Everything below concerns N-acetyl Semax. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-07-07. Where a claim depends on a specific study, the study is described rather than over-claimed.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
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.
| Property | Value | Notes |
|---|---|---|
| Typical analytical method | Reversed-phase HPLC with UV detection | Separates target peptide from truncated and oxidised forms |
| Identity confirmation | LC-MS or ESI-MS | Compares observed and calculated molecular ion |
| Primary degradation route | Methionine oxidation | Forms the sulfoxide; monitored as an early-eluting peak |
| Short-term storage | 2 to 8 degrees Celsius | Applies to working vials and reconstituted portions |
| Common synonyms | ACTH(4–10) analogue, MEHFPGP | Descriptive names used in laboratory catalogues |
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
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.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
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.
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
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.
== Research == Anastrozole is surprisingly ineffective at treating gynecomastia, in contrast to selective estrogen receptor modulators like tamoxifen. Anastrozole was under development for the treatment of female infertility but did not complete development and hence was never approved for this indication. An anastrozole and levonorgestrel vaginal ring (developmental code name BAY 98–7196) was under development for use as a hormonal contraceptive and treatment for endometriosis. Development was discontinued in November 2018, and the formulation was never marketed. Anastrozole increases testosterone levels in males and has been studied as an alternative method of androgen replacement therapy in men with hypogonadism. However, there are concerns about its long-term influence on bone mineral density in this patient population, as well as other adverse effects.
=== Francis Crick Medal and Lecture === The Francis Crick Medal and Lecture was established in 2003 following an endowment by his former colleague, Sydney Brenner, joint winner of the 2002 Nobel Prize in Physiology and Medicine. The lecture is delivered annually in any field of biological sciences, with preference given to the areas in which Francis Crick himself worked. Importantly, the lectureship is aimed at younger scientists, ideally under 40, or whose career progression corresponds to this age. As of 2019, Crick lectures have been delivered by Julie Ahringer, Dario Alessi, Ewan Birney, Simon Boulton, Jason Chin, Simon Fisher, Matthew Hurles, Gilean McVean, Duncan Odom, Geraint Rees, Sarah Teichmann, M. Madan Babu and Daniel Wolpert.
== Multiplayer mods == Arg! – A pirate-themed deathmatch mod focused on melee combat. PC Zone gave a rating of two out of five. PC PowerPlay wrote: "All new weapons, maps and outstanding pirate features make this a must download." Action Half-Life – A team-based multiplayer mod developed as part of the popular series of "Action"-based mods, designed to emulate the feel of an action movie. Members of the development team had previously worked with developers of Counter-Strike on the mod Action Quake 2. Battle of the Millenium – A superhero-themed class-based deathmatch mod. Six characters are included: Batman, Mega Man, Son Goku, Spawn, Spider-Man, and Superman. In addition of standard weapons, each character has four special powers. Gen4 called the graphics convincing but said the mod is unbalanced since the characters are not equal in power. Blood for Honor – A medieval fantasy deathmatch mod. It includes nine different classes to choose from. .NetGamer called it an interesting mod with an RPG touch. Canned Tuna – Deathmatch mod with five game modes. One of them is called "Gib The Llama" where players are turned into llamas after every odd-numbered respawn. In every game mode players have five weapons with unlimited ammunition (except trip mines). It received a score of three out of five from PC Zone, calling it a weird but incohesive gaming experience. The mod was said to be unpopular with few servers running it. Cold Ice – Features fast-paced gameplay (aided by tools like a jetpack and a grappling hook) and revamps all of the weapons and the color scheme to icy blue.
All pages with titles containing ACDC or ACDCs All pages with titles beginning with ACDC AC/DC (disambiguation) ACDC domain, AP2-Coincident Domain mainly at the Carboxy-terminus, a protein domain found in malaria parasites and its evolutionary relatives ACDC Lane, a street in Melbourne named after the band AC/DC ACDSee, a shareware image viewer program Alternating current (AC) electricity Direct current (DC) electricity
Sources: en.wikipedia.org
== Signs and symptoms == Sun-sensitive rash with prominent poikiloderma and telangiectasias Juvenile cataracts Saddle nose Congenital bone defects, including short stature and radial ray anomalies such as absent thumbs Hair growth problems (absent eyelashes, eyebrows and/or hair) Hypogonadism has not been well documented Hypodontia Calcium problems (not documented in journals) Ear problems (not documented in journals but identified by patients in support groups) Produces osteosarcoma The skin is normal at birth. Between 3 and 6 months of age, the affected carrier develops poikiloderma on the cheeks. This characteristic "rash" that all RTS carriers have can develop on the arms, legs and buttocks. "Poikiloderma consists of areas of increased and decreased pigmentation, prominent blood vessels, and thinning of the skin."
WAY-204688, also known as SIM-688, is a synthetic nonsteroidal estrogen and nuclear factor κB (NF-κB) inhibitor which was originated by ArQule and Wyeth and was under development by Wyeth for the treatment of rheumatoid arthritis, non-specific inflammation, and sepsis but was never marketed. It is a "pathway-selective" estrogen receptor (ER) ligand which inhibits NF-κB with an IC50Tooltip half-maximal inhibitory concentration of 122 nM and with maximal inhibition relative to estradiol of 94%. Inhibition of NF-κB by WAY-204688 appears to be dependent on agonism of the ERα, as it is reversed by the ERα antagonist fulvestrant, but is not dependent on the ERβ. In contrast to the case of NF-κB inhibition, WAY-204688 produces only slight elevation of creatine kinase in vitro, a measure of classical estradiol effects. It reached phase I clinical trials prior to the discontinuation of its development.
During World War I and World War II, cigarettes were rationed to soldiers. During the Vietnam War, the U.S. included cigarettes with C-ration meals; however, cigarettes were removed from U.S. military rations in 1975. During the second half of the 20th century, the adverse health effects of tobacco smoking started to become widely known and printed health warnings became common on cigarette packets. Graphical cigarette warning labels are a more effective method to communicate to the public the dangers of cigarette smoking. Canada, Mexico, Belgium, Denmark, Sweden, Thailand, Malaysia, India, Pakistan, Australia, Argentina, Brazil, Chile, Peru, Greece, the Netherlands, New Zealand, Norway, Hungary, the United Kingdom, France, Romania, Singapore, Egypt, Jordan, Nepal and Turkey all have both textual warnings and graphic visual images displaying, among other things, the damaging effects tobacco use has on the human body. The United States has implemented textual but not graphical warnings. The cigarette has evolved much since its conception; for example, thin bands that travel transverse to the "axis of smoking" (thus forming circles along the length of the cigarette) are alternate sections of thin and thick paper to facilitate effective burning when being drawn, and retard burning when at rest. Synthetic particulate filters may remove some tar before it reaches the smoker. The "holy grail" for cigarette companies has been a cancer-free cigarette. The closest historical attempt was produced by scientist James Mold.
Sources: en.wikipedia.org
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.
Oxidation of the methionine residue to the sulfoxide is a frequently reported change, and it usually appears as an earlier-eluting peak in reversed-phase chromatography. Backbone hydrolysis products can also accumulate in aqueous solution.
Liquid chromatography coupled with mass spectrometry is the usual approach, because the observed molecular ion can be compared with a calculated mass of about 813.9 Da. Retention time alone does not establish identity.
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.