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Betulin
Betulin is an abundant, naturally occurring triterpene. It is commonly isolated from the bark of birch trees, hence its name, from '' betula''. It forms up to 30% of the dry weight of silver birch bark. It is also found in birch sap. '' Inonotus obliquus'' contains betulin. The compound in the bark gives the tree its white color which appears to protect the tree from mid-winter overheating by the sun. As a result, birches are some of the northernmost occurring deciduous trees. History Betulin was discovered in 1788 by German- Russian chemist Johann Tobias Lowitz. Chemistry Chemically, betulin is a triterpenoid of lupane structure. It has a pentacyclic ring structure, and hydroxyl groups in positions C3 and C28. See also * Abietic acid * Stanol ester * Phytosterol Phytosterols are phytosteroids, similar to cholesterol, that serve as structural components of biological membranes of plants. They encompass plant sterols and stanol ester, stanols. More than 250 ster ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betula Pendula
''Betula pendula'', commonly known as silver birch, warty birch, European white birch, or East Asian white birch, is a species of tree in the family (biology), family Betulaceae, native plant, native to Europe and parts of Asia, though in southern Europe, it is only found at higher altitudes. Its range extends into Siberia, China, and southwest Asia in the mountains of northern Turkey, the Caucasus, and northern Iran. It has been introduced into North America, where it is known as the European white birch or weeping birch and is considered Invasive species, invasive in some states in the United States and parts of Canada. The silver birch is a medium-sized deciduous tree that owes its common name to the white peeling bark on the trunk. The twigs are slender and often pendulous and the leaves are roughly triangular with Glossary of leaf morphology#Edge, doubly serrate margins and turn yellow and brown in autumn before they fall. The flowers are catkins and the light, winged se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birch Sap
Birch sap, birch water or birch juice is the sap directly tapped from birch trees, '' Betula pubescens'' (white birch), ''Betula pendula'' (silver birch), '' Betula lenta'', '' Betula papyrifera'', and '' Betula fontinalis''. Birch sap may be consumed both fresh and naturally fermented. When fresh, it is a clear and colourless liquid, often slightly sweet with a slightly silky texture. After two to three days, the sap starts fermenting and the taste becomes more acidic. Birch sap is a traditional beverage in boreal and hemiboreal regions of the Northern Hemisphere as well as parts of northern China. Harvest Birch sap is collected only at the break of winter and spring when the sap moves intensively. Birch sap collection is done by drilling a hole into the tree trunk and leading the sap into a container via some conduit (a tube or simply a thin twig); the sap will flow along it because of the surface tension. The wound is then plugged to minimise infection. Birch sap h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birch Bark
Birch bark or birchbark is the bark of several Eurasian and North American birch trees of the genus ''Betula''. For all practical purposes, birch bark's main layers are the outer dense layer, white on the outside, and the inner porous layer (cambium). For vast majority of crafts, the outer bark is used. In many languages it has a separate name. For example, in Russian "birch bark" is "beryozovaya kora", while the outer birch bark is "beryosta". The strong and water-resistant cardboard-like outer bark can be easily cut, bent, and sewn, which has made it a valuable building, crafting, and writing material, since pre-historic times. Today, birch bark remains a popular type of wood for various handicrafts and arts. Birch bark also contains substances of medicinal and chemical interest. Some of those products (such as betulin) also have fungicidal properties that help preserve bark artifacts, as well as food preserved in bark containers. Collection and storage Removing birch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birch
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech- oak family Fagaceae. The genus ''Betula'' contains 30 to 60 known taxa of which 11 are on the IUCN 2011 Red List of Threatened Species. They are typically short-lived pioneer species and are widespread in the Northern Hemisphere, particularly in northern areas of temperate climates and in boreal climates. Birch wood is used for a wide range of purposes. Description Birch species are generally small to medium-sized trees or shrubs, mostly of northern temperate and boreal climates. The simple leaves are alternate, singly or doubly serrate, feather-veined, petiolate and stipulate. They often appear in pairs, but these pairs are really borne on spur-like, two-leaved, lateral branchlets. The fruit is a small samara, although the wings may be obscure in some species. They differ from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lupane Triterpene compounds)
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Lupane may refer to: *Lupane District, Zimbabwe **Lupane State University *Lupane (compound) (a type of triterpene Triterpenes are a class of terpenes composed of six isoprene units with the molecular formula C30H48; they may also be thought of as consisting of three terpene units. Animals, plants and fungi all produce triterpenes, including squalene, the pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Alcohols
In chemistry, an alcohol (), is a type of organic compound that carries at least one hydroxyl () functional group bound to a saturated carbon atom. Alcohols range from the simple, like methanol and ethanol, to complex, like sugar alcohols and cholesterol. The presence of an OH group strongly modifies the properties of hydrocarbons, conferring hydrophilic (water-loving) properties. The OH group provides a site at which many reactions can occur. History The flammable nature of the exhalations of wine was already known to ancient natural philosophers such as Aristotle (384–322 BCE), Theophrastus (–287 BCE), and Pliny the Elder (23/24–79 CE). However, this did not immediately lead to the isolation of alcohol, even despite the development of more advanced distillation techniques in second- and third-century Roman Egypt. An important recognition, first found in one of the writings attributed to Jābir ibn Ḥayyān (ninth century CE), was that by adding salt to boiling win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Alcohols
A primary alcohol is an Alcohol (chemistry), alcohol in which the hydroxy group is bonded to a primary carbon atom. It can also be defined as a molecule containing a “–CH2OH” group. In contrast, a secondary alcohol has a formula “–CHROH” and a tertiary alcohol has a formula “–CR2OH”, where “R” indicates a carbon-containing group. Examples of primary alcohols include ethanol, 1-propanol, and n-Butanol, 1-butanol. Methanol is also generally regarded as a primary alcohol, including by the 1911 edition of the Encyclopædia Britannica. See also * Alcohol (chemistry), Alcohol (especially Nomenclature section for discussion on Secondary and Tertiary alcohols.) * Oxidation of primary alcohols to carboxylic acids References Primary alcohols, {{organic-chem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diols
A diol is a chemical compound containing two hydroxyl groups ( groups). An aliphatic diol may also be called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified. They are used as protecting groups of carbonyl groups, making them essential in synthesis of organic chemistry. The most common industrial diol is ethylene glycol. Examples of diols in which the hydroxyl functional groups are more widely separated include 1,4-butanediol and propylene-1,3-diol, or beta propylene glycol, . Synthesis of classes of diols Geminal diols A geminal diol has two hydroxyl groups bonded to the same atom. These species arise by hydration of the carbonyl compounds. The hydration is usually unfavorable, but a notable exception is formaldehyde which, in water, exists in equilibrium with methanediol H2C(OH)2. Another example is (F3C)2C(OH)2, the hydrated form of hexafluoroacetone. Many gem-diols undergo further condensation to give dimer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentacyclic Compounds
A cyclic flower is a flower type formed out of a series of whorls; sets of identical organs attached around the axis at the same point. Most flowers consist of a single whorl of sepals termed a calyx; a single whorl of petals termed a corolla; one or more whorls of stamens (together termed the androecium); and a single whorl of carpels termed the gynoecium. This is a cyclic arrangement. Some flowers contain flower parts with a spiral arrangement. Such flowers are not cyclic. However in the common case of spirally arranged sepals on an otherwise cyclic flower, the term hemicyclic may be used. The suffix -cyclic is used to denote the number of whorls contained within a flower. The most common case is the pentacyclic flower, which contains five whorls: a calyx, a corolla, two whorls of stamens, and a single whorl of carpels. Another common case is the tetracyclic flower, which contains only one whorl of stamens, and therefore only four whorls in total. Tricyclic flowers also occur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isopropenyl Compounds
In organic chemistry, 1-propenyl (or simply propenyl) has the formula CH=CHCH3 and 2-propenyl (isopropenyl) has the formula CH2=C-CH3. These groups are found in many compounds. Propenyl compounds are Isomer , isomeric with allyl compounds, which have the formula CH2-CH=CH2. Chemicals with 1-propenyl groups *2-Chloropropylene, 2-chloropropylene *propenylbenzene (β-methylstyrene). Many phenylpropanoids and their derivatives feature derivatives of propenylbenzene: *Anethole *Asarone *Carpacin *Coniferyl alcohol *Isoeugenol *Isosafrole *Methyl isoeugenol *Pseudoisoeugenol Chemicals with 2-propenyl groups Isopropenyl acetate is a 2-propenyl ester, synthesizable from ketene. Several terpenes feature 2-propenyl substituents: *carvone *limonene See also * Propene * Functional group References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triterpenes
Triterpenes are a class of terpenes composed of six isoprene units with the molecular formula C30H48; they may also be thought of as consisting of three terpene units. Animals, plants and fungi all produce triterpenes, including squalene, the precursor to all steroids. Structures Triterpenes exist in a great variety of structures. Nearly 200 different skeletons have been identified. These skeletons may be broadly divided according to the number of rings present. In general pentacyclic structures (5 rings) tend to dominate. Squalene is biosynthesized through the head-to-head condensation of two farnesyl pyrophosphate units. This coupling converts a pair of C15 components into a C30 product. Squalene serves as precursor for the formation of many triterpenoids, including bacterial hopanoids and eukaryotic sterols. Triterpenoids By definition triterpenoids are triterpenes that possess heteroatoms, usually oxygen. The terms ''triterpene'' and ''triterpenoid'' often are used in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
