Synthesis,crystal structures,and antibacterial activities of two zinc(Ⅱ) complexes bearing 5⁃phenyl⁃1H⁃pyrazole group

A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(2)(L)_(2)(HL)_(2)(NCS)_(2)]_(2)·2CH_(3)OH(2)have been synthesized by the coordination reactions of Zn(OAc)_(2)·2H_(2)O or ZnCl_(2)with(H_(2)L)SCN under reflux conditions.Elemental analyses and single⁃crystal X⁃ray diffraction have con⁃firmed the structures of the synthesized compounds.The(H_(2)L)SCN ligand and complex 1 pertain to the triclinic sys⁃tem with space group P1,while complex 2 belongs to the monoclinic system with space group P2_(1)/n.Additionally,the antibacterial activities of the compounds were evaluated in vitro using the agar diffusion method against the bac⁃terial strains(Candida albicans,Staphylococcus aureus,and Escherichia coli).The results showed that the ligand exhibited relatively good antibacterial activities against the bacteria,and the complexes possessed stronger antibac⁃terial activities against the same bacteria than the free ligand.CCDC:2190252,(H2L)SCN;2190253,1;2190256,2.

A Mini-Review 5-Amino-N-Substituted Pyrazoles as Building Blocks for Bioactive Molecules

In this review a five-membered heterocyclic ring having two adjacent nitrogen atoms known as Pyrazole, we have framed 5-amino-N-substituted pyrazoles in particular focusing on its substantial role as a building block and starting materials for producing enormous heterocyclic skeletons. The existence of this moiety in larger compounds renders them to expose medicinal, pharmacological and biological therapeutic activities. Enormous drugs contain 5-amino-N-substituted pyrazoles such as celecoxib anti-inflammatory, antipsychotic, anti-obesity, analgesic, and antidepressant. We reported various routes of synthesis and the use of these compounds.

One-pot Synthesis of 2,5-Disubstituted Oxazoles Using Poly[styrene(iodosodiacetate)]

Disubstituted oxazoles were prepared conveniently by treatment of aromatic -methyl ketones and nitriles with poly[styrene(iodosodiacetate)] in one-pot process.

Synthesis and <i>in Vitro</i>Biological Activities of 4,5-Disubstituted 1,2,4-Triazole-3-Thiols

Purpose: The triazole nucleus is an important part of the therapeutically interesting drug candidate as antimicrobial, analgesic, anticancer, anticonvulsant and anti-inflammatory agents. Methods: Therefore, in this study, twelve 4,5-disubstituted-1,2,4-triazole-3-thiols were synthesized by the reaction of substituted isothiocyanates and hydrazides using the common method of base catalysed intramolecular dehydrative cyclization of substituted thiosemicarbazides 3(a-f) and 4(a-f). The structures of these compounds were characterized by means of FT-IR, 1H-NMR, and elemental analysis data. All these compounds were screened for antibacterial, antioxidant, antitumor and cytotoxic activities. Results: Among these compounds: 5c, 5f and 6f were found active against gram positive cocci, the compounds 5a, 5b, 5d, 6a and 6f showed 85% free radical scavenging effect at 3 ppm when tested for antioxidant activity, 75% tumors inhibition was recorded using 5c, 5d and 6a and brine shrimps lethality assay declared 5a, 5b and 6d was 129.62 μg/ml, 161.577 μg/ml and 81.56 μg/ml respectively. Conclusion: Compounds carrying significant bioactivity can be further studied using animal models to establish their safety profile prior to initiating clinical trials.

Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One

New cobalt(II) complex, [Co(O2C15H11N2S)2(OH2)2]∙2H2O (1∙2H2O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)2∙6H2O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H2O. Compound 1∙2H2O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H2O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H2O displayed moderate activity (10 ∙2H2O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).

SYNTHESIS OF 4,6-DISUBSTITUTED 5-THIOXO-1,2,4-TRIAZIN-3-ONE FROM BENZOTHIOFORMANILIDE

A method of synthesis of 4,6-disubstituted 5-thioxo-1,2,4-triazin- 3-ones from benzothioformanilides and semicarbazide is described.And six new compounds were synthesized by this method.

Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One

New cobalt(II) complex, [Co(O2C15H11N2S)2(OH2)2]∙2H2O (1∙2H2O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)2∙6H2O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H2O. Compound 1∙2H2O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H2O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H2O displayed moderate activity (10 ∙2H2O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).

Synthesis and Antibacterial Activities of 1,4-Disubstituted Phenyl-5-(halo-2-hydroxyphenyl)imino-1,2,3-triazole

According to the superposition principle of reinforcement of biological activities, 24 novel 1,4- disubstituted phenyl-5-（halo-2-hydroxyphenyl）imino-l,2,3-triazoles was synthesized and characterized by 1H NMR, ^13C NMR, elemental analysis and IR. All the target compounds were screened for their antibacterial potential in vitro against Monilia albican, Escherichia coli and Staphylococcus aureus. It was shown that all the compounds possessed efficient antibacterial activities at a concentration of 0.1 mg/mL, even at a concentration of 0.01 mg/mL, some of the compounds still exhibited antibacterial activities against Escherichia coli and Monilia albican. At last, the struc- ture-activity relationship was discussed based on the antibacterial results.

Key Intermediates: A Simple and Highly Selective Synthesis of 5-<i>Amino</i>-1-<i>aryl</i>-1<i>H</i>-<i>pyrazole</i>-4-<i>carbonitriles</i>for Applications in the Crop Protection

A series of six pyrazoles was synthesized by Michael-type addition reaction. The molecules 5-amino-1-aryl-1H-pyrazole-4-carbonitrile (3a-f) were synthesized from (ethoxymethylene)malo-nonitrile (1) and fluorinated and non-fluorinated aryl hydrazines (2a-f) using ethanol and fluorinated ethanol as solvents at reflux. An excellent regio-selectivity was found when pyrazole derivatives were formed as an exclusive product. No other regioisomer or uncyclised hydrazide was observed. Their structures were confirmed by spectroscopy data (1H, 13C, 19F, COSY (correlation spectroscopy), HSQC (heteronuclear single-quantum correlation spectroscopy) and HMBC (heteronuclear multiple-bond correlation spectroscopy);MS (mass-spectrometry). The yields ranged from good to excellent (47% - 93%) under mild reaction conditions. It would indicate a high selectivity in the one-step work procedure. These products (3a-f) and derivatives have a potential academic and industrial use as key intermediates, in special, for application in crop protection.

Greener approach towards the facile synthesis of 1,4-dihydropyrano[2,3-c]pyrazol-5-y1 cyanide derivatives at room temperature

This report describes triethylammonium acetate （TEAA） ionic liquid catalyzed one pot synthesis of 6-amino-4-aryl-5-cyano-3- methyl-1-phenyl-1,4-dihydropyrano [2,3-c]pyrazoles by the reaction of aromatic aldehyde, malononitrile and 3-methyl-1-phenyl-2- pyrazolin-5-one at room temperature. TEAA plays dual role as reaction media and catalyst. It can also be easily recovered and reused in several runs. TEAA provides greener reaction protocol to present methodology which obviates the need of organic solvents, expensive and toxic catalyst.

Synthesis and Crystal Structure of a Novel Ethyl 5-(4-(2-Phenylacetamido)phenyl)-1H-pyrazole-3-carboxylate as an Acrosin Inhibitor

The title compound （ethyl5-（4-（2-phenylacetamido）phenyl）-lH-pyrazole-3-carboxylate, C20H19N3O3） was synthesized by the reaction of Claisen condensation, cyclization, reduction and acylation. The structure was characterized by X-ray diffraction, MS, NMR and IR. It belongs to the monoclinic system, space group C2/c with a = 22.723（9）, b = 9.324（4）, c = 18.890（8） A, β = 114.259（6）°, V = 3649（3） A^3, Dc = 1.272 Mg·m^3, Z = 8, Mr = 349.38, p = 0.087 mm^-1, F（000） = 1472, the final R = 0.0615 and wR = 0.1643. The biological test shows that the title compound has a moderate acrosin inhibition activity.

Synthesis and Crystal Structure of Trans-4-[(5-(2,4-Dichlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one

The title compound trans-4-[（5-（2,4-dichlorophenoxy）-3-methyl- 1-phenyl-1H-pyrazol-4-yl）methyleneamino]- 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 （C28H23Cl2N5O2, Mr = 532.41） has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1- with a = 8.9438（4）, b = 11.6065（5）, c = 14.2215（6）A, α = 112.566（1）, β = 92.324（2）, γ = 102.91（1）°, V= 1315.65（10） A^3, Z = 2, Dc = 1.344 g/cm^3,μ（MoKa） = 0.282 mm^-1, λ = 0.71073 A, F（000） = 552, the final R = 0.0587 and wR = 0.1578 for 5071 observed reflections （I 〉 2σ（I））. X-ray analysis reveals that the product is a thermodynamically stable trans isomer. Intra- and intermolecular C（ 12）-H（12）…O（1） and C（28）-H（28）...O（1）# 1 hydrogen bonds were observed in the title compound.

Synthesis,Characterization and Antibacterial Activity of New 5-Aryl Pyrazole Oxime Ester Derivatives

Eleven new 1-{5-[4-（benzyloxy）phenyl]-3-methyl-4,5-dihydropyrazol-l-yl} oxime ester dcrivatives were synthesized and characterized by elemental analysis, HRMS, ^1H NMR data. All the compounds were screened for their antibacterial potential in vitro against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The results indicate that compounds 8c and 8f possess potent activity with the minimum inhibitory concentrations（MIC） of 1.562--3.125 ug/mL against all the four bacteria. Compounds 8c, 8e and 8f show moderate inhibition against the DNA gyrase（IC50=1.9--2.5 ug/mL）. On the basis of the biological activities, structure-activity relationship was discussed.

Synthesis and Crystal Structure of 5-Diazo-4-ethoxycarbonyl-3-methylthio Pyrazol

The crystal of the title compound, 5-diazo-4-ethoxycarbonyl-3-methylthio pyrazole, has been prepared and determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c with a = 29.174(8), b = 4.7592(12), c = 15.956(4) ? b = 117.632(4), C7H8N4O2S, Mr = 212.23, V = 1962.7(9) ?, Z = 8, Dx = 1.436 g/cm3, S = 1.000, m(MoKa) = 0.31 mm-1, T = 298(2) K, F(000) = 880, R = 0.0658 and wR = 0.1741 for 1091 independent reflections with I ≥ 2s(I). The crystal of the title compound is formed with p-p interactions through electrostatic attractions. Moreover, no HSO4- exists in the crystal structure. Therefore, only diazo pyrazole was obtained rather than either diazonium salt of the corresponding pyrazole or diazoaminopyrazole when 5-amino-4-ethoxycarbonyl-3-methylthio pyrazole was diazotized with sodium nitrite, catalyzed by sulfuric acid at 0 ℃.

Inhibition Mechanism of Novel Pyrazolo[1,5-a]pyrazin-4(5H)-one Derivatives Against Proliferation of A549 and H322 Cancer Cells

Objective To explore the inhibition mechanism and safety of pyrazolo[1,5-a]pyrazin-4(5H)-one derivatives against proliferation of human lung cancer A549 cells, H322 cells, and human umbilical vein endothelial cell(HUVEC). Methods Cells were treated with 40 μmol/L of the ppo3 a, ppo3 b, ppo3 i, and 0.1% DMSO(control) for 48 hours, respectively. Apoptosis was determined by Hoechst 33258 staining assay in H322 and A549 cells. Cell cycle distribution was determined by flow cytometry analysis in A549 cell. LC3-II, p53, and heat shock protein(HSP) 70 protein levels were detected by Western blotting in A549 cells treated with ppo3 b for 48 hours. The morphology and viability of HUVEC were observed by inverted microscope and sulforhodamine B(SRB) assay. Results Ppo3 a, ppo3 b, and ppo3 i significantly induced apoptosis in H322 and A549 cells. A strong G1-phase arrest was concomitant with the growth inhibitory effect on A549 cells. Ppo3 b effectively elevated the p53 protein level, but significantly reduced the HSP70 protein level. There were no significantly inhibitory effect on the morphology and viability of HUVEC when treated with ppo3 a, ppo3 b, and ppo3 i. Conclusions ppo3 a, ppo3 b, and ppo3 i could inhibit H322 proliferation through apoptosis and inhibit A549 through apoptosis and G1-phase arrest. The protein p53 and HSP70 might involve in the inhibition effects. These derivatives might be a clue to find effective and safe drug for lung cancers.

Use of Solid-Supported Reagents towards Synthesis of 2-Arylbenzoxazole, 3, 5-Diarylisoxazole and 1, 3, 5-Triarylpyrazole

Herein we report a convenient and efficient synthesis of 2-Arylbenzoxazole from the Schiff’s bases of 2-Aminophenol, 3, 5-Diarylisoxazole from α, β-unsaturated ketoxime and 1,3,5-Triarylpyrazole from 2-pyrazoline and N-Arylhydrazone by using milder, less toxic and less expensive-NBS-SiO2, KMnO4-Al2O3, PCC-SiO2 and ACC-Al2O3 as solid-supported oxidizing agents at room temperature. Within the framework of Green Chemistry, the use of solid supported reagents has many advantages such as 1) they are easy to remove from reactions by filtration 2) excess reagents can be used to drive the reaction without introducing any difficulties in purification 3) such solid-supported reagents react differently, mostly more selectively, than their unbound counterparts and 4) toxic, noxious and explosive chemicals are handled more safely when contained on solid support.

Aromatic Multicarboxylate Ligands Tuned One-and Three-dimensional Zn(Ⅱ) Coordination Polymers Based on 3-(1H-pyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole

Two aromatic multicarboxylate ligands tuned Zn(Ⅱ) coordination polymers, namely, {[Zn0.5(H2L)(tp)0.5(H2O)]H2O}n(1) and {[Zn2(HL)(btc)(H2O)]H2O}n(2)(H2L = 3-(1 Hpyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole, H2tp = terephthalic acid;H3 btc = 1,3,5-benzenetricarboxylic) have been synthesized. Their structures were characterized by single-crystal X-ray diffraction analysis, elemental analyses and infrared spectra. Compound 1 possesses a one-dimensional chain structure and is finally extended into a three-dimensional supramolecular architecture though hydrogen bonding interactions. Compound 2 shows a three-dimensional framework. Meanwhile, compounds 1 and 2 exhibit luminescent emission in the solid, and can be investigated as potential luminescent materials.

Two New Schiff Bases Based on 5-Chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde: Syntheses, Crystal Structures and Properties

Two new Schiff bases based on 5-chloro-3-methyl-1-phenyl-1 H-pyrazole-4-carbaldehyde, namely, N-((5-chloro-3-methyl-1-phenyl-1 H-pyrazol-4-yl)methylene)-4-morpholinoaniline(Ⅲa) and N-((5-chloro-3-methyl-1-phenyl-1 H-pyrazol-4-yl)methylene)-3-fluoro-4-morpholinoaniline(Ⅲb), were synthesized and characterized by IR, LC-MS, 1 H NMR and 13 C NMR spectroscopy. Meanwhile, the three-dimensional configurations of the two title compounds were further characterized by single-crystal X-ray diffraction analyses. Both the compounds are thermodynamically stable trans-isomers. Moreover, the fluorescence properties and antioxidant activities against DPPH of the two target compounds have been investigated, and the results showed that the title compounds both have fluorescence performance and certain antioxidant activities against DPPH radical.

Enamine Configuration of 5-Methyl-2-phenyl-4- [(Z)-3-tolylamino-phenylmethylene]pyrazol-3(2H)-one

Compound 5-methyl-2-phenyl-4-[（Z）-3-tolylamino-phenylmethylene]pyrazol-3（2H）-one （C24H21N3O） crystallizes in the triclinic system, space group P1, with a = 9.267（3）, b = 9.904（4）,c = 12.035（4） A°, α = 97.896（6）, β = 103.865（6）, γ = 107.950（6）°, Mr= 367.44, Z = 2, V = 993.2（6）A°^3,Dc = 1.229 g/cm^3,μ（MoKa） = 0.077 mm^-1 and F（000） = 388. The structure was refined to R =0.0444 and wR = 0.1199 for 2903 observed reflections （I 〉 2σ（I））. The results of ^1H NMR and single-crystal X-ray diffraction studies showed the enamine character of the compound. The strong intramolecular hydrogen bonds in the large conjugate system, together with weak intermolecular C-H……π hydrogen bonding and π……π stacking, lead to the formation of a multi-dimensional supramolecular network.

Extraction of Th(IV) from nitric acid with 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione

The BMPPT (4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione)was synthesized from BMPP. Its m.p. is 106-108℃. The results of the element analysis are as follows: C, 68.51%, H, 4.51%, N, 9.26%, S, 11.47%, which are in conformity with the theoretical value (C, 69.15%, H, 4.76%, N, 9.52%, S, 10.90%). The solvent extraction of Th4+ from nitric acid solution by BMPPT in benzene was studied. The extraction ability of BMPPT is not so high as that of its parent (BMPP). The Th4+ distribution ratio (DTh) increases with the increasing pH of the aqueous phase, and pH1/2 for Th4+ was 3.2 ([BMPPT]=0.10 mol/L). When the pH increases, the distribution ratio of Th4+ increases linearly with the slope of 1 .59. When the concentration of BMPPT increases, the distribution ratio of Th4+ increases rapidly. The lgDTh-lg[BMPPT] is linear with the slope of 1.42 and the extraction mechanism is the cation ion-exchange.