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Background And Chemical Identity — Field Notes

By Editorial Desk · published 2026-08-01 · last reviewed 2026-08-01 · Wiki

epithalamin raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.

This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.

Background and Chemical Identity

Several names circulate for the same molecule, including epitalon, epithalone, epithalamin tetrapeptide, and the sequence code AEDG. A CAS registry number, 307297-39-8, is commonly cited for it, though catalogue entries should be checked against supplier documentation because mislabelled records occur. In its usual form the peptide carries free amino and carboxyl termini and is neither glycosylated nor lipidated. Researchers distinguish the defined tetrapeptide from epithalamin itself, a crude pineal preparation containing many peptides that is not chemically characterised.

Material supplied for laboratory use is normally a lyophilised white to off-white powder that dissolves readily in water and in isotonic saline. Lyophilised cakes are hygroscopic and should be equilibrated to room temperature before opening to limit condensation on the solid. Solutions are typically prepared at milligram-per-millilitre concentrations and divided into single-use aliquots, because repeated freeze–thaw cycles degrade short peptides. Aqueous solutions are far less stable than the dry powder, and identity is usually verified by mass spectrometry alongside purity estimation from reversed-phase high-performance liquid chromatography.

Structure, Naming and Discovery

Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.

Epitalon is a synthetic tetrapeptide whose four residues are alanine, glutamate, aspartate and glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9 and its monoisotopic mass is near 390.35 daltons. The peptide carries two acidic side chains, so it is neutral to negatively charged in most aqueous buffers. Published reference summaries usually list it under both spellings, epitalon and epithalon, and treat the two names as the same material.

The compound is generally described as a synthetic analogue of a fragment isolated from a pineal gland extract. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology introduced it during the 1980s and 1990s while studying short peptides from animal tissue. The original extract, called epithalamin, is a heterogeneous mixture, whereas epitalon is a single defined sequence. That distinction matters because findings reported for the extract are not automatically findings about the pure tetrapeptide, and claims about broader biological effects remain a separate question from the chemical identity described here.

Epitalon at a glance

PropertyValueNotes
Amino acid sequenceAla-Glu-Asp-GlyLinear tetrapeptide, also written AEDG
Molecular massAbout 390.35 g/molValue calculated from the sequence
AppearanceWhite to off-white powderLyophilised material forms a loose cake
SolubilityFreely soluble in waterAlso dissolves in isotonic saline
Storage-20 °C, desiccatedAliquot solutions to avoid freeze–thaw cycling

Reference notes

IndieDB () is an offshoot of ModDB launched in June 2010. It is dedicated to indie gaming and serves as a repository for those games. Like ModDB, the website hosts an annual competition for the best indie game of the year, with the games being voted on in categories and overall. Also like ModDB, the nominees are selected by the site's editors and voted on by its readers. Winners of the Indie of the Year Awards include Minecraft by Mojang in 2010, RimWorld by Ludeon Studios in 2016 and Ion Fury by Voidpoint in 2019.

=== Non-peptides === CA7 – among smallest-known oxytocin receptor agonists; considerable selectivity over the vasopressin V1A receptor KNX-200 (KNX200) – series; chemical structure(s) not yet disclosed LIT-001 — improved social deficits in mice; non-selective over vasopressin receptors LIT-002 – highly potent, under formal development TC OT 39 – non-selective over vasopressin receptors WAY-267,464 – anxiolytic in mice; possibly non-selective over vasopressin receptors WJ0679 – among smallest-known oxytocin receptor agonists; produces prosocial effects in rodents In April 2025, a series of novel and highly potent small-molecule oxytocin receptor agonists with high selectivity over the vasopressin V1A receptor (up to >5,000-fold) were patented and described.

leading strand In DNA replication, the nascent strand for which both the direction of synthesis by DNA polymerase and the direction of overall chain elongation are toward the replication fork; i.e. both occur in the 5' to 3' direction, resulting in a single, continuous elongation process with few or no interruptions. By contrast, the other nascent strand, known as the lagging strand, is assembled in a discontinuous process involving the ligation of short DNA fragments synthesized in the opposite direction, away from the replication fork.

=== Breakthrough in talks === On the evening of 8 October 1972, at a secret meeting of Kissinger and Tho in a house in the Paris suburb of Gif-sur-Yvette once owned by the painter Fernand Léger, the decisive breakthrough in the talks came. Tho believed that Kissinger was, as he later put it, "in a rush" for a peace deal before the presidential election, and began with what he called "a very realistic and very simple proposal" for a ceasefire that would see the Americans pull all their forces out of Vietnam in exchange for the release of all the POWs in North Vietnam. As for the ultimate fate of South Vietnam, Tho proposed the creation of a "council of national reconciliation" that would govern the nation, but in the meantime, Thiệu could stay in power until the council was formed, while a "leopard's spot" ceasefire would come into effect with the Viet Cong and the Saigon government controlling whatever territories they were had at the time of the ceasefire. The "mutual withdrawal formula" was to be disregarded, with PAVN forces to stay in South Vietnam, with Tho giving Kissinger a vague promise that no more supplies would be sent down the Ho Chi Minh Trail. Kissinger accepted Tho's offer as the best deal possible, saying that the "mutual withdrawal formula" had to be abandoned, as it had been "unobtainable through ten years of war...We could not make it a condition for a final settlement. We had long passed that threshold".

The tests can be performed manually when automated equipment is not available or when the analyzer results indicate that further investigation is needed. Automated results are flagged for manual blood smear review in 10–25% of cases, which may be due to abnormal cell populations that the analyzer cannot properly count, internal flags generated by the analyzer that suggest the results could be inaccurate, or numerical results that fall outside set thresholds. To investigate these issues, blood is spread on a microscope slide, stained with a Romanowsky stain, and examined under a microscope. The appearance of the red and white blood cells and platelets is assessed, and qualitative abnormalities are reported if present. Changes in the appearance of red blood cells can have considerable diagnostic significance—for example, the presence of sickle cells is indicative of sickle cell disease, and a high number of fragmented red blood cells (schistocytes) requires urgent investigation as it can suggest a microangiopathic hemolytic anemia. In some inflammatory conditions and in paraprotein disorders like multiple myeloma, high levels of protein in the blood may cause red blood cells to appear stacked together on the smear, which is termed rouleaux. Some parasitic diseases, such as malaria and babesiosis, can be detected by finding the causative organisms on the blood smear, and the platelet count can be estimated from the blood smear, which is useful if the automated platelet count is inaccurate.

Sources: en.wikipedia.org

Related pages on this site

Notes from published material

== Contraindications == Benzodiazepines require special precaution if used in the elderly, during pregnancy, in children, alcohol or drug-dependent individuals and individuals with comorbid psychiatric disorders. Phenazepam should not be taken with alcohol or any other CNS depressants. Phenazepam should not be used therapeutically for periods of longer than one month including tapering on and off the drug as recommended for any benzodiazepine in the British national formulary. Some patients may require longer term treatment. Phenazepam was found to be a component in some "herbal incense" mixtures in Australia and New Zealand in 2011, namely "Kronic". The particular product variety was withdrawn from the market shortly after and replaced with a new formulation.

=== Psychosis === Selegiline has been studied as an adjunct to antipsychotics in the treatment of schizophrenia in four clinical studies. However, it failed to significantly reduce positive or negative symptoms of schizophrenia in meta-analyses of these studies.

A photosensitizer is a chemical compound or nanomaterial capable of capturing light energy and using this energy to generate ROS. Currently, there are 6 photosensitizers that are clinically-approved or undergoing clinical trials for the treatment of cancers and 1 approved for the treatment of eye disorders and diseases. Photodynamic therapy (PDT) is also often used for acne treatment as well as various dermatological conditions such as psoriasis, atopic dermatitis, and vitiligo. It is highly unlikely that bacteria would gain resistance to a photosensitizer or PDT treatment, as the photosensitizers can generate ROS within or outside of the target cell, both of which damage the membrane

Sometimes distinct from the modern periods themselves, the terms "modernity" and "modernism" refer to a new way of thinking, distinct from previous ways of thinking such as medieval thinking. "Postmodernism", coined in 1949, describes a movement in art rather than a period of history, and is usually applied to arts, but not to any events of recent history. This changed, when postmodernity was coined to describe major changes in the 1960s in economy, society, culture, and philosophy. These terms stem from European history. In worldwide usage, such as in China, India, and Islam, the terms are applied in a different way, but often in the context with their contact with European culture in the Age of Discovery.

Sources: en.wikipedia.org

Background from the literature

The 3D structure of human serum albumin has been determined by X-ray crystallography to a resolution of 2.5 ångströms (250 pm). Albumin is a 65–70kDa protein. Albumin comprises three homologous domains that assemble to form a heart-shaped protein. Each domain is a product of two subdomains that possess common structural motifs. The principal regions of ligand binding to human serum albumin are located in hydrophobic cavities in subdomains IIA and IIIA, which exhibit similar chemistry. Structurally, the serum albumins are similar, each domain containing five or six internal disulfide bonds. Worldwide, certain traditional Chinese medicines contain wild bear bile, banned under CITES legislation. Dip sticks, similar to common pregnancy tests, have been developed to detect the presence of bear albumin in traditional medicine products, indicating that bear bile had been used in their creation. Albumin is pronounced ; formed from Latin: albumen "egg white", itself derived from the Latin albus: white.

Liquid metal molybdenum-containing targets have been proposed that would aid in streamlined processing, ensuring better production yields. A particular problem associated with the continued reuse of recycled, enriched 100Mo targets is unavoidable transmutation of the target as other Mo isotopes are generated during irradiation and cannot be easily removed post-processing.

1921 Research on the role of pancreas in the nutritive assimilation 1922 Frederick Banting, Charles Best and James Collip use bovine insulin extract in humans at Connaught Laboratories in Toronto, Canada. 1922 Leonard Thompson becomes the first human to be treated with insulin. 1922 James D. Havens, son of former congressman James S. Havens, becomes the first American to be treated with insulin. 1922 Elizabeth Hughes Gossett, daughter of the US Secretary of State, becomes the first American to be (officially) treated in Toronto. 1923 Dr. Trent Champion de Crespigny delivers the first treatments with insulin produced in Australia, to a 9-year-old, in Adelaide, South Australia, on 7 January 1923. 1923 Eli Lilly produces commercial quantities of much purer bovine insulin than Banting et al. had used 1923 Farbwerke Hoechst, one of the forerunners of today's Sanofi Aventis, produces commercial quantities of bovine insulin in Germany 1923 Hans Christian Hagedorn founds the Nordisk Insulinlaboratorium in Denmark – forerunner of today's Novo Nordisk 1923 Constance Collier returns to health after being successfully treated with insulin in Strasbourg 1924 Margaret Cheadle, a research biochemist in the laboratory of T. Brailsford Robertson at the University of Adelaide, determined that approx. 167 "mouse units" of insulin were "equivalent to one two-kilogram rabbit-unit". 1926 Nordisk receives a Danish charter to produce insulin as a non-profit 1936 Canadians David M. Scott and Albert M.

Sources: en.wikipedia.org

Frequently asked questions

Is epitalon a natural substance?

It is a synthetic tetrapeptide. Its sequence was derived from research on peptide fractions of bovine pineal extract, and the intact AEDG sequence has not been demonstrated as an abundant free peptide in human tissue.

What does the abbreviation AEDG mean?

AEDG is the one-letter code for the four amino acids alanine, glutamate, aspartate and glycine in that order. The same molecule is written in three-letter form as Ala-Glu-Asp-Gly.

How is the identity of epitalon confirmed in a laboratory?

Identity is normally confirmed by mass spectrometry against the calculated mass of roughly 390.35 g/mol. Purity is then estimated by reversed-phase high-performance liquid chromatography with ultraviolet detection.

What is epitalon made of?

It is a four-amino-acid peptide built from alanine, glutamate, aspartate and glycine in that order. Its formula is C14H22N4O9, and it is made by chemical synthesis rather than extracted from tissue. The synthetic peptide is a single defined molecule, unlike the pineal extracts it is often compared with.

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