HPLC-UV is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-03-16. Numbers and descriptions here follow the published literature rather than marketing material.
SR9009 is a synthetic small molecule studied as a REV-ERB agonist. REV-ERBα and REV-ERBβ are nuclear receptors that help regulate circadian rhythms and metabolic gene expression. The compound was identified in academic screening efforts to find synthetic ligands for these receptors. In cell and animal studies, SR9009 alters transcription of genes involved in lipid and glucose metabolism, and it can shift circadian behavior. It is not an approved therapeutic agent.
Mechanistically, SR9009 binds the ligand-binding domain of REV-ERBα/β and enhances recruitment of corepressor complexes. This represses target genes rather than activating them. Because REV-ERB proteins normally compete with ROR proteins at shared response elements, the net effect depends on tissue and timing. Researchers use SR9009 to probe how nuclear receptor signaling links the clock to metabolism, inflammation, and muscle biology. Findings are largely preclinical, and the precise contribution of each receptor subtype remains under study.
SR9009 is frequently discussed in fitness and research-chemical contexts, yet it has no approved medical indication. Regulatory agencies have not authorized it for human use, and it is not a standard prescription drug. Some sports organizations list it as a prohibited substance because of its potential performance-enhancing properties. Published human data are sparse, so claims about its effects in people often rely on animal models or anecdotal reports. Quality and identity of online materials can vary widely.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic REV-ERB agonist | Small-molecule ligand; not a hormone or peptide |
| Molecular formula | C20H24ClN3O4S | Reported for the free base |
| CAS Registry Number | 1379686-30-2 | Unique chemical identifier |
| Common synonyms | SR9009; stenabolic | Stenabolic is informal and not an official name |
| Reported targets | REV-ERBα and REV-ERBβ | Nuclear receptors linked to circadian and metabolic regulation |
Analytical identification of SR9009 typically relies on liquid chromatography coupled with tandem mass spectrometry. In biological samples, researchers first separate the compound from matrix components using protein precipitation, liquid-liquid extraction, or solid-phase extraction. High-performance liquid chromatography with ultraviolet detection and nuclear magnetic resonance spectroscopy can support structural confirmation of reference materials. Because SR9009 is a small, relatively lipophilic molecule, reverse-phase columns and acidic mobile phases are common. Laboratories often include isotope-labeled internal standards to improve quantification and to correct for ion suppression.
Stability depends on physical form, temperature, light exposure, and solvent. Solid SR9009 is generally stored cold and dry, with protection from light to limit degradation. Dimethyl sulfoxide stocks are common for laboratory work, but repeated freeze-thaw cycles can reduce compound integrity. Aqueous solutions may be less stable than organic stocks, and the ethyl ester in the structure can be susceptible to hydrolysis under certain conditions. Researchers typically validate storage conditions and recheck purity before quantitative experiments, especially when using archived material.
Regulatory treatment of SR9009 varies by country and region. It is not approved as a pharmaceutical, and several jurisdictions restrict its sale for human consumption. Some authorities classify it as a research chemical, a prescription-only substance, or a prohibited performance-enhancing agent in sport. Purchasers may encounter certificates of analysis, but these documents do not guarantee identity, purity, or legality. In research settings, institutional safety reviews and controlled procurement help ensure that materials are handled under appropriate oversight. The absence of harmonized rules means that legal status can change and requires verification.
Analytical chemists detect SR9009 with liquid chromatography-tandem mass spectrometry, commonly abbreviated LC-MS/MS. Sample preparation may involve protein precipitation, liquid-liquid extraction, or solid-phase extraction before analysis. Laboratories can target the parent compound or its metabolites, depending on the matrix and the purpose of testing. Anti-doping methods require sensitive and specific assays because concentrations in biological samples can be low. Reference standards and validated methods are essential for reliable identification and quantification.
Regulatory agencies have not approved SR9009 for human therapeutic use. It is typically sold as a research chemical with labels stating that it is not for human consumption. The World Anti-Doping Agency prohibits the substance in sport, generally under the category of non-approved substances. Customs and national laws may restrict importation, sale, or possession. Product quality and legal status can vary by country and vendor, and therapeutic claims are not permitted in regulated advertising because the compound lacks approval.
Several misconceptions surround SR9009. It is often described as a SARM, a steroid, or an exercise pill, but its known target is the REV-ERB receptor family. Rodent studies have examined exercise capacity and metabolic markers, yet human outcomes remain unproven. Oral bioavailability appears low in animals, and human pharmacokinetics are not well characterized. Online products may contain impurities or different compounds, so identity and purity testing are important for research use.
Handling practices for SR9009 focus on minimizing degradation and contamination. The solid is generally stored desiccated at or below -20 °C, protected from light and moisture. Stock solutions are often prepared in dimethyl sulfoxide or ethanol, then aliquoted to avoid repeated freeze–thaw cycles. Aqueous solubility is low, so formulations for animal studies may require cosolvents or suspending agents. Personnel should follow institutional chemical safety procedures, because toxicological data for humans are incomplete.
Regulatory status varies by country and intended use. Major drug agencies have not granted marketing authorization for SR9009 as a medicine, and it is not listed as a controlled substance in many jurisdictions. It is often sold as a research chemical, a category that may fall outside pharmaceutical manufacturing rules. Buyers should verify local laws and supplier documentation, including certificates of analysis. The lack of standardized quality controls raises concerns about identity, purity, and actual content in products marketed online.
After being forced to delay for several weeks at Bloemfontein by a shortage of supplies, an outbreak of typhoid at Paardeberg, and poor medical care, Roberts finally resumed his advance. He was forced to halt again at Kroonstad for 10 days, due once again to the collapse of his medical and supply systems, but captured Johannesburg on 31 May and the capital of the Transvaal, Pretoria, on 5 June. Before the war, the Boers had constructed forts south of Pretoria, but the artillery had been removed from the forts for use in the field, and in the event they abandoned Pretoria without a fight. Having won the principal cities, Roberts declared the war over on 3 September 1900; and the South African Republic was formally annexed.
=== Transforming growth factor β (TGF-β) === In normal conditions, alveolar macrophages adhere closely to alveolar epithelial cells, thus inducing the expression of the αvβ6 integrin. Integrins are dimeric cell-surface receptors composed of alpha and beta subunits, which activates TGF-β. TGF-β is a multifunctional cytokine that modulates a variety of biological processes such as cell growth, apoptosis, extracellular matrix synthesis, inflammation, and immune responses. TGF-β tightly regulates anti-inflammatory activity by suppressing pro-inflammatory cytokine production, thereby inhibiting T-lymphocyte function. Integrins avβ6 and avβ8 sequester latent TGF-β to the cell surface, where activation can be tightly coupled to cellular responses to environmental stress in the maintenance of homeostasis; integrins also localize activated TGFβ in the vicinity of the macrophages. Normally mature TGFβ is secreted as a latent complex with its N-terminal fragment, latency-associated peptide (LAP), which inhibits its activity. The latent complex is covalently linked to the extracellular matrix by binding to latent TGF-β-binding proteins. TGF-β is activated by diverse mechanisms in the lung, ultimately involving either proteolysis or conformational alteration of the LAP. αvβ6 integrin is able to mediate activation of TGF-β by binding to TGF-β1 LAP, which serves as a ligand binding site for the integrin, and is an essential component of the TGF-β activation apparatus. Once activated, TGFβ leads to the suppression of macrophage functionality (cytokine production and phagocytosis).
=== Light scattering === Static light scattering measures the product of weight-averaged molar mass and concentration of macromolecules in solution. Given a fixed total concentration of one or more species over the measurement time, the scattering signal is a direct measure of the weight-averaged molar mass of the solution, which will vary as complexes form or dissociate. Hence the measurement quantifies the stoichiometry of the complexes as well as kinetics. Light scattering assays of protein kinetics is a very general technique that does not require an enzyme.
== Adverse effects == The US Food and Drug Administration (FDA) prescribing information for taletrectinib includes warnings and precautions for hepatotoxicity, interstitial lung disease/pneumonitis, QTc interval prolongation, hyperuricemia, myalgia with creatine phosphokinase elevation, skeletal fractures, and embryo-fetal toxicity.
Sources: en.wikipedia.org
Although these patients were historically classified as having DM, they are now generally considered to have the distinct clinical entity antisynthetase syndrome, even in the presence of characteristic cutaneous features. Magnetic resonance imaging may be useful for guiding muscle biopsy and for distinguishing active inflammation from irreversible muscle damage as contributors to muscle weakness. In addition to muscle inflammation, MRI frequently demonstrates fascial inflammation (fasciitis) in patients with DM. X-ray may be used to investigate joint involvement and calcifications. A case of DM may be classified as clinically amyopathic dermatomyositis (CADM) when cutaneous manifestations predominate and there is little or no clinical evidence of muscle involvement. Anti-MDA5 autoantibodies are strongly associated with CADM and are frequently accompanied by rapidly progressive interstitial lung disease. Patients with anti-TIF1-γ autoantibodies also commonly present with clinically amyopathic disease, although less frequently than those with anti-MDA5 autoantibodies. Juvenile dermatomyositis (JDM) has traditionally been regarded as a distinct entity from adult-onset DM. However, there is no convincing evidence that the two differ fundamentally in their pathophysiology, and they are now generally considered age-specific presentations of the same group of conditions.
Serum albumins are the most common plasma proteins, and they are responsible for maintaining the osmotic pressure of the blood. Without albumins, the consistency of blood would be closer to that of water. The increased viscosity of blood prevents fluid from entering the bloodstream from outside the capillaries. Albumins are produced in the liver, assuming the absence of a hepatocellular deficiency.
In 1884, Svante Arrhenius attributed the properties of acidity to hydrogen cations (H+), later described as protons or hydrons. An Arrhenius acid is a substance that, when added to water, increases the concentration of H+ ions in the water. Chemists often write H+(aq) and refer to the hydrogen cation when describing acid–base reactions but the free hydrogen nucleus, a proton, does not exist alone in water, it exists as the hydronium ion (H3O+) or other forms (H5O2+, H9O4+). Thus, an Arrhenius acid can also be described as a substance that increases the concentration of hydronium ions when added to water. Examples include molecular substances such as hydrogen chloride and acetic acid. An Arrhenius base, on the other hand, is a substance that increases the concentration of hydroxide (OH−) ions when dissolved in water. This decreases the concentration of hydronium because the ions react to form H2O molecules:
Sources: en.wikipedia.org
SR9009 is a synthetic compound investigated as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is used in preclinical research on circadian rhythm and metabolism. It is not an approved drug.
No. It has no approved medical indication, and human safety and efficacy data are limited. It appears in research chemical markets and is banned by some sports authorities.
Natural ligands include heme and certain metabolites; SR9009 is a synthetic small molecule with higher potency and selectivity in some assays. Its effects depend on cell type and timing. It is not a naturally occurring compound.
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.