The short version of heptapeptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-01-30. Anything still debated is marked as such rather than presented as settled.
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.
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.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
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.
| 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 |
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
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.
By choosing porous graphitic carbon as a stationary phase for liquid chromatography, even non derivatized glycans can be analyzed. Detection is here done by mass spectrometry, but in instead of MALDI-MS, electrospray ionisation (ESI) is more frequently used.
K84 produces a bacteriocin (agrocin 84) which is an antibiotic specific against related bacteria, including A. tumefaciens. This method, which was successful at controlling the disease on a commercial scale, had the risk of K84 transferring its resistance gene to the pathogenic Agrobacteria. Thus, in the 1990s, a deletion mutant strain based on K84, known as K1026, was created. This strain is just as successful in controlling crown gall as K84 without the caveat of resistance gene transfer.
Devices that integrate (multiple) laboratory functions on a single chip of only millimeters to a few square centimeters in size and that are capable of handling extremely small fluid volumes down to less than picoliters.
=== Brand names === EMP is most commonly marketed under the brand names Estracyt and Emcyt, but has also been sold under a number of other brand names, including Amsupros, Biasetyl, Cellmustin, Estramustin HEXAL, Estramustina Filaxis, Estranovag, Multosin, Multosin Injekt, Proesta, Prostamustin, and Suloprost.
Sources: en.wikipedia.org
Carbetocin, sold under the brand names Pabal among others, is a medication used to prevent excessive bleeding after childbirth, particularly following Cesarean section. It appears to work as well as oxytocin. Due to it being less economical than other options, use is not recommended by NHS Scotland. It is given by injection into a vein or muscle. Side effects differ little from that of no treatment or placebo. Use is not recommended in people with epilepsy or eclampsia. Carbetocin is a manufactured long acting form of oxytocin. It works by activating the oxytocin receptor which causes the uterus to contract. Carbetocin was synthesized before 1971 at the Czechoslovak Institute of Organic Chemistry and Biochemistry and was first described by 1974. It was approved for medical use in Canada and the United Kingdom in 1997. It is on the World Health Organization's List of Essential Medicines. It is not available in the United States or Japan.
In captivity, these are not picky fish; They readily feed on different types of frozen, freeze-dried and live foods, such as tubifex worms, bean beetles (and larvae), bloodworms, brine shrimp, daphnia, flour beetles, krill, springtails, small or finely-chopped earthworms, black soldier fly larvae and cultured wingless fruit flies (Drosophila melanogaster). In particular, the tubifex worms and fruit flies are high in protein and nutrients, resulting in highly significant growth. A predominantly live food diet also provides nutrients for better reproductive performance. Ultimately, food variety is key, for health, but also for mimicking natural feeding habits. It was first described by Ferdinand Schultze in a catalog of specimens at the Zoological Museum of the Royal University of Berlin, published by Hinrich Lichtenstein in 1823. First import to Europe (Germany) by C.Ziggelkow, Hamburg in 1909 The genome of the angelfish was sequenced and assembled in 2022 by Indeever Madireddy, a high school student.
Sirtuin-activating compounds (STAC) are chemical compounds having an effect on sirtuins, a group of enzymes that use NAD+ to remove acetyl groups from proteins. They are caloric restriction mimetic compounds that may be helpful in treating various aging-related diseases.
== Variation == Many genetic variants of the GC gene are known. They produce 6 main haplotypes and 3 main protein variants (Gc1S, Gc1F and Gc2). The genetic variations are associated with differences in circulating 25-hydroxyvitamin D levels. They have been proposed to account for some of the differences in vitamin D status in different ethnic groups, and have been found to correlate with the response to vitamin D supplementation.
Zverev is an all-court player and does not aim to be better on any surface in particular. He has said, "I feel like I can play on all surfaces. I've been to two finals or won tournaments on every single surface. I don't feel like I have to focus on one... I feel like I have good chances at all of them." Toni Nadal, the uncle and coach of Rafael Nadal, has praised his ability on hard courts in particular, saying, "His best surface is, in my eyes, the hard court, because he moves better than he does on clay." Six of Zverev's first ten titles came on hard courts, while the other four were on clay. As of 2024, he has yet to win a title on grass, but has reached two finals and defeated Federer on that surface. His best grass tournament remains Halle, in his home country. Zverev has the ability to serve-and-volley as well. His older brother Mischa is regarded as the biggest proponent of this playing style on the modern tour. Although Zverev does not employ this technique as often as his brother, he has shown it can be effective in big matches such as the Madrid Masters final against Dominic Thiem, a player who rarely comes to the net. Zverev's volley and overhead technique are regarded as some of his biggest weaknesses. Zverev was tall but skinny and not very muscular when growing up. His fitness trainer Jez Green has focused on making him stronger and set a goal for him to add 4 kilograms (8.8 lb) of muscle each year.
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.
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.