REV-ERB comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-10-24. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Preclinical reports describe effects on exercise endurance, mitochondrial content, and lipid profiles in rodents, but these findings come from specific experimental conditions. Many studies use high doses or delivery methods that may not translate directly to human use. SR9009 has been reported to have low oral bioavailability and a short half-life, which complicates interpretation of oral dosing studies. It is not established as safe or effective for any indication. Literature discussions often separate its pharmacological mechanism from unverified claims made in fitness and supplement markets.
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.
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 |
|---|---|---|
| Molecular formula | C20H24ClN3O4S | Derived from published structure. |
| Molecular weight | 437.94 g/mol | Calculated value. |
| Appearance | White to off-white solid | Typical for purified research samples. |
| Solubility | DMSO, ethanol; low in water | Class: poorly water-soluble. |
| Typical storage | -20 °C, desiccated, protected from light | Limits degradation. |
Physicochemical behavior influences handling. SR9009 is described as a solid with limited aqueous solubility, so organic solvents such as dimethyl sulfoxide or ethanol are common in research stock solutions. Aqueous dilution can produce precipitates if the organic content is too low. Light, heat, and repeated freeze-thaw cycles may affect stability. Storage recommendations usually specify a desiccated freezer environment protected from light, but exact stability data depend on the formulation and matrix.
Detection in biological samples can be complicated by rapid metabolism and low circulating concentrations. Some studies report phase I and phase II metabolites, and analytical methods may need to target those species in addition to the parent compound. Immunoassays are not broadly available, so mass spectrometry remains the main confirmatory approach. For anti-doping testing, laboratories look for SR9009 and its metabolites using validated LC-MS methods. Open questions include how long metabolites remain detectable and how different routes of administration alter detection windows.
In laboratory settings, SR9009 is typically characterized by liquid chromatography–mass spectrometry (LC-MS) or high-performance liquid chromatography with ultraviolet detection (HPLC-UV). These methods can confirm identity and estimate purity, but they require reference standards for accurate quantification. Because SR9009 is not a licensed pharmaceutical, no harmonized pharmacopeial monograph exists. Laboratories often validate in-house methods for matrices such as plasma, urine, or cell culture media. Sample preparation may involve protein precipitation or liquid-liquid extraction before analysis.
== Expression/Production systems == Different organisms may be used to express a gene's target protein, and the expression vector used will therefore have elements specific for use in the particular organism. The most commonly used organism for protein production is the bacterium Escherichia coli. However, not all proteins can be successfully expressed in E. coli, or be expressed with the correct form of post-translational modifications such as glycosylations, and other systems may therefore be used.
By choosing porous graphitic carbon as a stationary phase for liquid chromatography, even non derivatized glycans can be analyzed. Electrospray ionisation (ESI) is frequently used for this application.
The chelate effect increases as the number of chelate rings increases. For example, the complex [Ni(dien)2)]2+ is more stable than the complex [Ni(en)3)]2+; both complexes are octahedral with six nitrogen atoms around the nickel ion, but dien (diethylenetriamine, 1,4,7-triazaheptane) is a tridentate ligand and en is bidentate. The number of chelate rings is one less than the number of donor atoms in the ligand. EDTA (ethylenediaminetetracetic acid) has six donor atoms so it forms very strong complexes with five chelate rings. Ligands such as DTPA, which have eight donor atoms are used to form complexes with large metal ions such as lanthanide or actinide ions which usually form 8- or 9-coordinate complexes. 5-membered and 6-membered chelate rings give the most stable complexes. 4-membered rings are subject to internal strain because of the small inter-bond angle is the ring. The chelate effect is also reduced with 7- and 8- membered rings, because the larger rings are less rigid, so less entropy is lost in forming them.
Sources: en.wikipedia.org
=== Design of scientific investigations === Aarons has defined pharmacokinetics (PK) as the study of the complex chain of events that links a dose of drugs administered to a patient and the expected effect or response. PK is based on analysing the concentration of drugs and tracking how they are absorbed, distributed, metabolised and excreted within the patient. Some of his work has involved using optimal design theory to explore what makes a successful scientific investigation for pharmacokinetic studies and has said that this "involves the selection and a careful balance of a number of design factors, including the number and location of measurement times and the number of subjects to include in the study." According to Aarons, population pharmacokinetics studies which focus on what happens to the substances administered to a patient would need specific design factors that apply "statistical experimental design principles to non-linear population pharmacokinetic models." A later paper co-authored by Aarons, reviews the different approaches to optimal design of population pharmacokinetic and pharmacodynamic experiments and notes that some of the options may raise concerns at to their practicality. The paper did, however, conclude "that as the awareness about the benefits of this approach increases, more people will embrace it and ultimately will lead to more efficient population pharmacokinetic and pharmacodynamic experiments."
=== Addiction remission === The term fen-phen was created in 1994 when Pietr Hitzig and Richard B. Rothman reported that this combination could presumptively remit alcohol and cocaine craving. The authors suggested that other combined dopamine and serotonin agonists or precursors might share this therapeutic potential. Subsequent experiments in rats supported these preliminary reports. In 2006 it was confirmed that the combination of phentermine and the serotonin precursor 5-hydroxytryptophan (5-HTP), in place of fenfluramine, significantly decreased alcohol withdrawal seizures in rats. Intramural National Institutes of Health (NIH) double-blind protocols to demonstrate the efficacy of fen-phen in alcohol and cocaine addiction were designed, but never performed.
=== Absorbance === When components are detected optically, the mobile phase should have high transmittance at the wavelength the detector uses. Most solvents are more transparent at longer wavelengths. Consequently, researchers usually speak of "cutoff wavelengths" of solvents. A solvent's cutoff wavelength is the wavelength at which the absorbance of the solvent equals 1 AU. A modifier should only be used with light above the cutoff wavelength. Commonly used values: ACN 190 nm, acetone 330 nm, diethylamine 275 nm, EtOH 210 nm, IPA 205 nm, isopropyl ether 220 nm, MeOH 205 nm, 1-propanol 210 nm, THF 230 nm. Most peptides only absorb at low wavelengths in the ultra-violet spectrum (typically less than 225 nm), and consequently for RP-LC with peptides, the most commonly used modifier is ACN.
The capacity to be metabolized by 5α-reductase and the AR activity of the resultant metabolites appears to be one of the major, if not the most important determinant of the androgenic–myotrophic ratio for a given AAS. AAS that are not potentiated by 5α-reductase or that are weakened by 5α-reductase in androgenic tissues have a reduced risk of androgenic side effects such as acne, androgenic alopecia (male-pattern baldness), hirsutism (excessive male-pattern hair growth), benign prostatic hyperplasia (prostate enlargement), and prostate cancer, while incidence and magnitude of other effects such as muscle hypertrophy, bone changes, voice deepening, and changes in sex drive show no difference.
Sources: en.wikipedia.org
SR9009 is a synthetic REV-ERB agonist used in laboratory research. It is not an approved drug, and its effects in humans are not well characterized. It is often sold as a research chemical under the name Stenabolic.
No. SR9009 targets the nuclear receptors REV-ERBα and REV-ERBβ, not the androgen receptor. This mechanism differs from selective androgen receptor modulators and from exercise mimetics that act on PPARδ.
Published evidence is mainly preclinical, using cell cultures and animal models. Controlled human trials are not well documented in the public literature. Claims about human performance or health effects therefore remain unsupported by robust clinical data.
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.