Vesilut

1 Identity

Base synthetic dipeptide. Two proteinogenic L-residues, free alpha-amino N-terminus, free C-terminal carboxyl, no acylation, no amidation, no cyclization, no cysteine, no disulfide, no metal, no non-proteinogenic residue. It is the smallest peptide held here and the most acidic: three carboxyl groups — the Glu1 side chain, the Asp2 side chain and the C-terminal acid — against a single amino group, so the molecule carries a net negative charge at any working pH and is very poorly retained on conventional reversed phase. No aromatic residue, therefore no 280 nm chromophore. Supplied as the lyophilized free acid or as an alkali-metal or acetate salt; a trifluoroacetate counterion is chemically possible but commercially uncommon on a di-acid. A trade name within the Khavinson "cytogen" line of defined synthetic short peptides, as distinct from the "cytomax" tissue-extract line sold from the same shelf, which is a different kind of article and not a synonym for this one.

Sequence

H-L-Glu-L-Asp-OH (ED). Two residues, both L, joined through the glutamate alpha-carboxyl. Free N-terminus, free C-terminal acid, no end-caps, no modifications, no disulfide. Three attributes fix this identity and not one of them is A mass: the residue order (Glu-Asp, not Asp-Glu), the glutamyl linkage (alpha, not gamma), and the configuration (both L). Recorded caution, carried on the face of this record as it is on the other trade-named short peptides in this catalog: "Vesilut" is a trade name, and the Glu-Asp assignment is an originator and vendor attribution rather than a structure tied to a public reference standard or a pharmacopeial monograph. It is treated as unconfirmed until MS/MS with a fully assigned b/y series on a qualified lot confirms it against a named standard.

Molecular formula

C9H14N2O7 (free acid). Salt forms carried as separate formula units: mono-acetate C11H18N2O9; disodium C9H12N2Na2O7; mono-trifluoroacetate C11H15F3N2O9. The formula is shared exactly by the reversed dipeptide H-Asp-Glu-OH, by the gamma-linked isomer and by every stereoisomer, which is precisely why it is not an identity statement on its own.

Average mass

262.218 Da (C9H14N2O7, free acid), computed on IUPAC 2021 abridged conventional atomic weights and independently reconstructed residue-by-residue from Glu plus Asp plus water; the two routes agree to the digit. The figure is corroborated externally through the exact isomer rather than through the article itself: a reagent supplier's catalog entry for H-Asp-Glu-OH publishes C9H14N2O7 and MW 262.22. Salt forms: mono-acetate 322.270; disodium 306.182; mono-trifluoroacetate 376.240 — and on a 262 Da peptide a single trifluoroacetate counterion is 43% of the article's own mass, the highest counterion burden anywhere in this catalog.

Monoisotopic mass

262.08010 Da neutral (C9H14N2O7). Working ions: [M-H]- m/z 261.07282, [M+H]+ m/z 262.08738, [M+Na]+ m/z 285.06932. Negative mode is the correct choice and is written into the method: three carboxylates and one amine make this a poor positive-mode ion and a good negative one. A plus or minus 5 ppm window on the neutral is plus or minus 0.0013 Da. That window is trivially met and excludes almost nothing, because the molecules that matter here share the formula exactly.

Salt / variant note

The principal risk on this molecule is that its exact isomer is A catalog reagent sold by A major institutional supplier while the article itself is not. H-Asp-Glu-OH, CAS 6157-06-8, C9H14N2O7, MW 262.22, stocked at 250 mg: identical formula, identical average mass, identical monoisotopic mass at 262.08010, identical to every decimal place at every resolving power, and a different molecule. Accurate mass at any accuracy separates them not at all; only an assigned b/y ion series, Edman after the appropriate treatment, or co-elution against two named standards can. That is not a hypothetical substitution — it is the only version of this composition that a buyer can actually purchase from a reagent house. Further exact isomers, all C9H14N2O7 at 262.08010: gamma-linked Glu-Asp, the regiochemical by-product of coupling through the glutamate side chain; beta-linked Asp-containing isomers; and the D-containing stereoisomers at either center. Mass-resolvable neighbors: Glu-Asn and Gln-Asp C9H15N3O6, 261.234 / 261.09609, minus 0.98 Da, the amide forms and the direct precursors of a deamidation impurity read backwards; Asp-Asp C8H12N2O7, 248.191 / 248.06445, minus 14.03 Da; Glu-Glu C10H16N2O7, 276.245 / 276.09575, plus 14.03 Da and a stocked catalog reagent in its own right; pyroGlu-Asp C9H12N2O6, 244.203 / 244.06954, minus 18.011 Da, the cyclization product of the N-terminal glutamate and the named degradant for this sequence; free L-Glu 147.130 / 147.05316 and free L-Asp 133.103 / 133.03751, the unreacted starting materials. Same-family articles sold from the same page at the same size, each with its own derived mass: Vilon KE C11H21N3O5 275.305 / 275.14812; Chonluten EDG C11H17N3O8 319.270 / 319.10156; Cartalax AED C12H19N3O8 333.297 / 333.11721; Ovagen EDL C15H25N3O8 375.378 / 375.16416; Pinealon EDR C15H26N6O8 418.407 / 418.18121; Vesugen KED C15H26N4O8 390.393 / 390.17506; Epitalon AEDG C14H22N4O9 390.349 / 390.13868. And the sideways risk into the extract line: the Cytomax organ preparations are sold under the same brand lineage by the same sellers and have no mass at all.

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.

Literature exists at the level of the program rather than of this molecule, and is recorded by study type with no statement of effect. The Khavinson short-peptide class carries an evidence grade of D — animal and in-vitro work plus non-independent, largely Russian-language reviews from the originating institution, with no independently replicated randomized human trial located. Class citations carried: Khavinson VKh, Neuro Endocrinol Lett 2002, PMID 12374906, review; Khavinson V, Linkova N, Diatlova A, Trofimova S, Stem Cell Rev Rep 2020, PMID 31808038, DOI 10.1007/s12015-019-09938-8, review and the source of the program's verbatim structural claim; Khavinson VK and Kvetnoii IM, Bull Exp Biol Med 2000, PMID 11276315, rat study; Khavinson VKh, Kuznik BI and Ryzhak GA, Adv Gerontol 2012, PMID 23734519 and Adv Gerontol 2013, PMID 24003726, both reviews by the originating group rather than primary randomized trials; Mironova ES et al., Adv Gerontol 2020, PMID 32593244, review; Avolio F et al., Int J Mol Sci 2022, PMID 35408963, DOI 10.3390/ijms23073607, in-vitro human cell line, internationally co-authored. No publication specific to Vesilut under its own name was located in a search of 14 August 2026, and it is not among the members named in any of the primary studies above. No ClinicalTrials.gov registration was identified and no NCT number is quoted because none was found. No marketing authorization in any jurisdiction. The research page carries the field's objection to the program's central structural claim: a dipeptide has too few contacts to specify a unique genomic site, and no independent replication was located.

4 Storage & specification

Storage

Lyophilized white to off-white powder in the sealed original container with in-pack desiccant, protected from light. Labeled storage minus 20 degrees C plus or minus 5 degrees C, desiccated; 2 to 8 degrees C is acceptable for transit and for working stock held no longer than 30 days, and the in-use stability study brackets that condition. The material is strongly hygroscopic, which on a 262 Da article is a specification matter and not a handling nicety: condensation onto a cold cake moves the water figure enough to move the net peptide claim, and the net peptide claim is the label. Vials are equilibrated to room temperature sealed before opening. Reconstituted aqueous solutions are refrigerated and used promptly; a free-termini dipeptide is substrate for any residual amino- or carboxypeptidase activity in a biological matrix, which is an experimental-design consideration for the buyer and is stated as such. Shipping validation covers a 72-hour excursion to 25 degrees C.

Shelf life

Provisional 36 months at minus 20 degrees C plus or minus 5 degrees C in the sealed original container, assigned by protocol and not measured, pending this company's own long-term and accelerated data on the first three lots to ICH Q1A format. The interval is longer than the 24-month house default for the same reason it is longer on Vesugen: an unmodified, disulfide-free, methionine-free, tryptophan-free, aromatic-free dipeptide is among the most chemically stable articles in the catalog. The three attributes to trend are not gross purity: N-terminal pyroglutamate formation at minus 18.011 Da, the aspartate succinimide and iso-aspartate pair, and water content. The stability-indicating method must be demonstrated to resolve the pyroglutamyl species from parent before the first lot is placed on stability. The interval is shortened on data and never extended without a completed dataset.