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Carpanone
Carpanone is a naturally occurring lignan-type natural product most widely known for the remarkably complex way nature prepares it, and the similarly remarkable success that an early chemistry group, that of Orville L. Chapman, had at mimicking nature's pathway.C.W. Lindsley, C.R. Hopkins & G.A. Sulikowski, 2011, Biomimetic synthesis of lignans, In "Biomimetic Organic Synthesis" (E. Poupon & B. Nay, Eds.), Weinheim: Wiley-VCH, , se accessed 4 June 2014.O.L. Chapman, M.R. Engel, J.P. Springer & J.C. Clardy, 1971, Total synthesis of carpanone, ''J. Am. Chem. Soc.'' 93:6697–6698. Carpanone is an organic compound first isolated from the carpano trees (''Cinnamomum sp.'') of Bougainville Island by Brophy and coworkers, trees from which the natural product derives its name.F. Liron, F. Fontana, J.-O. Zirimwabagabo, G. Prestat, J. Rajabi, C. La Rosa & G. Poli, 2009, A New Cross-Coupling-Based Synthesis of Carpanone, Org. Lett., 11(19):4378–4381, DOI: 10.1021/ol9017326, see o acces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpanone Synthesis
Carpanone is a naturally occurring lignan-type natural product most widely known for the remarkably complex way nature prepares it, and the similarly remarkable success that an early chemistry group, that of Orville L. Chapman, had at mimicking nature's pathway.C.W. Lindsley, C.R. Hopkins & G.A. Sulikowski, 2011, Biomimetic synthesis of lignans, In "Biomimetic Organic Synthesis" (E. Poupon & B. Nay, Eds.), Weinheim: Wiley-VCH, , se accessed 4 June 2014.O.L. Chapman, M.R. Engel, J.P. Springer & J.C. Clardy, 1971, Total synthesis of carpanone, ''J. Am. Chem. Soc.'' 93:6697–6698. Carpanone is an organic compound first isolated from the carpano trees (''Cinnamomum sp.'') of Bougainville Island by Brophy and coworkers, trees from which the natural product derives its name.F. Liron, F. Fontana, J.-O. Zirimwabagabo, G. Prestat, J. Rajabi, C. La Rosa & G. Poli, 2009, A New Cross-Coupling-Based Synthesis of Carpanone, Org. Lett., 11(19):4378–4381, DOI: 10.1021/ol9017326, see o acces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomimetic Synthesis
Biomimetic synthesis is an area of organic chemical synthesis that is specifically biologically inspired. The term encompasses both the testing of a "biogenetic hypothesis" (''conjectured'' course of a biosynthesis in nature) through execution of a series of reactions designed to parallel the proposed biosynthesis, as well as programs of study where a synthetic reaction or reactions aimed at a desired synthetic goal are designed to mimic one or more ''known'' enzymic transformations of an established biosynthetic pathway. The earliest generally cited example of a biomimetic synthesis is Sir Robert Robinson's organic synthesis of the alkaloid tropinone. A more recent example is E.J. Corey's carbenium-mediated cyclization of an engineered linear polyene to provide a tetracyclic steroid ring system, which built upon studies of cationic cyclizations of linear polyenes by the Albert Eschenmoser and Gilbert Stork, and the extensive studies of the W.S. Johnson to define the requireme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpacin
Carpacin is a naturally occurring organic compound first isolated from the Carpano tree (an unidentified ''Cinnamomum'' species of the family Lauraceae which is native to Bougainville Island), from which it derives its name. It is also found in essential oils of the genus ''Crowea''. Carpacin is a biosynthetic precursor of the more complex lignan-dimer, carpanone. It is classified as a phenylpropanoid. Carpacin has been prepared synthetically from sesamol and has been studied for potential use as an insecticide and inhibitor of carcinogenesis Carcinogenesis, also called oncogenesis or tumorigenesis, is the formation of a cancer, whereby normal cells are transformed into cancer cells. The process is characterized by changes at the cellular, genetic, and epigenetic levels and abnor .... References {{Phenylpropene Phenylpropenes O-methylated phenylpropanoids Benzodioxoles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpacin
Carpacin is a naturally occurring organic compound first isolated from the Carpano tree (an unidentified ''Cinnamomum'' species of the family Lauraceae which is native to Bougainville Island), from which it derives its name. It is also found in essential oils of the genus ''Crowea''. Carpacin is a biosynthetic precursor of the more complex lignan-dimer, carpanone. It is classified as a phenylpropanoid. Carpacin has been prepared synthetically from sesamol and has been studied for potential use as an insecticide and inhibitor of carcinogenesis Carcinogenesis, also called oncogenesis or tumorigenesis, is the formation of a cancer, whereby normal cells are transformed into cancer cells. The process is characterized by changes at the cellular, genetic, and epigenetic levels and abnor .... References {{Phenylpropene Phenylpropenes O-methylated phenylpropanoids Benzodioxoles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lignan
The lignans are a large group of low molecular weight polyphenols found in plants, particularly seeds, whole grains, and vegetables. The name derives from the Latin word for "wood". Lignans are precursors to phytoestrogens. They may play a role as antifeedants in the defense of seeds and plants against herbivores. Biosynthesis and metabolism Lignans and lignin differ in their molecular weight, the former being small and soluble in water, the latter being high polymers that are undigestable. Both are polyphenolic substances derived by oxidative coupling of monolignols. Thus, most lignans feature a C18 cores, resulting from the dimerization of C9 precursors. The coupling of the lignols occurs at C8. Eight classes of lignans are: "furofuran, furan, dibenzylbutane, dibenzylbutyrolactone, aryltetralin, arylnaphthalene, dibenzocyclooctadiene, and dibenzylbutyrolactol." Many lignans are metabolized by mammalian gut microflora, producing so-called enterolignans. Food sources Flax s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkene
In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, and Biological Chemistry'. 1232 pages. Two general types of monoalkenes are distinguished: terminal and internal. Also called α-olefins, terminal alkenes are more useful. However, the International Union of Pure and Applied Chemistry (IUPAC) recommends using the name "alkene" only for acyclic hydrocarbons with just one double bond; alkadiene, alkatriene, etc., or polyene for acyclic hydrocarbons with two or more double bonds; cycloalkene, cycloalkadiene, etc. for cyclic ones; and "olefin" for the general class – cyclic or acyclic, with one or more double bonds. Acyclic alkenes, with only one double bond and no other functional groups (also known as mono-enes) form a homologous series of hydrocarbons with the general formula with '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allyl
In organic chemistry, an allyl group is a substituent with the structural formula , where R is the rest of the molecule. It consists of a methylene bridge () attached to a vinyl group (). The name is derived from the scientific name for garlic, . In 1844, Theodor Wertheim isolated an allyl derivative from garlic oil and named it "". The term allyl applies to many compounds related to , some of which are of practical or of everyday importance, for example, allyl chloride. Allylation is any chemical reaction that adds an allyl group to a substrate. Nomenclature A site adjacent to the unsaturated carbon atom is called the allylic position or allylic site. A group attached at this site is sometimes described as allylic. Thus, "has an allylic hydroxyl group". Allylic C−H bonds are about 15% weaker than the C−H bonds in ordinary sp3 carbon centers and are thus more reactive. Benzylic and allylic are related in terms of structure, bond strength, and reactivity. Other re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sesamol
Sesamol is a natural organic compound which is a component of sesame seeds and sesame oil, with anti- inflammatory, antioxidant, antidepressant and neuroprotective properties. It is a white crystalline solid that is a derivative of phenol. It is sparingly soluble in water, but miscible with most oils. It can be produced by organic synthesis from heliotropine. Sesamol has been found to be an antioxidant that may prevent the spoilage of oils. It also may prevent the spoilage of oils by acting as an antifungal. It can be used in the synthesis of paroxetine. Sesamol's molecular targets and mechanism of action, at least for its antidepressant-like effects, is found to be through the brain nerve growth factor (NGF) and endocannabinoid signalling under the regulatory drive of the CB1 receptors. Alexander Shulgin used sesamol in his book PiHKAL to make MMDA-2 MMDA-2 (2-methoxy-4,5-methylenedioxyamphetamine) is a psychedelic drug of the amphetamine class. It is closely relate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claisen Rearrangement
The Claisen rearrangement is a powerful carbon–carbon bond-forming chemical reaction discovered by Rainer Ludwig Claisen. The heating of an allyl vinyl ether will initiate a ,3sigmatropic rearrangement to give a γ,δ-unsaturated carbonyl, driven by exergonically favored carbonyl CO bond formation (ΔΔHf = -327kcalmol−1). Mechanism The Claisen rearrangement is an exothermic, concerted (bond cleavage and recombination) pericyclic reaction. Woodward–Hoffmann rules show a suprafacial, stereospecific reaction pathway. The kinetics are of the first order and the whole transformation proceeds through a highly ordered cyclic transition state and is intramolecular. Crossover experiments eliminate the possibility of the rearrangement occurring via an intermolecular reaction mechanism and are consistent with an intramolecular process. There are substantial solvent effects observed in the Claisen rearrangement, where polar solvents tend to accelerate the reaction to a greater e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinone Methide
A quinone methide is a type of conjugated organic compound that contain a cyclohexadiene with a carbonyl and an exocyclic methylidene or extended alkene unit. It is analogous to a quinone, but having one of the double bonded oxygens replaced with a carbon. The carbonyl and methylidene are usually oriented either ortho or para to each other. There are some examples of transient synthetic meta quinone methides. Properties Quinone methides are cross-conjugated rather than aromatic. Nucleophilic addition at the exo-cyclic double bond will result in rearomatisation, making such reactions highly favourable. As a result, quinone methides are excellent, electrophilic Michael acceptors, react quickly with nucleophiles and can be easily reduced. They are able to act as radical scavengers via a similar process, a behaviour exploited by certain polymerisation inhibitors. Quinone methides are more polar than quinones, and therefore more chemically reactive. Simple unhindered quinone methide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hit To Lead
Hit to lead (H2L) also known as lead generation is a stage in early drug discovery where small molecule hits from a high-throughput screening, high throughput screen (HTS) are evaluated and undergo limited optimization to identify promising lead compounds. These lead compounds undergo more extensive optimization in a subsequent step of drug discovery called lead optimization (LO). The drug discovery process generally follows the following path that includes a hit to lead stage: * Target validation (TV) → Assay development → High-throughput screening (HTS) → Hit to lead (H2L) → #Lead optimization phase, Lead optimization (LO) → Preclinical development → Drug development#Clinical phase, Clinical development The hit to lead stage starts with confirmation and evaluation of the initial screening hits and is followed by synthesis of structural analog, analogs (hit expansion). Typically the initial screening hits display binding affinity, binding affinities for their biologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
