HOME



picture info

Chalcones
Chalconoids (Greek: χαλκός ''khalkós'', "copper", due to its color), also known as chalcones, are natural phenols derived from 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 hydroxy chalcones causes the formation of the flavonoid structure. Flavonoids are substances in the plant's secondary metabolism with an array of biological activities. Chalconoids are also intermediating in the Auwers synthesis of flavones. Biosynthesis and metabolism Chalcone synthase is an enzyme responsible for the production of chalconoids in plants. Chalcone isomerase is responsible for their conv ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




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. They are widely known bioactive substances, fluorescent materials, and chemical intermediates. Chemical properties Chalcones have two absorption maxima at 280 nm and 340 nm. 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. Laboratory 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 often given as an example of green chemistry in undergraduate education. Potential pharmacology Chalcones and thei ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Dihydrochalcone
Dihydrochalcone (DHC) is the organic compound with the formula C6H5C(O)(CH2)2C6H5. It is the reduced derivative of chalcone (C6H5C(O)(CH)2C6H5). It is a white solid that is soluble in many organic solvents. Dihydrochalcone per se is often minor significance, but some derivatives occur in nature and have attracted attention as drugs. Natural dihydrochalcones left, Neohesperidin dihydrochalcone is a commercial artificial sweetener that features the dihydrochalcone substituent. * Aspalathin, a C-linked dihydrochalcone glucoside found in rooibos, a common herbal tea * Naringin dihydrochalcone, an artificial sweetener derived from naringin * Neohesperidin dihydrochalcone, an artificial sweetener derived from citrus * Nothofagin, a C-linked phloretin glucoside found in rooibos * Phloretin Phloretin is a dihydrochalcone, a type of natural phenol. It can be found in apple tree leaves and the Manchurian apricot. Metabolism In rats, ingested phlorizin is converted into phloreti ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Flavonoid Biosynthesis
Flavonoids are synthesized by the phenylpropanoid metabolic pathway in which the amino acid phenylalanine is used to produce 4-coumaroyl-CoA. This can be combined with malonyl-CoA to yield the true backbone of flavonoids, a group of compounds called chalcones, which contain two phenyl rings. Conjugate ring-closure of chalcones results in the familiar form of flavonoids, the three-ringed structure of a flavone. The metabolic pathway continues through a series of enzymatic modifications to yield flavanones → dihydroflavonols → anthocyanins. Along this pathway, many products can be formed, including the flavonols, flavan-3-ols, proanthocyanidins (tannins) and a host of other various polyphenolics. Flavanoids can possess chiral carbons. Methods of analysis should take this element into account especially regarding bioactivity or enzyme stereospecificity. Enzymes The biosynthesis of flavonoids involves several enzymes. * Anthocyanidin reductase * Chalcone isomerase * D ...
[...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 enzymes i ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Aurones
An aurone is a heterocyclic chemical compound, which is a type of flavonoid. There are two isomers of the molecule, with (''E'')- and (''Z'')-configurations. The molecule contains a benzofuran element associated with a benzylidene linked in position 2. In aurone, a chalconoid, chalcone-like group is closed into a 5-membered ring instead of the 6-membered ring more typical of flavonoids. Aurone derivatives Aurone forms the core for a family of derivatives which are known collectively as aurones. Aurones are plant flavonoids that provide yellow color to the flowers of some popular ornamental plants, such as Antirrhinum, snapdragon and cosmos (plant), cosmos. Aurones including 4'-chloro-2-hydroxyaurone (C15H11O3Cl) and 4'-chloroaurone (C15H9O2Cl) can also be found in the brown alga ''Spatoglossum variabile''. Most aurones are in a (''Z'')-configuration, which is the more stable configuration according to Austin Model 1 computation. But there are also some in the (''E'')-configur ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Naringenin Chalcone
Naringenin chalcone is a common chalconoid (or chalcone, not to be confused with the compound chalcone). It is synthesized from 4-coumaroyl-CoA and malonyl-CoA by chalcone synthase (CHS), a key enzyme in the phenylpropanoid pathway. Naringenin chalcone can spontaneously cyclize to naringenin (a flavanone). In plant cells, this process is catalyzed by chalcone isomerase In enzymology, a chalcone isomerase () is an enzyme that catalyzes the chemical reaction :a chalcone \rightleftharpoons a flavanone Hence, this enzyme has one substrate, a chalcone, and one product, a flavanone. This enzyme belongs to the fam .... References Chalconoids {{organic-compound-stub ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Coenzyme A
Coenzyme A (CoA, SHCoA, CoASH) is a coenzyme, notable for its role in the Fatty acid metabolism#Synthesis, synthesis and Fatty acid metabolism#.CE.B2-Oxidation, oxidation of fatty acids, and the oxidation of pyruvic acid, pyruvate in the citric acid cycle. All genomes sequenced to date encode enzymes that use coenzyme A as a Substrate (chemistry), substrate, and around 4% of cellular enzymes use it (or a thioester) as a substrate. In humans, CoA biosynthesis requires cysteine, pantothenic acid, pantothenate (vitamin B5), and adenosine triphosphate (ATP). In acetyl-CoA, its acetyl form, coenzyme A is a highly versatile molecule, serving metabolic functions in both the Anabolism, anabolic and Catabolism, catabolic pathways. Acetyl-CoA is utilised in the post-translational regulation and allosteric regulation of pyruvate dehydrogenase and carboxylase to maintain and support the partition of Pyruvic acid, pyruvate synthesis and degradation. Discovery of structure Coenzyme A was ident ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


4-coumaroyl-CoA
Coumaroyl-coenzyme A is the thioester of coenzyme-A and coumaric acid. Coumaroyl-coenzyme A is a central intermediate in the biosynthesis of myriad natural products found in plants. These products include Monolignol, lignols (precursors to lignin and lignocellulose), flavonoids, isoflavonoids, coumarins, aurones, stilbenes, catechin, and other phenylpropanoids. Biosynthesis and significance It is generated in nature from phenylalanine, which is converted by Phenylalanine ammonia-lyase, PAL to trans-cinnamate. Trans-cinnamate is hydroxylated by trans-cinnamate 4-monooxygenase to give 4-hydroxycinnamate (i.e, coumarate). Coumarate is condensed with coenzyme-A in the presence of 4-coumarate-CoA ligase: :ATP + 4-coumarate + CoA \rightleftharpoons AMP + diphosphate + 4-coumaroyl-CoA. Enzymes using Coumaroyl-Coenzyme A * Anthocyanin 3-O-glucoside 6''-O-hydroxycinnamoyltransferase * Anthocyanin 5-aromatic acyltransferase * Chalcone synthase * 4-Coumarate-CoA ligase * 6'-Deoxychalcon ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Malonyl-CoA
Malonyl-CoA is a coenzyme A derivative of malonic acid. Biosynthesis Malonyl-CoA cannot cross membranes and there is no known malonyl-CoA import mechanism. The biosynthesis therefore takes place locally: * cytosol: Malonyl-CoA is formed by carboxylating acetyl-CoA using the highly regulated enzyme acetyl-CoA carboxylase 1 (ACC1). One molecule of acetyl-CoA joins with a molecule of bicarbonate, requiring energy rendered from ATP. * Mitochondrial outer membrane: Malonyl-CoA is formed by carboxylating acetyl-CoA using the highly regulated enzyme acetyl-CoA carboxylase 2 (ACC2). The reaction is the same as with ACC1. * mitochondrial matrix: Malonyl-CoA is formed in coordinated fashion by mtACC1, a mitochondrial isoform of ACC1, and acyl-CoA synthetase family member 3 (ACSF3), a mitochondrial malonyl-CoA synthetase. MtACC1, like cytosolic ACC1 catalyses the carboxylation of acetyl-CoA, while ACSF3 catalyses the thioesterification of malonate to coenzyme A. The latter serves ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Chalcone Isomerase
In enzymology, a chalcone isomerase () is an enzyme that catalyzes the chemical reaction :a chalcone \rightleftharpoons a flavanone Hence, this enzyme has one substrate, a chalcone, and one product, a flavanone. This enzyme belongs to the family of isomerases, specifically the class of intramolecular lyases. The systematic name of this enzyme class is flavanone lyase (decyclizing). This enzyme is also called chalcone-flavanone isomerase. This enzyme participates in flavonoid biosynthesis. The ''Petunia hybrida'' (Petunia) genome contains two genes coding for very similar enzymes, ChiA and ChiB, but only the first seems to encode a functional chalcone isomerase. Structural studies As of late 2007, 7 structures have been solved for this class of enzymes, with PDB accession codes , , , , , , and . Chalcone isomerase has a core 2-layer alpha/beta structure A structure is an arrangement and organization of interrelated elements in a material object or system, or the objec ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]