Normophthal

1 Identity

Short-chain bioregulator of the Khavinson series — composition undeclared. The series' published members are di-, tri- and tetrapeptides of proteinogenic L-amino acids, unmodified at both termini in most cases, supplied as lyophilized acetate or trifluoroacetate salts; whether the article sold under this name is one of them is exactly what is not established. A trade name within the Khavinson short-peptide series, not a chemical name. The only commercial attribution located resolves the name onto a different marketed product: one seller prints "normophthal" as an alternative name on its Vilon listing, i.e. The lysine-glutamic acid dipeptide. That attribution is recorded as an observation about that seller's listing and is not adopted as an identity.

Sequence

No defined sequence, and this record does not state one. No primary source states the amino-acid sequence of the material sold under this designation. The characterization of it as a two-residue dipeptide is carried as an unconfirmed attribution and nothing more. What can be said of the series and no more: its published members are di-, tri- and tetrapeptides of proteinogenic L-amino acids, unmodified at both termini in most cases. A further trap sits inside even the dipeptide reading: for a two-residue peptide the residue order is a separate molecule from the same formula, so Lys-Glu and Glu-Lys are both C11H21N3O5 at 275.1481 monoisotopic and are distinguishable only by MS/MS fragment ordering or by co-elution against a characterized standard.

Molecular formula

Not established. No molecular formula can be written for an article whose sequence is undeclared, and none is asserted here.

Average mass

Not established — confirm against a reference standard before listing. There is no theoretical mass to check a certificate against because there is no confirmed molecular formula. The figure is obtained only when the manufacturer's head of quality states the complete sequence, the terminal chemistry and the counterion in writing on the approved API specification, and it is then confirmed independently by amino-acid molar-ratio analysis and accurate mass against a characterized reference standard before it is entered here.

Monoisotopic mass

Not established, for the same reason. No monoisotopic mass is printed. When one is entered it will be reported to four decimal places, because the near neighbors in this series are separated by hundredths of a dalton — see the salt and variant note below, where Epitalon and Vesugen differ by 0.0364 Da monoisotopic and are wholly indistinguishable at any lower precision.

Salt / variant note

The usual confusable risk inverts for this article: the risk is not that a named analog is substituted for a known compound, it is that any Khavinson-series peptide can be shipped under this trade name and no arithmetic exists to contradict it. What a buyer can do is identify which known series member they were actually sent. Vilon, Lys-Glu (KE), C11H21N3O5, avg 275.305 / mono 275.1481, [M+H]+ 276.1554 — the attribution actually in commercial use for this name. Thymogen, Glu-Trp (EW), C16H19N3O5, avg 333.344 / mono 333.1325, [M+H]+ 334.1397. Epitalon, Ala-Glu-Asp-Gly (AEDG), C14H22N4O9, avg 390.349 / mono 390.1387, [M+H]+ 391.1460. Vesugen, Lys-Glu-Asp (KED), C15H26N4O8, avg 390.393 / mono 390.1751, [M+H]+ 391.1824. Note the pair: Epitalon and Vesugen differ by 0.044 Da on average mass and by 0.0364 Da monoisotopic, so nominal-mass data separates them not at all, and even a 5 ppm measurement must be reported to four decimals to do so. Ovagen, Glu-Asp-Leu (EDL), C15H25N3O8, avg 375.378 / mono 375.1642. Livagen, Lys-Glu-Asp-Ala (KEDA), C18H31N5O9, avg 461.472 / mono 461.2122. A further axis ignored by every storefront: for a dipeptide the residue order is a separate molecule from the same formula — Lys-Glu and Glu-Lys are both C11H21N3O5 at 275.1481 — so even the dipeptide reading of this name leaves two candidate molecules standing.

2 Class & testing panel

Form

Single article

Testing panel

P1 — panel definitionprovisionally, contingent on the sequence. The provisional assignment holds only if the declared sequence proves to be short, all-L and proteinogenic. If it contains a D-residue or any non-proteinogenic residue the panel becomes P3 and a chiral method becomes mandatory rather than a first-lot qualification test; if the article turns out to be the excipient-filled retail capsule rather than a synthetic peptide, the panel becomes P7. The panel cannot be finalized before the sequence is

3 Primary sources & evidence

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

Published literature exists at series level only. The Khavinson short-peptide literature is dominated by one research group, is largely Russian-language, and consists mainly of in-vitro and rodent work with limited independent replication and few pre-registered protocols. For this trade name specifically, no primary publication was identified that states the compound's sequence, which means there is no product-specific evidence base to describe: the honest position is that the company does not know what has been studied, because it does not know what the compound is. No controlled human trial meeting United States registrational standards was identified for this designation, and no ClinicalTrials.gov registration under it was found. This record reflects that state exactly — it says the sequence is unresolved and links nothing it cannot attribute.

4 Storage & specification

Storage

White lyophilized powder, stored at -20 degrees C plus or minus 5 degrees C in the sealed original container with desiccant, protected from light, equilibrated to room temperature before opening. Short polar peptide salts of this type are strongly hygroscopic and the desiccant is a control with an acceptance check, not a courtesy. Shipped frozen with a validated shipper and a temperature logger. The condition is provisional in one further respect: if the confirmed sequence contains an oxidation-labile or photolabile residue, the storage statement is rewritten to match it.

Shelf life

Provisional 24-month retest interval at -20 degrees C plus or minus 5 degrees C, and it cannot be finalized, because the degradation pathway that will govern it depends on a sequence the company does not yet have. A short peptide with an N-terminal glutamate will be dated on pyroglutamate formation; one carrying tryptophan or methionine will be dated on oxidation; one carrying an Asp-Gly junction will be dated on aspartimide; one carrying none of these will be dated on water uptake. The stability protocol is written the day the sequence is confirmed and not before, and the interval published on the first certificate is whatever three lots of real-time data at -20 degrees C support.