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Oxadiazole
Oxadiazoles are a class of heterocyclic aromatic chemical compounds of the azole family with the molecular formula . There are four isomers of oxadiazole: File:1,2,3-oxadiazole.svg, 1,2,3-oxadiazole File:1,2,4-oxadiazole.svg, 1,2,4-oxadiazole File:1,2,5-oxadiazole.svg, 1,2,5-oxadiazole(furazan) File:1,3,4-oxadiazole.svg, 1,3,4-oxadiazole 1,2,4-Oxadiazole, 1,2,5-oxadiazole, and 1,3,4-oxadiazole are all known and appear in a variety of pharmaceutical drugs including raltegravir, butalamine, fasiplon, oxolamine, and pleconaril. The 1,2,3-isomer is unstable and ring-opens to form the diazoketone tautomer; however, it does exist within the unusual sydnone motif. In 2018, a compound called bis(1,2,4-oxadiazole)bis(methylene) dinitrate which might have 1.5 times the power of TNT was developed at the United States Army Research Laboratory (ARL) working with the Los Alamos National Laboratory Los Alamos National Laboratory (often shortened as Los Alamos and LANL) is one of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,3,4-Oxadiazole
1,3,4-Oxadiazole is a nitrogen and oxygen containing heterocycle, and one of the four isomers of oxadiazole. Derivatives 1,3,4-Oxadiazole itself is not commonly used in organic chemistry, but many of its derivatives are important. For example, raltegravir is an HIV drug which contains an 1,3,4-oxadiazole ring. Other pharmaceutical drugs containing the 1,3,4-oxadiazole ring include fenadiazole, zibotentan, and tiodazosin. 1,3,4-Oxadiazole derivatives can be synthesized in a variety of ways. One pathway is from oxidation of tetrazoles in the presence of aldehydes. Similarly, the reaction of tetrazoles with acyl chloride In organic chemistry, an acyl chloride (or acid chloride) is an organic compound with the functional group . Their formula is usually written , where R is a side chain. They are reactive derivatives of carboxylic acids (). A specific example o ...s provides oxadiazoles. Both methods involve the release of N2. See also * Furazan (1,2,5-oxadiazole) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azole
Azoles are a class of five-membered heterocyclic compounds containing a nitrogen atom and at least one other non-carbon atom (i.e. nitrogen, sulfur, or oxygen) as part of the ring. Their names originate from the Hantzsch–Widman nomenclature. The parent compounds are aromatic and have two double bonds; there are successively redox, reduced analogs (azolines and azolidines) with fewer. One, and only one, lone pair of electrons from each heteroatom in the ring is part of the aromatic bonding in an azole. Names of azoles maintain the prefix upon reduction (e.g., pyrazoline, pyrazolidine). The numbering of ring atoms in azoles starts with the heteroatom that is not part of a double bond, and then proceeds towards the other heteroatom. Imidazole and other five-membered aromatic heterocyclic systems with two nitrogens are extremely common in nature and form the core of many biomolecules, such as histidine. Compound classes ;Nitrogen only Imidazol.svg, Imidazole Pyrazol.svg, Pyrazol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Furazan
Furazan, or 1,2,5-oxadiazole, is a heterocyclic aromatic organic compound consisting of a five-atom ring containing 1 oxygen and 2 nitrogen atoms. The furazan ring system is also found in the steroid furazabol. Furazan and its derivatives are obtained from the oxime derivatives of 1,2- diketones. Synthesis In theory the simplest means of producing furazan is the cyclic-dehydration of (the di-oxime of glyoxal), however the instability of furazan to high temperature or extremes of pH requires that this process be performed carefully. The formation of furazan from glyoxime is also exothermic and takes place with the copious evolution of noxious gases. The reaction may be achieved by heating glyoxime to 150 °C in the presence of succinic anhydride. Furazan will evaporate at that temperature, which continuously removes the product from the reaction mixture. Derivatives ;3,4-Dimethylfurazan 3,4-Dimethylfurazan ( b.p. 154–159 °C) is prepared by an analogous process by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sydnone
Sydnones are mesoionic heterocyclic chemical compounds possessing a C5-oxygenated 1,2,3-oxadiazole core, named after the city of Sydney, Australia. Like other mesoionic compounds they are dipolar, possessing both positive and negative charges which are delocalized across the ring. Discovery N-phenylsydnone was first prepared in 1935 by and by cyclodehydration of N-Nitroso- N-phenylglycine with acetic anhydride. Later work showed that this could be applied fairly generally to the nitrosamines of N-substituted amino acids. The parent compound sydnone is not synthetically accessible and may not exist. Chemical structure Sydnones have the following resonance structures. The exocyclic oxygen atom (O6) has a significant negative charge. Recent computational studies have indicated that sydnones and other similar mesoionic compounds are nonaromatic, "though well-stabilized in two separate regions by electron and charge delocalization." Examples * Cefanone ( Cephanone) * Ipra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocyclic
A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of organic heterocycles. Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. More than half of known compounds are heterocycles. 59% of US FDA-approved drugs contain nitrogen heterocycles. Classification The study of organic heterocyclic chemistry focuses especially on organic unsaturated derivatives, and the preponderance of work and applications involves unstrained organic 5- and 6-membered rings. Included are pyridine, thiophene, pyrrole, and furan. Another large class of organic heterocycles refers to those fused to benzene rings. For example, the fused benzene derivatives of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleconaril
Pleconaril (Picovir) is an antiviral drug that was being developed by Schering-Plough for prevention of asthma exacerbations and common cold symptoms in patients exposed to picornavirus respiratory infections. Pleconaril, administered either orally or intranasally, is active against viruses in the '' Picornaviridae'' family, including '' Enterovirus'' and ''Rhinovirus''. It has shown useful activity against the dangerous enterovirus D68. History Pleconaril was originally developed by Sanofi-Aventis, and licensed to ViroPharma in 1997. ViroPharma developed it further, and submitted a New Drug Application to the United States Food and Drug Administration (FDA) in 2001. The application was rejected, citing safety concerns; and ViroPharma re-licensed it to Schering-Plough in 2003. The Phase II clinical trial was completed in 2007. A pleconaril intranasal spray had reached phase II clinical trial for the treatment of the common cold symptoms and asthma complications. However, the res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bis-oxadiazole
Bis-oxadiazole, or more formally known as bis(1,2,4-oxadiazole)bis(methylene) dinitrate, is a nitrated heterocyclic compound of the oxadiazole family. Bis-oxadiazole is related to bis-isoxazole tetranitrate (BITN), which was developed at the United States Army Research Laboratory (ARL). With a high nitrogen content, these compounds are poised to release a large volume of very stable N2. It is a “melt-cast” explosive material that is potentially both more powerful and environmentally friendly alternative to TNT. Synthesis Glyoxal condenses with hydroxylamine to yield diaminoglyoxime (DAG). Treating DAG with in the presence of base at high temperature, followed by nitration, yields bis(1,2,4-oxadiazole). Replacement for TNT TNT is attractive explosive because it is a melt-castable. A low melting point of about 80 °C and high decomposition temperature Thermal decomposition, or thermolysis, is a chemical decomposition of a substance caused by heat. The decompos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxolamine
Oxolamine is a cough suppressant that is available as a generic drug in many jurisdictions. Oxolamine also has anti-inflammatory activity, which causes a reduction in irritation of the nerve receptors of the respiratory tract. It is mainly used for the treatment of pharyngitis, tracheitis, bronchitis, bronchiectasis and pertussis. Oxolamine is not approved in the USA, it may be marketed elsewhere internationally as a cough suppressant. It is listed as a prescription drug A prescription drug (also prescription medication, prescription medicine or prescription-only medication) is a pharmaceutical drug that is permitted to be dispensed only to those with a medical prescription. In contrast, over-the-counter drugs c ... in New Zealand legislation. Oxolamine is also approved in Taiwan for the treatment of respiratory tract inflammation. References Antitussives Oxadiazoles Diethylamino compounds {{respiratory-system-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fasiplon
Fasiplon (RU 33203) is a nonbenzodiazepine anxiolytic drug from the imidazopyrimidine family of drugs. Fasiplon binds strongly to benzodiazepine sites on the GABAA receptor and has similar anxiolytic effects in animals, but with less sedative or muscle relaxant action. It was developed by a team at Roussel Uclaf Roussel Uclaf S.A. was a French pharmaceutical company and one of several predecessor companies of today's Sanofi. It was the second largest French pharmaceutical company before it was acquired by Hoechst AG of Frankfurt, Germany in 1997, with p ... in the 1990sUS Patent 5869481 Anticonvulsive 1-ar(alk)ylimidazolin-2-ones and process for making References {{GABAAR PAMs Sedatives Imidazopyrimidines Oxadiazoles GABAA receptor positive allosteric modulators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butalamine
Butalamine is a vasodilator. Synthesis The reaction of benzamidoxime (1) with chlorine and subsequent reaction with cyanamide (3) gives 5-amino-3-phenyl-1,2,4-oxadiazole (4).Aron-Samuel Jan Marcel Didier, Sterne Jean Jacques, (1967 to). Base catalyzed alkylation Alkylation is a chemical reaction that entails transfer of an alkyl group. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting al ... with dibutylaminoethyl chloride (5) completes the synthesis of butalamine (6). : References Vasodilators Oxadiazoles {{cardiovascular-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raltegravir
Raltegravir, sold under the brand name Isentress, is an antiretroviral medication used, together with other medication, to treat HIV/AIDS. It may also be used, as part of post exposure prophylaxis, to prevent HIV infection following potential exposure. It is taken by mouth. Common side effects include trouble sleeping, feeling tired, nausea, high blood sugar, and headaches. Severe side effects may include allergic reactions including Stevens–Johnson syndrome, rhabdomyolysis, muscle breakdown, and liver problems. It is unclear if use during pregnancy or breastfeeding is safe. Raltegravir is an HIV integrase strand transfer inhibitor which blocks the functioning of HIV integrase which is needed for viral replication. Raltegravir was approved for medical use in the United States in 2007. It is on the WHO Model List of Essential Medicines, World Health Organization's List of Essential Medicines. Lamivudine/raltegravir, a combination medication, combination with lamivudine, is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatic
In organic chemistry, aromaticity is a chemical property describing the way in which a conjugated system, conjugated ring of unsaturated bonds, lone pairs, or empty orbitals exhibits a stabilization stronger than would be expected from conjugation alone. The earliest use of the term was in an article by August Wilhelm Hofmann in 1855. There is no general relationship between aromaticity as a chemical property and the olfaction, olfactory properties of such compounds. Aromaticity can also be considered a manifestation of cyclic delocalization and of Resonance (chemistry), resonance. This is usually considered to be because electrons are free to cycle around circular arrangements of atoms that are alternately single- and double-covalent bond, bonded to one another. This commonly seen model of aromatic rings, namely the idea that benzene was formed from a six-membered carbon ring with alternating single and double bonds (cyclohexatriene), was developed by Friedrich August Kekulé ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
