108-26-9Relevant articles and documents
Stereoselective synthesis of trans-3-functionalized-4-pyrazolo[5,1-b]thiazole-3-carboxylate substituted β-lactams: Potential synthons for diverse biologically active agents
Berry, Shiwani,Bari, Shamsher S.,Yadav, Pooja,Garg, Ankita,Khullar, Sadhika,Mandal, Sanjay K.,Bhalla, Aman
, p. 1 - 12 (2020)
An efficient protocol for the stereoselective synthesis of pyrazolo[5,1-b]thiazole-3-carboxylate tethered β-lactam conjugates 8a–j from novel pyrazolo [5,1-b]thiazole-3-carboxylate substituted Schiff’s bases 6a–f is reported here. The reaction between various ketene precursors and novel Schiff’s bases 6a–f afforded exclusive formation of trans-β-lactams 8a–j. The substrate scope of this approach was investigated extensively by varying different groups (R, Z). All the novel compounds were characterized using various spectroscopic techniques, such as FT-IR, 1H NMR, 13C NMR, elemental analysis, 13C NMR (DEPT-135), and mass spectrometry in representative cases. Single crystal X-ray crystallographic study of trans-ethyl 7-(1-(4-methoxyphenyl)-4-oxo-3-phenoxyazetidin-2-yl)-6-methyl-2-(methylthio)pyrazolo[5,1-b]thiazole-3-carboxylate 8a has confirmed the molecular structure and the stereochemical outcome. To the best of our knowledge, the synthesis of such types of Schiff’s bases and β-lactam conjugates has not been reported so far.
Synthesis and Evaluation of Pyrazole Derivatives as Potent Antinemic Agents
Dhillon, N. K.,Jain, N.,Kaur, G.,Utreja, D.
, p. 113 - 118 (2020)
Pyrazole derivatives were synthesized by bromination of pyrazole, followed by N-alkylation of 4-bromopyrazole. The synthesized derivatives were characterized by microanalytical data and IR and 1H and 13C NMR spectra and were evaluated for their nematicidal activity against the root knot nematode Meloidogyne incognita. The compounds were screened for their egg hatch inhibition and mortality potential, and they showed significant nematicidal activity as compared to the control. 1H-Pyrazol-5(4H)-one was found to be most effective in egg hatch inhibition, and 4-bromopyrazole was found to be most effective in juvenile mortality.
SBA-Pr-SO3H-catalyzed synthesis of bispyrazole compounds as anti-bacterial agents and inhibitors of phosphorylated RET tyrosine kinase
Mohammadi Ziarani, Ghodsi,Saidian, Fatemeh,Gholamzadeh, Parisa,Badiei, Alireza,Ghasemi, Jahan B.,Aghaee, Elham,Abolhasani Soorki, Ali
, p. 1401 - 1409 (2019)
Pyrazolone was prepared through the reaction of ethyl acetoacetate and hydrazine hydrate in EtOH at room temperature. Then, bispyrazole derivatives, as attractive biologically active compounds, were synthesized by reacting two equivalents of prepared pyrazolone and one equivalent of aldehyde in the presence of SBA-Pr-SO3H under solvent-free condition at 120?°C. The reaction time was short (3–6?min), while the products’ yield was high (85–97%). Discovery Studio 2.5 (Accelrys Inc, San Diego, CA, USA) was employed to dock the compounds to protein. Molecular docking (GOLD method) studies suggested that pyrazoles bind efficiently to RET kinase. Next, biological activities of the bispyrazoles were tested against some Gram-positive and Gram-negative bacteria and for antifungal activity via the disc-diffusion method. All compounds showed no significant anti-bacterial activities, but two of them showed good activities against Candida albicans. Graphical abstract: [Figure not available: see fulltext.]
A new, convenient and expeditious synthesis of 4-alkyl-5-methyl-1H-pyrazol-3-ols in water through a multicomponent reaction
Kalita, Subarna Jyoti,Bayan, Rajarshi,Devi, Jutika,Brahma, Sanfaori,Mecadon, Hormi,Deka, Dibakar Chandra
, p. 566 - 569 (2017)
A new, simple and efficient synthesis of 4-alkyl-5-methyl-1H-pyrazol-3-ols in water by a two-pot four component reaction of ethyl acetoacetate, hydrazine hydrate, aldehyde and ketone in presence K2CO3as the catalyst is described. Use of water as the reaction medium, operational simplicity, mild reaction conditions, application of a cost-effective, nontoxic and easily available catalyst with auto-tandem catalysis, wide substrate scope, easy workup and purification process make the protocol highly attractive.
Heterocyclic derivatives of sugars: The formation of 1-glycosyl-3-methylpyrazol-5-ones from hydrazones
Kett, Warren C,Batley, Michael,Redmond, John W
, p. 169 - 177 (2000)
Conditions to effect the conversion of monosaccharide and disaccharide hydrazones to 1-glycosyl-3-methylpyrazol-5-ones were examined. The sugar pyrazolone derivatives were sensitive to oxidation, but high yields were achieved with 2,2,2-trifluoroethyl acetoacetate in mildly acidic solution. Azo coupling of the pyrazolones produced highly coloured azopyrazolone derivatives that prevented further degradation, and these may prove useful labels for chromatographic analysis of carbohydrates. (C) 2000 Elsevier Science Ltd.
Bougault,Cattelain,Chabrier
, (1948)
Expeditious synthesis of functionalized tricyclic 4-spiro pyrano[2,3-c]pyrazoles in aqueous medium using dodecylbenzenesulphonic acid as a Br?nsted acid-surfactant-combined catalyst
Mukherjee, Prasun,Paul, Sanjay,Das, Asish R.
, p. 9480 - 9486 (2015)
An efficient, three-component, one-pot synthesis of highly functionalized tricyclic 4-spiro pyrano[2,3-c]pyrazoles incorporating medicinally privileged heterocyclic moieties has been developed, which also involves the tandem Knoevenagel/Michael addition reaction followed by dehydrative cyclization of pyrazolone derivatives, cyclic 1,3-diketones and cyclic ketones, catalyzed by dodecylbenzenesulphonic acid (DBSA) as a Br?nsted acid-surfactant-combined catalyst in aqueous medium. The catalyst is found to be highly competent in accelerating this reaction that results in a considerable short reaction time, alleviating the need for high thermal energy. Wide substrate scope, high to excellent product yield, operational simplicity, absence of any hazardous organic solvent, mild reaction conditions, a simple work up procedure and easily available starting materials are the salient features of this protocol.
Microwave domino diastereoselective synthesis of novel trans-4,5-dihydro-1H-furo[2,3-c]pyrazoles using pyridinium salts in an aqueous medium
Yazdani-Elah-Abadi, Afshin,Morekian, Reza,Simin, Nasim,Lashkari, Mojtaba
, p. 219 - 223 (2018)
Novel fused 4,5-dihydro-1H-furo[2,3-c]pyrazole derivatives containing both biologically active pyrazole and furan templates are synthesised by a one-pot two-step four-component domino reaction involving hydrazine hydrate, a β-keto ester, an aromatic aldehyde and a pyridinium salt catalysed by DABCO with high diastereoselectivity in H2O under microwave irradiation. To minimise the formation of byproducts, the hydrazine hydrate and ethyl acetoacetate were first irradiated until a pyrazolone was formed. Next, the aryl aldehyde, the pyridinium salt and DABCO were added and the reaction could be completed in good to excellent yields. The salient features of this eco-friendly methodology are highlighted by its short reaction time (10–12 min), high yields, high atom-economy, efficiency of producing five new bonds (2C–C, C=N, C–N and one C–O), two new rings and two stereocentres in a single operation, absence of any tedious work-up or purification and avoidance of separation of intermediates.
A novel method for the synthesis of pyrazolo[5,1-b]thiazole
Wang, Zhongwen,Ren, Jun,Li, Zhengming
, p. 763 - 769 (2000)
By a new tandem reaction, in which ethyl 1-pyrazolacetate reacted with carbon disulfide and iodomethane, pyrazolo[5,1-b]thiazole was synthesized. This was an easy method for the synthesis of this type of heterocyles.
Synthesis and cytotoxic evaluation of some substituted pyrazole zirconium (IV) complexes and their biological assay
El-Shwiniy, Walaa H.,Shehab, Wesam S.,Mohamed, Soha F.,Ibrahium, Hend G.
, (2018)
Pyrazole and their derivatives are found to have intense biological efficiency. In the present work some substituted pyrazole derivatives were synthesized and used as ligands (4-[2-vinylthiophene]-3-methyl pyrozolin-5(4H) - one (L1), 4-[4-chloro benzylidine]-3-methyl pyrozolin-5(4H) - one (L2) and 4-[4-dimethylnitro benzylidine]-3-methylpyrozolin-5(4H) - one (L3)) to prepare the zirconium (IV) complexes. The synthesized ligands and their complexes were obtained as colored powdered materials and were characterized using magnetic measurements, melting point, molar conductance, infrared, electronic, 1HNMR, mass spectra and thermogravimetric analyses. All of the tested compounds showed good microbial activity against pathogenic microorganisms. The tested compounds exhibited considerable antitumor activity and cytotoxic specificity towards human colon carcinoma cell line (HCT-116).
Facile, one-pot, four-component synthesis of a new series of imidazo[1,2-a]pyridines in presence of TPAB in EtOH under reflux conditions
Etivand, Nasser,Khalafy, Jabbar,Poursattar Marjani, Ahmad
, (2019)
Abstract: A convenient, regioselective, novel, and elegant one-pot, four-component reaction was designed for synthesis of a series of new of imidazo[1,2-a]pyridines using aryl glyoxal monohydrates, ethyl acetoacetate, hydrazine hydrate, and 2-aminopyridine in presence of tetrapropylammonium bromide under reflux in EtOH as solvent. The main advantages of this protocol include the availability and low cost of the starting materials, short reaction time, convenient operation, easy workup process, highly facile operation, nonhazardous byproducts, and high yield (82–94%). Graphical abstract: [Figure not available: see fulltext.].
DABCO-catalyzed Five-component Domino Protocol for the Synthesis of Novel Benzo[a]pyrazolo[4’,3’:5,6]pyrano[2,3-c]phenazines in PEG-400 as an Efficient Green Reaction Medium
Lashkari, Mojtaba,Mohebat, Razieh,Yazdani-Elah-Abadi, Afshin
, (2020)
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Antitubercular 2-Pyrazolylpyrimidinones: Structure-Activity Relationship and Mode-of-Action Studies
Soares De Melo, Candice,Singh, Vinayak,Myrick, Alissa,Simelane, Sandile B.,Taylor, Dale,Brunschwig, Christel,Lawrence, Nina,Schnappinger, Dirk,Engelhart, Curtis A.,Kumar, Anuradha,Parish, Tanya,Su, Qin,Myers, Timothy G.,Boshoff, Helena I. M.,Barry, Clifton E.,Sirgel, Frederick A.,Van Helden, Paul D.,Buchanan, Kirsteen I.,Bayliss, Tracy,Green, Simon R.,Ray, Peter C.,Wyatt, Paul G.,Basarab, Gregory S.,Eyermann, Charles J.,Chibale, Kelly,Ghorpade, Sandeep R.
supporting information, p. 719 - 740 (2021/02/03)
Phenotypic screening of a Medicines for Malaria Venture compound library against Mycobacterium tuberculosis (Mtb) identified a cluster of pan-active 2-pyrazolylpyrimidinones. The biology triage of these actives using various tool strains of Mtb suggested a novel mechanism of action. The compounds were bactericidal against replicating Mtb and retained potency against clinical isolates of Mtb. Although selected MmpL3 mutant strains of Mtb showed resistance to these compounds, there was no shift in the minimum inhibitory concentration (MIC) against a mmpL3 hypomorph, suggesting mutations in MmpL3 as a possible resistance mechanism for the compounds but not necessarily as the target. RNA transcriptional profiling and the checkerboard board 2D-MIC assay in the presence of varying concentrations of ferrous salt indicated perturbation of the Fe-homeostasis by the compounds. Structure-activity relationship studies identified potent compounds with good physicochemical properties and in vitro microsomal metabolic stability with moderate selectivity over cytotoxicity against mammalian cell lines.
