60-80-0Relevant articles and documents
Pd(ii)-Catalyzed alkyne annulation through allylic isomerization: synthesis of spiro-cyclopentadiene pyrazolones
Changmai, Sumi,Sultana, Sabera,Sarma, Bipul,Gogoi, Sanjib
supporting information, p. 6027 - 6030 (2021/06/21)
The Pd(ii)-catalyzed activation of Csp2-H bond and double alkyne annulation which proceedsviaallylic isomerization is reported for the first time. This reaction of antipyrines with alkynes provides an efficient synthetic route for the biologically important spiro-cyclopentadiene pyrazolones. In the presence of Lawesson's reagent, this Pd(ii)-catalyzed annulation reaction affords another spiro-cyclopentadiene pyrazolone which displays very good fluorescence properties.
Metal-Free Direct C–H Thiolation and Thiocyanation of Pyrazolones
Kittikool, Tanakorn,Yotphan, Sirilata
supporting information, (2020/02/13)
Metal-free approach for direct C–H thiolation and thiocyanation of N-substituted pyrazolones with disulfides and thiocyanate salts, respectively, are developed. These reactions allow the C–S bond coupling to proceed effectively under mild conditions, providing useful and convenient methods for preparation of a series of 4-thio-substituted pyrazolone analogues, which have potential applications in organic, medicinal and material chemistry. Preliminary mechanistic investigation suggested that radical processes are likely to involve in these transformations.
On/Off O2 Switchable Photocatalytic Oxidative and Protodecarboxylation of Carboxylic Acids
Bazyar, Zahra,Hosseini-Sarvari, Mona
, p. 13503 - 13515 (2019/10/11)
Photoredox catalysis in recent years has manifested a powerful branch of science in organic synthesis. Although merging photoredox and metal catalysts has been a widely used method, switchable heterogeneous photoredox catalysis has rarely been considered. Herein, we open a new window to use a switchable heterogeneous photoredox catalyst which could be turned on/off by changing a simple stimulus (O2) for two opponent reactions, namely, oxidative and protodecarboxylation. Using this strategy, we demonstrate that Au@ZnO core-shell nanoparticles could be used as a switchable photocatalyst which has good catalytic activity to absorb visible light due to the localized surface plasmon resonance effect of gold, can decarboxylate a wide range of aromatic and aliphatic carboxylic acids, have multiple reusability, and are a reasonable candidate for synthesizing both aldehydes/ketones and alkane/arenes in a large-scale set up. Some biologically active molecules are also shown via examples of the direct oxidative and protodecarboxylation which widely provided pharmaceutical agents.
Copper-catalyzed acylation of pyrazolones with aldehydes to afford 4-acylpyrazolones
Xiao, Yan,Wu, Xiaopeng,Teng, Jiangang,Sun, Song,Yu, Jin-Tao,Cheng, Jiang
supporting information, p. 7552 - 7557 (2019/08/20)
Copper-catalyzed direct acylation of the alkenyl C-H bond in 1,2-dihydro-3H-pyrazol-3-ones has been developed, affording a series of 4-acylpyrazolones in moderate to good yields. Notably, this protocol involves readily accessible substrates and reagents, which have good functional group tolerance leading to pyrazolone derivatives under mild reaction conditions.
DABCO-catalyzed silver-promoted direct thiolation of pyrazolones with diaryl disulfides
Thupyai, Akkharaphong,Pimpasri, Chaleena,Yotphan, Sirilata
supporting information, p. 424 - 432 (2018/02/06)
A highly efficient protocol for a direct thiolation of N-substituted pyrazolones with diaryl disulfides is described. Using a combination of DABCO and silver(i) acetate, the C-S bond formation proceeds smoothly at room temperature under mild and easy to handle conditions. This synthetic strategy offers a convenient and direct modification of antipyrine and other pyrazolone substrates, giving a series of aryl sulfide-substituted pyrazolone products in moderate to excellent yields.
Copper/Persulfate-Promoted Oxidative Decarboxylative C?H Acylation of Pyrazolones with α-Oxocarboxylic Acids: Direct Access to 4-Acylpyrazolones under Mild Conditions
Kittikool, Tanakorn,Thupyai, Akkharaphong,Phomphrai, Khamphee,Yotphan, Sirilata
, p. 3345 - 3355 (2018/09/10)
A facile and efficient oxidative C?H acylation of N-substituted pyrazolones using α-oxocarboxylic acids as an acyl group source was developed. A combination of Cu(OAc)2 and K2S2O8 enables the reaction to proceed smoothly under air and provides a wide array of 4-acylpyrazolone products in moderate to excellent yields. The mechanism of this transformation is believed to proceed via a copper-induced decarboxylation to form the acyl-copper species. This method provides a convenient and useful route for a direct installation of an acyl moiety into bioactive pyrazolone derivatives, which can be further utilized in many applications. (Figure presented.).
Design, synthesis, anti-inflammatory activity and molecular docking of potential novel antipyrine and pyrazolone analogs as cyclooxygenase enzyme (COX) inhibitors
El Sayed, Mardia T.,El-Sharief, Marwa A.M.Sh.,Zarie, Eman S.,Morsy, Nesrin M.,Elsheakh, Ahmed R.,Voronkov, Andrey,Berishvili, Vladimir,Hassan, Ghada S.
, p. 952 - 957 (2018/03/06)
As a part of a directed program for development of new active agents, novel heterocyclic derivatives with antipyrine and pyrazolone moieties -incorporated in- have been designed and synthesized. Starting with 4-arylidene-3-methyl-1-phenyl-5-pyrazolone derivative 2a,b novel Mannich bases derivatives have been synthesized and biologically evaluated for their anti-inflammatory activity. Furthermore, the activity of such compounds has been tested interestingly as COX-1 and COX-2 inhibitors. Structure elucidation of the synthesized compounds was attained by the use of elemental analysis, IR, 1H NMR, 13C NMR, and Mass spectrometry techniques. Compounds 3b, 3d and 4b represent the high % inhibition values for both COX-1 and COX-2. On the other hand, compound 8 showed little selectivity against COX-2 while compound 10 showed good selectivity against COX-1 only. Structure activity relationship has been discussed and the results were confirmed by molecular docking calculations.
Pyrazolone methylamino piperidine derivatives as novel CCR3 antagonists
Pegurier, Cecile,Collart, Philippe,Danhaive, Pierre,Defays, Sabine,Gillard, Michel,Gilson, Frederic,Kogej, Thierry,Pasau, Patrick,Van Houtvin, Nathalie,Van Thuyne, Marc,van Keulen, BerendJan
, p. 4228 - 4231 (2008/02/09)
The discovery and optimization of a novel class of potent CCR3 antagonists is described. Details of synthesis and SAR are given together with some ADME properties of selected compounds. An optimal balance between activities, physicochemical properties, and in vitro metabolic stability was reached by the proper choice of substituents.
PYRAZOLONE COMPOUNDS AS METABOTROPIC GLUTAMATE RECEPTOR AGONISTS FOR THE TREATMENT OF NEUROLOGICAL AND PSYCHIATRIC DISORDERS
-
Page/Page column 50, (2008/06/13)
Compounds of Formula (I), wherein R1, R2, R3, R4, R5, R6, X, and n are as defined for Formula (I) in the description, processes for the preparation of the compounds and new intermediates employed in the preparation, pharmaceutical compositions containing the compounds, and the use of the compounds in the treatment or prevention of neurological and psychiatric disorders associated with glutamate dysfunction.
Alkylation of pyrazolones via the mitsunobu reaction
Holzer, Wolfgang,Plagens, Brigitte,Lorenz, Karin
, p. 309 - 314 (2007/10/03)
The reaction of 3-methyl-1-phenyl-2-pyrazolin-5-one and 4-acyl derivatives thereof (R4 = COPh, 2-thienoyl, COCH2CH2Ph, COCH=CHPh) with various alcohols under 'Mitsunobu'-conditions was studied. In many cases selective O-alkylation could be achieved.
