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Münchnone
Münchnone (synonyms: 1,3-oxazolium-5-oxide; 1,3-oxazolium-5-olate; anhydro-5-hydroxy-1,3-oxazolium hydroxide; 5-hydroxy-1,3-oxazolium hydroxide, inner salt; oxido-oxazolium) is a mesoionic heterocyclic compound, heterocyclic aromatic chemical compound, with the molecular formula C3H3NO2. The name refers to the city of Munich, Germany (), where the compound and its derivatives were first discovered and studied. Synthesis and reactivity The first preparation of a münchnone derivative was reported in 1959 by Lawson & Miles by cyclodehydration of 2-pyridone-''N''-acetic acid with acetic anhydride. The azomethine ylide reactivity of münchnones, and their reaction with alkynes in the synthesis of pyrroles, was first published by Rolf Huisgen, Huisgen et al. The Huisgen group followed up with a thorough investigation of the chemical properties, reactivity, and utility of münchnones towards the synthesis of many other products. As such, they are typically credited for the discovery o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Montréalone
Montréalone (synonyms: montrealone, phospha-münchnone) is a mesoionic heterocyclic compound, heterocyclic chemical compound. It is named for the city of Montreal, Montréal, Canada, which is the location of McGill University, where it was first discovered. Structure The montréalone parent structure, parent compound has been studied theoretically, and is unlikely to exist as a stable species. structural analog, Analogs bearing multiple substituents display chemical stability, stability suitable for synthesis, isolation, and characterization. Substituted montréalones with a balance of chemical stability, stability and Reactivity (chemistry), reactivity have been used as reaction intermediates in the synthesis of other heterocyclic compound, heterocycles. Theoretical and experimental analysis of chemical stability, stable montréalones reveals overlapping azomethine ylide and Wittig reaction#Wittig reagents, Wittig-type moieties within the Saturated and unsaturated compounds, u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Sydnone Imine
{{Short description, Class of chemical compounds Sydnone imine is a mesoionic heterocyclic aromatic chemical compound. Sydnone imine is the imine of sydnone where the keto functional group of sydnone (=O) has been replaced with an imine (=NH) group. Pharmaceutical drugs A variety of pharmaceutical drugs include sydnone imines in their chemical structure including feprosidnine, linsidomine, mesocarb, and molsidomine, among others. Chemical structure In sydnone imines, both the negative and the positive charges are delocalized within the ring and the imine group. : See also * Montréalone * Münchnone * 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 wh ... External links IUPAC Goldbook entryDictionary of Organic Compounds Simple aromatic rings Oxadiazoles Imines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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] [Amazon] |
Oxazolone
Oxazolone is a chemical compound and functional group, with the molecular formula C3H3NO2. It was named in-line with the Hantzsch–Widman nomenclature and is part of a large family of oxazole based compounds. There are a total of 5 structural isomers of oxazolone; 3 according to the location of the carbonyl group and 2 more according to the location of the double bond C=X (with X= N or C): *2-(3''H'')oxazolone *2-(5''H'')oxazolone *4-(5''H'')-oxazolone *5-(2''H'')-oxazolone *5-(4''H'')-oxazolone The 4-oxazolone motif, which is also formally a lactam, is present in a number of drugs (fenozolone, thozalinone, cyclazodone, reclazepam etc.). Substituted 5-oxazolones may also be regarded as the cyclization products of ''N''-acyl α-amino acids, making them lactones, and are sometimes referred to as azlactones. See also * Münchnone * Oxazole * Oxazolidone — the saturated analogues References {{reflist Oxazolones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Mesoionic
In chemistry, mesoionic compounds are one in which a heterocyclic structure is dipolar and where both the negative and the positive charges are delocalized. A completely uncharged structure cannot be written and mesoionic compounds cannot be represented satisfactorily by any one mesomeric structure. Mesoionic compounds are a subclass of betaines. Examples are sydnones and sydnone imines (e.g. the stimulant mesocarb), münchnones, and mesoionic carbenes. The formal positive charge is associated with the ring atoms and the formal negative charge is associated either with ring atoms or an exocyclic nitrogen or other atom. These compounds are stable zwitterionic compounds and belong to nonbenzenoid 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 conjugati ...s. See also * Mesom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
In Situ
is a Latin phrase meaning 'in place' or 'on site', derived from ' ('in') and ' ( ablative of ''situs'', ). The term typically refers to the examination or occurrence of a process within its original context, without relocation. The term is used across many disciplines to denote methods, observations, or interventions carried out in their natural or intended environment. By contrast, ' methods involve the removal or displacement of materials, specimens, or processes for study, preservation, or modification in a controlled setting, often at the cost of contextual integrity. The earliest known use of ''in situ'' in the English language dates back to the mid-17th century. In scientific literature, its usage increased from the late 19th century onward, initially in medicine and engineering. The natural sciences typically use methods to study phenomena in their original context. In geology, field analysis of soil composition and rock formations provides direct insights into Earth' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
List Of Chemical Compounds With Unusual Names
Chemical nomenclature, replete as it is with compounds with very complex names, is a repository for some names that may be considered unusual. A browse through the ''Physical Constants of Organic Compounds'' in the ''CRC Handbook of Chemistry and Physics'' (a fundamental resource) will reveal not just the whimsical work of chemists, but the sometimes peculiar compound names that occur as the consequence of simple juxtaposition. Some names derive legitimately from their chemical makeup, from the geographic region where they may be found, the plant or animal species from which they are isolated or the name of the discoverer. Some are given intentionally unusual trivial names based on their structure, a notable property or at the whim of those who first isolate them. However, many trivial names predate formal naming conventions. Trivial names can also be ambiguous or carry different meanings in different industries, geographic regions and languages. Godly noted that "Trivial names h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Heterocyclic Compound
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 py ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Rolf Huisgen
Rolf Huisgen (; 13 June 1920 – 26 March 2020) was a German chemist. His importance in synthetic organic chemistry extends to the enormous influence he had in post-war chemistry departments in Germany and Austria, due to a large number of his habilitants becoming professors. His major achievement was the development of the 1,3-dipolar cycloaddition reaction, also called the Huisgen cycloaddition. Life Huisgen was born in Gerolstein in Rhineland-Palatinate and studied in Munich under the supervision of Heinrich Otto Wieland. He completed his Ph.D. in 1943 with a thesis about a strychnine alkaloid. He completed his habilitation in 1947, and was appointed professor at the University of Tübingen in 1949. He returned to the University of Munich in 1952, succeeding Wieland, and he remained dedicated to research long after attaining emeritus status there in 1988. One of his major achievements was the development of the 1,3-dipolar cycloaddition reaction, also known as the Hu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
