If you have been reading about anti-doping testing and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-10-30. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
Storage recommendations for SR9009 reference material typically specify a freezer at -20 °C or lower, with protection from moisture and light. Repeated freeze-thaw cycles can degrade small molecules and introduce variability. Stock solutions in dimethyl sulfoxide are often aliquoted to avoid repeated handling. Stability studies may examine degradation under heat, humidity, and light exposure. The compound's thiophene and nitro groups can participate in reactions that alter analytical signals over time, so such changes affect quantitative results.
Quality control for research materials includes identity confirmation by nuclear magnetic resonance and purity assessment by high-performance liquid chromatography. Mass spectrometry provides molecular weight confirmation and can detect related impurities. Purchasers should request a certificate of analysis that lists lot-specific data. Online products advertised for human use often lack such documentation. Distinguishing legitimate research material from mislabeled or contaminated samples is a recurring challenge in independent testing, and independent laboratories may use orthogonal methods to verify identity.
Detection of SR9009 in biological samples usually relies on liquid chromatography coupled to tandem mass spectrometry. This approach separates the compound from matrix components and identifies it by mass transitions. Because SR9009 can undergo metabolism, laboratories often look for both parent drug and specific metabolites. Sample preparation may involve protein precipitation or solid-phase extraction. Method validation examines sensitivity, carryover, and interference from related substances, and reference standards are required for accurate calibration.
| 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 |
Scientific discussion of SR9009 often separates animal evidence from human anecdote. Rodent studies provide controlled data on endurance, metabolism, and gene expression, but they use specific strains, doses, and treatment durations. Human reports are mostly uncontrolled and cannot establish cause and effect. Open questions include oral bioavailability, tissue distribution, metabolic stability, and long-term effects. Review articles generally call for more rigorous pharmacokinetic and safety research before any clinical use could be considered.
Analytical methods for SR9009 typically rely on liquid chromatography coupled with tandem mass spectrometry. The technique can separate the parent compound from related substances and detect low concentrations in biological matrices. Urine and blood are common samples in anti-doping testing, while in vitro studies may use cell culture media. Rapid metabolism and low expected concentrations make method validation important for reliable identification. Exact metabolite patterns can vary by species and are not fully mapped.
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.
Pharmacokinetic data for SR9009 are limited in published literature. Some reports indicate low oral bioavailability and rapid clearance in animals, which complicates interpretation of exposure and effect. Researchers often use injected routes in preclinical work to achieve measurable systemic levels. Analytical studies rely on mass spectrometry to detect the parent compound and its metabolites. Questions about tissue distribution, active metabolites, and long-term consequences remain open. Species differences in metabolism can affect observed half-life and target engagement.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. These receptors help regulate circadian rhythms and metabolic gene expression. In laboratory experiments, SR9009 binds these receptors and alters transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. It is not a naturally occurring compound and has no approved therapeutic use. Research interest stems from its ability to modify energy metabolism in cells and animal models.
Preclinical reports have linked SR9009 to improved endurance and altered energy expenditure in rodents. Such findings have prompted interest in whether REV-ERB activation can influence skeletal muscle metabolism. However, the reported effects depend on dose, route, and experimental model, and replication across laboratories is limited. Human trials have not established comparable outcomes, so claims about exercise performance remain speculative. The absence of controlled human data is a central limitation in interpreting these observations.
The mechanism of action involves binding to REV-ERB receptors and recruiting corepressor complexes, which represses target gene transcription. This contrasts with many nuclear receptor agonists that activate transcription. Downstream effects may include changes in autophagy, mitochondrial biogenesis, and lipid handling, but the precise pathways remain an active area of study. Whether these molecular events translate into meaningful physiological effects in humans is unresolved. Most evidence comes from cultured cells and rodent models rather than human participants.
Ibogaine biosynthesis begins with tryptophan undergoing enzymatic decarboxylation by tryptophan decarboxylase (TDC) to form tryptamine. Secologanin, an iridoid synthesized from isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), is reacted with tryptamine to make strictosidine. A glycosidic bond cleavage of strictosidine by strictosidine β-deglucosidase (SGD) produces a lactol. The lactol opens and produces an aldehyde, then condenses to form an iminium. Through isomerization and reduction by geissoschizine synthase 1 (GS1), 19E-geissoschizine is yielded. The indole is oxidized, and the molecule undergoes an intramolecular Mannich reaction and Grob fragmentation to form preakuammicine. Preakuammicine is highly unstable and therefore reduced to stemmadenine by oxidation-reduction reactions (REDOX 1 and REDOX 2). Stemmadine is acylated by stemmadine Ο-acetyltransferase (SAT) to yield stemmadine acetate. Through oxidation by precondylocarpine acetate synthase (PAS) and reduction by dihydroprecondylocarpine acetate synthase (DPAS), an enamine intermediate is formed. The intermediate undergoes fragmentation to produce an iminium that tautomerizes to yield dehydrosecodine. Coronaridine synthase (CorS) catalyzes the isomerization of dehydrosecodine, and an unusual cycloaddition is completed. DPAS and NADPH reduce the iminium to form (-)-coronaridine. There are two pathways (-)-coronaridine can take to become (-)-ibogaine.
Overview of all the structural information available in the PDB for UniProt: P0DPI1 (Botulinum neurotoxin type A) at the PDBe-KB. Overview of all the structural information available in the PDB for UniProt: P10844 (Botulinum neurotoxin type B) at the PDBe-KB. Overview of all the structural information available in the PDB for UniProt: A0A0X1KH89 (Bontoxilysin A) at the PDBe-KB. "AbobotulinumtoxinA Injection". MedlinePlus. "IncobotulinumtoxinA Injection". MedlinePlus. "OnabotulinumtoxinA Injection". MedlinePlus. "PrabotulinumtoxinA-xvfs Injection". MedlinePlus. "RimabotulinumtoxinB Injection". MedlinePlus.
A 2021 deep-learning algorithms-based software called AlphaFold, developed by Google's DeepMind, released predicted structures for hundreds of millions of proteins in the AlphaFold protein structure database.
=== Return to Prague === In November 1945, Smolková-Keulemansová returned to Prague to continue her studies. She completed grammar school and realized that the biggest struggle in her supplementary exams was chemistry, so she began to study chemistry at Charles University in Prague, leading to her lifelong devotion and love for the subject. She graduated from the Faculty of Natural Sciences at Charles University in 1952.
Sources: en.wikipedia.org
==== Role in atmospheric chemistry ==== As a short-lived but very reactive carbonyl compound, HCHO is important in the oxidation chemistry of the troposphere. It is a key source of odd-hydrogen radicals (HOx = OH + HO2) that help to sustain the atmosphere's oxidative capacity. It is also an important ozone precursor. HCHO removal in the troposphere occurs primarily via photodissociation, through two main pathways: molecular and radical-forming channels, the threshold wavelengths for which are given in parentheses:
Soybeans with black hulls are used in Chinese fermented black beans, douchi, not to be confused with black turtle beans. Soybeans are also used in industrial products, including oils, soap, cosmetics, resins, plastics, inks, crayons, solvents, and clothing. Soybean oil is the primary source of biodiesel in the United States, accounting for 80% of domestic biodiesel production. Soybeans have also been used since 2001 as fermenting stock in the manufacture of a brand of vodka. In 1936, Ford Motor Company developed a method where soybeans and fibers were rolled together producing a soup which was then pressed into various parts for their cars, from the distributor cap to knobs on the dashboard. Ford also informed in public relation releases that in 1935 over five million acres (20,000 km2) was dedicated to growing soybeans in the United States.
chemical decomposition The breakdown of a single particle or entity (such as a molecule or reactive intermediate) into two or more fragments, or a chemical reaction in which two or more products are formed from a single reactant. Contrast chemical synthesis.
==== Officer of the Order of the British Empire (OBE) ==== Civil Joseph Martin Chow Sun Yau, . For services to the Business and to the Community. Abdul Wahed Mohammed. For services to Education, to Business Development and to the communities in the National Capital District and Central Provinces during Covid-19. Chan Wing Onn. For services to Business and to the Community.
*No known examples The smallest unit forming a homo-oligomer, i.e. one protein chain or subunit, is designated as a monomer, subunit or protomer. The latter term was originally devised to specify the smallest unit of hetero-oligomeric proteins, but is also applied to homo-oligomeric proteins in current literature. The subunits usually arrange in cyclic symmetry to form closed point group symmetries. Although complexes higher than octamers are rarely observed for most proteins, there are some important exceptions. Viral capsids are often composed of multiples of 60 proteins. Several molecular machines are also found in the cell, such as the proteasome (four heptameric rings = 28 subunits), the transcription complex and the spliceosome. The ribosome is probably the largest molecular machine, and is composed of many RNA and protein molecules. In some cases, proteins form complexes that then assemble into even larger complexes. In such cases, one uses the nomenclature, e.g., "dimer of dimers" or "trimer of dimers". This may suggest that the complex might dissociate into smaller sub-complexes before dissociating into monomers. This usually implies that the complex consists of different oligomerisation interfaces. For example, a tetrameric protein may have one four-fold rotation axis, i.e. point group symmetry 4 or C4. In this case the four interfaces between the subunits are identical. It may also have point group symmetry 222 or D2. This tetramer has different interfaces and the tetramer can dissociate into two identical homodimers.
Sources: en.wikipedia.org
== Deterministic versus stochastic epidemic models == The deterministic models presented here are valid only in case of sufficiently large populations, and as such should be used cautiously. These models are only valid in the thermodynamic limit, where the population is effectively infinite. In stochastic models, the long-time endemic equilibrium derived above, does not hold, as there is a finite probability that the number of infected individuals drops below one in a system. In a true system then, the pathogen may not propagate, as no host will be infected. But, in deterministic mean-field models, the number of infected can take on real, namely, non-integer values of infected hosts, and the number of hosts in the model can be less than one, but more than zero, thereby allowing the pathogen in the model to propagate. The reliability of compartmental models is limited to compartmental applications. One of the possible extensions of mean-field models considers the spreading of epidemics on a network based on percolation theory concepts. Stochastic epidemic models have been studied on different networks and more recently applied to the COVID-19 pandemic.
Sudomotor function refers to the autonomic nervous system control of sweat gland activity in response to various environmental and individual factors. Sweat production is a vital thermoregulatory mechanism used by the body to prevent heat-related illness as the evaporation of sweat is the body's most effective method of heat reduction and the only cooling method available when the air temperature rises above skin temperature. In addition, sweat plays key roles in grip, microbial defense, and wound healing.
=== Web advertising === In November 2018, the 23 original Kwentong Jollibee videos on its YouTube channel reached a total of 64 million views. After nearly two years the total views had risen to 405 million, with 567,000 subscribers, in July 2020.
The state is dominated by several large northwards-flowing rivers, including the Ems, Weser, Aller, and the Elbe. The highest point in Lower Saxony is the Wurmberg (971 metres or 3,186 feet) in the Harz. Most of the significant hills and mountains are found in the southeastern part of the state. The lowest point in the state, at about 2.5 metres or 8 feet 2 inches below sea level, is a depression near Freepsum in East Frisia. The state's economy, population, and infrastructure are centred on the cities and towns of Hanover, Stadthagen, Celle, Braunschweig, Wolfsburg, Hildesheim, and Salzgitter. Together with Göttingen in southern Lower Saxony, they form the core of the Hannover–Braunschweig–Göttingen–Wolfsburg Metropolitan Region.
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.
Liquid chromatography-tandem mass spectrometry is a common approach. It can detect the parent compound and its metabolites in biological matrices.