This is a working overview of LC-MS/MS, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-02-03 and is reviewed periodically as new material appears.
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.
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.
| 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 |
Handling recommendations for SR9009 in a laboratory setting include storing the solid at low temperature, protected from light and moisture. The compound is often dissolved in dimethyl sulfoxide or ethanol for experiments. Solutions should be prepared with appropriate personal protective equipment and disposed of according to local rules. Stability data for long-term storage are limited, so stock solutions are typically kept cold and used within defined periods. Records of preparation date and concentration support reproducibility.
SR9009 is not approved as a medicine by major regulatory agencies. It is commonly sold as a research chemical, a category that may fall outside customary drug approval and quality rules. In sports, the World Anti-Doping Agency lists SR9009 as a prohibited substance. Athletes who use it can face sanctions if it is detected in a sample. Legal status varies by country, and importation may be restricted. Enforcement practices differ across borders.
Detection of SR9009 in biological samples usually employs liquid chromatography coupled with tandem mass spectrometry. This method can identify the parent compound and sometimes metabolites in urine or blood. Because exposure can be low and clearance may be rapid, sample timing and limits of detection matter. Laboratories validate assays for sensitivity and specificity. Results are interpreted alongside chain-of-custody and quality-control records. Urine is the common matrix for anti-doping analysis, while blood may be used in research settings.
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.
== Bone versus cartilage == The primitive skeleton is cartilage, a solid avascular (without blood vessels) tissue in which individual cartilage-matrix secreting cells, or chondrocytes, occur. Chondrocytes do not have intercellular connections and are not coordinated in units. Cartilage is composed of a network of collagen type II held in tension by water-absorbing proteins, hydrophilic proteoglycans. This is the adult skeleton in cartilaginous fishes such as sharks. It develops as the initial skeleton in more advanced classes of animals. In air-breathing vertebrates, cartilage is replaced by cellular bone. A transitional tissue is mineralized cartilage. Cartilage mineralizes by massive expression of phosphate-producing enzymes, which cause high local concentrations of calcium and phosphate that precipitate. This mineralized cartilage is not dense or strong. In the air breathing vertebrates it is used as a scaffold for formation of cellular bone made by osteoblasts, and then it is removed by osteoclasts, which specialize in degrading mineralized tissue. Osteoblasts produce an advanced type of bone matrix consisting of dense, irregular crystals of hydroxyapatite, packed around the collagen ropes. This is a strong composite material that allows the skeleton to be shaped mainly as hollow tubes. Reducing the long bones to tubes reduces weight while maintaining strength.
== Medical uses == Azapirones have shown benefit in general anxiety and augmenting SSRIs in social anxiety and depression. Evidence is not clear for panic disorder and functional gastrointestinal disorders. Tandospirone has also been used to augment antipsychotics in Japan as it improves cognitive and negative symptoms of schizophrenia. Buspirone is being investigated for this purpose as well.
== Pharmacology == AM-2201 is a full agonist for cannabinoid receptors. Affinities are: with a Ki of 1.0 nM at CB1 and 2.6 nM at CB2. The 4-methyl functional analog MAM-2201 probably has similar affinities. AM-2201 has an EC50 of 38 nM for human CB1 receptors, and 58 nM for human CB2 receptors. AM-2201 produces bradycardia and hypothermia in rats at doses of 0.3–3 mg/kg, comparable to the potency of JWH-018 in rats, suggesting potent cannabinoid-like activity.
==== 2023 Rugby World Cup ==== 9 September – Ireland 82–8 Romania, Nouveau Stade de Bordeaux, Bordeaux. 16 September – Ireland 59–16 Tonga, Stade de la Beaujoire, Nantes. 23 September – South Africa 8–13 Ireland, Stade de France, Saint-Denis. 7 October – Ireland 36–14 Scotland, Saint-Denis. 14 October – Ireland 24–28 New Zealand. Ireland were eliminated by New Zealand in the quarter final.
Sources: en.wikipedia.org
CHAPS is a zwitterionic surfactant used in the laboratory to solubilize biological macromolecules such as proteins. It may be synthesized from cholic acid and is zwitterionic due to its quaternary ammonium and sulfonate groups; it is structurally similar to certain bile acids, such as taurodeoxycholic acid and taurochenodeoxycholic acid. It is used as a non-denaturing detergent in the process of protein purification and is especially useful in purifying membrane proteins, which are often sparingly soluble or insoluble in aqueous solution due to their native hydrophobicity. CHAPS is an abbreviation for 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate. A related detergent, called CHAPSO, has the same basic chemical structure with an additional hydroxyl functional group; its full chemical name is 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propanesulfonate. Both detergents have low light absorbance in the ultraviolet region of the electromagnetic spectrum, which is useful for monitoring ongoing chemical reactions or protein-protein binding with UV/Vis spectroscopy.
The pipes being used by the nearby workers were only 1⁄2 inch (13 mm) in diameter and were physically incapable of producing enough hydraulic pressure to raise the water more than 10 feet (3.0 m) that would have been necessary to enable the water to "backflow" into the MIC tank. A key intermediate valve would have had to be open for the Negligence argument to apply. This valve was "tagged" closed, meaning that it had been inspected and found to be closed. While it is possible for open valves to clog over time, the only way a closed valve allows penetration is if there is leakage, and 1985 tests carried out by the government of India found this valve to be non-leaking. In order for water to have reached the MIC tank from the pipe-cleaning area, it would have had to flow through a significant network of pipes ranging from 6 to 8 inches (150 to 200 mm) in diameter, before rising 3.0 metres (10 ft) and flowing into the MIC tank. Had this occurred, most of the water that was in those pipes at the time the tank had its critical reaction would have remained in those pipes, as there was no drain for them. Investigation by the Indian government in 1985 revealed that the pipes were bone dry.
While this terminology results in a simplified way of dealing with kinetic effects relating to the maximum velocity of the Michaelis–Menten equation, it highlights potential problems with the term used to describe effects relating to the KM. The KM relating to the affinity of the enzyme for the substrate should in most cases relate to potential changes in the binding site of the enzyme which would directly result from enzyme inhibitor interactions. As such, a term similar to the one proposed above to modulate Vmax should be appropriate in most situations:
== Chromatography == One of the main reasons to use response factors is to compensate for the irreproducibility of manual injections into a gas chromatograph (GC). Injection volumes for GCs can be 1 microliter (μL) or less and are difficult to reproduce. Differences in the volume of injected analyte leads to differences in the areas of the peaks in the chromatogram and any quantitative results are suspect. To compensate for this error, a known amount of an internal standard (a second compound that does not interfere with the analysis of the primary analyte) is added to all solutions (standards and unknowns). This way if the injection volumes (and hence the peak areas) differ slightly, the ratio of the areas of the analyte and the internal standard will remain constant from one run to the next. This comparison of runs also applies to solutions with different concentrations of the analyte. The area of the internal standard becomes the value to which all other areas are referenced. Below is the mathematical derivation and application of this method. Consider an analysis of octane (C8H18) using nonane (C9H20) as the internal standard. The 3 chromatograms below are for 3 different samples.
=== Global perspective === Historically, mental health challenges were criticized, underprioritized, and limited to the public due to lack of recognition. However, recent developments evolved over time to include quality care settings and accessible resources for individuals needing mental health support. Interventions reduced treatment gaps by catering to many diverse cultures and implementing health services across the globe. International organizations, such as the World Health Organization, increased funding towards mental health services that specialize in disorders.
Sources: en.wikipedia.org
== Applications == In the synthesis of aspartame, less bitter-tasting byproduct is produced when the reaction is catalyzed by thermolysin. Determining protein stability in cell lysate using the fast parallel proteolysis (FASTpp) assay.
The Appalachian belt includes the plateaus sloping southward to the Atlantic Ocean in New England, and southeastward to the border of the coastal plain through the central and southern Atlantic states; and on the northwest, the Allegheny and Cumberland plateaus declining toward the Great Lakes and the interior plains. A remarkable feature of the belt is the longitudinal chain of broad valleys, including the Great Appalachian Valley, which in the southerly sections divides the mountain system into two unequal portions, but in the northernmost lies west of all the ranges possessing typical Appalachian features, and separates them from the Adirondack group. The mountain system has no axis of dominating altitudes, but in every portion, the summits rise to rather uniform heights, and, especially in the central section, the various ridges and intermontane valleys have the same trend as the system itself. None of the summits reaches the region of perpetual snow. In Pennsylvania, there are over sixty summits that rise over 2,500 ft (800 m); the summits of Mount Davis and Blue Knob rise over 3,000 ft (900 m). In Maryland, Eagle Rock and Dans Mountain are conspicuous points reaching 3,162 and 2,882 ft (964 and 878 m) respectively. On the same side of the Great Valley, south of the Potomac, are the Pinnacle 3,007 feet (917 m) and Pigeon Roost 3,400 ft (1,000 m). In West Virginia, more than 150 peaks rise above 4,000 ft (1,200 m), including Spruce Knob 4,863 ft (1,482 m), the highest point in the Allegheny Mountains. A number of other points in the state rise above 4,800 ft (1,500 m).
== Pathophysiology == Copper functions as a prosthetic group, permitting electron transfers in key enzymatic pathways like the electron transport chain. Copper is integrated in the enzymes cytochrome c oxidase, which is involved in cellular respiration and oxidative phosphorylation, Cu/Zn dismutase, which is involved in antioxidant defense, and many more listed in the table below.
16 February – Former footballer Ciaran Dickson is sentenced to six years in prison by the High Court in Glasgow for the hit-and-run killing of Aidan Pilkington in September 2021, when he was more than three times over the drink drive limit. Scotland is to scrap its Super 6 rugby series and reinstate a national "A team" as part of a comprehensive restructuring programme. 17 February – Delegates at the Scottish Labour Party conference pass a resolution calling for an immediate ceasefire in Gaza. Two men are killed in a road traffic accident involving three cars on the B9077 in Maryculter, Aberdeenshire. 20 February – Heather Woodbridge, aged 29, is appointed as leader of Orkney Islands Council, becoming Scotland's youngest council leader and the first woman to lead Orkney Islands Council. The BBC announces plans to reshape the BBC Scotland TV channel, including axing the hour-long news programme The Nine and replacing it with a 30-minute programme. 22 February – Argyll and Bute Council votes to raise its council tax by 10%, and rejects the Scottish Government's council tax freeze by doing so. 23 February – The Scottish Government publishes draft legislation proposing a ban on the sale of disposable vapes in Scotland by 1 April 2025. 24 February – Police Scotland begins an investigation after burnt human remains are found near Motherwell Football Club. 25 February – The Scottish Government confirms that Economy Secretary Màiri McAllan, who is pregnant, will take maternity leave during the summer, becoming the second Scottish Government minister to do so.
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.
Laboratories commonly use liquid chromatography coupled with mass spectrometry to detect SR9009. The method can identify the compound and estimate concentration in a sample. Detection limits depend on the matrix and instrument.