Epithalon: Chemistry Profile & Research Overview

What Is Epithalon?

Epithalon is a synthetic tetrapeptide assigned CAS number 307297-39-8, with the four-residue sequence Ala-Glu-Asp-Gly (single-letter: AEDG). It is a synthetic analog of epithalamin, a peptide fraction originally isolated from the pineal gland in research animals. Among the synthetic regulatory peptides characterized in the chemical literature, Epithalon is one of the shortest — consisting of only four amino acid residues with a molecular weight under 400 g/mol. As a research-grade synthetic peptide, Epithalon is used in vitro and in non-human systems as a model substrate in telomerase-activity assay methodology, in solid-phase peptide synthesis (SPPS) studies, and as a reference compound in short-peptide pharmacology research.

Chemical Properties

Historical Development and Discovery

The Epithalon sequence was developed in the early 1990s by Vladimir Khavinson and colleagues at the St. Petersburg Institute of Bioregulation and Gerontology as part of a long-running structure-activity research program on short pineal-derived peptides. The work began with characterization of epithalamin, a partially purified peptide fraction isolated from the pineal gland of research animals, and progressed through systematic sequence simplification to identify the minimal active fragment. The four-residue Ala-Glu-Asp-Gly sequence emerged as the shortest tetrapeptide retaining the in vitro binding profile of the parent fraction. The compound entered the chemical literature as Epithalon (also spelled Epitalon) and has since become a reference standard in short-peptide methodology research and in the broader study of the Russian-developed regulatory peptide line that also includes Selank and Semax.

Chemical Architecture and Structural Features

Minimal Tetrapeptide Design

The defining structural feature of Epithalon is its compactness: at only four residues and 390 Da, it sits at the lower end of the size range for synthetic regulatory peptides. The sequence Ala-Glu-Asp-Gly carries two acidic side chains (Glu and Asp) which contribute the bulk of its hydrogen-bonding and ionic interaction profile in research matrices. The N-terminal alanine and C-terminal glycine residues provide minimal steric bulk, leaving the two acidic residues exposed for binding interactions.

Comparison with the Russian Regulatory Peptide Line

Epithalon is part of a broader family of short Russian-developed peptides that includes Selank (heptapeptide with Pro-Gly-Pro extension) and Semax (heptapeptide ACTH(4-7) analog with Pro-Gly-Pro extension). Unlike those compounds, Epithalon does not carry a proline-rich stabilization motif — its short length and high content of acidic residues distinguish its biochemical profile. Comparative research on these peptides is a recognized area of short-peptide chemistry.

Solid-Phase Synthesis Considerations

Epithalon is produced by Fmoc-based solid-phase peptide synthesis (SPPS) followed by RP-HPLC purification. The four-residue length and absence of cysteine, methionine, or tryptophan residues make the synthesis straightforward. The principal challenge in the literature is aspartimide formation at the Asp-Gly junction, which is addressed through pseudoproline protection or by using 2-hydroxy-4-methoxybenzyl side-chain protecting groups on the aspartate residue.

Research Mechanisms

In published in vitro and non-human research, Epithalon has been characterized as a short bioactive tetrapeptide derived from the pineal regulatory peptide fraction. The compound has been used as a model substrate in telomerase-activity assay methodology, in receptor-binding methodology research, and in peptide-stability comparison studies against the broader Russian regulatory peptide line. ITide Labs supplies Epithalon as a research-grade reference standard for these applications.

Research Areas

• Telomerase-activity assay methodology research
• Solid-phase peptide synthesis of short acidic-residue peptides
• Aspartimide-suppression methodology research
• Comparative structure-activity research on Russian regulatory peptides
• Reference standard in analytical method development (HPLC-UV, LC-MS)
• Short-peptide pharmacology and binding methodology

Quality Assurance

ITide Labs releases each lot of Epithalon against an independent third-party Certificate of Analysis. Lot-specific COAs are published on the corresponding product page once analysis is complete. Identity is confirmed by LC-MS, purity by RP-HPLC-UV, and endotoxin levels by kinetic chromogenic LAL assay. Lyophilized material is stored at 2–8 °C protected from light and is supplied with batch-specific documentation.

Frequently Asked Questions

What is the CAS number for Epithalon?

The CAS number for Epithalon is 307297-39-8.

What is the molecular weight of Epithalon?

The molecular weight of Epithalon is 390.35 g/mol. The empirical formula is C₁₄H₂₂N₄O₉.

What is the amino acid sequence of Epithalon?

The single-letter sequence of Epithalon is AEDG — a 4-residue tetrapeptide composed of Alanine, Glutamic acid, Aspartic acid, and Glycine.

Is Epithalon the same as Epitalon?

Yes. Epithalon and Epitalon are alternate spellings of the same compound (CAS 307297-39-8). Both refer to the synthetic tetrapeptide Ala-Glu-Asp-Gly.

How does Epithalon relate to epithalamin?

Epithalon is a synthetic four-residue analog derived from systematic structure-activity research on epithalamin, a peptide fraction originally isolated from the pineal gland in research animals. Epithalon represents the minimal active sequence identified through that research program.

Why is Epithalon used in research?

Epithalon is used as a reference standard in telomerase-activity assay methodology, in short-peptide pharmacology research, in aspartimide-suppression SPPS research, and in comparative studies of the Russian regulatory peptide line.

Is Epithalon a peptide or a small molecule?

Epithalon is a peptide — a 4-residue synthetic tetrapeptide. At 390 g/mol it sits near the boundary between conventional peptides and small molecules, but it is biosynthetically a peptide.

What laboratory storage does Epithalon require?

Lyophilized Epithalon should be stored at 2–8 °C protected from light for short-term storage and at –20 °C for long-term storage. Reconstituted solutions should be aliquoted and stored frozen.

Who developed Epithalon?

Epithalon was developed in the early 1990s by Vladimir Khavinson and colleagues at the St. Petersburg Institute of Bioregulation and Gerontology, as part of structure-activity research on short pineal-derived peptides.

Is Epithalon available in different sizes from ITide Labs?

ITide Labs currently supplies Epithalon as a 50 mg lyophilized lot. Lot-specific Certificates of Analysis are published on the product page once independent third-party characterization is complete.

Citation

ITide Labs. Epithalon: Chemistry Profile and Research Overview. Las Vegas, NV: ITide Labs LLC; 2026.