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Chromane
Chromane (benzodihydropyran) is a heterocyclic chemical compound with the chemical formula C9H10O. Chromane is a structural feature of more complex compounds including E vitamins (tocopherols and tocotrienols), Dianin's compound, and the pharmaceutical drugs troglitazone, ormeloxifene Ormeloxifene, also known as centchroman, is one of the selective estrogen receptor modulators, or SERMs, a class of medication which acts on the estrogen receptor. It is best known as a nonsteroidal oral contraceptive which is taken once per w ..., and nebivolol. Such compounds are sometimes described as chromans. See also * Chromene (benzopyran) References External links * * {{heterocyclic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin E
Vitamin E is a group of eight compounds related in molecular structure that includes four tocopherols and four tocotrienols. The tocopherols function as fat-soluble antioxidants which may help protect cell membranes from reactive oxygen species. Vitamin E is classified as an essential nutrient for humans. Various government organizations recommend that adults consume between 3 and 15 mg per day, while a 2016 worldwide review reported a median dietary intake of 6.2 mg per day. Sources rich in vitamin E include seeds, nuts, vegetable oil, seed oils, Peanut butter#Nutritional profile, peanut butter, food fortification, vitamin E–fortified foods, and dietary supplements. Symptomatic vitamin E deficiency is rare, usually caused by an underlying problem with digesting dietary fat rather than from a diet low in vitamin E. Deficiency can cause neurological disorders. Tocopherols and tocotrienols both occur in α (alpha), β (beta), γ (gamma), and δ (delta) forms, as dete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Troglitazone
Troglitazone is an antidiabetic and anti-inflammatory drug, and a member of the drug class of the thiazolidinediones. It was prescribed for people with diabetes mellitus type 2. It was patented in 1983 and approved for medical use in 1997. It was subsequently withdrawn. Mechanism of action Troglitazone, like the other thiazolidinediones ( pioglitazone and rosiglitazone), works by activating peroxisome proliferator-activated receptors (PPARs). Troglitazone is a ligand to both PPARα and – more strongly – PPARγ. Troglitazone also contains an α-Tocopherol moiety, potentially giving it vitamin E-like activity in addition to its PPAR activation. It has been shown to reduce inflammation. Troglitazone use was associated with a decrease of nuclear factor kappa-B (NF-κB) and a concomitant increase in its inhibitor (IκB). NFκB is an important cellular transcription regulator for the immune response. History Troglitazone was developed by Daiichi Sankyo (Japan). In t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromene
4H-1-Benzopyran is an organic compound with the formula . It is one of two isomers of benzopyran, the other being 2H-1-benzopyran, which is more prevalent. It can be viewed as the fusion of a benzene ring to a heterocyclic pyran ring. Some benzopyrans have shown anticancerous activity ''in vitro''. The radical form of benzopyran is paramagnetic. The unpaired electron is delocalized over the whole benzopyran molecule, rendering it less reactive than one would expect otherwise. A similar example is the cyclopentadienyl radical. Commonly, benzopyran is encountered in the reduced state, in which it is partially saturated with one hydrogen atom, introducing a tetrahedral CH2 group in the pyran ring. Therefore, there are many structural isomers owing to the multiple possible positions of the oxygen atom and the tetrahedral carbon atom: Nomenclature According to current IUPAC nomenclature, the name chromene used in previous recommendations is retained; however, systematic ‘ben ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzopyran
4H-1-Benzopyran is an organic compound with the formula . It is one of two isomers of benzopyran, the other being 2H-1-Benzopyran, 2H-1-benzopyran, which is more prevalent. It can be viewed as the fusion of a benzene ring to a heterocyclic pyran ring. Some benzopyrans have shown anticancerous activity ''in vitro''. The radical (chemistry), radical form of benzopyran is paramagnetic. The unpaired electron is delocalized over the whole benzopyran molecule, rendering it less reactive than one would expect otherwise. A similar example is the cyclopentadienyl radical. Commonly, benzopyran is encountered in the reduced state, in which it is partially saturated with one hydrogen atom, introducing a tetrahedral CH2 group in the pyran ring. Therefore, there are many structural isomers owing to the multiple possible positions of the oxygen atom and the tetrahedral carbon atom: Nomenclature According to current IUPAC nomenclature, the name chromene used in previous recommendations i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tocopherol
Tocopherols (; TCP) are a class of organic compounds comprising various methylated phenols, many of which have vitamin E activity. Because the vitamin activity was first identified in 1936 from a dietary fertility factor in rats, it was named ''tocopherol'', from Greek τόκος ''tókos'' 'birth' and φέρειν ''phérein'' 'to bear or carry', that is 'to carry a pregnancy', with the ending ''-ol'' signifying its status as a chemical alcohol. α-Tocopherol is the main source found in supplements and in the European diet, where the main dietary sources are olive and sunflower oils, while γ-tocopherol is the most common form in the American diet due to a higher intake of soybean and corn oil. Forms Vitamin E exists in eight different forms, four tocopherols and four tocotrienols. All feature a chromane ring, with a hydroxyl group that can donate a hydrogen atom to reduce free radicals and a hydrophobic side chain that allows for penetration into biological membranes. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tocotrienol
Tocotrienols are plant-derived natural products belonging to the vitamin E family of diterpenoids. They exist as four isomers (alpha, beta, gamma, delta), each differing in the number and position of methyl groups on their chromanol ring. Tocotrienols are distinguished from the closely related tocopherols by their side chains: tocotrienols have three unsaturated isoprenoid double bonds, whereas tocopherols have a fully saturated side chain. Tocotrienols are compounds naturally occurring in some foods sources, the richest being palm oil, but to a lesser extent rice bran oil, barley, oats, and certain seeds, nuts and grains, and the oils derived from them. Chemically, different analogues of vitamin E all show some activity as a chemical antioxidant, but do not all have the same vitamin E equivalence. Tocotrienols demonstrate activity depending on the type of antioxidant performance being measured. All tocotrienols have some physical antioxidant activity due to an ability to d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahydroquinoline
Tetrahydroquinoline is an organic compound that is the semi-hydrogenated derivative of quinoline. It is a colorless oil. Use Substituted derivatives of tetrahydroquinoline are common in medicinal chemistry. Oxamniquine, dynemycin, viratmycin, and nicainoprol are bioactive tetrahydroquinolines. Typically tetrahydroquinoline derivatives are prepared by hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to redox, reduce or Saturated ... of the corresponding quinoline using heterogeneous catalysts. Synthesis Tetrahydroquinolines are produced by hydrogenation of quinolines. Because the hydrogenation is reversible, tetrahydroquinoline has been often examined as a hydrogen-donor solvent in coal liquifaction. Using homogeneous catalysts, asymmetric hydrogenation has been demonstrated. It can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetralin
Tetralin (1,2,3,4-tetrahydronaphthalene) is a hydrocarbon having the chemical formula C10H12. It is a partially hydrogenated derivative of naphthalene. It is a colorless liquid that is used as a hydrogen-donor solvent. Production Tetralin is produced by the catalytic hydrogenation of naphthalene. Although nickel catalysts are traditionally employed, many variations have been evaluated. Over-hydrogenation converts tetralin into decahydronaphthalene ( decalin). Rarely encountered is dihydronaphthalene ( dialin). Laboratory methods In a classic named reaction called the Darzens tetralin synthesis, named for Auguste Georges Darzens (1926), derivatives can be prepared by intramolecular electrophilic aromatic substitution reaction of a 1-aryl-pent-4-ene using concentrated sulfuric acid, Uses Tetralin is used as a hydrogen-donor solvent, for example in coal liquifaction. It functions as a source of H2, which is transferred to the coal. The partially hydrogenated coal is m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocyclic
A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of organic heterocycles. Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. More than half of known compounds are heterocycles. 59% of US FDA-approved drugs contain nitrogen heterocycles. Classification The study of organic heterocyclic chemistry focuses especially on organic unsaturated derivatives, and the preponderance of work and applications involves unstrained organic 5- and 6-membered rings. Included are pyridine, thiophene, pyrrole, and furan. Another large class of organic heterocycles refers to those fused to benzene rings. For example, the fused benzene derivatives of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken or new bonds formed or both. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, usin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dianin's Compound
Dianin's compound (4-''p''-hydroxyphenyl-2,2,4-trimethylchroman) was first prepared by Aleksandr Dianin in 1914. This compound is a condensation isomer of bisphenol A and acetone and of special importance in host–guest chemistry because it can form a large variety of clathrates with suitable guest molecules. One example is the clathrate of Dianin's compound with morpholine. Slow evaporation of a solution containing both organic compounds yields crystals. Each asymmetric unit cell making up the crystal contains six chroman molecules of which two are deprotonated and two protonated morpholine molecules. The six chroman molecules are racemate In chemistry, a racemic mixture or racemate () is a mixture that has equal amounts (50:50) of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as r ... pairs. References {{Reflist Clathrates 4-Hydroxyphenyl compounds Russian inventions Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
