Everything below concerns research chemical. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-10-12. Where a claim depends on a specific study, the study is described rather than over-claimed.
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 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.
Research interest in SR9009 grew from studies showing improved running endurance in mice after short treatment periods. Those experiments linked the compound to increased mitochondrial content and fatty acid oxidation in muscle, but the findings come from animal models and specific dosing schedules. Independent replication has been limited, and the pathways connecting REV-ERB activation to exercise performance are still being mapped. Whether similar responses occur in humans is an open question.
SR9009 is often grouped with compounds studied for circadian and metabolic regulation rather than with classical anabolic steroids. Its interactions with nuclear receptors differ from those of androgen receptor ligands, and its proposed mechanisms involve transcriptional control rather than direct hormone signaling. Some sources classify it as a metabolic modulator because of observed effects on energy utilization. The distinction matters for regulation and for interpreting research results across different compound classes.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | SR9009; Stenabolic | Nickname is not a chemical name. |
| Typical analytical method | LC-MS/MS | Often with isotope-labeled internal standard. |
| Storage temperature | -20 °C | Desiccated and protected from light. |
| Solution stability | DMSO stock; avoid freeze-thaw | Store at -20 to -80 °C. |
| Regulatory status | Not approved; varies by country | May be restricted as research chemical. |
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is not an approved medicine and has no established human therapeutic use. The compound appears in scientific literature as a tool for probing circadian and metabolic regulation. Online sellers often label it as a research chemical, sometimes using the nickname Stenabolic. Its chemical identity is distinct from selective androgen receptor modulators, stimulants, and peroxisome proliferator-activated receptor delta agonists. Researchers use it mainly in cell and animal experiments.
At the molecular level, SR9009 binds REV-ERBα and REV-ERBβ and alters their repressive activity on target genes. These nuclear receptors help regulate the circadian clock, lipid synthesis, glucose metabolism, and inflammatory pathways. By changing transcription, the compound can shift the timing or magnitude of downstream metabolic processes in model systems. It does not act through androgen receptors or adenosine receptors, which distinguishes it from several substances sold for athletic performance. Whether the same transcriptional changes occur in humans at tolerable exposures remains an open question because controlled human studies are lacking.
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.
In laboratory settings, SR9009 is commonly identified by its molecular structure and its interaction with REV-ERB receptors. Vendors may list it under synonyms such as Stenabolic or REV-ERB agonist, but those names do not define purity or identity. Analytical confirmation typically uses high-performance liquid chromatography with ultraviolet detection or liquid chromatography–mass spectrometry. A reference standard is needed to compare retention time and mass spectrum, because the compound can be confused with related research chemicals.
Aqueous normal-phase (ANP) chromatography is characterized by the elution behavior of classical normal phase mode (i.e. where the mobile phase is significantly less polar than the stationary phase) in which water is one of the mobile phase solvent system components. It is distinguished from hydrophilic interaction liquid chromatography (HILIC) in that the retention mechanism is due to adsorption rather than partitioning.
== In protein dynamics == The significance of peptide plane flips in the dynamics of the native state has been inferred in some proteins by comparing crystal structures of the same protein in multiple conformations. For example, peptide flips have been described as significant in the catalytic cycle of flavodoxin and in the formation of amyloid structures, where their ability to provide a low-energy pathway between beta sheet and the so-called alpha sheet conformation is suggested to facilitate the early stages of amyloidogenesis. Peptide plane flipping may also be significant in the early stages of protein folding.
==== United States ==== TMA-2 is not an explicitly controlled substance in the United States. However, it is a positional isomer of 3,4,5-trimethoxyamphetamine (TMA), and thus may be considered a Schedule I controlled substance in this country similarly to TMA.
== Complications == The denaturing of proteins by an aqueous solution containing many types of ions is more complicated as all the ions can act, according to their Hofmeister activity, i.e., a fractional number specifying the position of the ion in the series (given previously) in terms of its relative efficiency in denaturing a reference protein. At high salt concentrations lysozyme protein aggregation obeys the Hofmeister series originally observed by Hofmeister in the 1870s, but at low salt concentrations electrostatic interactions rather than ion dispersion forces affect protein stability resulting in the series being reversed. However, at high concentrations of salt, the solubility of the proteins drops sharply and proteins can precipitate out. Ion binding to carboxylic surface groups of macromolecules can either follow the Hofmeister series or the reversed Hofmeister series depending on the pH. The concept of Hofmeister ionicity Ih has been invoked by Dharma-wardana et al. where it is proposed to define Ih as a sum over all ionic species, of the product of the ionic concentration (mole fraction) and a fractional number specifying the "Hofmeister strength" of the ion in denaturing a given reference protein. The concept of ionicity (as a measure of the Hofmeister strength) used here has to be distinguished from ionic strength as used in electrochemistry, and also from its use in the theory of solid semiconductors.
Sources: en.wikipedia.org
The standard enthalpy change can be determined by calorimetry or by using the Van 't Hoff equation, though the calorimetric method is preferable. When both the standard enthalpy change and stability constant have been determined, the standard entropy change is easily calculated from the equation above. The fact that stepwise formation constants of complexes of the type MLn decrease in magnitude as n increases may be partly explained in terms of the entropy factor. Take the case of the formation of octahedral complexes.
The properties of quantum dots can be also tuned by the synthetic scheme, high temperature solvent/ligand mixtures that influence the nanocrystal properties. High-quality QD contrast agents are obtained at elevated temperatures; however, because they have lower water solubility, their usage as cell markers is limited. Further functionalization with hydrophilic ligands is required. The advantages of QD are represented by their fast action; they are able to label a target tissue or cell in seconds. In vivo studies show that QD are able to selectively label cancer cells, and they accumulate at tumor sites. Tumor cells labeled with QD can be tracked with multiphoton microscopy as they invade lung tissue. In both studies, spectral imaging and autofluorescent subtraction allowed multicolour in vivo visualization of cells and tissues. A major drawback of QD is their relatively high toxicity. Functionalizations with different substrates that increase bioaffinity and decrease toxicity are in progress. For instance, sulfur from the QD shell is able to form reversible disulfide bonds with a wide class of organic compounds.
Dehydroascorbate, the oxidized form, is then recycled back to ascorbate by endogenous antioxidants such as glutathione. In the eye, ascorbate is thought to protect against photolytically generated free-radical damage; higher plasma ascorbate is associated with lower risk of cataracts. Ascorbate may also provide antioxidant protection indirectly by regenerating other biological antioxidants such as α-tocopherol back to an active state. In addition, ascorbate is also a non-enzymatic reducing agent for mixed-function oxidases in the microsomal drug-metabolizing system that inactivates a wide variety of substrates such as drugs and environmental carcinogens.
Sources: en.wikipedia.org
The Child-Pugh score is a validated predictor of mortality after a major surgery. For example, Child class A patients have a 10% mortality rate and Child class B patients have a 30% mortality rate while Child class C patients have a 70–80% mortality rate after abdominal surgery. Elective surgery is usually reserved for those in Child class A patients. There is an increased risk for Child class B individuals, and they may require medical optimization. Overall, it is not recommended for Child class C patients to undergo elective surgery. In the past, the Child-Pugh classification was used to determine people who were candidates for a liver transplant. Child-Pugh class B is usually an indication for evaluation for transplant. However, there were many issues when applying this score to liver transplant eligibility. Thus, the MELD score was created. The Model for End-Stage Liver Disease (MELD) score was later developed and approved in 2002. It was approved by the United Network for Organ Sharing (UNOS) as a way to determine the allocation of liver transplants to awaiting people in the United States. It is also used as a validated survival predictor of cirrhosis, alcoholic hepatitis, acute liver failure, and acute hepatitis. The variables included bilirubin, INR, creatinine, and dialysis frequency. In 2016, sodium was added to the variables and the score is often referred to as MELD-Na. MELD-Plus is a further risk score to assess the severity of chronic liver disease. It was developed in 2017 as a result of a collaboration between Massachusetts General Hospital and IBM.
==== Dopamine ==== Dopamine is the principal prolactin-inhibiting factor. It acts on D2 receptors (D2R) on the lactotroph membrane. Two D2R isoforms (D2L and D2S) couple to Gi/Go proteins and produce inhibition through multiple time-dependent mechanisms:
== External links == Prof. Matthias Tschöp (16 May 2012). Medicine: Prof. Matthias Tschöp. Alexander von Humboldt Foundation. Prof. Matthias Tschöp, Chair of Metabolic Diseases, TUM School of Medicine
=== Birds and reptiles === The epidermis of birds and reptiles is closer to that of mammals, with a layer of dead keratin-filled cells at the surface, to help reduce water loss. A similar pattern is also seen in some of the more terrestrial amphibians such as toads. In these animals, there is no clear differentiation of the epidermis into distinct layers initially, as occurs in humans, with the change in cell type being relatively gradual. The mammalian epidermis always possesses at least a stratum germinativum and stratum corneum, but the other intermediate layers found in humans are not always distinguishable. Hair is a distinctive feature of mammalian skin, while feathers are (at least among living species) similarly unique to birds. Birds and reptiles have relatively few skin glands, although there may be a few structures for specific purposes, such as pheromone-secreting cells in some reptiles, or the uropygial gland of most birds.
Sources: en.wikipedia.org
The most common approach is liquid chromatography-tandem mass spectrometry, often after extraction from blood, urine, or tissue. Ultraviolet detection and nuclear magnetic resonance spectroscopy are used mainly for reference material characterization. Isotope-labeled internal standards improve accuracy.
Solid material is usually kept at -20 °C, desiccated, and protected from light. Dimethyl sulfoxide stocks should be stored cold and subjected to minimal freeze-thaw cycles. Aqueous solutions are generally less stable and should be prepared fresh when possible.
Legality depends on the country and the intended use. It is not an approved medicine, and some places restrict or ban sales for human consumption. Buyers should verify local rules and product documentation before procurement.
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.