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Pentadiene Molecular Orbitals
In organic chemistry, pentadiene is any hydrocarbon with an open chain of five carbons, connected by two single bonds and two double bonds. All those compounds have the same molecular formula . The inventory of pentadienes include: * 1,2-pentadiene, or ethyl allene, .James R. Durig, Stephen Bell, Gamil A. Guirgis (1996): "Infrared and Raman spectra, conformational stability, ab initio calculations and vibrational assignment for 1,2-pentadiene (ethyl allene)". ''Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy'', volume 52, issue 14, pages 1843-1859. It and 2,3-pentadiene are the least common isomers of pentadiene. * 1,3-pentadiene, with two isomers:Aldo Priola, Sebastiano Cesca, Giuseppe Ferraris, and Mario Bruzzone (1975): "Relative reactivity of cis‐ and trans‐1,3‐pentadiene in the cationic copolymerization with isobutene". ''Die Makromolekulare Chemie'', volume 176, issue 7, pages 1969-1981. S. Boue and Rangaswamy Srinivasan (1970): "Differences in rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Chemistry
Organic chemistry is a subdiscipline within chemistry involving the science, scientific study of the structure, properties, and reactions of organic compounds and organic matter, organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J.; Greeves, N. and Warren, S. (2012) ''Organic Chemistry''. Oxford University Press. pp. 1–15. . Study of structure determines their structural formula. Study of properties includes Physical property, physical and Chemical property, chemical properties, and evaluation of Reactivity (chemistry), chemical reactivity to understand their behavior. The study of organic reactions includes the organic synthesis, chemical synthesis of natural products, drugs, and polymers, and study of individual organic molecules in the laboratory and via theoretical (in silico) study. The range of chemicals studied chemistry includes hydrocarbons (compounds containing only carbon and hydrogen) as well as compounds based on carbon, but a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyunsaturated Fatty Acid
In biochemistry and nutrition, a polyunsaturated fat is a fat that contains a polyunsaturated fatty acid (abbreviated PUFA), which is a subclass of fatty acid characterized by a backbone with two or more carbon–carbon double bonds. Some polyunsaturated fatty acids are essentials. Polyunsaturated fatty acids are precursors to and are derived from polyunsaturated fats, which include drying oils. Nomenclature The position of the carbon-carbon double bonds in carboxylic acid chains in fats is designated by Greek letters. The carbon atom closest to the carboxyl group is the ''alpha'' carbon, the next carbon is the ''beta'' carbon and so on. In fatty acids the carbon atom of the methyl group at the end of the hydrocarbon chain is called the ''omega'' carbon because ''omega'' is the last letter of the Greek alphabet. Omega-3 fatty acids have a double bond three carbons away from the methyl carbon, whereas omega-6 fatty acids have a double bond six carbons away from the methyl ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostacyclin
Prostacyclin (also called prostaglandin I2 or PGI2) is a prostaglandin member of the eicosanoid family of lipid molecules. It inhibits platelet activation and is also an effective vasodilator. When used as a drug, it is also known as epoprostenol. The terms are sometimes used interchangeably. Function Prostacyclin chiefly prevents formation of the platelet plug involved in primary hemostasis (a part of blood clot formation). It does this by inhibiting platelet activation. It is also an effective vasodilator. Prostacyclin's interactions contrast with those of thromboxane (TXA2), another eicosanoid. Both molecules are derived from arachidonic acid, and work together with opposite platelet aggregatory effects. These strongly suggest a mechanism of cardiovascular homeostasis between these two hormones in relation to vascular damage. Medical uses It is used to treat pulmonary arterial hypertension (PAH), pulmonary fibrosis, as well as atherosclerosis. Prostacyclins are given to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostaglandin
Prostaglandins (PG) are a group of physiology, physiologically active lipid compounds called eicosanoids that have diverse hormone-like effects in animals. Prostaglandins have been found in almost every Tissue (biology), tissue in humans and other animals. They are derived enzymatically from the fatty acid arachidonic acid. Every prostaglandin contains 20 carbon atoms, including a carbon ring, 5-carbon ring. They are a subclass of eicosanoids and of the prostanoid class of fatty acid derivatives. The structural differences between prostaglandins account for their different biological activities. A given prostaglandin may have different and even opposite effects in different tissues in some cases. The ability of the same prostaglandin to stimulate a reaction in one tissue and inhibit the same reaction in another tissue is determined by the type of receptor (biochemistry), receptor to which the prostaglandin binds. They act as autocrine or paracrine factors with their target cells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thromboxane
Thromboxane is a member of the family of lipids known as eicosanoids. The two major thromboxanes are thromboxane A2 and thromboxane B2. The distinguishing feature of thromboxanes is a 6-membered ether-containing ring. Thromboxane is named for its role in blood clot formation (thrombosis). Production Thromboxane-A synthase, an enzyme found in platelets, converts the arachidonic acid derivative prostaglandin H2 to thromboxane. People with asthma tend to have increased thromboxane production, and analogs of thromboxane act as bronchoconstrictors in patients with asthma. Mechanism Thromboxane acts by binding to any of the thromboxane receptors, G-protein-coupled receptors coupled to the G protein Gq. Functions Thromboxane is a vasoconstrictor and a potent hypertensive agent, and it facilitates platelet aggregation. It is in homeostatic balance in the circulatory system with prostacyclin, a related compound. The mechanism of secretion of thromboxanes from platelets is s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostanoid
In molecular biology, prostanoids are active lipid mediators that regulate inflammatory response. Prostanoids are a subclass of eicosanoids consisting of the prostaglandins (mediators of inflammatory and anaphylactic reactions), the thromboxanes (mediators of vasoconstriction), and the prostacyclins (active in the resolution phase of inflammation). Prostanoids are seen to target NSAIDS which allow for therapeutic potential. Prostanoids are present within areas of the body such as the gastrointestinal tract, urinary tract, respiratory and cardiovascular systems, reproductive tract and vascular system. Prostanoids can even be seen with aid to the water and ion transportation within cells. History Prostanoids were discovered through biological research studies conducted in the 1930s. The first discovery was seen through semen by a Swedish Physiologist Ulf von Euler, who assumed they originated from the prostate. After intensive study throughout the 1960-1970s Sune K. Bergstr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme, pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclooxygenase
Cyclooxygenase (COX), officially known as prostaglandin-endoperoxide synthase (PTGS), is an enzyme (specifically, a family of isozymes, ) that is responsible for biosynthesis of prostanoids, including thromboxane and prostaglandins such as prostacyclin, from arachidonic acid. A member of the animal-type heme peroxidase family, it is also known as prostaglandin G/H synthase. The specific reaction catalyzed is the conversion from arachidonic acid to prostaglandin H2 via a short-living prostaglandin G2 intermediate. Pharmaceutical inhibition of COX can provide relief from the symptoms of inflammation and pain. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen, exert their effects through inhibition of COX. Those that are specific to the COX-2 isozyme are called COX-2 inhibitors. The active metabolite ( AM404) of paracetamol is a COX inhibitor, a fact to which some or all of its therapeutic effect has been attributed. In medicine, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antifeedant
Antifeedants are organic compounds produced by plants to repel herbivores through distaste or toxicity. These chemical compounds are typically classified as secondary metabolites in that they are not essential for the metabolism of the plant, but instead confer longevity. Antifeedants exhibit a wide range of activities and chemical structures as biopesticides. Examples include rosin, which inhibits attack on trees, and many alkaloids, which are highly toxic to specific insect species, such as quassinoids (extracts from ''Quassia'' trees) against the diamondback moth ('' Plutela xylostella''). ''Samadera indica'' also has quassinoids used for insect antifeedant uses. History "Plant-derived insecticides (e.g., rotenone, veratridines, pyrethrins, and nicotine) have been used for insect control since antiquity." The active ingredients in these plants have been purified and modified. For example, variations on pyrethrin have spawned a large number of synthetic insecticides calle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf Aldehyde
''cis''-3-Hexenal, also known as (''Z'')-3-hexenal and leaf aldehyde, is an organic compound with the formula CH3CH2CH=CHCH2CHO. It is classified as an unsaturated aldehyde. It is a colorless liquid and an aroma compound with an intense odor of freshly cut grass and leaves. Occurrence It is one of the major volatile compounds in ripe tomatoes, although it tends to isomerize into the conjugated ''trans''-2-hexenal. It is produced in small amounts by most plants and it acts as an attractant to many predatory insects. It is also a pheromone in many insect species. See also * ''cis''-3-Hexen-1-ol has a similar but weaker odor and is used in flavors and perfumes. * 1-Hexanol, another volatile organic compound Volatile organic compounds (VOCs) are organic compounds that have a high vapor pressure at room temperature. They are common and exist in a variety of settings and products, not limited to Indoor mold, house mold, Upholstery, upholstered furnitur ..., also considered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Divinylether Fatty Acids
Divinylether fatty acids contain a fatty acid chemically combined with a doubly unsaturated carbon chain linked by an oxygen atom (ether). Fatty acid hydroperoxides generated by plant lipoxygenases from linoleic and linolenic acids are known to serve as substrates for a divinyl ether synthase which produces divinyl ether fatty acids. Divinyl ethers were detected only within the plant kingdom. The discovery of that class of compounds dates to 1972, when the structures of two ether C18 fatty acids generated by homogenates of the potato tuber were described. These compounds, named colneleic acid (from linoleic acid) and colnelenicacid (from linolenic acid), could be also produced in potato leaves and tomato roots by rearrangement of 9-hydroperoxides. Isomers of colneleic acid and colnelenic acid were isolated from homogenates of leaves of ''Clematis vitalba'' (Ranunculaceae). Similarly, 13-lipoxygenase-generated hydroperoxides serve as precursor of other divinyl ether fatty ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jasmonate
Jasmonate (JA) and its derivatives are lipid-based plant hormones that regulate a wide range of processes in plants, ranging from growth and photosynthesis to reproductive development. In particular, JAs are critical for plant defense against herbivory and plant responses to poor environmental conditions and other kinds of abiotic and biotic challenges. Some JAs can also be released as volatile organic compounds (VOCs) to permit communication between plants in anticipation of mutual dangers. History The isolation of methyl jasmonate (MeJA) from jasmine oil derived from '' Jasminum grandiflorum'' led to the discovery of the molecular structure of jasmonates and their name in 1962 while jasmonic acid itself was isolated from '' Lasiodiplodia theobromae'' by Alderidge et al in 1971. Biosynthesis Biosynthesis is reviewed by Acosta and Farmer 2010, Wasternack and Hause 2013, and Wasternack and Song 2017. Jasmonates (JA) are oxylipins, i.e. derivatives of oxygenated fatty acid. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
