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.
Ligand based design and synthesis of pyrazole based derivatives as selective COX-2 inhibitors
Murahari, Manikanta,Mahajan, Vivek,Neeladri, Sreenivasulu,Kumar, Maushmi S.,Mayur
, p. 583 - 597 (2019)
The design and synthesis of novel pyrazole based derivatives has been carried out using the ligand based approach like pharmacophore and QSAR modelling of reported pyrazoles from the available literature to investigate the chemical features that are essential for the design of selective and potent COX-2 inhibitors. Both pharmacophore and QSAR models with good statistical parameters were selected for the design of the lead molecule. Also by exploiting the chemical structures of selective and marketed COX-2 inhibitors, celecoxib and SC-558 were used in designing the molecules which are used in the treatment of inflammation and related disorders. The therapeutic action of the Non-Steroidal Anti-inflammatory Agents (NSAIDs) is based primarily on the COX-2 inhibition. With this background we have synthesized some azomethine derivatives of 3-methyl-1-substituted-4-phenyl-6-[{(1E)-phenylmethylene}amino]-1,4-dihydro pyrano[2,3-c]pyrazole-5-carbonitrile 6(a-o) and were characterized by 1HNMR, 13CNMR and Mass spectral techniques. All the synthesized pyrazole derivatives were tested for in vitro membrane stability property in both COX-1 & COX-2 inhibition studies and in vivo anti-inflammatory activity by carrageenan induced rat paw edema model. Among them, compound 6k showed very good activity by in vivo anti-inflammatory activity with 0.8575 mmol/kg as ED50. Similarly compounds 6m, 6o, 6i and 6h exhibited comparable anti-inflammatory activity to standard drugs. Also the active compounds were further screened for ulcerogenic activity and were found be safer with less ulcer index compared to the marketed drugs like aspirin, ibuprofen and celecoxib.
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.
Fused Heterocyclic Compounds as Potent Indoleamine-2,3-dioxygenase 1 Inhibitors
Panda, Subhankar,Roy, Ashalata,Deka, Suman Jyoti,Trivedi, Vishal,Manna, Debasis
, p. 1167 - 1172 (2016)
Uncontrolled metabolism of l-tryptophan (l-Trp) in the immune system has been recognized as a critical cellular process in immune tolerance. Indoleamine 2,3-dioxygenase 1 (IDO1) enzyme plays an important role in the metabolism of a local l-Trp through the kynurenine pathway in the immune systems. In this regard, IDO1 has emerged as a therapeutic target for the treatment of diseases that are associated with immune suppression like chronic infections, cancer, and others. In this study, we synthesized a series of pyridopyrimidine, pyrazolopyranopyrimidine, and dipyrazolopyran derivatives. Further lead optimizations directed to the identification of potent compounds, 4j and 4l (IC50 = 260 and 151 nM, respectively). These compounds also exhibited IDO1 inhibitory activities in the low nanomolar range in MDA-MB-231 cells with very low cytotoxicity. Stronger selectivity for the IDO1 enzyme (>300-fold) over tryptophan 2,3-dioxygenase (TDO) enzyme was also observed for these compounds. Hence, these fused heterocyclic compounds are attractive candidates for the advanced study of IDO1-dependent cellular function and immunotherapeutic applications.
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.]
Synthesis of 6-amino-4-aryl-3-methyl-1,4-dihydropyrano[2,3-c]pyrazole-5- carbonitriles by heterogeneous reusable catalysts
Shaterian, Hamid Reza,Kangani, Mehrnoosh
, p. 1997 - 2005 (2014)
A new, efficient and environmentally benign protocol for the one-pot, four-component synthesis of 1,4-dihydropyrano[2,3-c]pyrazoles by reaction of hydrazine monohydrate, ethyl acetoacetate, arylaldehydes and malononitrile in the presence of a green catalytic amount of P2O5/SiO 2, H3PO4/Al2O3, cellulose sulfuric acid and starch sulfuric acid is described. The use of non-toxic and inexpensive materials, simple and clean work-up, short reaction times and good yields of the products are the advantages of this method.
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.
Polyethylene glycol-promoted synthesis of pyrimido[1,2-a]benzimidazole and pyrano[2,3-c]pyrazole derivatives in water
Survase, Dattatray,Bandgar, Babasaheb,Helavi, Vasant
, p. 680 - 687 (2017)
Synthesis of pyrimido[1,2-a]benzimidazole and pyrano[2,3-c]pyrazole derivatives were achieved using polyethylene glycol (PEG-400) as promoting reaction medium in water under catalyst-free conditions at reflux and room temperature, respectively. The structure of pyrimido[1,2-a]benzimidazole was confirmed using 1H NMR, 13C NMR, DEPT, and HMBC experiments. The promising points for the present methodology are efficiency, generality, high yield, short reaction time, cleaner reaction profile, ease of product isolation, simplicity, potential of recycling reaction medium, and finally agreement with green chemistry protocols.
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.
Synthesis of Pyranopyrazoles Using Magnetically Recyclable Heterogeneous Iron Oxide-silica Core-shell Nanocatalyst
Soleimani, Ebrahim,Jafarzadeh, Mohammad,Norouzi, Parastoo,Dayou, Jedol,Sipaut, Coswald Stephen,Mansa, Rachel Fran,Saei, Parisa
, p. 1155 - 1162 (2015)
The Fe3O4@SiO2 core-shell nanocatalyst were prepared and efficiently used for four-component coupling reaction of aromatic aldehydes, malononitrile, ethyl acetoacetate and hydrazine hydrate in water/ethanol mixture. Various aromatic aldehydes possessing electron-withdrawing and electron-donating groups in different positions on the ring were successfully transformed to substituted pyranopyrazoles in high yields in short time. The nanocatalyst was easily recovered, and reused five times without significant loss in cata- lytic activity and performance. The structure, size and morphology of the nanosized catalyst were studied by various techniques such as Fourier transform infrared spectroscopy, powder X-ray diffraction, dynamic light scattering and transmission electron microscopy.
