https://purelypeptides.org/research/compounds/n-acetyl-semax-amidate/
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 →