Noopept (Omberacetam) Reference Standard — CAS 157115-85-0, ≥99% by HPLC

1. Substance identity and registry data

Noopept is the common name for ethyl 2-[[(2S)-1-(2-phenylacetyl)pyrrolidine-2-carbonyl]amino]acetate, better described in peptide terms as N-phenylacetyl-L-prolylglycine ethyl ester [1]. Its international nonproprietary name is omberacetam.

That name is misleading in the same way the whole racetam label is misleading here. Noopept is not a 2-oxopyrrolidine acetamide; it is a dipeptide ethyl ester built from proline and glycine with a phenylacetyl cap. It shares no functional group arrangement with piracetam. What it shares is a design intent: it was conceived as a peptide mimic of the piracetam pharmacophore, which is a different claim entirely and is discussed in section 11.

Every identifier below comes from a public authoritative registry [1][2].

Noopept, omberacetam or GVS-111 — what is the difference?

None at the level of the substance: all three name CAS 157115-85-0. GVS-111 is the development code used throughout the primary Russian literature [12][13][14][16]; searching on it finds work that the other two names miss. Omberacetam is the INN. Noopept is the name under which the substance reached the consumer market and the one most likely to appear on a sample submitted for analysis.

Three identifiers that do not exist for this substance are worth naming: there is no ChEBI entry, no KEGG identifier and no ATC code [1]. The absent ATC code is the meaningful one — it confirms that omberacetam has never been an authorised medicine in any system that assigns them.

2. Molecular structure

The molecule has three regions, and unusually for this catalogue each one is a potential point of chemical change rather than merely a property.

The phenylacetyl cap supplies the only ultraviolet chromophore — a plain monosubstituted benzene ring. It absorbs weakly and without structure, which is why ultraviolet detection for this compound is workable but unimpressive, and why mass spectrometry earns its place.

The L-proline ring carries the single stereocentre and, more importantly, the secondary amide nitrogen that makes the proline–glycine bond geometrically special. Proline amides are the classic site of cis/trans isomerism in peptides and the classic site of intramolecular cyclisation. Section 9 explains why that matters for storage.

The glycine ethyl ester is the terminus and the most labile part of the molecule: an ester on a small peptide, hydrolysable in principle and cyclisable in practice.

Structural neighbours in this catalogue

The instructive comparison is with the compounds noopept is shelved beside rather than with anything it resembles. Oxiracetam and aniracetam are genuine 2-oxopyrrolidine acetamides; coluracetam carries that motif on a large heteroaromatic core. Noopept carries none of it. Grouping the four under one catalogue heading is a convention of the consumer market, not a statement of chemistry, and a chromatographic method built for one of them will not transfer to noopept.

3. Computed descriptors and what they predict

What these numbers predict in the laboratory

A computed logP of 1.5 with a polar surface area of 75.7 Ų describes a moderately polar, well-behaved reversed-phase analyte. Expect useful retention on C18 with a mid-range organic mobile phase — comfortably between the strongly retained bromantane standard and the barely retained polar racetams.

Seven rotatable bonds is the number to notice, and it is high. Compare 2 for bromantane and 3 for coluracetam. A flexible molecule can give broader peaks, more temperature-dependent retention and, in the case of a proline amide specifically, the possibility of cis/trans rotamers interconverting on the chromatographic timescale. If a peak for this compound looks broader or more shouldered than expected, rotameric exchange is a candidate explanation before column degradation is assumed — and raising the column temperature is the diagnostic experiment, since it speeds the exchange and sharpens the peak.

One donor and four acceptors, no ionisable centre of consequence. Neither amide is acidic in a usable range and the ester is neutral, so mobile-phase pH is a weak lever on retention. Stationary-phase chemistry does the work of adjusting selectivity.

A weak chromophore. The single unconjugated phenyl ring absorbs around 254 nm without a distinctive maximum. Ultraviolet detection works for assay at reasonable concentrations but is poor for identity confirmation; mass spectrometry is the appropriate technique where identity is in question.

4. Stereochemistry: the L-proline centre

Noopept has one defined stereocentre and no undefined ones [1]. It sits at the α-carbon of the proline residue and it is defined because the molecule is built from L-proline, a chiral pool starting material.

The registry record marks this explicitly. The InChI carries the stereochemical layer /t14-/m0/s1, and the standard InChIKey ends in -AWEZNQCLSA-N. That second block is the one to read: it is not UHFFFAOYSA, the marker for a structure with no stereochemical information. For this substance the difference between those two strings is the difference between a defined single enantiomer and an unspecified one.

5. Solid-state behaviour and solution preparation

Unlike most substances in this catalogue, noopept has real, recent, measured solid-state data — and it comes from a Polish group. Araj, Szeleszczuk and colleagues at the Medical University of Warsaw, working with collaborators in Athens and Łódź, published a physicochemical and structural analysis of the compound in the Journal of Pharmaceutical and Biomedical Analysis in 2025 [7]. The study combined single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry, solid-state ¹³C cross-polarisation magic-angle-spinning NMR, and periodic density-functional calculations, and it included a polymorph screen.

What remains absent is the ordinary catalogue physics: the compound registry still lists no melting point, no solubility and no measured partition coefficient [1]. This page prints none of them.

Preparing stock solutions

The computed polarity places noopept comfortably in methanol, acetonitrile, ethanol and dimethyl sulfoxide. Aqueous working dilutions are feasible at analytical concentrations, which is not true of the lipophilic standards in this catalogue.

The caution specific to this molecule concerns aqueous and basic conditions. It is an ester on a dipeptide; both hydrolysis and intramolecular cyclisation are chemically available routes, and section 9 sets out why the second matters more than the first. Prepare aqueous dilutions fresh, keep them cold, avoid basic buffers for storage, and do not assume that a stock solution left overnight contains what it contained when it was made.

6. Use as an analytical reference standard

6.1 Why this substance needs one

Noopept is widely present in products sold as dietary supplements. The United States National Institutes of Health dietary supplement label database records dozens of labelled products containing it [6], and the Drug Enforcement Administration has carried it in the National Forensic Laboratory Information System reporting category since 2014 [5]. Cohen and colleagues, analysing cognitive-enhancement supplements sold in the United States, found unapproved drugs including omberacetam present in products and frequently at doses that did not match the label [10].

Laboratories screening such products need authenticated material for every substance they claim to identify. The coluracetam standard covers the same problem for a different compound in the same consumer category. For noopept the need is sharpened by the identity problem described next, which has no equivalent among the other standards in this catalogue.

6.2 The identity trap: the InChIKey prefix is not the substance

This is the strongest single technical reason to hold a characterised noopept standard, and it is a problem in the reference data itself rather than in any laboratory's method.

An InChIKey has two blocks. The first, fourteen characters, encodes the skeleton and connectivity. The second encodes stereochemistry, isotopes and protonation. Software and spreadsheets routinely match on the first block alone, because it is the part that looks like a fingerprint.

For noopept that shortcut fails. As recorded on 22 August 2026, three separate PubChem compound records share the prefix PJNSMUBMSNAEEN, and only one of them is this substance:

The gap is also visible in the literature: a PubMed search for work on the enantiomeric purity of noopept returns nothing, on an instrument that returned results for every other query in the same session. No published method distinguishes the L- and D-proline diastereomers of this compound.

6.3 The degradation trap: the degradant is the metabolite

The second distinctive property of this molecule is that its expected chemical breakdown product and its principal biological metabolite are the same compound.

Gudasheva and colleagues showed that the phenylacetyl-prolylglycine ethyl ester skeleton converts into cyclo-L-prolylglycine, the diketopiperazine formed by intramolecular cyclisation [11]. Independently, the same group had identified cyclo-L-prolylglycine as the major metabolite of GVS-111 in rat brain [12], having first characterised that cyclic dipeptide as an endogenous compound in its own right [13].

6.4 What Russian pharmaceutical analysis already established

Two papers deserve particular attention because they are the closest thing to an official analytical foundation for this substance. Gusev and colleagues published the development of analytical methods for the creation of a state reference sample of noopept [8], and Grushevskaya and colleagues published the pharmaceutical analysis and standardisation of noopept tablets [9]. Both appeared in Pharmaceutical Chemistry Journal.

These matter for two reasons. First, they are the only published work on this compound written from the perspective of a reference-standard producer rather than a pharmacologist. Second, their existence establishes that a formal reference sample of noopept was created within one regulatory system — which is a useful precedent, and also a reminder that the material supplied here is not that reference sample and does not carry its status (section 8).

7. Reference spectral data

8. Batch specification and Certificate of Analysis

The layout of the certificate and the method stated against each parameter can be reviewed on the specimen Certificate of Analysis.

9. Handling, storage and stability

• Storage. Sealed, cool, dry, protected from light.
• Cyclisation is the defining stability risk. The glycine ethyl ester and the proline amide are positioned for intramolecular attack, and the product is cyclo-L-prolylglycine [11][12]. Warmth, moisture and basic conditions all favour it. Do not store solutions at room temperature, do not use basic buffers for storage, and treat any new later- or earlier-eluting peak as a candidate diketopiperazine before calling it an unknown.
• Ester hydrolysis is the second available route and gives the corresponding free acid. It is favoured by the same conditions.
• Solid-state form. A published crystal structure and polymorph screen exist [7]. If solid-state form matters to the intended use, compare the batch against that work rather than assuming, and avoid recrystallising or drying by an undocumented route.
• Weighing. The compound registry gives no hygroscopicity data. Determine water content for the batch rather than assuming it is dry.
• Personal protection. Gloves, eye protection, containment of dust. See section 10 — the reason is the thinness of the classification, not its content.

10. Hazard classification

In practice: gloves, eye protection, containment of dust under local exhaust, no eating or drinking in the handling area, and a workplace risk assessment that records the thinness of the available data as a finding in its own right. The Safety Data Sheet shipped with the batch is the controlling document.

11. Discovery and development history

Noopept came out of the V. V. Zakusov Institute of Pharmacology in Moscow, from a research programme with an explicit design hypothesis: that the pharmacological activity of piracetam could be reproduced by a dipeptide that mimicked its presumed active conformation. The compound was developed under the code GVS-111 and first reported internationally in 1994 [16].

That design origin explains the structural mismatch discussed in section 1. Noopept was never intended to be a racetam by structure; it was intended to be a peptide that behaved like one. Whether the hypothesis was correct is a separate question, and the literature does not settle it.

The programme produced an unusually coherent body of work from one group. The endogenous cyclic dipeptide cyclo-prolylglycine was identified in rat brain in 1996 [13]; it was shown to be the principal brain metabolite of GVS-111 in 1997 [12]; the pharmacokinetics of the parent and its metabolites in rat brain were reported in 2001 [14]; a molecular mechanism was proposed in 2016 [15]; and in 2017 the same group reported that the parent converts into cyclo-L-prolylglycine and that the cyclic dipeptide shows a similar activity spectrum [11]. Read in order, those papers describe a compound whose active species may be its own metabolite.

In parallel, Russian pharmaceutical chemistry produced the analytical and standardisation work described in section 6.4 [8][9]. The substance reached the consumer market internationally under the name noopept, which is how it now arrives in analytical laboratories [6][10].

12. Preclinical pharmacology and metabolism

The mechanistic thread that matters analytically is metabolic rather than receptor-level. Boiko and colleagues reported the pharmacokinetics of GVS-111 and related metabolites in rat brain [14], and the identification of cyclo-L-prolylglycine as the major brain metabolite came from the same institute [12]. Vakhitova and colleagues later proposed a molecular mechanism for the substituted Pro-Gly dipeptide in Acta Naturae [15].

The 2017 finding that the parent ester converts into cyclo-L-prolylglycine, and that the cyclic dipeptide shows a comparable activity spectrum [11], is the pivot of the whole story: it raises the possibility that the administered compound functions largely as a precursor. For an analytical laboratory the reading is simpler and more useful — any method for this substance must be able to see both species and tell them apart.

13. Clinical research literature

The published analytical and standardisation work on noopept tablets [9] establishes that a tablet product existed and was subject to pharmaceutical standardisation within that system. This page does not assert anything about the current authorisation status of any such product, because that was not verified from a primary regulatory source for this revision.

What can be stated without qualification: omberacetam has no ATC code, no marketing authorisation in Poland or the European Union, and no entry in the Polish Register of Medicinal Products [1][4]. Section 14 gives the checks behind that.

14. Regulatory status

15. Permitted use and terms of supply

16. Frequently asked questions

What is noopept used for in a laboratory?

As an analytical reference standard, supplied with a batch Certificate of Analysis: to establish retention time and product-ion transitions in a laboratory's own method, to develop a stability-indicating method that separates the parent from its cyclisation product, to establish stereochemical purity, to spike blank matrix so that a real limit of detection can be measured, and to identify the substance in consumer products that declare or contain it. Because no published method distinguishes its stereoisomers, a laboratory doing that work is generating data that does not currently exist.

Is this product intended for human consumption?

No. It is a chemical reagent and analytical reference material supplied for in-vitro laboratory use only. It is not a medicinal product, supplement or food, it holds no marketing authorisation in Poland or the European Union, and it must not be ingested or administered to any human or animal.

What is the correct molecular formula and mass of noopept?

C17H22N2O4, average molecular mass 318.4 grams per mole, monoisotopic mass 318.15796 daltons. Listings quoting a formula containing sulfur, or a mass near 369, are wrong: this molecule contains no sulfur at all. The registry values are the ones above.

Is noopept the same thing as omberacetam or GVS-111?

Yes, all three name CAS 157115-85-0. Omberacetam is the international nonproprietary name, GVS-111 is the development code used throughout the primary Russian literature, and noopept is the name under which the substance reached the consumer market. Searching only on the marketing name will miss most of the scientific literature.

Is Nootropyl a synonym for noopept?

No, and the confusion is worth correcting explicitly. Nootropyl is a trade name of piracetam, CAS 7491-74-9, formula C6H10N2O2, molecular mass 142.16 grams per mole. It is a different molecule of less than half the mass. Similarly, the CAS number 304663-22-7 sometimes presented as a deprecated registry number for noopept belongs to a different compound; noopept has no deprecated CAS number.

Why can the InChIKey be misleading for this substance?

Because three separate PubChem records share its fourteen-character InChIKey prefix, and only one of them is noopept. One of the other two has no stereochemistry defined at all yet describes itself in its title as the S-isomer, and the third encodes the opposite configuration, built from D-proline, while describing itself as L-prolyl. Software that matches on the prefix alone will treat all three as identical, and reading the record titles instead does not help, because two of them contradict their own encoded structures. Identity for this compound resolves only on the full InChIKey, which for noopept is PJNSMUBMSNAEEN-AWEZNQCLSA-N.

Is noopept chiral?

Yes. It has one defined stereocentre, at the alpha carbon of the proline residue, because it is built from L-proline. The InChI carries a stereochemical layer and the InChIKey ends in AWEZNQCLSA rather than UHFFFAOYSA. This matters more than usual here: peptide chemistry can epimerise that centre, so the D-proline diastereomer is a real potential impurity and a stereochemical purity figure is meaningful for this material.

What degrades noopept, and how would I see it?

Intramolecular cyclisation to cyclo-L-prolylglycine, the diketopiperazine, is the chemically expected route, favoured by warmth, moisture and basic conditions. Ester hydrolysis to the free acid is the second route. The complication specific to this compound is that cyclo-L-prolylglycine is also its principal biological metabolite and is additionally an endogenous compound in its own right, so its presence in a chromatogram does not by itself distinguish degradation from metabolism or from natural occurrence. Resolving that requires the parent standard, a stability protocol and a matrix blank.

What is the melting point of noopept?

No melting point is published in the compound registry, and this page prints none. The same applies to solubility, density and measured partition coefficient. There is, however, a 2025 study reporting single-crystal and powder X-ray diffraction, thermal analysis and solid-state carbon-13 NMR for this compound, together with a polymorph screen, and that paper is the right starting point for any solid-state work.

What chromatographic conditions suit this compound?

Its computed logP of 1.5 and polar surface area of 75.7 square angstroms describe a moderately polar analyte that is comfortably retained on C18 with a mid-range organic mobile phase. There is no ionisable centre of consequence, so mobile-phase pH is a weak lever on retention. Note that the molecule has seven rotatable bonds and contains a proline amide, so if peaks appear broader or shouldered, rotameric exchange is a candidate explanation and raising the column temperature is the diagnostic experiment. The ultraviolet chromophore is a single unconjugated phenyl ring, so ultraviolet detection is adequate for assay but weak for identity; mass spectrometry is the better choice where identity is in question.

Is noopept banned in sport?

It is not listed by name on the World Anti-Doping Agency 2026 Prohibited List. That is not the same as being permitted. The List includes class S0, Non-Approved Substances, covering pharmacological substances not approved for human therapeutic use by any governmental regulatory health authority, and a substance with no marketing authorisation may fall within it regardless of whether it is named. Anyone competing under the World Anti-Doping Code should obtain a determination from their own anti-doping organisation rather than rely on a supplier page.

Is noopept legal in Poland?

It is not a controlled substance under the Polish list of narcotic drugs, psychotropic substances and new psychoactive substances, and it is not a registered medicine in Poland or the European Union. It is supplied here strictly as an analytical reference material under the terms in section 15. Not being on a controlled-substances list is not the same as being approved for any human use, and nothing on this page offers it for one.

What pack sizes are available?

Seven: 1 g, 5 g, 10 g, 20 g, 40 g, 80 g and 100 g, each supplied as crystalline powder with a batch Certificate of Analysis. Catalogue numbers follow the CAS-based scheme NSA-157115-85-0 with the pack size appended, for example NSA-157115-85-0-10G. For reference-standard work the 1 g and 5 g sizes are the usual choice; the larger sizes exist for laboratories running extended method-development or stability programmes.

What are the hazards?

There is effectively no classification. The ECHA inventory carries a single notification for this substance, and that notification states that it does not meet GHS hazard criteria, so no signal word, hazard statement or precautionary statement has been assigned and this page prints no pictogram. One company saying a substance is not hazardous is the thinnest possible evidential basis and is not a safety assessment. Handle the material as a biologically active organic solid of unknown toxicity, with gloves, eye protection and dust containment, and record the thinness of the data in the workplace risk assessment. The Safety Data Sheet shipped with the batch is the controlling document.

17. How this page is sourced and verified

Limitations named directly

1. The compound registry contains no experimental physicochemistry. Every value in section 3 is computed. The measured solid-state data in section 5 come from a single cited study, not from the registry.
2. The hazard classification rests on one notification, and that notification asserts the absence of hazard. Section 10 explains why that is the weakest possible basis rather than a reassurance.
3. The primary pharmacology comes from essentially one institute, with overlapping authorship across three decades and little independent replication. Section 12 says so in place.
4. No published method distinguishes the stereoisomers of this compound, and no circular dichroism or optical rotatory dispersion data are deposited. The identity risk described in section 6.2 therefore currently has no published analytical solution.
5. The current Russian regulatory position was not verified from a primary source and is not asserted anywhere on this page.
6. The bibliography is short — sixteen sources — because the primary literature on this compound is concentrated and finite. Padding it would misrepresent the state of knowledge.

Not yet on this page

This page does not carry a named author with stated professional qualifications, a named technical reviewer, or laboratory data generated in-house for a specific batch — no chromatogram, no spectrum, no measured retention or stereochemical purity of our own. For this substance the last of those is the most conspicuous: the identity problem set out in section 6.2 is precisely the kind that in-house measurement would close.

18. References

Citations follow the Chicago author–date convention. All external links carry rel="nofollow". Access to full texts is governed by the policies of the respective publishers.

Registry and regulatory sources

1. National Center for Biotechnology Information. 2026. "PubChem Compound Summary for CID 180496, Omberacetam." PubChem. Accessed August 22, 2026. https://pubchem.ncbi.nlm.nih.gov/compound/180496.
2. U.S. Food and Drug Administration. 2026. "Global Substance Registration System: UNII 4QBJ98683M, Omberacetam." Accessed August 22, 2026. https://gsrs.ncats.nih.gov/ginas/app/beta/substances/4QBJ98683M.
3. World Anti-Doping Agency. 2025. World Anti-Doping Code International Standard: Prohibited List 2026. Effective 1 January 2026. https://www.wada-ama.org/en/prohibited-list.
4. Minister Zdrowia. 2024. Obwieszczenie Ministra Zdrowia z dnia 17 czerwca 2024 r. w sprawie ogłoszenia jednolitego tekstu rozporządzenia Ministra Zdrowia w sprawie wykazu substancji psychotropowych, środków odurzających oraz nowych substancji psychoaktywnych. Dziennik Ustaw 2024, poz. 1139. https://eli.gov.pl/eli/DU/2024/1139.
5. U.S. Drug Enforcement Administration. 2014. "National Forensic Laboratory Information System: Omberacetam, drug category Other Substances, added May 2014." Annotation reproduced in the PubChem record for CID 180496. https://www.nflis.deadiversion.usdoj.gov/.
6. National Institutes of Health, Office of Dietary Supplements. 2026. "Dietary Supplement Label Database: products labelled as containing noopept / omberacetam." Accessed August 22, 2026. https://dsld.od.nih.gov/.

Solid-state chemistry, pharmaceutical analysis and standardisation

7. Araj, S. K., Ł. Szeleszczuk, T. Gubica, M. Zielińska-Pisklak, K. Bethanis, E. Christoforides, M. K. Dudek, and D. M. Pisklak. 2025. "Physicochemical and Structural Analysis of N-Phenylacetyl-L-prolylglycine Ethyl Ester (Noopept) — An Active Pharmaceutical Ingredient." Journal of Pharmaceutical and Biomedical Analysis 252: 116474. https://doi.org/10.1016/j.jpba.2024.116474.
8. Gusev, A. V., L. N. Grushevskaya, O. B. Stepanenko, N. I. Avdyunina, B. M. Pyatin, V. P. Lezina, and O. S. Anisimova. 2007. "Developing Analytical Methods for the Creation of the State Reference Sample of Noopept." Pharmaceutical Chemistry Journal 41 (12): 666–669. https://doi.org/10.1007/s11094-008-0037-6.
9. Grushevskaya, L. N., N. I. Avdyunina, B. M. Pyatin, K. V. Alekseev, L. M. Gaevaya, M. S. Sergeeva, M. E. Dudenkova, V. S. Klumova, and N. V. Tikhonova. 2011. "Pharmaceutical Analysis and Standardization of Noopept Tablets." Pharmaceutical Chemistry Journal 45 (6): 377–380. https://doi.org/10.1007/s11094-011-0638-3.
10. Cohen, P. A., B. Avula, Y.-H. Wang, I. Zakharevich, and I. Khan. 2021. "Five Unapproved Drugs Found in Cognitive Enhancement Supplements." Neurology: Clinical Practice 11 (3). https://doi.org/10.1212/CPJ.0000000000000960.

Chemistry, metabolism and pharmacology

11. Gudasheva, T. A., K. N. Kolyasnikova, E. A. Kuznetsova, S. A. Litvinova, N. N. Zolotov, T. A. Voronina, R. U. Ostrovskaya, and S. B. Seredenin. 2017. "N-Phenylacetylglycyl-L-Proline Ethyl Ester Converts into Cyclo-L-Prolylglycine Showing a Similar Spectrum of Neuropsychotropic Activity." Pharmaceutical Chemistry Journal 50 (11): 705–710. https://doi.org/10.1007/s11094-017-1516-4.
12. Gudasheva, T. A., S. S. Boyko, R. U. Ostrovskaya, T. A. Voronina, V. K. Akparov, S. S. Trofimov, G. G. Rozantsev, A. P. Skoldinov, V. P. Zherdev, and S. B. Seredenin. 1997. "The Major Metabolite of Dipeptide Piracetam Analogue GVS-111 in Rat Brain and Its Similarity to Endogenous Neuropeptide Cyclo-L-Prolylglycine." European Journal of Drug Metabolism and Pharmacokinetics 22 (3): 245–252. https://doi.org/10.1007/bf03189814.
13. Gudasheva, T. A., S. S. Boyko, V. Kh. Akparov, R. U. Ostrovskaya, S. P. Skoldinov, G. G. Rozantsev, T. A. Voronina, V. P. Zherdev, and S. B. Seredenin. 1996. "Identification of a Novel Endogenous Memory Facilitating Cyclic Dipeptide Cyclo-Prolylglycine in Rat Brain." FEBS Letters 391 (1–2): 149–152. https://doi.org/10.1016/0014-5793(96)00722-3.
14. Boiko, S. S., V. P. Zherdev, T. A. Gudasheva, S. A. Korotkov, and R. U. Ostrovskaya. 2001. "Pharmacokinetics of the New Potential Dipeptide Nootrope GVS-111 and Related Metabolites in Rat Brain." Pharmaceutical Chemistry Journal 35 (9): 474–476. https://doi.org/10.1023/a:1014082406443.
15. Vakhitova, Yu. V., S. V. Sadovnikov, S. S. Borisevich, R. U. Ostrovskaya, T. A. Gudasheva, and S. B. Seredenin. 2016. "Molecular Mechanism Underlying the Action of Substituted Pro-Gly Dipeptide Noopept." Acta Naturae 8 (1): 82–89. https://doi.org/10.32607/20758251-2016-8-1-82-89.
16. Seredenin, S., R. Ostrovskaya, T. Gudasheva, J. Halikas, T. Voronina, S. Trofimov, T. Garibova, H. Valdman, H. Kravchenko, and D. Overstreet. 1994. "A Novel Cognitive Enhancing Substance GVS-111." Neuropsychopharmacology 11 (4): 283. https://doi.org/10.1038/sj.npp.1380206. (Single-page item; treated as a conference communication rather than a full report.)