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Oxazines
Oxazines are heterocyclic compounds containing one oxygen and one nitrogen atom in a doubly unsaturated six-membered ring. Isomers exist depending on the relative position of the heteroatoms and relative position of the double bonds. By extension, the derivatives are also referred to as oxazines; examples include ifosfamide and morpholine (tetrahydro-1,4-oxazine). A commercially available dihydro-1,3-oxazine is a reagent in the Meyers synthesis of aldehydes. Fluorescent dyes such as Nile red and Nile blue are based on the aromatic benzophenoxazine. Cinnabarine and cinnabaric acid are two naturally occurring dioxazines, being derived from biodegradation of tryptophan. Dioxazines Dioxazines are pentacyclic compounds consisting of two oxazine subunits. A commercially important example is the pigment pigment violet 23. Benzoxazines Benzoxazines are bicyclic compounds formed by the ring fusion of a benzene ring with an oxazine. Polybenzoxazines are a class of polymers formed by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxazines
Oxazines are heterocyclic compounds containing one oxygen and one nitrogen atom in a doubly unsaturated six-membered ring. Isomers exist depending on the relative position of the heteroatoms and relative position of the double bonds. By extension, the derivatives are also referred to as oxazines; examples include ifosfamide and morpholine (tetrahydro-1,4-oxazine). A commercially available dihydro-1,3-oxazine is a reagent in the Meyers synthesis of aldehydes. Fluorescent dyes such as Nile red and Nile blue are based on the aromatic benzophenoxazine. Cinnabarine and cinnabaric acid are two naturally occurring dioxazines, being derived from biodegradation of tryptophan. Dioxazines Dioxazines are pentacyclic compounds consisting of two oxazine subunits. A commercially important example is the pigment pigment violet 23. Benzoxazines Benzoxazines are bicyclic compounds formed by the ring fusion of a benzene ring with an oxazine. Polybenzoxazines are a class of polymers formed by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenoxazine
Phenoxazine is a heterocyclic compound. The structure of phenoxazine consists of an oxazine fused to two benzene rings. It occurs as the central core of a number of naturally occurring chemical compounds such as dactinomycin and litmus. The dyes Nile blue and Nile red are also based on a phenoxazine core. Phenoxazine dyes were once widely used for silk dyeing, but due to their lack of lightfastness they have disappeared over time from the market. However, since their light resistance is significantly better on acrylic fibers, these dyes have experienced a renaissance. See also *Phenothiazine Phenothiazine, abbreviated PTZ, is an organic compound that has the formula S(C6H4)2NH and is related to the thiazine-class of heterocyclic compounds. Derivatives of phenothiazine are highly bioactive and have widespread use and rich history. T ... References {{heterocyclic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morpholine
Morpholine is an organic chemical compound having the chemical formula O( C H2CH2)2 NH. This heterocycle features both amine and ether functional groups. Because of the amine, morpholine is a base; its conjugate acid is called morpholinium. For example, treating morpholine with hydrochloric acid makes the salt morpholinium chloride. It is a colorless liquid with a weak, ammonia- or fish-like odor. The naming of morpholine is attributed to Ludwig Knorr, who incorrectly believed it to be part of the structure of morphine. Production Morpholine is often produced industrially by the dehydration of diethanolamine with sulfuric acid: : Uses Industrial applications Morpholine is a common additive, in parts per million concentrations, for pH adjustment in both fossil fuel and nuclear power plant steam systems. Morpholine is used because its volatility is about the same as water, so once it is added to the water, its concentration becomes distributed rather evenly in both the water a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzoxazine Resins
Benzoxazines are a group of isomeric bicyclic heterocyclic chemical compounds that consist of a benzene ring fused to an oxazine ring. The different isomers depend on the relative positions of the oxygen and nitrogen atoms in the oxazine ring, on the location of ring fusion, and on the position of the double bond in the oxazine ring. They have the molecular formula C8H7NO. Preparation 1,3-Benzoxazines can be synthesized by the Mannich reaction using a phenol, an amine, and formaldehyde. Uses Pharmaceutical drugs Benzoxazine rings form the central chemical structure of a number of pharmaceutical drugs including, for example, apararenone, elbasvir, and etifoxine. Polymers Polybenzoxazines, also called benzoxazine resins, are a class of polymers that are produced from the ring-opening polymerization of 3-phenyl-2,4-dihydro-1,3-benzoxazine monomers and its chemical derivatives The derivative of a function is the rate of change of the function's output relative to its input val ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoset Polymer Matrix
A thermoset polymer matrix is a synthetic polymer reinforcement where polymers act as binder or matrix to secure in place incorporated particulates, fibres or other reinforcements. They were first developed for structural applications, such as glass-reinforced plastic radar domes on aircraft and graphite-epoxy payload bay doors on the Space Shuttle. They were first used after World War II, and continuing research has led to an increased range of thermoset resins, polymers or plastics, as well as engineering grade thermoplastics. They were all developed for use in the manufacture of polymer composites with enhanced and longer-term service capabilities. Thermoset polymer matrix technologies also find use in a wide diversity of non-structural industrial applications. The foremost types of thermosetting polymers used in structural composites are benzoxazine resins, bis-maleimide resins (BMI), cyanate ester resins, epoxy (epoxide) resins, phenolic (PF) resins, unsaturated polyester ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polybenzoxazine
Polybenzoxazines, also called benzoxazine resins, are cured polymerization products derived from benzoxazine monomers. Monomers Benzoxazines are bicyclic heterocyclic compounds containing one oxygen and one nitrogen atom in a doubly unsaturated six-member ring, specifically a 1,3-oxazine ring, fused with a benzene ring. The systematic IUPAC name of the prototypical unsubstituted monomer is 3,4-dihydro-3-phenyl-2''H''-1,3-benzoxazine. Benzoxazines are products of condensation between an amine, a phenol and formaldehyde, used to produce thermoset resins or thermosetting polymer. Because of the wide availability and low-cost of starting materials (amines, phenols and formaldehyde), as well as ease of preparation (one-pot reaction) diverse benzoxazines are available. Numerous research focus on the different curing temperature, and polymer properties, such as cross-linking, from benzoxazines derived from substituted phenols. Commercial benzoxazines by Huntsman are based on bisphenols: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzoxazine
Benzoxazines are a group of isomeric bicyclic heterocyclic chemical compounds that consist of a benzene ring fused to an oxazine ring. The different isomers depend on the relative positions of the oxygen and nitrogen atoms in the oxazine ring, on the location of ring fusion, and on the position of the double bond in the oxazine ring. They have the molecular formula C8H7NO. Preparation 1,3-Benzoxazines can be synthesized by the Mannich reaction using a phenol, an amine, and formaldehyde. Uses Pharmaceutical drugs Benzoxazine rings form the central chemical structure of a number of pharmaceutical drugs including, for example, apararenone, elbasvir, and etifoxine. Polymers Polybenzoxazines, also called benzoxazine resins, are a class of polymers that are produced from the ring-opening polymerization of 3-phenyl-2,4-dihydro-1,3-benzoxazine monomers and its chemical derivatives The derivative of a function is the rate of change of the function's output relative to its input val ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pigment Violet 23
Pigment violet 23 is an organic compound that is a commercial pigment. It is member of the dioxazine family of heterocyclic compounds, but derived from carbazoles. It is prepared by condensation of chloranil and 3-amino-''N''-ethylcarbazole. It has a centrosymmetric angular structure. For many years, the structure was assigned, incorrectly, as having a "linear structure" (European Community number, EC no. 228-767-9, CAS RN 6358-30-1) which differ in terms of the carbazole ring fusion. Pigment violet 23 is prepared by condensation of an aniline with chloranil.Horst Tappe, Walter Helmling, Peter Mischke, Karl Rebsamen, Uwe Reiher, Werner Russ, Ludwig Schläfer and Petra Vermehren "Reactive Dyes"in Ullmann's Encyclopedia of Industrial Chemistry 2000, Wiley-VCH, Weinheim. {{doi, 10.1002/14356007.a22_651 References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tryptophan
Tryptophan (symbol Trp or W) is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α- carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromatic beta carbon substituent. It is essential in humans, meaning that the body cannot synthesize it and it must be obtained from the diet. Tryptophan is also a precursor to the neurotransmitter serotonin, the hormone melatonin, and vitamin B3. It is encoded by the codon UGG. Like other amino acids, tryptophan is a zwitterion at physiological pH where the amino group is protonated (–; pKa = 9.39) and the carboxylic acid is deprotonated ( –COO−; pKa = 2.38). Humans and many animals cannot synthesize tryptophan: they need to obtain it through their diet, making it an essential amino acid. Function Amino acids, including tryptophan, are used as building blocks in protein biosynthesis, and proteins are required to sustain life. Man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
