The short version of circadian rhythm fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-07-22 and is reviewed periodically as new material appears.
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.
Because REV-ERB receptors are core clock components, SR9009 has been examined for effects on daily rhythms as well as metabolism. Research has explored whether the compound can shift or reinforce circadian gene expression in tissues such as liver and muscle. Some studies report improved metabolic markers in obese or diabetic mice, while others show context-dependent responses. Questions remain about which effects are direct, which are secondary to timing, and how they might differ across species.
SR9009 is a synthetic small molecule studied as an agonist of REV-ERB nuclear receptors. REV-ERB alpha and REV-ERB beta help regulate circadian rhythms and metabolic gene expression. In laboratory research, SR9009 has been used to probe how these receptors affect skeletal muscle, liver, and adipose tissue. The compound was identified in academic drug-discovery work and is often described in scientific literature by its chemical name and research code. It is not an approved medicine, and human clinical data remain limited or absent.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C20H24ClN3O4S | Reported for the free base |
| Molecular weight | 437.9 g/mol | Calculated from the formula |
| Primary target | REV-ERBα and REV-ERBβ | Nuclear receptors involved in circadian regulation |
| Solubility | Soluble in DMSO and ethanol | Poorly soluble in water |
| Typical storage | -20 °C, desiccated | Protect from light and moisture |
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 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.
== International Mass Spectrometry Foundation == The major awards from the International Mass Spectrometry Foundation are the Thomson Medal Award, the Curt Brunnée Award, and the Jochen Franzen Award.
=== Sodium channels === AM404 has also been reported to inhibit voltage-gated sodium channels in the peripheral nervous system, with much greater potency than its effects at previously proposed targets. Specifically, it inhibits Nav1.8 and 1.7 channels at nanomolar concentrations in vitro. AM404 injected into the hind paw of rats increase the pain threshold for the treated paw, but not the untreated paw, confirming the peripheral nature of this effect. It also lowers pain responses in a few other in vivo models when injected directly into the affected area. Other tested metabolites of paracetamol do not block pain-sensing sodium channels in vitro.
=== Chemical === Copernicium is the tenth and last member of the 6d series and is the heaviest group 12 element in the periodic table, below zinc, cadmium and mercury. It is predicted to differ significantly from the lighter group 12 elements. The valence s-subshells of the group 12 elements and period 7 elements are expected to be relativistically contracted most strongly at copernicium. This and the closed-shell configuration of copernicium result in it probably being a very noble metal. A standard reduction potential of +2.1 V is predicted for the Cn2+/Cn couple. Copernicium's predicted first ionization energy of 1155 kJ/mol almost matches that of the noble gas xenon at 1170.4 kJ/mol. Copernicium's metallic bonds should also be very weak, possibly making it extremely volatile like the noble gases, and potentially making it gaseous at room temperature. However, it should be able to form metal–metal bonds with copper, palladium, platinum, silver, and gold; these bonds are predicted to be only about 15–20 kJ/mol weaker than the analogous bonds with mercury. In opposition to the earlier suggestion, ab initio calculations at the high level of accuracy predicted that the chemistry of singly-valent copernicium resembles that of mercury rather than that of the noble gases. The latter result can be explained by the huge spin–orbit interaction which significantly lowers the energy of the vacant 7p1/2 state of copernicium. Once copernicium is ionized, its chemistry may present several differences from those of zinc, cadmium, and mercury.
A 2017 study finds that countries' coup-proofing strategies are heavily influenced by other countries with similar histories. Coup-proofing is more likely in former French colonies. A 2018 study in the Journal of Peace Research found that leaders who survive coup attempts and respond by purging known and potential rivals are likely to have longer tenures as leaders. A 2019 study in Conflict Management and Peace Science found that personalist dictatorships are more likely to take coup-proofing measures than other authoritarian regimes; the authors argue that this is because "personalists are characterized by weak institutions and narrow support bases, a lack of unifying ideologies and informal links to the ruler". In their 2022 book Revolution and Dictatorship: The Violent Origins of Durable Authoritarianism, political scientists Steven Levitsky and Lucan Way found that political-military fusion, where the ruling party is highly interlinked with the military and created the administrative structures of the military from its inception, is extremely effective at preventing military coups. For example, the People's Liberation Army was created by the Chinese Communist Party during the Chinese Civil War, and never instigated a military coup even after large-scale policy failures (i.e. the Great Leap Forward) or the extreme political instability of the Cultural Revolution. Some scholars have posited that the recruitment of foreign legionnaires into national armies can reduce the probability of military coups.
Lower Saxony is a coastal state (Land) in northwestern Germany. It is the second-largest state by land area, with 47,614 km2 (18,384 sq mi), and fourth-largest in population (8 million in 2021) among the 16 Länder of the Federal Republic of Germany. In rural areas, Northern Low Saxon and Saterland Frisian are spoken to varying degrees. Lower Saxony borders on (from north and clockwise) the North Sea, the states of Schleswig-Holstein, Hamburg, Mecklenburg-Vorpommern, Brandenburg, Saxony-Anhalt, Thuringia, Hesse and North Rhine-Westphalia, and the Netherlands. The state of Bremen forms two enclaves within Lower Saxony, one being the city of Bremen, the other its seaport, Bremerhaven (which is a semi-exclave, as it has a coastline). Lower Saxony thus borders more neighbours than any other single Bundesland. The state's largest cities are the state capital Hanover, Braunschweig (Brunswick), Oldenburg, Osnabrück, Wolfsburg, Göttingen, Salzgitter, Hildesheim, mainly situated in its central and southern parts, except Oldenburg. Lower Saxony is the only Bundesland that encompasses both maritime and mountainous areas. The northwestern area of the state, on the coast of the North Sea, is called East Frisia and the seven East Frisian Islands offshore are popular with tourists. In the extreme west of Lower Saxony is the Emsland, an economically emerging but rather sparsely populated area, once dominated by inaccessible swamps. The northern half of Lower Saxony, also known as the North German Plain, is almost invariably flat except for the gentle hills around the Bremen geestland.
Sources: en.wikipedia.org
The linear amino acid sequence of a protein is called the primary structure. The primary structure can be easily determined from the sequence of codons on the DNA gene that codes for it. In most proteins, the primary structure uniquely determines the 3-dimensional structure of a protein in its native environment. An exception is the misfolded prion protein involved in bovine spongiform encephalopathy. This structure is linked to the function of the protein. Additional structural information includes the secondary, tertiary and quaternary structure. A viable general solution to the prediction of the function of a protein remains an open problem. Most efforts have so far been directed towards heuristics that work most of the time.
==== Solid state ==== Few neptunium(III) coordination compounds are known, because Np(III) is readily oxidized by atmospheric oxygen while in aqueous solution. However, sodium formaldehyde sulfoxylate can reduce Np(IV) to Np(III), stabilizing the lower oxidation state and forming various sparingly soluble Np(III) coordination complexes, such as Np2(C2O4)3·11H2O, Np2(C6H5AsO3)3·H2O, and Np2[C6H4(OH)COO]3. Many neptunium(IV) coordination compounds have been reported, the first one being (Et4N)Np(NCS)8, which is isostructural with the analogous uranium(IV) coordination compound. Other Np(IV) coordination compounds are known, some involving other metals such as cobalt (CoNp2F10·8H2O, formed at 400 K) and copper (CuNp2F10·6H2O, formed at 600 K). Complex nitrate compounds are also known: the experimenters who produced them in 1986 and 1987 obtained single crystals by slow evaporation of the Np(IV) solution at ambient temperature in concentrated nitric acid and excess 2,2′-pyrimidine. The coordination chemistry of neptunium(V) has been extensively researched due to the presence of cation–cation interactions in the solid state, which had been already known for actinyl ions. Some known such compounds include the neptunyl dimer Na4(NpO4)2C12O12·8H2O and neptunium glycolate, both of which form green crystals. Neptunium(VI) compounds range from the simple oxalate NpO2C2O4 (which is unstable, usually becoming Np(IV)) to such complicated compounds as the green (NH4)4NpO2(CO3)3.
== Early years and education == Hans Charles Freeman was the first and only son of Karl and Lotte Freeman and was born in Breslau in Germany in 1929 (now Wrocław, Poland). In 1938, following a tip-off from a Nazi party member, Karl decided to relocate his Jewish family to Australia. Karl brought his knowledge of detergents (a novelty in Australia at the time) to his new homeland, applying it to the problem of cleaning blood-stained blankets that would otherwise be wasted. After the war, he founded K. H. Freeman Pty Ltd, a detergent and soap manufacturing company; Hans spent many weekends working in the factory, gaining a practical insight into chemistry. Hans adapted well to his new environment, quickly mastering his new language and demonstrating his outstanding scholastic ability. He was dux of his primary school, dux of Sydney Boys High in 1945, and took his bachelor's degree with the university medal in chemistry in 1949. He was one of the ten chemistry students in his class at Sydney Boys High to go on to become Professors of Chemistry. After receiving his MSc in 1952 under the supervision of Raymond Le Fèvre FRS, Freeman attended Caltech on a Rotary Foundation Fellowship where, at the urging of Linus Pauling, he learned the fundamentals of crystallography. He received a PhD in 1957 for his work on the structure of biuret hydrate, where he completed most of the calculations for the crystal structure by hand.
In December of that same year, both governments signed a Status of Forces Agreement (SOFA) regulating the presence and activities of U.S. soldiers and military personnel on Paraguayan soil. Foreign minister Rubén Ramírez Lezcano confirmed that those soldiers would have immunity in Paraguay.
Sources: en.wikipedia.org
The Indochinese spitting cobra (Naja siamensis) is a venomous spitting cobra whose venom consists of postsynaptic neurotoxins, metalloproteinases, powerful cardiotoxins, with cytolytic activity, and Phospholipase A2 with a diversity of activities. The LD50 of its venom is 1.07–1.42 mg/gram of mouse body weight. Cranial palsy and respiratory depression are reported to be more common after bites by Naja siamensis than by Naja kaouthia. Indochinese spitting cobras will use their venom for self-defense with little provocation, and as the name implies, are capable of spitting venom when alarmed, often at the face and eyes of the animal or human threatening them. A case report in the literature describes pain and irritation of the eyes, bilateral redness, excessive tear production and whitish discharge, with superficial corneal opacity but normal acuity.
=== Further === Burnside College ESPA College Gateshead College Harton Academy and Sixth Form Newcastle College Newcastle Sixth Form College Tyne Metropolitan College South Tyneside College Sunderland College
Vitamin K is absorbed along with dietary fat from the small intestine and transported by chylomicrons in the circulation. Most of vitamin K1 is carried by triacylglycerol-rich lipoproteins (TRL) and rapidly cleared by the liver; only a small amount is released into the circulation and carried by LDL-C and HDL-C. MK-4 is carried by the same lipoproteins (TRL, LDL-C, and HDL-C) and cleared fast as well. The long-chain menaquinones are absorbed in the same way as vitamin K1 and MK-4 but are efficiently redistributed by the liver in predominantly LDL-C (VLDL-C). Since LDL-C has a long half-life in the circulation, these menaquinones can circulate for extended times resulting in higher bioavailability for extra-hepatic tissues as compared to vitamin K1 and MK-4. Accumulation of vitamin K in extra-hepatic tissues has direct relevance to vitamin K functions not related to hemostasis.
Sources: en.wikipedia.org
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.
It binds to REV-ERBα and REV-ERBβ, nuclear receptors involved in circadian and metabolic gene regulation. This can alter transcription of genes related to lipid and glucose metabolism in experimental models.
No controlled human trials have established that effect. Endurance findings come primarily from rodent studies, and human responses remain unknown.
SR9009 is a synthetic research compound that acts on REV-ERB nuclear receptors. It is not approved for human use and is sold only as a research chemical. Its effects have been studied mainly in cells and rodents.