|
Orcinol
Orcinol is an organic compound with the formula CH3C6H3(OH)2. It occurs in many species of lichens including ''Roccella tinctoria'' and ''Lecanora''. Orcinol has been detected in the "toxic glue" of the ant species ''Camponotus saundersi''. It is a colorless solid. It is related to resorcinol, 1,3-C6H4(OH)2. Synthesis and reactions Orcinol was first prepared by dehydroacetic acid, a conversion that involved ring-opening of the pyrone to a triketone. This early experiment helped establish the rich condensation chemistry of polyketides. It can be obtained by fusing extract of aloes with potash, followed by acidification. It undergoes ''O''-methylation with dimethylsulfate. It is used in the production of the dye orcein and as a reagent in some chemical tests for pentoses, such as Bial's Test. It may be synthesized from toluene; more interesting is its production when acetone dicarboxylic ester is condensed with the aid of sodium. It crystallizes in colorless prisms with one m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resorcinol
Resorcinol (or resorcin) is a phenolic compound. It is an organic compound with the formula C6H4(OH)2. It is one of three isomeric benzenediols, the 1,3-isomer (or ''meta- (chemistry), meta''-isomer). Resorcinol crystallizes from benzene as colorless needles that are readily soluble in water, alcohol, and ether, but insoluble in chloroform and carbon disulfide. Production Resorcinol is produced in several steps from benzene, starting with dialkylation with propylene to give 1,3-Diisopropylbenzene, 1,3-diisopropylbenzene. Oxidation and Hock rearrangement of this disubstituted arene gives acetone and resorcinol. Resorcinol is a relatively inexpensive chemical. It is produced in only a very few locations around the world (as of 2010 only four commercial plants were known to be operative: in the United States, Germany, China, and Japan), and is the determining factor in the cost of Phenol formaldehyde resin, PRF adhesives. Production in the United States ended in 2017 with the cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bial's Test
Bial's test is a chemical test for the presence of pentoses originally developed for the diagnosis of pentosuria. It is named after Manfred Bial, a German physician. The components include orcinol, hydrochloric acid, and ferric chloride. A pentose, if present, will be dehydrated to form furfural which then reacts with orcinol to generate a colored substance. The solution will turn bluish and a precipitate may form. The solution shows two absorption bands, one in the red between Fraunhofer lines B and C and the other near the D line. An estimate of the relevant wavelengths can be made by referring to the Fraunhofer lines article. Composition Bial's reagent consists of 0.4 g orcinol, 200 ml of concentrated hydrochloric acid and 0.5 ml of a 10% solution of ferric chloride. Bial's test is used to distinguish pentoses from hexoses; this distinction is based on the color that develops in the presence of orcinol and iron (III) chloride. Furfural from pentoses gives a blue or green ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orcin Merck 820933
Orcinol is an organic compound with the formula CH3C6H3(OH)2. It occurs in many species of lichens including ''Roccella tinctoria'' and ''Lecanora''. Orcinol has been detected in the "toxic glue" of the ant species ''Camponotus saundersi''. It is a colorless solid. It is related to resorcinol, 1,3-C6H4(OH)2. Synthesis and reactions Orcinol was first prepared by dehydroacetic acid, a conversion that involved ring-opening of the pyrone to a triketone. This early experiment helped establish the rich condensation chemistry of polyketides. It can be obtained by fusing extract of aloes with potash, followed by acidification. It undergoes ''O''-methylation with dimethylsulfate. It is used in the production of the dye orcein and as a reagent in some chemical tests for pentoses, such as Bial's Test. It may be synthesized from toluene; more interesting is its production when acetone dicarboxylic ester is condensed with the aid of sodium. It crystallizes in colorless prisms with one mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescein
Fluorescein is an organic compound and dye based on the xanthene tricyclic structural motif, formally belonging to Triarylmethane dye, triarylmethine dyes family. It is available as a dark orange/red powder slightly soluble in water and alcohol. It is used as a fluorescent Flow tracer, tracer in many applications. The color of its aqueous solutions is green by reflection and orange by transmission (its spectral properties are dependent on pH of the solution), as can be noticed in spirit level, bubble levels, for example, in which fluorescein is added as a colorant to the Alcohol (chemistry), alcohol filling the tube in order to increase the visibility of the air bubble contained within. More concentrated solutions of fluorescein can even appear red (because under these conditions nearly all incident emission is re-absorbed by the solution). It is on the WHO Model List of Essential Medicines, World Health Organization's List of Essential Medicines. Uses Fluorescein sodium, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyketide
In organic chemistry, polyketides are a class of natural products derived from a Precursor (chemistry), precursor molecule consisting of a Polymer backbone, chain of alternating ketone (, or Carbonyl reduction, its reduced forms) and Methylene group, methylene () groups: . First studied in the early 20th century, discovery, biosynthesis, and application of polyketides has evolved. It is a large and diverse group of secondary metabolites caused by its complex biosynthesis which resembles that of fatty acid synthesis. Because of this diversity, polyketides can have various medicinal, agricultural, and industrial applications. Many polyketides are medicinal or exhibit acute toxicity. Biotechnology has enabled discovery of more naturally-occurring polyketides and evolution of new polyketides with novel or improved bioactivity. History Naturally produced polyketides by various plants and organisms have been used by humans since before studies on them began in the 19th and 20th century ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentose
In chemistry, a pentose is a monosaccharide (simple sugar) with five carbon atoms. The chemical formula of many pentoses is , and their molecular weight is 150.13 g/mol.-Ribose . PubChem compound webpage, accessed on 2010-02-06. Pentoses are very important in . Ribose is a constituent of , and the related molecule, deoxyribose, is a constituent of DNA. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Creosol
Creosol is a chemical compound with the molecular formula C8H10O2. It is one of the components of creosote. Compared with phenol, creosol is a less toxic disinfectant. Sources Sources of creosol include: * Coal tar creosote * Wood creosote * Reduction product of vanillin using zinc powder in strong hydrochloric acid ( Clemmensen reduction) * Found as glycosides in green vanilla beans * It is also found in tequila.Characterization of volatile compounds from ethnic Agave alcoholic beverages by gas chromatography-mass spectrometry. León-Rodríguez, A. de, Escalante-Minakata, P., Jiménez-García, M. I., Ordoñez-Acevedo, L. G., Flores Flores, J. L. and Barba de la Rosa, A. P., Food Technology and Biotechnology, 2008, Volume 46, Number 4, pages 448-455abstract) Reactions Creosol reacts with hydrogen halides to give a catechol. : See also * Vanillin Vanillin is an organic compound with the molecular formula . It is a phenolic aldehyde. Its functional groups include aldehyde, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beech
Beech (genus ''Fagus'') is a genus of deciduous trees in the family Fagaceae, native to subtropical (accessory forest element) and temperate (as dominant element of Mesophyte, mesophytic forests) Eurasia and North America. There are 14 accepted species in two distinct subgenera, ''Englerianae'' and ''Fagus''. The subgenus ''Englerianae'' is found only in East Asia, distinctive for its low branches, often made up of several major trunks with yellowish bark. The better known species of subgenus ''Fagus'' are native to Europe, western and eastern Asia and eastern North America. They are high-branching trees with tall, stout trunks and smooth silver-grey bark. The European beech ''Fagus sylvatica'' is the most commonly cultivated species, yielding a utility timber used for furniture construction, flooring and engineering purposes, in plywood, and household items. The timber can be used to build homes. Beechwood makes excellent firewood. Slats of washed beech wood are spread around ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isomer
In chemistry, isomers are molecules or polyatomic ions with identical molecular formula – that is, the same number of atoms of each element (chemistry), element – but distinct arrangements of atoms in space. ''Isomerism'' refers to the existence or possibility of isomers. Isomers do not necessarily share similar chemical property, chemical or physical property, physical properties. Two main forms of isomerism are structural isomerism, structural (or constitutional) isomerism, in which ''chemical bond, bonds'' between the atoms differ; and stereoisomerism (or spatial isomerism), in which the bonds are the same but the ''relative positions'' of the atoms differ. Isomeric relationships form a hierarchy. Two chemicals might be the same constitutional isomer, but upon deeper analysis be stereoisomers of each other. Two molecules that are the same stereoisomer as each other might be in different conformational forms or be different Isotopologue, isotopologues. The depth of analy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetone Dicarboxylic Ester
Acetone (2-propanone or dimethyl ketone) is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile, and flammable liquid with a characteristic pungent odor. Acetone is miscible with water and serves as an important organic solvent in industry, home, and laboratory. About 6.7 million tonnes were produced worldwide in 2010, mainly for use as a solvent and for production of methyl methacrylate and bisphenol A, which are precursors to widely used plastics.Acetone World Petrochemicals report, January 2010Stylianos Sifniades, Alan B. Levy, "Acetone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. It is a common building block in |
Orcein
Orcein, also called archil, orchil, lacmus and C.I. Natural Red 28, is any dye extracted from several species of lichen, commonly known as "orchella weeds", found in various parts of the world. A major source is the archil lichen, '' Roccella tinctoria''. Orcinol is extracted from such lichens. It is then converted to orcein by ammonia and air. In traditional dye-making methods, urine was used as the ammonia source. If the conversion is carried out in the presence of potassium carbonate, calcium hydroxide, and calcium sulfate (in the form of potash, lime, and gypsum in traditional dye-making methods), the result is litmus, a more complex molecule. The manufacture was described by Cocq in 1812 and in the UK in 1874. Edmund Roberts noted orchilla as a principal export of the Cape Verde islands, superior to the same kind of "moss" found in Italy or the Canary Islands, that in 1832 was yielding an annual revenue of $200,000. Commercial archil is either a powder (called cudbear) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
