If you have been reading about LC-MS/MS 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 2026-07-30. 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.
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.
| 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 |
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.
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.
A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical trial. (NCI) A clinical trial is a research study to answer specific questions about vaccines or new therapies or new ways of using known treatments. Clinical trials (also called medical research and research studies) are used to determine whether new drugs or treatments are both safe and effective. Carefully conducted clinical trials are the fastest and safest way to find treatments that work in people. Trials are in four phases: Phase I tests a new drug or treatment in a small group; Phase II expands the study to a larger group of people; Phase III expands the study to an even larger group of people; and Phase IV takes place after the drug or treatment has been licensed and marketed. (NLM) Any investigation in human subjects intended to discover or verify the clinical, pharmacological, and/or other pharmacodynamic effects of an investigational product(s), and/or to identify any adverse reactions to an investigational product(s), and/or to study absorption, distribution, metabolism, and excretion of an investigational product(s) with the object of ascertaining its safety and/or efficacy. The terms clinical trial and clinical study are synonymous. (ICH E6) Clinical Trial/Study Report
Factor VIII was first characterized in 1984 by scientists at Genentech. The gene for factor VIII is located on the X chromosome (Xq28). The gene for factor VIII presents an interesting primary structure, as another gene (F8A1) is embedded in one of its introns.
Ion exchange is a reversible interchange of one species of ion present in an insoluble solid with another of like charge present in a solution surrounding the solid. Ion exchange is used in softening or demineralizing of water, purification of chemicals, and separation of substances. Ion exchange usually describes a process of purification of aqueous solutions using solid polymeric ion-exchange resin. More precisely, the term encompasses a large variety of processes where ions are exchanged between two electrolytes. Aside from its use to purify drinking water, the technique is widely applied for purification and separation of a variety of industrially and medicinally important chemicals. Although the term usually refers to applications of synthetic (human-made) resins, it can include many other materials such as soil. Typical ion exchangers are ion-exchange resins (functionalized porous or gel polymer), zeolites, montmorillonite, clay, and soil humus. Ion exchangers are either cation exchangers, which exchange positively charged ions (cations), or anion exchangers, which exchange negatively charged ions (anions). There are also amphoteric exchangers that are able to exchange both cations and anions simultaneously. However, the simultaneous exchange of cations and anions is often performed in mixed beds, which contain a mixture of anion- and cation-exchange resins, or passing the solution through several different ion-exchange materials.
Teacher of Mathematics, Grange Academy, Kilmarnock. For services to Mathematics Education and to the community in East Ayrshire. Professor Matthew David Snape. Lately Professor in Paediatrics and Vaccinology, Oxford Vaccine Group, University of Oxford. For services to Public Health, particularly during Covid-19. Ellen Somme. Founder, Teddy Trust. For services to Vulnerable Children. Keith Wyn Sorrell. Lately Chief Executive Officer, Windsor Academy Trust. For services to Education. Stephen Terence Sorrell. Director, Small Things Creative Projects Community Interest Company. For services to Arts and Culture in Greater Manchester. Julie Spencer. Head of Student Wellbeing Service, University of Lincoln. For services to Education. Karen Eleanor Spiers. Senior Charge Nurse, NHS Lanarkshire. For services to Dementia Care in Hospital. Robert Jeffrey Stelling. Lately Broadcaster, Sky Sports. For services to Sport, to Broadcasting and to Charity. Richard Alexander Stewart. Lately Trustee and Chair of Trustees, St. John's School and College. For services to Children and Young People with Special Educational Needs and Disabilities. Amanda St John Davey. National Chair, Women in Property. For services to Working Women. Dr. Andrew Stott. Lately Science Adviser, Department for Environment, Food and Rural Affairs. For services to Nature and Climate. Professor Peter Alister Stott. Deputy Head of Climate Science and Science Fellow, Met Office. For services to Climate Science. The Reverend Professor Elizabeth Bridget Stuart. Lately Deputy Vice-Chancellor, University of Winchester.
Sources: en.wikipedia.org
The use of N-terminal Fmoc deprotection scheme is truly orthogonal under SPPS conditions. Fmoc deprotection is a base-catalyzed elimination reaction that typically uses 20–50% piperidine in DMF. The revealed alpha-amine functionality is therefore neutral, and consequently no neutralization of the peptide-resin is required, as in the case of the Boc/Bzl approach. The lack of electrostatic repulsion between the peptide chains can lead to increased risk of aggregation with Fmoc/tBu SPPS however. Because the liberated fluorenyl group is a chromophore, Fmoc deprotection can be monitored by UV absorbance of the reaction mixture, a strategy which is employed in automated peptide synthesizers. The ability of the Fmoc group to be cleaved under relatively mild basic conditions while being stable to acid allows the use of side chain protecting groups such as Boc and tBu that can be removed in milder acidic final cleavage conditions (TFA) than those used for final cleavage in Boc/Bzl SPPS (HF). Scavengers such as water and triisopropylsilane (TIPS) are most commonly added during the final cleavage in order to prevent side reactions with reactive cationic species released as a result of side chain deprotection. Nevertheless, many other scavenger compounds could be used as well. The resulting crude peptide is obtained as a TFA salt, which is potentially more difficult to solubilize than the fluoride salts generated in Boc SPPS. Fmoc/tBu SPPS is less atom-economical, as the fluorenyl group has a much higher mass than the Boc group.
==== In adults ==== In 2022, the UK National Institute for Health and Care Excellence (NICE) recommended that antidepressants be offered as a first-line treatment for moderate to severe depression, but for mild depression, non-drug interventions are preferred unless the patient chooses medication. They recommended that antidepressants should not be routinely offered for mild depression and should generally be used only if non-drug treatments fail or the patient prefers medication. In a 2018 review, all 21 studied antidepressants were more effective than placebo for major depressive disorder. The commonly used definition of antidepressant "response" as a 50% symptom reduction dichotomizes continuous data, which methodologists note can inflate effect sizes, exaggerate drug–placebo differences, and may not reliably indicate clinical significance. A large FDA trial analysis found that SSRIs and other antidepressants produced only modest average benefits over placebo, with about 15% of patients experiencing a substantial drug-specific response. SSRIs and other antidepressants may have average treatment effects that fall below the minimal important difference on common depression outcome measures, leaving their clinical significance in acute moderate-to-severe depression uncertain. There is no consistent evidence that depression is caused by lowered serotonin activity or concentrations, with some data suggesting that long-term antidepressant use may reduce serotonin levels.
Rubella, also known as German measles, was also very common before widespread vaccination. The major risk of rubella is during pregnancy when the baby may contract congenital rubella, which can cause significant congenital defects.
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.
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.