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1.
The rapidly growing human population has led to duplicate food production and also reduced product loss. Although the negative effects of synthetic chemicals were recorded, they are still used as agrochemical. The production of non-toxic synthetics makes their use particularly safe. The goal of our research is to evaluate antimicrobial activity of previously synthesized Poly(p-phenylene-1-(2,5-dimethylphenyl)-5-phenyl-1H-pyrazole-3,4-dicarboxy amide) (poly(PDPPD)) against selected Gram-negative, Gram-positive bacteria, and fungus. In addition, the possible genotoxic effects of the poly(PDPPD) were searched on Triticum vulgare and Amaranthus retroflexus seedlings using Random Amplified Polymorphic DNA (RAPD) marker. The binding affinity and binding energies of the synthesized chemical to B-DNA were simulated with AutoDock Vina. It was observed that the poly(PDPPD) affected most of the organisms in a dose-dependent manner. Pseudomonas aeruginosa was the most affected species in tested bacteria at 500 ppm with 21.5 mm diameters. Similarly, a prominent activity was observed for tested fungi. The poly(PDPPD) decreased root and stem length of the Triticum vulgare and Amaranthus retroflexus seedlings and also reduced the genomic template stability (GTS) value of Triticum vulgare more than Amaranthus retroflexus. The binding energy of poly(PDPPD) was found in range of −9.1 and −8.3 kcal/mol for nine residues of B-DNA.  相似文献   
2.
A series of new 4-(3-(4-substitutedphenyl)-3a,4-dihydro-3H-indeno[1,2-c]pyrazol-2-yl) benzenesulfonamides (712) was synthesized starting from 2-(4-substitutedbenzylidene)-2,3-dihydro-1H-inden-1-one (16) and 4-hydrazinobenzenesulfonamide. The substituted benzaldehydes from which the key intermediate was prepared by introducing 2- or 4-substituents such as fluorine, hydroxy, methoxy, or the 3,4,5-trimethoxy moieties. The compounds were tested for their cytotoxicity, tumor-specificity and potential as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. The 3,4,5-trimethoxy and the 4-hydroxy derivatives showed interesting cytotoxic activities, which may be crucial for further anti-tumor activity studies, whereas some of these sulfonamides strongly inhibited both human (h) cytosolic isoforms hCA I and II.  相似文献   
3.
Two new pyrazole-derived ligands, 1-ethyl-3,5-bis(2-pyridyl)pyrazole (L1) and 1-octyl-3,5-bis(2-pyridyl)pyrazole (L2), both containing alkyl groups at position 1 were prepared by reaction between 3,5-bis(2-pyridyl) pyrazole and the appropriate bromoalkane in toluene using sodium ethoxide as base.The reaction between L1, L2 and [MCl2(CH3CN)2] (M = Pd(II), Pt(II)) resulted in the formation complexes of formula [MCl2(L)] (M = Pd(II), L = L1 (1); M = Pd(II), L = L2 (2); M = Pt(II), L = L1 (3); M = Pt(II), L = L2 (4)). These complexes were characterised by elemental analyses, conductivity measurements, infrared, 1H, 13C{1H} NMR and HMQC spectroscopies. The X-ray structure of the complex [PtCl2(L2)] (4) was determined. In this complex, Npyridine and Npyrazole donor atoms coordinate the ligand to the metal, which complete its coordination with two chloro ligands in a cis disposition.  相似文献   
4.
A series of model compounds containing 3‐amino‐1Hpyrazole‐5‐carboxylic acid residue with N‐terminal amide/urethane and C‐terminal amide/hydrazide/ester groups were investigated by using NMR, Fourier transform infrared, and single‐crystal X‐ray diffraction methods, additionally supported by theoretical calculations. The studies demonstrate that the most preferred is the extended conformation with torsion angles ? and ψ close to ±180°. The studied 1Hpyrazole with N‐terminal amide/urethane and C‐terminal amide/hydrazide groups solely adopts this energetically favored conformation confirming rigidity of that structural motif. However, when the C‐terminal ester group is present, the second conformation with torsion angles ? and ψ close to ±180° and 0°, respectively, is accessible. The conformational equilibrium is observed in NMR and Fourier transform infrared studies in solution in polar environment as well as in the crystal structures of other related compounds. The observed conformational preferences are clearly related to the presence of intramolecular interactions formed within the studied residue. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
5.
New [(Indolyl)pyrazolyl]-1,3,4-oxadiazole compounds and their derived thioglycosides as well as the corresponding sugar hydrazones were synthesized. The acyclo C-nucleoside analogs of the oxadiazoline base system were also prepared by reaction of acid hydrazides with aldehydo sugars followed by one pot process encompassing acetylation and cyclization of the synthesized hydrazones. The anticancer activity of the newly synthesized compounds was studied against colorectal carcinoma (HCT116), breast adenocarcinoma (MCF7) and prostate cancer (PC3) human tumor cell lines and a number of compounds showed moderate to high activities.  相似文献   
6.
Reaction of molybdate and phosphate precursors in the presence of 3d transition metal ions and pyrazole (pz) under hydrothermal condition resulted in the crystallization of four new phosphomolybdate cluster based solids: (pz)2[{Co(pz)4}5{P2Mo5O23}2]·6H2O (1), (pz){Ni(pz)4(H2O)2}[{Ni(pz)4}5{P2Mo5O23}2]·2H2O (2), {Cu(pz)4(H2O)2}[{Cu(pz)4}{Cu(pz)4(H2O)}{P2Mo5O23}]·2H2O (3) and (pz)[{Zn(pz)3}3{P2Mo5O23}]·2H2O (4). In all the solids, a metal complex {M(pz)n} covalently links{P2Mo5O23} clusters to form a chain. The dimensionality of the structures differs in the way the chains link or self assemble with counter ions and water molecules. To the best of our knowledge, 4 is the first example of a zinc complex incorporated with {P2Mo5O23} cluster. The paper discusses the self assembly occurring between in situ metal pyrazole complex and phosphomolybdate clusters through coordinate/covalent and noncovalent interactions during crystallization of a particular solid.  相似文献   
7.
Six novel compounds of platinum(II) with pyrazole derivatives PtPz1–PtPz6 were synthesised and characterised (PtPz1 - [Pt2N-hydroksymethyl-3,5-dimethylpyrazole4(berenil)2]Cl4; PtPz2 - [Pt23,5-dimethylpyrazole4(berenil)2]Cl4; PtPz3 - [Pt23,4-dimethylpyrazole4(berenil)2]Cl4; PtPz4 - [Pt2pyrazole4(berenil)2]Cl4; PtPz5- [Pt25-methylpyrazole4(berenil)2]Cl4; PtPz6 - [Pt2N-ethylpyrazole4(berenil)2]Cl4). The cytotoxic activity of these complexes against MCF-7 and MDA-MB-231 breast cancer cell lines was determined using the MTT assay. Evaluation of apoptosis induction was done with the Annexin V-fluorescein isothiocyanate/propidium iodide assay. In addition, using a flow cytometer, we determined the influence of test compounds on the cell cycle and caspase-3, -8, and -9 activity. The obtained results of caspase activity were confirmed by cell imaging. Moreover, using the flow cytometer, the effects of the test compounds on mitochondrial potential change were assessed. The test results showed that novel pyrazole-platinum(II) complexes exhibited stronger anti-proliferative activity against two breast cancer cell lines than reference cisplatin. Compounds PtPz1, PtPz2, and PtPz3 with methyl substituents at the pyrazole ring showed stronger activity than pyrazole or ethylpyrazole containing complexes. Studies have shown that inhibition of cell survival occurs by arresting the G1 cell cycle and inducing apoptosis. Our analysis associated with the response of MCF-7 and MDA-MB-231 cells to treatment with PtPz1–PtPz6 showed that it leads the cells through the external and intrinsic (mitochondrial) apoptotic pathway via indirect DNA damage.  相似文献   
8.
A new series of benzimidazole linked pyrazole derivatives were synthesized by cyclocondensation reaction through one-pot multicomponent reaction in absolute ethanol. All the synthesized compounds were tested for their in vitro anticancer activities on five human cancer cell lines including MCF-7, HaCaT, MDA-MB231, A549 and HepG2. EGFR receptor inhibitory activities were carried out for all the compounds. Majority of the compounds showed potent antiproliferative activity against the tested cancer cell lines. Compound 5a showed the most effective activity against the lungs cancer cell lines (IC50 = 2.2 µM) and EGFR binding (IC50 = 0.97 µM) affinity as compared to other members of the series. Compound 5a inhibited growth of A549 cancer cells by inducing a strong G2/M phase arrest. In addition, same compound inhibited growth of A549 cancer cells by inducing apoptosis. In molecular docking studies compound 5a was bound to the active pocket of the EGFR (PDB 1M17) with five key hydrogen bonds and two π-π interaction with binding energies ΔG = −34.581 Kcal/mol.  相似文献   
9.
Antimicrobial resistance which is increasing at an alarming rate is a severe public health issue worldwide. Hence, the development of novel antibiotics is an urgent need as microbes have developed resistance against available antibiotics. In search of novel antimicrobial agents, a convenient route for the preparation of substituted 3-(1-phenyl-3-(p-tolyl)-1H-pyrazol-4-yl)-1-(2-phenyl-5-(pyridin-3-yl)-1,3,4-oxadiazol-3(2H)-yl)prop-2-en-1-ones ( 6a – 6o ) has been adopted by using pyridine-3-carbohydrazide and various aromatic aldehydes. The newly synthesized compounds were characterized by using various spectral techniques, for example, IR, 1H NMR, 13C NMR, and mass spectroscopy. Synthesized hybrids were studied for in vitro antimicrobial potency against various bacterial and fungal strains. Antibacterial results revealed that compounds 6e, 6h, 6i, 6l , and 6m were found to be most active against bacterial strains as they showed minimum inhibitory concentration (MIC) value of 62.5 μg/mL while compounds 6d, 6e , and 6h showed MIC value of 200 μg/mL against Candida albicans. The quantum parameters that relate to the bioavailability of the compounds were computed, followed by docking with different bacterial and fungal targets like sortase A, dihydrofolate reductase, thymidylate kinase, gyrase B, sterol 14-alpha demethylase. The experimental and computational results are in good agreement.  相似文献   
10.
This study aims to synthesize some novel pyrazolo[1,5-a]pyrimidine derivatives, and investigate their biological activities. These compounds exhibited good to high antioxidant activities [2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capabilities]. Among them, Ethyl 5-(2-ethoxy-2-oxoethyl)-7-hydroxy-2-methylpyrazolo[1,5-a]pyrimidine-3-carboxylate ( 3h ) showed the highest antioxidant activity [Half-maximal Inhibitory Concentration (IC50)=15.34 μM] compared to ascorbic acid (IC50=13.53 μM) as a standard compound. Their antibacterial activities were investigated against two Gram-positive bacteria (Bacillus subtilis, and Staphylococcus aureus) and two Gram-negative bacteria (Pseudomonas aeruginosa, and Escherichia coli). The results showed that Ethyl 7-hydroxy-5-phenylpyrazolo[1,5-a]pyrimidine-3-carboxylate ( 3i ) has the best antibacterial activity against Gram-positive B. subtilis [Zone of Inhibition (ZOI)=23.0±1.4 mm, Minimum Inhibitory Concentration (MIC)=312 μM]. Also, the cytotoxicity of these compounds was assessed against breast cancer cell lines [human breast adenocarcinoma (MCF-7)], which 7-Hydroxy-2-methyl-5-phenylpyrazolo[1,5-a]pyrimidine-3-carbonitrile ( 3f ) displayed the most cytotoxicity (IC50=55.97 μg/mL), in contrast with Lapatinib (IC50=79.38 μg/mL) as a known drug.  相似文献   
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