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Almqvist, Pilicides–small molecules targeting bacterial virulence, Org. Different combinations of fragments were used: Dyachenko, Synthesis and properties of 3-cyanopyridine-2 1H -chalcogenones.
Another example of microwave synthesis of condensing type of 2-pyridones is shown in Figure 9 .
Abdou, Microwave-assisted synthesis of 2 1H -pyridones and their glucosides as cell proliferation inhibitors, Nucleos. This method cannot be applied in cases where an electron-acceptor group e. Nasuprot tome, mikrotalasno zracenje je efikasan izvor zagrevanja koji direktno prenosi energiju heteorciklicna interakciju sa polarnim molekulima prisutnim u reakcionoj smesi.
This type of synthesis involves the reaction of phenylazo carbonyl compounds and cyanoacetamide using KOH as base and ethanol as solvent in a dedicated neterociklicna reactor.
On the other hand, microwave irradiation is an efficient way of heating where energy is transmitted directly through interaction with polar molecules present in the reaction mixture [40,41].
Kappe, Rapid microwave-assisted solution phase synthesis of substituted 2-pyridone libraries, Tetrahedron 60 Condensation of type means that the condensation involves two acyclic systems one of which has four and the other only one carbon atom.
MijinJelena M. Separate each e-mail address with a semicolon Subject line: In the second part, microwave assisted synthesis of 2-quionolones is listed. In the second part, microwave assisted synthesis of 2-quionolones will be given.
Heterociklično jedinjenje — Википедија, слободна енциклопедија
In the first part, microwave synthesis of 2-pyridones according to the type of condensation is discussed. Aromatic heterocyclic compounds represent an important group of compounds due to their biological and medical applications. Recently, a synthesis heetrociklicna this pyridone was published, using microwave irradiation in a conventional microwave oven, in the absence of solvent starting from ethyl cyanoacetate and cyanoacetamide, using powdered potassium hydroxide as a catalyst Figure 5.
Condensed 2-pyridone derivatives can also be obtained from aminopropenoate obtained from dimethylformamide diethyl acetal DMFDEA and CH-acidic carbonyl compounds.
N-Methylpyridone is used in the production of compounds that are used to produce images heteociklicna. Kappe, Microwave-enhanced reactions under open and closed vessel conditions.
Microwaves have a frequency between 0. Thus conducted synthetic route yield pyridone ring from fragments containing different numbers of carbon atoms. US US Also, this type of reaction is used to obtain arylazo pyridone dyes .
Kappe, Controlled microwave heating in modern organic synthesis, Angew. Valentic, Synthesis and investigation of solvent effects on the ultraviolet jfdinjenja spectra of 5-substitutedmethylcyanohydroxypyridones, J. Syntheses were performed at [degrees]C both in the conventional and the microwave method. However, the use of microwave irradiation has a number of advantages over both conventional methods: The presence of [R. Reactions were performed in 1,2-dichloroethane DCE at [degrees]C for s .
tiofen – Heterociklična jedinjenja
The main advantages of microwave-assisted organic chemistry are the increase of product yields and the reduction of reaction time [43,44]. It should be noted that 4-quinolones can be obtained from substituted aniline and diethyl etoxymethylene malonate in a conventional microwave oven. Zbog siroke primene jedinjenja koja u sebi sadrze piridonsku strukturu razvijen je veliki broj postupaka za njihovu sintezu. Almqvist, Improved procedure for the enantioselective synthesis of dihydrooxazolo and dihydrothiazolo ring-fused 2-pyridones, Tetrahedron Letters 51 Besides the conventional synthesis, microwave assisted syntheses were also developed.
Twieg, Aromatic nucleophilic substitution with 4-hydroxypyridine, Tetrahedron Hetwrociklicna. It should be pointed out that a significant number of papers on the reactions of functionalization of 2-pyridone ring exist.
Visser, Rapid microwave-enhanced synthesis of 4-hydroxyquinolinones under solvent-free conditions, Tetrahedron Lett. Microwave synthesis of arylazo pyridone dyes  is based on the previously described type of condensation.
Synthesis of 2-pyridone based bifunctional compounds 1,4-dihydropyridines by the condensation of dialdehyde, Meldrum’s acid, acetoacetic acid and ammonium acetate is another example of type condensation of pyridones Figure 11 . This synthesis is given in Figure 2. Calmon, Effect of substituents on the keto-enol equilibriums of aromatic pdiketones in aqueous solution, C. Synthesis of 5-phenylazo-4,6-dimethylcyanopyridones and 5-phenylazo-4,6-diphenylcyanopyridone are shown in Figure 7.
Agarwal, Microwave prompted multigram synthesis, structural determination, and photo-antiproliferative activity of fluorinated 4-hydroxyquinolinones, Bioorg.
Nitrogen can be a part of one of the fragments, or be introduced as a separate fragment. The optically active bicyclopyridone was obtained by the reaction of acyl-ketenes with substituted [[DELTA].