A practical reference on peptide synthesis: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-11-17 and is reviewed periodically as new material appears.
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 work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
=== Laminin G === The laminin globular (G) domain, also known as the LNS (Laminin-alpha, Neurexin and Sex hormone-binding globulin) domain, is on average 177 amino acids in length and can be found in one to six copies in various laminin family members as well as in a large number of other extracellular proteins. For example, all laminin alpha-chains have five laminin G domains, all collagen family proteins have one laminin G domain, the CNTNAP proteins have four laminin G domains, while neurexin 1 and 2 each hold six laminin G domains. On average, approximately one quarter of the proteins that hold laminin G domains is taken up by these laminin G domains themselves. The smallest laminin G domain can be found in one of the collagen proteins (COL24A1; 77 AA) and the largest domain in TSPEAR (219 AA). The exact function of the Laminin G domains has remained elusive, and a variety of binding functions has been ascribed to different Laminin G modules. For example, the laminin alpha1 and alpha2 chains each have five C-terminal laminin G domains, where only domains LG4 and LG5 contain binding sites for heparin, sulphatides and the cell surface receptor dystroglycan. Laminin G-containing proteins appear to have a wide variety of roles in cell adhesion, signalling, migration, assembly and differentiation.
gas chromatography A type of chromatography commonly used in analytical chemistry to isolate and analyze chemical compounds that can be vaporized without decomposition. Gas chromatography is often used to test the purity of substances, to identify unknown substances, and to measure the relative amounts of the different components of mixtures.
=== May === 3 May – Astronomers from the University of Warwick report 118 new confirmed exoplanets, with a further 2,000 "high-quality" candidates, detected using machine learning applied to data from NASA's Transiting Exoplanet Survey Satellite (TESS). 4 May The discovery of a thin atmosphere on the trans-Neptunian object (612533) 2002 XV93 is announced. A study published in Communications Sustainability finds that utility-scale solar power and wind power generally provide greater climate and public health benefits per dollar than direct air capture (DAC), based on modelling across 22 U.S. grid regions through 2050. The authors conclude that DAC becomes competitive mainly under a breakthrough scenario in which energy use falls from 5,500 to 800 kWh and cost from US$1,000 to US$100 per tonne of CO2 captured. A meta-analysis of over 20,000 participants concludes that drugs targeting amyloid beta peptides do not meaningfully slow progression of Alzheimer's disease. 6 May – A study in npj Space Exploration, using radar data from India's Chandrayaan-2 orbiter, reports strong evidence for subsurface water ice in four doubly-shadowed craters near the lunar south pole. 8 May – A study published in Aging Cell reports that the exceptional-longevity-associated APOE ε2 allele is associated with enhanced DNA-damage response and repair pathways in human neurons.
In February 2015, Labcorp acquired Covance for $6.1 billion. In October 2015, Labcorp acquired Safe Foods International Holdings and its two operating companies, International Food Network and The National Food Laboratory, expanding its capabilities in food and beverage product-development and product-integrity. In March 2016, Labcorp acquired Pathology Inc., a provider of reproductive donor testing as well as anatomic, molecular and digital pathology services focused on women's health. In September 2016, Labcorp acquired Sequenom for $371 million including debt, expanding its operations in Europe and Asia. In October 2016, Labcorp acquired ClearPath Diagnostics, a provider of laboratory diagnostic services in the Northeastern United States, from Shore Capital Partners. In May 2017, Labcorp acquired Pathology Associates Medical Laboratories from Providence Health & Services and Catholic Health Initiatives. In September 2017, Labcorp acquired Chiltern, a contract research organization (CRO), for $1.2 billion, and contributed it to Covance. In 2019, Labcorp acquired Wellness Corporate Solutions, a workplace wellness company.
Sources: en.wikipedia.org
A hangover is the experience of various unpleasant physiological and psychological effects usually following the consumption of alcohol, such as wine, beer, and liquor. Hangovers can last for several hours or for more than 24 hours. Typical symptoms of a hangover may include headache, drowsiness, concentration problems, dry mouth, dizziness, fatigue, gastrointestinal distress (e.g., nausea, vomiting, diarrhea), absence of hunger, light sensitivity, depression, sweating, hyper-excitability, irritability, and anxiety (often referred to as "hangxiety").
== Veterinary use == BCG is used in England by licensed individuals to vaccinate wild badgers by trapping and release. It reduces new bovine TB infection rates by up to 76% in vaccinated badgers. It also exhibits a herd immunity effect, where a badger social group with more than one-third vaccination coverage shows up to 79% lower new infection in cubs. There is no evidence that vaccinated badgers excrete live BCG into the environment. Vaccination initiatives have been lead both by the government's Animal and Plant Health Agency and by private individuals and groups such as farmers seeking to protect their livestock and landowners seeking to clear their land of TB. BCG vaccination in cattle has completed a phase II trial in the UK with satisfactory results. The phase III trial started in 2025.
Abuse of fenethylline using the former brand name Captagon is common in the Middle East, and counterfeit versions of the drug continue to be available despite its illegality. Fenethylline is much less common outside of the Middle East, to the point that police may not recognize the drug. Fenethylline production and export were a significant industry sponsored by Bashar al-Assad's government, with revenue from its exports contributing more than 90% of its foreign currency. After the fall of al-Assad's government in Syria, Captagon trade fell by around 90%. The Assad regime's annual fenethylline revenues were estimated to have been worth US$57 billion in 2022, about three times the total trade of the entire Mexican illicit drug market. Later research demonstrated that this assistance, largely the financing of production and sponsoring networks of drug dealers, was undertaken through the former Assad regime's Military Intelligence Directorate (Syria). In July 2019 in Lebanon, captagon was sold for $1.50 to $2.00 a pill. In 2021 in Syria, low-quality pills were sold locally for less than $1, while high-quality pills are increasingly smuggled abroad and may cost upwards of $14 each in Saudi Arabia. Many of these counterfeit "Captagon" tablets contain other amphetamine derivatives that are easier to produce, but are pressed and stamped to look like Captagon pills. Some counterfeit Captagon pills analysed do contain fenethylline, indicating that illicit production of the drug continues to take place.
Phenoloxidase system is a major defense system in many invertebrates which ultimately leads to melanization of pathogens and damaged tissues. The process of melanization depends on activation of the enzyme phenoloxidase (PO) which is controlled by the prophenoloxidase (proPO) activation system. During activation of the proPO cascade, many other immune reactions are produced, such as cytotoxic, opsonic and encapsulation activities. The phenoxidase cascade plays an important role in invertebrates (especially insects) in three physiologically important processes: immune reactions, sclerotization of the cuticle and wound healing.
Angels of presence, praising God Seraphim – spirits of love Cherubim – spirits of harmony Thrones – record keepers of universal laws Angels of government, spreading light Dominions – spirits of wisdom and knowledge Virtues – angels of movement and free will Powers – angels of form and space Angels of revelation, able to communicate with humans Principalities – angels of time and personality Archangels – powerful angels superior to ordinary angels Angels – governors of spirits of nature
Sources: en.wikipedia.org
=== MAGA fallout over non-release of Jeffrey Epstein files === On July 7, 2025, the FBI issued a two-page statement saying they had concluded that infamous sex offender Jeffrey Epstein did not possess a "client list", even though Attorney General Pam Bondi had hinted in February that such a document was on her desk. Several right-wing media personalities were highly critical of the decision. And per mainstream sources, FBI Deputy Director Dan Bongino is considering resigning and had been feuding with Bondi. One of the reasons given for the non-release is the privacy of the victims. At a White House press conference on the same day, President Trump asked a reporter, "Are you still talking about Jeffrey Epstein?" In late-July 24, several Senator Republicans spoke in favor of releasing the information. Lindsey Graham (Republican-South Carolina) said, "The idea that Trump did something nefarious and Biden sat on it for four years, It's hard to believe. Just put it out. Let people look at it." Josh Hawley (R-Missouri) said, "Anybody who ever met him is going to be mentioned, so I don't think that's a big deal ... but nor is it a reason to withhold the documents." Thom Tillis (R-North Carolina) said, "I'm where I've been every time you always ask me this question. Release the damn files." On September 3, 2025, at an at large outside press conference on the Capitol steps, legislators were joined by nearly a dozen women who state they had been abused by convicted offender Epstein.
=== Mechanical stimulation === Mechanical stimulation of angiogenesis is not well characterized. There is a significant amount of controversy with regard to shear stress acting on capillaries to cause angiogenesis, although current knowledge suggests that increased muscle contractions may increase angiogenesis. This may be due to an increase in the production of nitric oxide during exercise. Nitric oxide results in vasodilation of blood vessels. Beyond fluid shear stress, the water channel AQP1 contributes to the mechanical expansion of the cell membrane during migration. By facilitating localized water influx at the leading edge, AQP1 creates the hydrostatic pressure necessary to drive membrane protrusions, which is a critical physical step in the formation of new vascular sprouts.
== Sources == This article incorporates text from a free content work. Licensed under CC BY-SA 3.0 (license statement/permission). Text taken from The State of Food and Agriculture 2019. Moving forward on food loss and waste reduction, in brief, 24, FAO, FAO.
The two-star award was restored a year later in the 2009 Michelin Guide, as had been predicted by a number of Bosi's fellow chefs including Tom Aikens, Antonin Bonnet and Richard Corrigan. Sat Bains went a step further and said "I would love to see Claude Bosi regain his second star at Hibiscus and win his third in time. He's probably the best chef I know." The restaurant closed permanently in 2016, two days prior to the announcement of the 2017 Michelin Guide for UK and Ireland.
== Structure == Theoretical calculations have predicted the existence of metastable O4 molecules with two different shapes: a "puckered" square like cyclobutane or S4, and a "pinwheel" with three oxygen atoms surrounding a central one in a trigonal planar formation similar to boron trifluoride or sulfur trioxide. It was previously pointed out that the "pinwheel" O4 molecule should be the natural continuation of the isoelectronic series BO3−3, CO2−3, NO−3, and analogous to SO3; that observation served as the basis for the mentioned theoretical calculations.
Sources: en.wikipedia.org
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.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.