Pinealon

1 Identity

Short-chain bioregulator (Khavinson peptide family). Synthetic linear tripeptide, all three residues L and proteinogenic, free N-terminal alpha-amino group and free C-terminal carboxylic acid, no acylation, no amidation, no cyclization, no disulfide, no metal. Two dicarboxylic side chains (Glu, Asp) and one strongly basic guanidino side chain (Arg) make it markedly hygroscopic and give it a low isoelectric point — a handling fact, and one that governs both the storage condition and the chromatography. There is no aromatic residue and therefore no chromophore stronger than the amide bond. Not A synonym and not this article: Endoluten, the pineal peptide-extract preparation from the same product family, which is a compositionally undefined organ extract on a different panel and is never sourced against this purchase specification.

Sequence

H-L-Glu-L-Asp-L-Arg-OH (EDR). Free N-terminal alpha-amino group, free C-terminal carboxylic acid, no acetylation, no amidation, no cyclization, no disulfide; all three residues L and proteinogenic. Supplied as the acetate salt; trifluoroacetate lots are refused. The sequence remains a supplier claim until MS/MS confirms the residue order on the first lot from every supplier and after any change of manufacturing site — and on a three-residue peptide that is not a formality, because all six permutations of Glu, Asp and Arg share one formula and one exact mass, and so does the beta-aspartyl rearrangement product at the internal Asp.

Molecular formula

C15H26N6O8 as the free peptide. Supplied as the acetate salt, which is not a fixed stoichiometry and is therefore specified as a percentage range rather than as a formula; the shipped mass is peptide plus acetate plus water, and at 6.0-16.0 percent acetate this article carries the highest counterion fraction of any peptide in this catalog, so no single formula describes the vial.

Average mass

418.407 Da (C15H26N6O8), from the formula on IUPAC 2021 abridged conventional atomic weights (C 12.011, H 1.008, N 14.007, O 15.999) and independently reconstructed residue by residue from EDR; the two routes agree to the digit. A figure of 418.402 also circulates for this article, and the difference is worth knowing: 418.402 is the same formula on the pre-2021 atomic-weight table (C 12.0107, H 1.00794, N 14.0067, O 15.9994), which returns 418.4023 exactly. Neither figure is wrong; this catalog standardizes on the IUPAC 2021 abridged table and states the basis on the face of every mass, so 418.407 is the printed figure. Sellers and suppliers print 418.4 or 418.407 and are consistent with either table within rounding.

Monoisotopic mass

418.18121 Da neutral; [M+H]+ 419.18849; [M+2H]2+ m/z 210.09788; [M-H]- 418.17393. Identity window on [M+H]+ at plus or minus 5 ppm is plus or minus 0.0021 Da. These figures do not move between atomic-weight tables — monoisotopic masses are built from nuclide masses — so 418.18121 and 419.18849 stand whichever table produced the average alongside them.

Salt / variant note

A three-residue peptide is the hardest article in this catalog to identify by mass, because the mass carries almost no information. START with what mass cannot see at all: every permutation of Glu, Asp and Arg — EDR, DER, RED, ERD, DRE, RDE — has the identical formula C15H26N6O8 and the identical 418.18121 monoisotopic mass, and so does the beta-aspartyl (iso-Asp) rearrangement product at the internal Asp. Six sequence isomers plus one rearrangement product, one mass; MS/MS or co-elution against a qualified standard is the only discriminator. The near-mass family, every figure on one calculator: Vesugen (KED) C15H26N4O8, 390.393 / 390.17506 — identical carbon and hydrogen counts, a formula differing only in nitrogen, 28.02 Da light. Epitalon (AEDG) C14H22N4O9, 390.349 / 390.13868 — indistinguishable from Vesugen at nominal mass 390 and separated from it by 0.0364 Da (93 ppm), so a certificate reading "MW 390" has identified neither, and either one substituted here is 28 Da from where it should be. Cardiogen (AEDR) C18H31N7O9, 489.486 / 489.21833 — the same three residues with an alanine on the front, exactly 71.08 Da heavy, and the most plausible same-family mis-ship. Pancragen (KEDW) C26H36N6O9, 576.607. Testagen (KEDG) C17H29N5O9, 447.445. Livagen (KEDA) C18H31N5O9, 461.472. Vilon (KE) C11H21N3O5, 275.305. Chonluten (EDG) C11H17N3O8, 319.270. Terminus and dehydration variants: the C-terminal amide EDR-NH2, C15H27N7O7, 417.423 / 417.19720, exactly 0.984 Da light; and the cyclized or anhydro species at minus 18.011 Da, 400.39. Salt axis: acetate as specified at 6.0-16.0 percent w/w — the highest counterion fraction of any article in this catalog — against trifluoroacetate, which is refused. Second article under A neighboring name: Endoluten, the pineal peptide-extract preparation from the same product family, is a compositionally undefined organ extract, a different article on a different panel, and is not sourced against this purchase specification.

2 Class & testing panel

Form

Single article

Testing panel

P1 — panel definition

3 Primary sources & evidence

The index reports the design and provenance of the literature, not a conclusion about effect.

Published literature exists and it is single-center. It is predominantly Russian-language, from one St Petersburg institute and its collaborators, and comprises in-vitro work in neuronal and other cell cultures, rodent studies, and a set of English-language reviews by the same authors restating the same primary work. Independent replication outside that group has not been identified. No controlled human trial of this tripeptide is registered on ClinicalTrials.gov, no Western regulatory agency has reviewed it, and there is no public pharmacokinetic or formal toxicology package. A class-level listing places the family under an "FDA category 2" group heading; that is a heading applied to the group entry, not a substance-specific FDA determination for this molecule, and the distinction is preserved here. The literature is genuinely narrow and the catalog page presents it as narrow, with literature volume by study type printed at the head of the research page rather than a citation count.

4 Storage & specification

Storage

White to off-white lyophilized powder, acetate salt, in clear or amber glass vials with a nitrogen headspace and desiccant. Labeled condition -20 degrees C plus or minus 5 degrees C, desiccated. Moisture, not light, is the controlling degradation risk on this article — there is no chromophore and no photolabile center, but two dicarboxylic side chains and a guanidino group make it strongly hygroscopic — so the vial is equilibrated to room temperature sealed before opening and is closed under nitrogen after each withdrawal, and both are specification items rather than packaging preferences. A single excursion to 2-8 degrees C of up to 30 days cumulative is permitted and recorded on the lot record. Shipped on gel packs with a temperature logger filed against the shipment. Non-sterile, no sterility claim, no stoppered-and-crimped injection format, no dose-shaped vial.

Shelf life

Provisional 24-month retest interval at -20 degrees C plus or minus 5 degrees C. Provisional, and replaced by this company's own three-lot ICH Q1A-format study — long-term at -20 degrees C, accelerated at 25 degrees C / 60 percent RH, with A dedicated open-dish moisture-uptake arm because hygroscopicity is the identified risk on this molecule — at the 12-month data point. The stability-indicating attributes are the pyroglutamate-cyclized and aspartimide-related species and Karl Fischer water trended together, not total assay: water gain alone will move an assay result without any chemical change at all, which is the specific failure mode this article invites. Until then the interval is a stated engineering assumption and the catalog labels it as one. It is shortened on data and never extended without a completed dataset.