Compound monograph

Thymosin alpha-1

Thymalfasin, also called thymosin alpha-1, is a linear 28-residue peptide. Its primary structural candidate corresponds to the N-terminal region of prothymosin alpha after the initiator methionine.

Published: 2026-09-28Last updated: 2026-10-13Literature/identifier verification: 2026-09-28

Also known asThymosin alpha1Thymosin α1

Identity & nomenclature

Thymalfasin, also called thymosin alpha-1, is a linear 28-residue peptide. Its primary structural candidate corresponds to the N-terminal region of prothymosin alpha after the initiator methionine.

Thymalfasin is the recommended international nonproprietary name; thymosin alpha-1 is the common scientific display name. The shared historical thymosin designation does not establish a common structural family with beta-thymosins. PubChem CID 16130571 and GSRS UNII W0B22ISQ1C, which lists CAS 62304-98-7, describe the conventional N-acetylated 28-mer with a free C-terminal acid; these candidates do not resolve this record’s held complete-sequence assignment.

Canonical name: Thymalfasin.

Declared aliases and development codes: Thymosin alpha1, Thymosin α1.

Molecular properties

Terminal groups	N-terminal acetylation at Ser1; Free C-terminal carboxyl

The primary structural candidate corresponds to residues 2-29 of reviewed human prothymosin alpha, using precursor numbering that includes the initiator methionine. Mature-peptide numbering starts at Ser1. The complete sequence is withheld because collected source renderings remain conflicted.

Structural characteristics

The defined candidate has an acetylated N-terminus and a free C-terminal carboxyl group. It is linear, with standard L-amino-acid residues and no cysteine or disulfide. The complete sequence, molecular formula and average molecular mass remain conflicted and are withheld.

Terminal features: N-terminal acetylation at Ser1, Free C-terminal carboxyl.

Molecular targets & mechanisms

Analytical considerations

The acetyl cap is not an additional amino-acid residue. Average molecular mass, neutral monoisotopic mass and an ion mass are different quantities; agreement of a calculated candidate with one reported value does not resolve the held identity fields.

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.

Sources disagree · unresolved · Sequence
Complete sequence, formula and mass across sources
Often mixed up · Name or substance
Thymosin alpha-1 vs the beta-thymosins

What the studies reported

No verified findings are published for this record under Content Policy v1.

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.

Chemical, structural or analytical; no biological model1

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
NMR structure of human thymosin alpha-1.
Elizondo-Riojas MA, Chamow SM, Tuthill CW, Gorenstein DG, Volk DE
Biochemical and biophysical research communications · 2011-11-15 · Journal Article
current
PMID 22115779 PMC3419376 DOI 10.1016/j.bbrc.2011.11.041 Thymosin alpha-1

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
Elizondo-Riojas MA et al. 2011	Chemical, structural or analytical study; no biological model reported

Record history

Published 2026-09-28.

2026-10-13: 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. Thymosin alpha-1. Published 2026-09-28; updated 2026-10-13. https://purelypeptides.org/research/compounds/thymosin-alpha-1/

Methodology & citation verification

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