The short version of heptapeptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-01-06. Anything still debated is marked as such rather than presented as settled.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
| Property | Value | Notes |
|---|---|---|
| Molecular weight | ~813.9 Da (free heptapeptide) | N-acetylated form is about 42 Da heavier |
| Residue count | 7 (heptapeptide) | Four residues from ACTH(4-10), three added |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility class | Freely soluble in water | Also dissolves in DMSO and polar organic solvents |
| Related parent fragment | ACTH(4-10) | Parent motif is Met-Glu-His-Phe |
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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The narrower Russell Top 50 Mega Cap Index consists of the 50 largest companies in the Russell 3000 at the time of index reconstitution. As of April 30, 2026, the Russell Top 50 Mega Cap Index contained 51 constituents, with market caps ranging from $216.6 billion to $4.85 trillion. The even narrower Russell Top 10 Index consists of the 10 largest companies in the Russell 3000 at the time of index reconstitution. As of May 29, 2026, the Russell Top 10 Index contained 11 constituents, with market caps ranging from $873 billion to $4.93 trillion. A 2025 article by S&P Dow Jones Indices describes its own S&P 100, S&P 500 Top 50 (ticker: SP5T5), S&P 500 Top 20 (ticker: SP5T2), and S&P 500 Top 10 (ticker: SP5T1) indices as "mega-cap indices". As of May 29, 2026, the S&P 100 index's methodology required a minimum market cap of $22.7 billion, and the index's 101 constituents had actual market caps ranging from $55.1 billion to $5.13 trillion. As of May 29, 2026, the S&P 500 Top 50 Index contained 51 constituents, with market caps ranging from $92.3 billion to $5.13 trillion. Invesco issues an index ETF (NYSE Arca: XLG) that tracks the S&P 500 Top 50 Index. As of May 29, 2026, the S&P 500 Top 20 Index contained 21 constituents, with market caps ranging from $316 billion to $5.13 trillion. The S&P 500 Top 20 Select Index (ticker: SPXT2SUP) is a capped variant of the S&P 500 Top 20 Index, limiting any single company's weight in the index to a maximum of 22.5%, and limiting companies with weights above 4.5% to collectively constitute at most 48% of the index's weight.
== Other forms of copper sulfate == Anhydrous copper(II) sulfate can be produced by dehydration of the commonly available pentahydrate copper sulfate. In nature, it is found as the very rare mineral known as chalcocyanite. The pentahydrate also occurs in nature as chalcanthite. Other rare copper sulfate minerals include bonattite (trihydrate), boothite (heptahydrate), and the monohydrate compound poitevinite. There are numerous other, more complex, copper(II) sulfate minerals known, with environmentally important basic copper(II) sulfates like langite and posnjakite.
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The Leidenfrost point signifies the onset of stable film boiling. It represents the point on the boiling curve where the heat flux is at the minimum and the surface is completely covered by a vapor blanket. Heat transfer from the surface to the liquid occurs by conduction and radiation through the vapour. In 1756, Leidenfrost observed that water droplets supported by the vapor film slowly evaporate as they move about on the hot surface. As the surface temperature is increased, radiation through the vapor film becomes more significant and the heat flux increases with increasing excess temperature. The minimum heat flux for a large horizontal plate can be derived from Zuber's equation,
Sources: en.wikipedia.org
In 2005, Sean Kinney came up with the idea of doing a benefit concert for the victims of the tsunami disaster that struck South Asia in 2004. Kinney made calls to his former bandmates, as well as friends in the music community, such as former Alice in Chains manager Susan Silver. Kinney was surprised by the enthusiastic response to his idea. On February 18, 2005, Jerry Cantrell, Mike Inez, and Sean Kinney reunited to perform for the first time in nine years at K-Rock Tsunami Continued Care Relief Concert in Seattle. The band featured Damageplan vocalist Pat Lachman, as well as other special guests including Maynard James Keenan of Tool, Wes Scantlin of Puddle of Mudd and Ann Wilson of Heart. A few months after that experience, the band called Susan Silver and Cantrell's manager Bill Siddons and said they wanted to tour as Alice in Chains again. Alice in Chains was approached by the producers of the CBS reality show Rock Star about being featured on its second season, but the band turned the offer down. In the show, aspiring singers competed to become the lead vocalist of a featured group. On March 10, 2006, the surviving members performed at VH1's Decades Rock Live! concert, honoring fellow Seattle musicians Ann and Nancy Wilson of Heart. They played "Would?" with vocalist Phil Anselmo of Pantera and Down and bass player Duff McKagan of Guns N' Roses and Velvet Revolver, and at the end of the performance Cantrell dedicated the show to Layne Staley and the late Pantera and Damageplan guitarist Dimebag Darrell.
The Canadian Armed Forces provides each soldier with a complete pre-cooked meal known as the Individual Meal Pack (IMP), packaged inside a heavy-duty folding paper bag. There are 5 breakfast menus, 6 lunch menus, and 6 supper menus. Canadian rations provide generous portions and contain a large number of commercially available items. The main meal is precooked and ready-to-eat, packed in heavy-duty plastic-foil retort pouches boxed with cardboard. Typically, the ration contains a meal item (beans and wiener sausages, scalloped potatoes with ham, smoked salmon fillet, macaroni and cheese, cheese omelette with mushrooms, shepherd's pie, etc.), wet-packed (sliced or mashed) fruit in a boxed retort pouch, and depending on the meal a combination of instant soup or cereal, fruit drink crystals, jam or cheese spread, peanut butter, honey, crackers, bread (bun) compressed into a retort pouch, coffee and tea, sugar, commercially available chocolate bars and hard candy, a long plastic spoon, paper towels and wet wipes. Canada also makes limited use of a Light Meal Pack containing dried meat or cheese, dried fruit, a granola bar, a breakfast cereal square, a chocolate bar, hard candy, hot cocoa mix, tea, and two pouches of instant fruit drink. Canadian ration packs also contain a book of cardboard matches.
Natural freshwater diatomaceous earth is preferred by many researchers over chromic oxide, which has been widely used for the same purpose, the latter being a known carcinogen and, therefore, a potential hazard to research personnel.
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Sources: en.wikipedia.org
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.
Semax is a synthetic analog of the ACTH(4-10) fragment rather than a copy of the full hormone. Truncation plus the added tail removes the steroidogenic portion of ACTH. That distinction explains why it is studied for nervous-system effects instead of adrenal stimulation.
It is registered as a prescription product in Russia and has been used there clinically, chiefly by the intranasal route. No approval exists in the United States or the European Union. Availability elsewhere typically falls under research-chemical distribution, with varying purity documentation.
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.