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Tatiana S. Kokovina Svyatoslav Y. Gadomsky Alexei A. Terentiev Nataliya A. Sanina 《Molecules (Basel, Switzerland)》2021,26(17)
The main purpose of the study was the development of a new method for synthesis of 1,3,4-thiadiazol-2-amine derivatives in a one-pot manner using the reaction between a thiosemicarbazide and carboxylic acid without toxic additives such as POCl3 or SOCl2. The reaction was investigated in the presence of polyphosphate ester (PPE). It was found that, in the presence of PPE, the reaction between the thiosemicarbazide and carboxylic acid proceeds in one-pot through three steps with the formation of corresponding 2-amino-1,3,4-thiadiazole. Using the developed approach five, 2-amino-1,3,4-thiadiazoles were synthesized. The structures of all compounds were proven by mass spectrometry, IR, and NMR spectroscopies. 相似文献
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An efficient method for the one-pot synthesis of unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles has been developed using trichloroisocyanuric acid (TCCA) at ambient temperature. A wide variety of aromatic as well as heterocyclic aldehydes exhibit condensation with a variety of acylhydrazines followed by oxidative cyclization to yield corresponding unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles. The mild nature of the synthesis and short reaction time are notable advantages of the developed protocol. 相似文献
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A robust one-pot solution-phase synthesis of 2-amino-1,3,4-oxadiazoles directly from acylhydrazines and isothiocyanates is described. Commercially-available polymer-supported reagents help facilitate both cyclization and purification. This convenient method benefits from its broad applicability, ease and safety of reagent handling, simple product isolation, and the ability to perform multiple reactions in parallel fashion without need for purification. The details and scope of this reaction strategy are presented herein. 相似文献
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Bade Thirupaiah 《合成通讯》2014,44(4):513-519
A one-pot procedure has been developed for the synthesis of substituted 2,3-dihydro-2-(6-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7H-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazin-3-yl)phthalazine-1,4-diones by reaction of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and phthalic anhydrides in acetic acid medium. Similarly, a one-pot, three-component synthetic procedure has been developed for substituted 3-[3-(N1-benzylidene-hydrazino)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-4-hydroxy-6-methyl-pyran-2-ones from 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and various aromatic aldehydes in absolute ethanol and a few drops of glacial acetic acid.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
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An efficient and regioselective synthesis of 2-imino-1,3-selenazolidin-4-ones and 2-amino-1,3,4-selenadiazin-5-ones was achieved via one-pot reaction of isoselenocyanates, hydrazines, and ethyl chloroacetate or chloroacetyl chloride, respectively. Plausible mechanisms for these transformations were given. 相似文献
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Diammonium hydrogen phosphate and potassium carbonate-catalyzed one-pot synthesis of 1,4- phenylene-bis(2-amino-4H-pyran-3-carbonitrile and 2-amino-4-aryl-4H-pyran-3-carbonitrile deriva- tives has been achieved by a three-component cyclocondensation of aldehydes, malononitrile, and different nucleophiles in aqueous medium in high yields. 相似文献
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《Tetrahedron: Asymmetry》2007,18(16):1975-1980
l-Proline catalyzed direct diastereoselective aldol reactions of α-amino aldehydes with cyclic ketones have been described and utilized further for the stereoselective synthesis of the 2-amino-1,3,4-triol unit as the phytosphingosines base backbone. This leads to the formal synthesis of (2S,3S,4S)-lyxo-phytosphingosine. 相似文献
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Russian Journal of General Chemistry - A highly efficient one-pot three-component synthesis of 2-amino-3-cyano-4H-chromenes has been developed by annulation of aldehydes, malononitrile and dimedone... 相似文献
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An efficient one-pot synthetic method for the highly substituted 5H-[1,3,4]thiadiazolo[3,2-a]pyrimidine-6-carboxylate derivatives has been accomplished via a microwave irradiation of MCRs of various aldehydes, 2-aminothiadiazole, and acetoacetate without any catalyst in acetic acid. This approach provides a convenient one pot method for the synthesis of 5H-[1,3,4]thiadiazolo[3,2-a]pyrimidine-6-carboxylate derivatives. 相似文献
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An efficient and convenient approach is reported for three-component, one-pot synthesis of the [1,2,4]triazolo/benzimidazolo quinazolinones by condensation of 2-amino benzimidazole or 3-amino-1,2,4-triazole as amine sources with dimedone and different aldehydes in the presence of sulfamic acid as a reusable, green catalyst in acetonitrile and under heating conditions. 相似文献
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以2-氨基-5-烃基-1,3,4-噻二唑和水杨醛为原料,分别用"分步法"和"一锅法"经还原中间产物Schiff碱的CN双键合成了一系列2-((1,3,4-噻二唑基)胺甲基)苯酚类新化合物,"一锅法"的产率较高,为56%~80%。产物的结构用IR、1H NMR、13C NMR和MS进行了表征。初步测试了目标化合物的杀菌活性,证明化合物对赤星病菌具有较好的抑菌活性,当浓度为25 mg/L时,化合物3i的抑制率为76%,化合物3f、3h、3k和3l的为70%。 相似文献
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William A. Remers Gabriel J. Gibs Martin J. Weiss 《Journal of heterocyclic chemistry》1969,6(6):835-840
A new route for the synthesis of 2-amino-5-(l-methyl-5-nitro-2-imidazolyl)-1,3,4-thiadiazole ( 1 ) is described. This route was based upon the preparation of 2-amino-5-halomethyl-1,3,4-thiadiazoles by condensation of haloacetic acids with thiosemicarbazide. One of these intermediates, 2-acetamido-5-dichloromethyl-1,3,4-thiadiazole ( 4 ), was hydrolyzed to the corresponding 5-amino-2-carboxaldehyde 6 , which was trapped as its oxime 5 . 5-Acetamido-1,3,4-thiadiazole-2-carbonitrile ( 7 ), formed upon dehydration of 5 , was then converted into 2-amino-5-(2-imidazolyl)-1,3,4-thiadiazole ( 11 ) by a route based on the Pinner amidine synthesis. Methylation and nitration of the imidazole moiety then completed the preparation of 1. 相似文献
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A facile and efficient one-pot synthesis of 1,4-disubstituted 3-amino-2-pyridone derivatives via three-component reactions of readily available alkynyl aldehydes, amines, and ethyl 2-((diphenylmethylene)amino)acetate has been developed. The alkynyl aldehyde substrates and the amine partners can be flexibly varied to achieve a range of 3-amino-2-pyridone derivatives, which could exert interesting chemical and biological properties. The reaction mechanism for the formation of 3-amino-2-pyridone derivatives is briefly explained. 相似文献
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Yogesh B. Wagh Yogesh A. Tayade Swapnil A. Padvi Bhupesh S. Patil Nilesh B. Patil Dipak S. Dalal 《中国化学快报》2015,26(10):1273-1277
A rapid, one-pot and highly efficient protocol for the synthesis of pharmaceutically interesting functionalized 2-amino-3-cyano-4H-pyran and spirooxindole derivatives has been developed using commercially available Cs F as a catalyst in the reaction of malononitrile and aryl aldehydes or isatins with 1,3-cyclohexanediones. The major advantages of this methodology are excellent yield at ambient temperature, very short reaction time(5–10 min), and use of an inexpensive catalyst. 相似文献
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A highly efficient and environmentally benign protocol for the synthesis of 2-amino-5,7-dimethoxy-4-aryl/alkyl-4H-chromene-3-carbonitrile derivatives by one-pot three-component coupling reacting of aromatic aldehydes, malononitrile and 3,5-dimethoxy phenol under reflux condition has been developed in aqueous Et OH media using Na2O-Al2O3-P2O5glass–ceramic system. 相似文献
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Majid M. Heravi Tayebeh Hosseinnejad Zeinab Faghihi Morteza Shiri Mahdiyeh Vazinfard 《Journal of the Iranian Chemical Society》2017,14(4):823-832
An efficient, high yielding and environmentally benign strategy to the synthesis of new 2-amino-3-cyano-4-H-chromene derivatives, via one-pot three-component reaction involving malononitrile, various α- or β-naphthol and appropriate aromatic aldehydes including 2-chloroquinoline-3-carbaldehydes in the presence of morpholine in water, was achieved. During the development of the synthesis five new chromene derivatives were fruitfully synthesized. It was found that employing this approach, aromatic aldehydes bearing electron-withdrawing groups give higher yields of the corresponding products in shorter reaction times. This observation was in agreement with topological analysis of calculated electron density functions using density functional theory and quantum theory of atoms in molecules approaches. 相似文献
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M. A. Kukaniev M. M. Akbarova Z. G. Sangov S. S. Safarov D. M. Osimov 《Chemistry of Heterocyclic Compounds》2010,46(5):605-607
A one-reactor method has been developed for the synthesis of 3-methyl-6-R-6H-thiazolo[4,3-b]-1,2,4-triazolo[4,3-d]-1,3,4-thiadiazoles
by the condensation of aromatic aldehydes, thioglycolic acid, and 4-amino-5-methyl-1,2,4-triazole-3(2H)-thione in a sulfuric
acid medium. 相似文献
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A new methodology has been developed towards the room temperature synthesis of novel 2-amino-5-alkylidenethiazol-4-ones from aldehydes, amines and rhodanine in one-pot. A heterogeneous dipolar catalyst has been utilized for this reaction. The unique properties of this catalyst effectively synthesize such compounds at room temperature in contrast to all earlier reports. 相似文献