This is a working overview of anti-doping, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-01-21 and is reviewed periodically as new material appears.
SR9009 is a synthetic small molecule that acts on the nuclear receptors REV-ERBα and REV-ERBβ. These receptors are part of the circadian clock machinery and normally repress transcription of certain target genes. In laboratory research, SR9009 is used as a chemical tool to study how REV-ERB activity influences metabolism, inflammation, and daily biological rhythms. The compound is not an approved medicine, and its effects in humans remain largely uncharacterized. It is often described as an investigational agent rather than a therapeutic product.
REV-ERB proteins typically suppress gene expression by recruiting corepressor complexes to DNA response elements. SR9009 binds these receptors and strengthens that repressive action in cell-based assays. Studies in rodents have reported changes in lipid handling, mitochondrial function, and exercise capacity after treatment. Such findings are often cited as evidence for metabolic effects, but species differences and limited pharmacokinetic data make direct translation to humans uncertain. Researchers continue to examine which effects are robust and which depend on specific experimental conditions.
SR9009 is frequently discussed alongside other REV-ERB ligands, including synthetic agonists and natural heme-related molecules. Its selectivity for REV-ERB over related nuclear receptors has been measured in binding and reporter assays, though off-target activity at higher concentrations is possible. The compound is prohibited in sport by the World Anti-Doping Agency, and it is not approved for any medical use in major jurisdictions. Products sold online may be labeled as research chemicals, and their identity and purity are not guaranteed by regulatory review.
Analytical identification and purity assessment often use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Liquid chromatography–tandem mass spectrometry is used to detect and quantify SR9009 in biological matrices, including urine and blood, for anti-doping or pharmacokinetic studies. Nuclear magnetic resonance spectroscopy can confirm molecular structure. Stability depends on form and storage: the solid is generally more stable than solutions, and repeated freeze–thaw cycles may degrade samples. Purity is typically reported as a percentage from a certificate of analysis.
Regulatory treatment of SR9009 varies by country and context. It is not approved as a therapeutic drug by agencies such as the United States Food and Drug Administration or the European Medicines Agency. Sports authorities list it as a prohibited substance; the World Anti-Doping Agency classifies it among hormone and metabolic modulators. Legal status for personal possession or sale differs across jurisdictions, and some countries may restrict it under analog or research chemical laws. Buyers who seek verified material often rely on independent laboratory testing because online product labels may not match contents.
Laboratory samples of SR9009 are typically handled as research chemicals rather than pharmaceuticals. Suppliers usually state that the material is for research use only and not for human or veterinary administration. Storage recommendations generally call for a freezer at approximately −20 °C, protection from light, and a desiccated environment. The solid is often described as a white to off-white powder. Solubility is commonly reported in organic solvents such as dimethyl sulfoxide and ethanol, with low solubility in water.
| Property | Value | Notes |
|---|---|---|
| Common name | SR9009 | Also marketed informally as Stenabolic |
| Chemical class | Synthetic REV-ERB agonist | Binds REV-ERBα and REV-ERBβ |
| Molecular formula | C24H30ClN3O4S | Approximate molecular weight 492 g/mol |
| CAS Registry Number | 1379686-30-2 | Identifier for the parent compound |
| Regulatory status | Not approved for human use | Prohibited in sport by WADA |
SR9009 is supplied as a solid research chemical, often in milligram quantities. Laboratories typically weigh it in a controlled environment because fine powders can disperse. Stock solutions are commonly prepared in dimethyl sulfoxide and stored in small aliquots to reduce freeze-thaw cycles. Personal protective equipment and chemical fume hoods are standard when handling unknown or potent compounds. These practices address laboratory safety rather than human use.
Identity and purity of SR9009 samples are usually checked with chromatographic and spectrometric methods. High-performance liquid chromatography can separate the compound from related impurities, while mass spectrometry provides molecular mass confirmation. Nuclear magnetic resonance spectroscopy may be used for structural verification in research settings. No single method proves biological activity, and certificates of analysis should be reviewed alongside raw data. Independent testing is often needed because online products vary widely.
SR9009 stability depends on temperature, moisture, light, and solvent. Solid material is generally kept cool and dry, while solutions may require protection from repeated warming and cooling. Degradation can appear as color changes, precipitate, or new chromatographic peaks. Researchers should follow supplier instructions and their own stability data. Long-term storage conditions for human use have not been established because the compound lacks approved clinical formulation.
SR9009 is a synthetic small molecule studied as an agonist of REV-ERB nuclear receptors. REV-ERB alpha and REV-ERB beta help regulate circadian rhythms and metabolic gene expression. In laboratory research, SR9009 has been used to probe how these receptors affect skeletal muscle, liver, and adipose tissue. The compound was identified in academic drug-discovery work and is often described in scientific literature by its chemical name and research code. It is not an approved medicine, and human clinical data remain limited or absent.
SR9009 binds REV-ERB receptors and alters their repressive activity on target genes. This action can change transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. In rodent studies, treated animals have shown changes in muscle oxidative capacity and exercise performance, though effects vary by dose, duration, and model. The precise molecular steps connecting receptor binding to whole-body outcomes are still an active area of investigation. Findings in animals do not automatically translate to humans.
Because REV-ERB receptors are core clock components, SR9009 has been examined for effects on daily rhythms as well as metabolism. Research has explored whether the compound can shift or reinforce circadian gene expression in tissues such as liver and muscle. Some studies report improved metabolic markers in obese or diabetic mice, while others show context-dependent responses. Questions remain about which effects are direct, which are secondary to timing, and how they might differ across species.
=== Chromatography === Internal standards are used in GC/MS and LC/MS to control for variability introduced by injection, sample preparation and other matrix effects. The ratio of peak areas between the internal standard and analyte is calculated to determine analyte concentration. A common type of internal standard is an isotopically labeled analogue of the analyte, which incorporates one or more atoms of 2H, 13C, 15N and 18O into its structure.
== Sources == Abu Izzedin, Nejla M. (1993) [1984]. The Druzes: A New Study of Their History, Faith, and Society (2nd ed.). Leiden and New York: Brill. ISBN 90-04-09705-8. Aytekin, E. Attila (2012). "Peasant Protest in the Late Ottoman Empire: Moral Economy, Revolt, and the Tanzimat Reforms". International Review of Social History. 57 (2): 191–227. doi:10.1017/S0020859012000193. hdl:11511/48429. Aalund, Flemming (1992). Vernacular Tradition and the Islamic Architecture of Bosra (PDF) (PhD). Copenhagen: The Royal Academy of Fine Arts School of Architecture. Batatu, H. (1999). Syria's Peasantry, the Descendants of Its Lesser Rural Notables, and Their Politics. Princeton University Press. ISBN 0-691-00254-1. Betts, Robert Brenton (1988). The Druze. New Haven: Yale University Press. ISBN 0-300-04100-4. Burkitt, Francis C. (1925). The Religion of the Manichees: Donnellan Lectures 1924. Cambridge, England: Cambridge University Press. OCLC 79046876. Chehab, Hafez (1994). "Reconstructing the Medici Portrait of Fakhr al-Din Maʾani". Muqarnas. 11: 117–124. doi:10.2307/1523213. JSTOR 1523213. Cross, Frank L.; Livingstone, E.A., eds. (2005). Oxford Dictionary of the Christian Church. Oxford University Press. ISBN 978-0-19-280290-3. Archived from the original on May 15, 2019. Retrieved October 8, 2020. Daftary, Farhad (2007). The Ismāʿı̄lı̄s: Their History and Doctrines (Second ed.). Cambridge: Cambridge University Press. ISBN 978-0-521-61636-2. Dana, Nissi (2003). The Druze in the Middle East: Their Faith, Leadership, Identity and Status. University of Michigan Press. p. 56.
For generic manufacturers, the act created a new approval mechanism, the Abbreviated New Drug Application (ANDA), in which the generic drug manufacturer need only demonstrate that their generic formulation has the same active ingredient, route of administration, dosage form, strength, and pharmacokinetic properties ("bioequivalence") as the corresponding brand-name drug. This act has been credited with, in essence, creating the modern generic drug industry. Concerns about the length of the drug approval process were brought to the fore early in the AIDS epidemic. In the mid and late 1980s, ACT-UP and other HIV activist organizations accused the FDA of unnecessarily delaying the approval of medications to fight HIV and opportunistic infections. Partly in response to these criticisms, the FDA issued new rules to expedite approval of drugs for life-threatening diseases, and expanded pre-approval access to drugs for patients with limited treatment options. All of the initial drugs approved for the treatment of HIV/AIDS were approved through these accelerated approval mechanisms. Frank Young, then commissioner of the FDA, was behind the Action Plan Phase II, established in August 1987 for quicker approval of AIDS medication. In two instances, state governments have sought to legalize drugs that the FDA has not approved.
== Applications == As DNA printing and DNA assembly methods have allowed commercial gene synthesis to become progressively and exponentially cheaper over the past years, artificial gene synthesis acts as an engineering tool for creating and designing new DNA sequences and protein functions. Besides synthetic biology, various research areas like those involving heterologous gene expression, vaccine development, gene therapy and molecular engineering, are also impacted by changes in DNA printing technology. The methods used for DNA printing and assembly have also enabled the use of DNA as an information storage medium.
Sources: en.wikipedia.org
Mycophenolate mofetil is the morpholino ethyl ester of mycophenolic acid; the ester masks the carboxyl group. Mycophenolate mofetil is reported to have a pKa values of 5.6 for the morpholino moiety and 8.5 for the phenolic group.
Drug inactivation or modification: for example, enzymatic deactivation of penicillin G in some penicillin-resistant bacteria through the production of β-lactamases. Drugs may also be chemically modified through the addition of functional groups by transferase enzymes. For example, acetylation, phosphorylation, or adenylation are resistance mechanisms to aminoglycosides. Acetylation is the most common and can affect a number of drug classes. Alteration of target- or binding site: for example, alteration of PBP—the binding target site of penicillins—in MRSA and other penicillin-resistant bacteria. Another protective mechanism found among bacterial species is ribosomal protection proteins. These proteins protect the bacterial cell from antibiotics that target the cell's ribosomes to inhibit protein synthesis. The mechanism involves the binding of the ribosomal protection proteins to the ribosomes of the bacterial cell, which in turn changes its conformational shape. This allows the ribosomes to continue synthesizing proteins essential to the cell while preventing antibiotics from binding to the ribosome to inhibit protein synthesis. Alteration of metabolic pathway: for example, some sulfonamide-resistant bacteria do not require para-aminobenzoic acid (PABA), an important precursor for the synthesis of folic acid and nucleic acids in bacteria inhibited by sulfonamides, instead, like mammalian cells, they turn to using preformed folic acid. Reduced drug accumulation: by decreasing drug permeability or increasing active efflux (pumping out) of the drugs across the cell surface.
The clinical signs of PAM are similar to bacterial and viral meningitis, including fever, neck stiffness, and severe headaches. Symptoms can progress to prolonged nausea, vomiting, and even seizures. The disease can progress to acute hemorrhagic necrotizing meningoencephalitis. After symptoms start, the patient typically dies within 1 to 18 days, typically about 5 days. A variable delay in treatment can be secondary to time intervals in multiple stages of care, including exposure to the exhibition of symptoms; arrival for treatment at a health care facility; workup of the diagnosis (initial diagnosis of likely bacterial meningitis); and finally, from diagnosis to initiation of recommended therapy. Successful treatment of PAM is rare; treatment can only be attempted after correct diagnosis, which relies on rapid recognition of the microorganism by medical technologists and pathologists. It is critical that medical technologists consistently provide timely CSF evaluation, explore the diagnosis of PAM, and look for amoebae in the setting of meningitis, especially in summer.
Sources: en.wikipedia.org
== Further reading == Serafini M, Cargnin S, Massarotti A, Pirali T, Genazzani AA (September 2020). "Essential Medicinal Chemistry of Essential Medicines". Journal of Medicinal Chemistry. 63 (18): 10170–10187. doi:10.1021/acs.jmedchem.0c00415. PMC 8007110. PMID 32352778. Stuart MC, Kouimtzi M, Hill SR, eds. (2009). WHO Model Formulary 2008. World Health Organization. hdl:10665/44053. ISBN 978-92-4-154765-9. The selection and use of essential medicines. Twentieth report of the WHO Expert Committee 2015 (including 19th WHO Model List of Essential Medicines and 5th WHO Model List of Essential Medicines for Children). Geneva: World Health Organization. 2015. hdl:10665/189763. ISBN 978-92-4-069494-1. ISSN 0512-3054. WHO technical report series; no. 994. The selection and use of essential medicines: report of the WHO Expert Committee, 2017 (including the 20th WHO Model List of Essential Medicines and the 6th Model List of Essential Medicines for Children). Geneva: World Health Organization. 2017. hdl:10665/259481. ISBN 978-92-4-121015-7. ISSN 0512-3054. WHO technical report series; no. 1006. The selection and use of essential medicines: report of the WHO Expert Committee on Selection and Use of Essential Medicines, 2019 (including the 21st WHO Model List of Essential Medicines and the 7th WHO Model List of Essential Medicines for Children). Geneva: World Health Organization. 2019. hdl:10665/330668. ISBN 978-92-4-121030-0. ISSN 0512-3054. WHO technical report series;1021. Organization WH (2019).
=== Linker === Between the reactive group and the tag, ABPs often include a linker / spacer / biorecognition element, which can tune probe solubility, steric accessibility, and substrate mimicry. Simple linkers may consist of alkyl chains or polyethylene glycol (PEG) spacers which adjust hydrophobicity and improve labeling across diverse proteomes. More complex designs incorporate biorecognition elements which can impart enzyme family or subfamily selectivity. For example, substrate-mimetic phosphonates have been used to target specific serine proteases and optimized peptide sequences can discriminate caspase isoforms. Binding or targeting motifs within the linker can further enhance interactions with enzymes whose active sites impose structural constraints, thereby improving probe specificity. In addition, linker length and composition can modulate probe permeability and distribution in cellular or in vivo contexts. This component allows probe designers to balance breadth (profiling an entire enzyme class) versus specificity (targeting individual members).
Korolev's conversion of his surplus Vostok capsules to the Voskhod spacecraft allowed the Soviet space program to beat the Gemini program in achieving the first spaceflight with a multi-person crew, and the first "spacewalk". Gemini took a year longer than planned to make its first flight, so Voskhod 1 became the first spaceflight with a three-person crew on October 12, 1964. The USSR touted another "technological achievement" during this mission: it was the first space flight during which cosmonauts performed in a shirt-sleeve-environment. However, flying without spacesuits was not due to safety improvements in the Soviet spacecraft's environmental systems; rather this was because the craft's limited cabin space did not allow for spacesuits. Flying without spacesuits exposed the cosmonauts to significant risk in the event of potentially fatal cabin depressurization. This was not repeated until the US Apollo Command Module flew in 1968; the command module cabin was designed to transport three astronauts in a low pressure, pure oxygen shirt-sleeve environment while in space. On March 18, 1965, about a week before the first piloted Project Gemini space flight, the USSR launched the two-cosmonaut Voskhod 2 mission with Pavel Belyayev and Alexei Leonov. Voskhod 2's design modifications included the addition of an inflatable airlock to allow for extravehicular activity (EVA), also known as a spacewalk, while keeping the cabin pressurized so that the capsule's electronics would not overheat. Leonov performed the first-ever EVA as part of the mission.
Sources: en.wikipedia.org
SR9009 is a synthetic research compound that binds and modulates the nuclear receptors REV-ERBα and REV-ERBβ. It is used in laboratory studies of circadian biology and metabolism, not as an approved medicine. It is also known by the informal name Stenabolic.
No. SR9009 has not been approved as a therapeutic drug in the United States, European Union, or other major markets. Human safety and efficacy data are very limited. Its presence in consumer products does not imply regulatory approval.
The World Anti-Doping Agency lists SR9009 as a prohibited substance because it can alter gene expression and metabolic pathways relevant to performance. The ban applies at all times, not only during competition. Detection relies on laboratory methods such as mass spectrometry.
Legality depends on the country and the intended use. In many places it is sold as a research chemical, but sports and medicine regulations restrict it.