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Chalcone
Chalcone is the organic compound C6H5C(O)CH=CHC6H5. It is an α,β-unsaturated ketone. A variety of important biological compounds are known collectively as chalcones or chalconoids. Chemical properties Chalcones have two absorption maxima at 280 nm and 340 nm. Synthesis Chalcone is usually prepared by an aldol condensation between benzaldehyde and acetophenone. : This reaction, which can be carried out without any solvent, is so reliable that it is used in as an example of green chemistry in undergraduate education. Biosynthesis Chalcones and chalconoids are synthesized in plants as secondary metabolites. The enzyme chalcone synthase, a type III polyketide synthase, is responsible for the biosynthesis of these compounds. The enzyme is found in all "higher" (vascular) and several "lower" ( non-vascular) plants. Potential pharmacology Chalcones and their derivatives demonstrate a wide range of biological activities including anti-inflammation. Some 2′-amino ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chalcone Synthase
Chalcone synthase or naringenin-chalcone synthase (CHS) is an enzyme ubiquitous to higher plants and belongs to a family of polyketide synthase enzymes (PKS) known as type III PKS. Type III PKSs are associated with the production of chalcones, a class of organic compounds found mainly in plants as natural defense mechanisms and as synthetic intermediates. CHS was the first type III PKS to be discovered. It is the first committed enzyme in flavonoid biosynthesis. The enzyme catalyzes the conversion of 4-coumaroyl-CoA and malonyl-CoA to naringenin chalcone. Function CHS catalysis serves as the initial step for flavonoid biosynthesis. Flavonoids are important plant secondary metabolites that serve various functions in higher plants. These include pigmentation, UV protection, fertility, antifungal defense and the recruitment of nitrogen-fixing bacteria. CHS is believed to act as a central hub for the enzymes involved in the flavonoid pathway. Studies have shown that these enzyme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chalcone Preparation
Chalcone is the organic compound C6H5C(O)CH=CHC6H5. It is an α,β-unsaturated ketone. A variety of important biological compounds are known collectively as chalcones or chalconoids. Chemical properties Chalcones have two absorption maxima at 280 nm and 340 nm. Synthesis Chalcone is usually prepared by an aldol condensation between benzaldehyde and acetophenone. : This reaction, which can be carried out without any solvent, is so reliable that it is used in as an example of green chemistry in undergraduate education. Biosynthesis Chalcones and chalconoids are synthesized in plants as secondary metabolites. The enzyme chalcone synthase, a type III polyketide synthase, is responsible for the biosynthesis of these compounds. The enzyme is found in all "higher" (vascular) and several "lower" ( non-vascular) plants. Potential pharmacology Chalcones and their derivatives demonstrate a wide range of biological activities including anti-inflammation. Some 2′-amino ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chalconoids
Chalconoids Greek: χαλκός ''khalkós'', "copper", due to its color), also known as ''chalcones'', are natural phenols related to chalcone. They form the central core for a variety of important biological compounds. They show antibacterial, antifungal, antitumor and anti-inflammatory properties. Some chalconoids demonstrated the ability to block voltage-dependent potassium channels. Chalcones are also natural aromatase inhibitors. Chalcones are aromatic ketones with two phenyl rings that are also intermediates in the synthesis of many biological compounds. The closure of hydroxychalcones causes the formation of the flavonoid structure. Flavonoids are substances in the plant secondary metabolism with an array of biological activities. Chalconoids are also intermediates in the Auwers synthesis of flavones. Chemical properties Biosynthesis and metabolism Chalcone synthase is an enzyme responsible for the production of chalconoids in plants. Chalcone isomerase is responsi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chalconoid
Chalconoids Greek: χαλκός ''khalkós'', "copper", due to its color), also known as ''chalcones'', are natural phenols related to chalcone. They form the central core for a variety of important biological compounds. They show antibacterial, antifungal, antitumor and anti-inflammatory properties. Some chalconoids demonstrated the ability to block voltage-dependent potassium channels. Chalcones are also natural aromatase inhibitors. Chalcones are aromatic ketones with two phenyl rings that are also intermediates in the synthesis of many biological compounds. The closure of hydroxychalcones causes the formation of the flavonoid structure. Flavonoids are substances in the plant secondary metabolism with an array of biological activities. Chalconoids are also intermediates in the Auwers synthesis of flavones. Chemical properties Biosynthesis and metabolism Chalcone synthase is an enzyme responsible for the production of chalconoids in plants. Chalcone isomerase is responsi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chalconoids
Chalconoids Greek: χαλκός ''khalkós'', "copper", due to its color), also known as ''chalcones'', are natural phenols related to chalcone. They form the central core for a variety of important biological compounds. They show antibacterial, antifungal, antitumor and anti-inflammatory properties. Some chalconoids demonstrated the ability to block voltage-dependent potassium channels. Chalcones are also natural aromatase inhibitors. Chalcones are aromatic ketones with two phenyl rings that are also intermediates in the synthesis of many biological compounds. The closure of hydroxychalcones causes the formation of the flavonoid structure. Flavonoids are substances in the plant secondary metabolism with an array of biological activities. Chalconoids are also intermediates in the Auwers synthesis of flavones. Chemical properties Biosynthesis and metabolism Chalcone synthase is an enzyme responsible for the production of chalconoids in plants. Chalcone isomerase is responsi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juliá–Colonna Epoxidation
The Juliá–Colonna epoxidation is an asymmetric poly-leucine catalyzed nucleophilic epoxidation of electron deficient olefins in a triphasic system. The reaction was reported by Sebastian Juliá at the Chemical Institute of Sarriá in 1980, with further elaboration by both Juliá and Stefano Colonna (Istituto di Chimica Industriale dell'Università, Milan, Italy). : In the original triphasic protocol, the chalcone substrate is soluble in the organic phase, generally toluene or carbon tetrachloride. The alkaline hydrogen peroxide oxidant is soluble primarily in the aqueous phase, and the reaction occurs at the insoluble polymer layer at the interface of the two phases. Alternative biphasic and monophasic protocols have been developed with increased substrate accessibility and reaction rate. The efficient enantioselective catalytic epoxidation under mild conditions is of great synthetic utility. Not only are epoxides effective synthons for a range of transformations, they hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyketide Synthase
Polyketides are a class of natural products derived from a precursor molecule consisting of a chain of alternating ketone (or reduced forms of a ketone) and methylene groups: (-CO-CH2-). 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. In 1893, J. Norman Collie synthesized detectable amounts of orcinol by heating dehy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society (professional association) in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 34,000 in the UK and a further 8,000 abroad. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Privileged Scaffold
In biochemistry and pharmacology, a ligand is a substance that forms a complex with a biomolecule to serve a biological purpose. The etymology stems from ''ligare'', which means 'to bind'. In protein-ligand binding, the ligand is usually a molecule which produces a signal by binding to a site on a target protein. The binding typically results in a change of conformational isomerism (conformation) of the target protein. In DNA-ligand binding studies, the ligand can be a small molecule, ion, or protein which binds to the DNA double helix. The relationship between ligand and binding partner is a function of charge, hydrophobicity, and molecular structure. Binding occurs by intermolecular forces, such as ionic bonds, hydrogen bonds and Van der Waals forces. The association or docking is actually reversible through dissociation. Measurably irreversible covalent bonding between a ligand and target molecule is atypical in biological systems. In contrast to the definition of li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medicinal Chemistry
Medicinal or pharmaceutical chemistry is a scientific discipline at the intersection of chemistry and pharmacy involved with designing and developing pharmaceutical drugs. Medicinal chemistry involves the identification, synthesis and development of new chemical entities suitable for therapeutic use. It also includes the study of existing drugs, their biological properties, and their quantitative structure-activity relationships (QSAR). Medicinal chemistry is a highly interdisciplinary science combining organic chemistry with biochemistry, computational chemistry, pharmacology, molecular biology, statistics, and physical chemistry. Compounds used as medicines are most often organic compounds, which are often divided into the broad classes of small organic molecules (e.g., atorvastatin, fluticasone, clopidogrel) and "biologics" (infliximab, erythropoietin, insulin glargine), the latter of which are most often medicinal preparations of proteins (natural and recombinant ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-vascular Plant
Non-vascular plants are plants without a vascular system consisting of xylem and phloem. Instead, they may possess simpler tissues that have specialized functions for the internal transport of water. Non-vascular plants include two distantly related groups: * Bryophytes, an informal group that taxonomists treat as three separate land-plant divisions, namely: Bryophyta (mosses), Marchantiophyta (liverworts), and Anthocerotophyta (hornworts). In all bryophytes, the primary plants are the haploid gametophytes, with the only diploid portion being the attached sporophyte, consisting of a stalk and sporangium. Because these plants lack lignified water-conducting tissues, they can't become as tall as most vascular plants. * Algae, especially green algae. The algae consist of several unrelated groups. Only the groups included in the Viridiplantae are still considered relatives of land plants. These groups are sometimes called "lower plants", referring to their status as the earliest pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vascular Plant
Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They also have a specialized non-lignified tissue (the phloem) to conduct products of photosynthesis. Vascular plants include the clubmosses, horsetails, ferns, gymnosperms (including conifers), and angiosperms (flowering plants). Scientific names for the group include Tracheophyta, Tracheobionta and Equisetopsida ''sensu lato''. Some early land plants (the rhyniophytes) had less developed vascular tissue; the term eutracheophyte has been used for all other vascular plants, including all living ones. Historically, vascular plants were known as "higher plants", as it was believed that they were further evolved than other plants due to being more complex organisms. However, this is an antiquated remnant of the obsolete scala naturae, and the term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
