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| Names | |
|---|---|
| Preferred IUPAC name (2E,2′E)-2,2′-(1,3-Dioxolane-4,5-diylidene)bis(phenylacetic acid) | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider | |
PubChem CID | |
| UNII | |
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| Properties | |
| C19H14O6 | |
| Molar mass | 338.315 g·mol−1 |
| Appearance | White solid |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
Ustalic acid is a naturally occurring chemical compound found in the poisonous mushroom Tricholoma ustale .
The compound was first reported by Japanese researcher Hirokazu Kawagishi and colleagues in 2002, who isolated about 190 milligrams of the chemical from 30.3 kg (67 lb) of fresh mushrooms and determined its complete structure. [1]
Ustalic acid is an inhibitor of the sodium-potassium pump (Na+/K+-ATPase), found in the plasma membrane of all animal cells. Physiologically, inhibition of the sodium-potassium pump generally causes diarrhea, as it prevents water reabsorption from the intestines. When force-fed to mice, ustalic acid causes them to sit still in a crouched position, hesitant to move, and induces tremors and abdominal contractions. High enough concentrations of the toxin (10 milligrams per mouse) cause death. [1] Biosynthetically, ustalic acid is thought to originate from oxidative cleavage of the red pigment phlebiarubron. [2]
A low-yield total synthesis of the dimethyl ester of ustalic acid was reported in 2006, starting with phlebiarubrone. The oxidation was achieved with lead tetraacetate. [2] Hayakawa and colleagues reported a more efficient synthesis in 2008, using sesamol as a starting point. This procedure requires eight steps, and uses Suzuki–Miyaura coupling and oxidation of methylene acetal. [3]
Sodium cyanide is a poisonous compound with the formula NaCN. It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its high reactivity toward metals. It is a moderately strong base.
ATPases (EC 3.6.1.3, Adenosine 5'-TriPhosphatase, adenylpyrophosphatase, ATP monophosphatase, triphosphatase, SV40 T-antigen, ATP hydrolase, complex V (mitochondrial electron transport), (Ca2+ + Mg2+)-ATPase, HCO3−-ATPase, adenosine triphosphatase) are a class of enzymes that catalyze the decomposition of ATP into ADP and a free phosphate ion or the inverse reaction. This dephosphorylation reaction releases energy, which the enzyme (in most cases) harnesses to drive other chemical reactions that would not otherwise occur. This process is widely used in all known forms of life.
The sodium–potassium pump is an enzyme found in the membrane of all animal cells. It performs several functions in cell physiology.
Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash.
Sodium nitrite is an inorganic compound with the chemical formula NaNO2. It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic. From an industrial perspective, it is the most important nitrite salt. It is a precursor to a variety of organic compounds, such as pharmaceuticals, dyes, and pesticides, but it is probably best known as a food additive used in processed meats and (in some countries) in fish products.
Potassium cyanide is a compound with the formula KCN. It is a colorless salt, similar in appearance to sugar, that is highly soluble in water. Most KCN is used in gold mining, organic synthesis, and electroplating. Smaller applications include jewellery for chemical gilding and buffing. Potassium cyanide is highly toxic, and a dose of 200 to 300 milligrams will kill nearly any human.
Ouabain or also known as g-strophanthin, is a plant derived toxic substance that was traditionally used as an arrow poison in eastern Africa for both hunting and warfare. Ouabain is a cardiac glycoside and in lower doses, can be used medically to treat hypotension and some arrhythmias. It acts by inhibiting the Na/K-ATPase, also known as the sodium–potassium ion pump. However, adaptations to the alpha-subunit of the Na+/K+-ATPase via amino acid substitutions, have been observed in certain species, namely some herbivore- insect species, that have resulted in toxin resistance.
Cerberin is a type of cardiac glycoside, a steroidal class found in the seeds of the dicotyledonous angiosperm genus Cerbera; including the suicide tree and the sea mango. This class includes digitalis-like agents, channel-blockers that as a group have found historic uses as cardiac treatments, but which at higher doses are extremely toxic; in the case of cerberin, consumption of the C. odollam results in poisoning with presenting nausea, vomiting, and abdominal pain, often leading to death. The natural product has been structurally characterized, its toxicity is clear—it is often used as an intentional human poison in third-world countries, and accidental poisonings with fatalities have resulted from individuals even indirectly consuming the agent—but its potentially therapeutic pharmacologic properties are very poorly described.
Palytoxin, PTX or PLTX is an intense vasoconstrictor, and is considered to be one of the most poisonous non-protein substances known, second only to maitotoxin in terms of toxicity in mice.
In chemistry, a vanadate is an anionic coordination complex of vanadium. Often vanadate refers to oxoanions of vanadium, most of which exist in its highest oxidation state of +5. The complexes [V(CN)6]3− and [V2Cl9]3− are referred to as hexacyanovanadate(III) and nonachlorodivanadate(III), respectively.
Gastric hydrogen potassium ATPase, also known as H+/K+ ATPase, is an enzyme which functions to acidify the stomach. It is a member of the P-type ATPases, also known as E1-E2 ATPases due to its two states.
A symporter is an integral membrane protein that is involved in the transport of two different molecules across the cell membrane in the same direction. The symporter works in the plasma membrane and molecules are transported across the cell membrane at the same time, and is, therefore, a type of cotransporter. The transporter is called a symporter, because the molecules will travel in the same direction in relation to each other. This is in contrast to the antiport transporter. Typically, the ion(s) will move down the electrochemical gradient, allowing the other molecule(s) to move against the concentration gradient. The movement of the ion(s) across the membrane is facilitated diffusion, and is coupled with the active transport of the molecule(s). In symport, two molecule move in a 'similar direction' at the 'same time'. For example, the movement of glucose along with sodium ions.
Pumiliotoxin 251D is a toxic organic compound. It is found in the skin of poison frogs from the genera Dendrobates, Epipedobates, Minyobates, and Phyllobates and toads from the genus Melanophryniscus. Its name comes from the pumiliotoxin family (PTXs) and its molecular mass of 251 daltons. When the toxin enters the bloodstream through cuts in the skin or by ingestion, it can cause hyperactivity, convulsions, cardiac arrest and ultimately death. It is especially toxic to arthropods, even at low concentrations.
Arenobufagin is a cardiotoxic bufanolide steroid secreted by the Argentine toad Bufo arenarum. It has effects similar to digitalis, blocking the Na+/K+ pump in heart tissue.
Sodium ions are necessary in small amounts for some types of plants, but sodium as a nutrient is more generally needed in larger amounts by animals, due to their use of it for generation of nerve impulses and for maintenance of electrolyte balance and fluid balance. In animals, sodium ions are necessary for the aforementioned functions and for heart activity and certain metabolic functions. The health effects of salt reflect what happens when the body has too much or too little sodium. Characteristic concentrations of sodium in model organisms are: 10 mM in E. coli, 30 mM in budding yeast, 10 mM in mammalian cell and 100 mM in blood plasma.
Convallatoxin is a glycoside extracted from Convallaria majalis.
Proton pump inhibitors (PPIs) block the gastric hydrogen potassium ATPase (H+/K+ ATPase) and inhibit gastric acid secretion. These drugs have emerged as the treatment of choice for acid-related diseases, including gastroesophageal reflux disease (GERD) and peptic ulcer disease. PPIs also can bind to other types of proton pumps such as those that occur in cancer cells and are finding applications in the reduction of cancer cell acid efflux and reduction of chemotherapy drug resistance.
Tricholoma ustale, commonly known as the burnt knight, is a species of mushroom in the large genus Tricholoma. It is found in Asia, Europe, and North America, though those from North America may represent one or more different species.
Gambierol is a marine polycyclic ether toxin which is produced by the dinoflagellate Gambierdiscus toxicus. Gambierol is collected from the sea at the Rangiroa Peninsula in French Polynesia. The toxins are accumulated in fish through the food chain and can therefore cause human intoxication. The symptoms of the toxicity resemble those of ciguatoxins, which are extremely potent neurotoxins that bind to voltage-sensitive sodium channels and alter their function. These ciguatoxins cause ciguatera fish poisoning. Because of the resemblance, there is a possibility that gambierol is also responsible for ciguatera fish poisoning. Because the natural source of gambierol is limited, biological studies are hampered. Therefore, chemical synthesis is required.
Calotropin is a toxic cardenolide found in plants in the family Asclepiadoideae. In extreme cases, calotropin poisoning can cause respiratory and cardiac failure. Accidental poisoning is common in livestock who have ingested milkweed. Calotropin is commonly stored as a defense mechanism by insects that eat milkweeds as their main food source.
