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Beta-cubebene
Cubebenes are a pair of chemical compounds, classified as sesquiterpenes, first isolated from ''Piper cubeba ''Piper cubeba'', cubeb or tailed pepper is a plant in genus ''Piper'', cultivated for its fruit and essential oil. It is mostly grown in Java and Sumatra, hence sometimes called Java pepper. The fruits are gathered before they are ripe, and ca ...'' berries, known as cubebs. The volatile oil from the distillation of cubebs is a pale green or blue-yellow viscous liquid with a warm woody, slightly camphoraceous odor consisting of cubebene which comes in two forms, α- and β-cubebene, both with the molecular formula C15H24. They differ only in the position of a double bond which is endocyclic (part of the five-membered ring) in α-cubebene, but exocyclic in β-cubebene. References {{reflist Sesquiterpenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sesquiterpene
Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many unique combinations. Biochemical modifications such as oxidation or rearrangement produce the related sesquiterpenoids. Sesquiterpenes are found naturally in plants and insects, as semiochemicals, e.g. defensive agents or pheromones. Biosynthesis and examples The reaction of geranyl pyrophosphate with isopentenyl pyrophosphate results in the 15-carbon farnesyl pyrophosphate (FPP), which is an intermediate in the biosynthesis of sesquiterpenes such as farnesene. Cyclic sesquiterpenes are more common than cyclic monoterpenes because of the increased chain length and additional double bond in the sesquiterpene precursors. In addition to common six-membered ring systems such as the ones found in zingiberene and bisacurone, cyclization of one end of the chain to the other end can l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piper Cubeba
''Piper cubeba'', cubeb or tailed pepper is a plant in genus ''Piper'', cultivated for its fruit and essential oil. It is mostly grown in Java and Sumatra, hence sometimes called Java pepper. The fruits are gathered before they are ripe, and carefully dried. Commercial cubeb consists of the dried berries, similar in appearance to black pepper, but with stalks attached – the "tails" in "tailed pepper". The dried pericarp is wrinkled, and its color ranges from grayish brown to black. The seed is hard, white and oily. The odor of cubeb is described as agreeable and aromatic and the taste as pungent, acrid, slightly bitter and persistent. It has been described as tasting like allspice, or like a cross between allspice and black pepper. Cubeb came to Europe via India through the trade with the Arabs. The name ''cubeb'' comes from Arabic ' () by way of Old French ''quibibes''. Cubeb is mentioned in alchemical writings by its Arabic name. In his ''Theatrum Botanicum'', John P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volatile Oil
An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the oil of the plant from which they were extracted, such as oil of clove. An essential oil is essential in the sense that it contains the essence of the plant's fragrance—the characteristic fragrance of the plant from which it is derived. The term "essential" used here does ''not'' mean indispensable or usable by the human body, as with the terms essential amino acid or essential fatty acid, which are so called because they are nutritionally required by a living organism. Essential oils are generally extracted by distillation, often by using steam. Other processes include expression, solvent extraction, ''sfumatura'', absolute oil extraction, resin tapping, wax embedding, and cold pressing. They are used in perfumes, cosmetics, soaps, air f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double Bond
In chemistry, a double bond is a covalent bond between two atoms involving four bonding electrons as opposed to two in a single bond. Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist between two different elements: for example, in a carbonyl group between a carbon atom and an oxygen atom. Other common double bonds are found in azo compounds (N=N), imines (C=N), and sulfoxides (S=O). In a skeletal formula, a double bond is drawn as two parallel lines (=) between the two connected atoms; typographically, the equals sign is used for this. Double bonds were first introduced in chemical notation by Russian chemist Alexander Butlerov. Double bonds involving carbon are stronger and shorter than single bonds. The bond order is two. Double bonds are also electron-rich, which makes them potentially more reactive in the presence of a strong electron acceptor (as in addition reactions of the halogens). File:Ethene structural.svg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exocyclic
In organic chemistry, an alicyclic compound contains one or more all-carbon rings which may be either saturated or unsaturated, but do not have aromatic character. Alicyclic compounds may have one or more aliphatic side chains attached. The simplest alicyclic compounds are the monocyclic cycloalkanes: cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, and so on. Bicyclic alkanes include bicycloundecane, decalin, and housane. Polycyclic alkanes include cubane, basketane, and tetrahedrane. Spiro compounds have two or more rings that are connected through only one carbon atom. The mode of ring-closing in the formation of many alicyclic compounds can be predicted by Baldwin's rules. Otto Wallach, a German chemist, received the 1910 Nobel Prize in Chemistry for his work on alicyclic compounds. Cycloalkenes Monocyclic cycloalkenes are cyclopropene, cyclobutene, cyclopentene, cyclohexene, cycloheptene, cyclooctene, and so on. Bicyclic alkenes incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
