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排序方式: 共有207条查询结果,搜索用时 46 毫秒
111.
Masoud Sadeghzadeh Maryam Salahinejad Nahid Zarezadeh Mehdi Ghandi Maryam Keshavarz Baghery 《Molecular diversity》2017,21(4):821-830
In current study, antitumor activity of two series of the newly synthesized spiropyrroloquinoline isoindolinone and spiropyrroloquinoline aza-isoindolinone scaffolds was evaluated against three human breast normal and cancer cell lines (MCF-10A, MCF-7 and SK-BR-3) and compared with cytotoxicity values of doxorubicin and colchicine as the standard drugs. It was found that several compounds were endowed with cytotoxicity in the low micromolar range. Among these two series, compounds 6i, 6j, 6k and 7l, 7m, 7n, 7o containing 3-ethyl-1H-indole moiety were found to be highly effective against both cancer cell lines ranging from \(0.080 \pm 0.001\) to \(11.91 \pm 1.39\,\upmu \hbox {M}\) in comparison with the corresponding analogs. Compared with human cancer cells, the most potent compounds did not show high cytotoxicity against human breast normal MCF-10A cells. Generally, most of the evaluated compounds 6a–l and 7a–o series showed more antitumor activity against SK-BR-3 than MCF-7 cells. Moreover, comparative molecular field analysis (CoMFA) as a popular tools of three-dimensional quantitative structure–activity relationship (3D-QSAR) studies was carried out on 27 spiropyrroloquinolineisoindolinone and spiropyrroloquinolineaza-isoindolinone derivatives with antitumor activity against on SK-BR-3 cells. The obtained CoMFA models showed statistically excellent performance, which also possessed good predictive ability for an external test set. The results confirm the important effect of molecular steric and electrostatic interactions of these compounds on in vitro cytotoxicity against SK-BR-3. 相似文献
112.
Hamid Aliyan Razieh Fazaeli Nahid Fazaeli Ahmad Reza Mssah Hamid Javaherian Naghash Mohammad Alizadeh Ginous Emami 《Heteroatom Chemistry》2009,20(4):202-207
Rapid and efficient condensation reactions of o‐phenylenediamine and o‐aminothiophenol with various aldehydes were carried out using tungstophosphoric acid impregnated zirconium phosphate in solvent‐free conditions to afford the corresponding 2‐substituted arylbenzimidazole and arylbenzothiazole derivatives in good to excellent yields. This procedure constitutes a simple and practical green synthetic method for 2‐arylbenzimidazoles and 2‐arylbenzothiazoles and their structural analogs. Furthermore, the catalyst can be reused for several times but it will be less active. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:202–207, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20534 相似文献
113.
Ali Akbar Moshfegh Behnaz Mazandarani Azarmidokht Nahid Gholam Hosein Hakimelahi 《Helvetica chimica acta》1982,65(4):1229-1232
A short synthesis of the title compounds is reported. Most of the compounds prepared were found to be active against a number of pathogenic microorganisms in vitro. 相似文献
114.
One‐Pot Synthesis of Cu2O/ZnO Nanoparticles at Present of Folic Acid to Improve UV‐Protective Effect of Cotton Fabrics 下载免费PDF全文
Seyyed Abbas Noorian Nahid Hemmatinejad Azadeh Bashari 《Photochemistry and photobiology》2015,91(3):510-517
In this study, the effect of using folic acid on the in situ synthesis process of nanostructures has been investigated. Folic acid, as a biotemplate for synthesis of Cu2O/ZnO, was used to improve the reducing and stabilizing the ability of cotton fabric and avoid agglomeration of the particles. Scanning electron microscopy images revealed that using folic acid caused the formation of particles with smaller sizes on the cotton fabric and X‐ray diffraction confirmed the same crystalline pattern of nanoparticles in comparison with the previous synthesis process. The effect of using this biotemplate on different properties of treated fabrics including UV‐protection effect, hydrophilicity, crease recovery angle, softness, thickness and mechanical properties has been evaluated. The folic acid had a great influence on UV‐protection effect, in synthesis procedure, decreasing the droplet absorption time, bending length and improving the wrinkle resistance and mechanical properties. Interestingly, the higher tensile strength of the treated cotton fabrics proved the incorporation of nanoparticles into the cotton fibers. An in situ, green and rapid method can be provided by using folic acid for the synthesis of the nanostructures with controlled size. 相似文献
115.
Behrouz Shaabani Ali Akbar Khandar Nahid Ramazani Michel Fleck Haedeh Mobaiyen 《Journal of Coordination Chemistry》2017,70(4):696-708
A tridentate NNO donor hydrazine Schiff base, HL, was obtained from condensation of pyridine 2-carbaldehyde and 4-hydroxy benzohydrazide. HL and azide ligands with Cr(III), Mn(II) and Fe(III) have been used to synthesize [Cr(L)(N3)(OCH3)]2 (1), [Mn(HL)2(N3)2] (2), and [Fe(L)(N3)(OCH3)]2·H2O (3). HL is quite diverse in its chelating ability and can be a neutral or monoanionic ligand as a tridentate unit. In this paper, we report structures showing different denticities of the ligand having different charges. The ligand 1–3 was characterized by elemental analysis, FT-IR, and UV–vis spectral studies and solid-state structures were determined by single-crystal X-ray diffraction analysis, revealing that 1 and 3 are binuclear, while 2 is mononuclear. The efficiencies of the ligand and the three complexes were evaluated for antimicrobial activity; MIC data revealed that HL 1–3 are not strongly active in comparison to standard drugs. 相似文献
116.
Shima JANDAGHI Nahid TAHAN Alireza AKBARZADEH BAGHBAN Maryam ZOGHI 《Physical Therapy Research》2021,24(3):211
Objective: Several strategies have been designed to improve balance after stroke. Although recent studies have suggested that the balance training in stroke should include exercises that are performed in different sensory conflict conditions, little attention has been paid to manipulation of visual input. This study aimed to compare effects of balance training on an unstable surface with balance training under visual deprivation conditions in persons with stroke. Method: Forty-five stroke patients were randomized into three groups: the visual deprivation- stable based training (VD-SBT); unstable based training (UBT); and control (C) groups. Subjects of the VD-SBT group performed balance training on a stable surface with closed eyes. The UBT group performed balance training on an unstable surface with open eyes. Patients were assessed before and after interventions for Timed Up and Go (TUG), Four Square Step (FSS) and Five Times Sit to Stand (FTSS) tests. Result: There was a significant difference in pre- post intervention time of TUG, FSS and FTSS tests in all three groups. In a comparison of three groups, the UBT and VD-SBT groups had a significant improvement in time of all tests but significant improvement in time of all tests was observed in the VD-SBT group in comparison with the UBT group. In the field of balance training, the manipulation of visual input was more effective than the manipulation of standing surface to reweighting the sensory information. Conclusion: We recommended balance rehabilitation programs after stroke performed under conditions to stimulate the use of underused sensory input. 相似文献
117.
The scope of this article is to reveal the fruitful combination of POM species with metal coordination complexes, leading to the construction of several efficient multifunctional catalysts. In this review, we try to underscore various catalytic and photocatalytic reactions catalyzed by POM‐based inorganic‐organic hybrid. Notably, it has been well established that depending on the type of the reaction, the activity and selectivity of these hybrid catalyst can be drastically improved by the rational and correct choice of the organic metal complex and POM anion providing a marriage of convenience. 相似文献
118.
A simple and versatile procedure for the combinatorial synthesis of (Z)-dialkyl-5-(alkylimino)-5Hspiro[ furan-2,11'-indeno[1,2-b]quinoxaline]-3,4-dicarboxylates via the catalyst-free one-pot fourcomponent reaction of ninhydrin, benzene-1,2-diamines, dialkyl acetylenedicarboxylates and isocyanides is described. 相似文献
119.
The present study reports the synthesis of Co(II), Ni(II), Mn(II), Cu(II), and Zn(II) complexes with a new macrocyclic ligand (L2)- 1,2,8,9,11,14-hexaazacyclopentadeca-12,13-dioxo-10,15-dithione-2,7-diene. The macrocycle was derived from thiosemicabazone (L1) and diethyloxalate that were prepared by the reaction of thiosemicarbazide and glutaraldehyde in the ratio of 2:1. The synthesized complexes and ligands were characterized by elemental analysis and molar conductance, magnetic susceptibility, 1HNMR, IR, electronic, and thermogravimetric analyses. The molar conductance values confirmed that the Ni(II), Cu(II), Zn(II), Mn(II) and Co(II) complexes were 1:2 electrolytes. On the basis of electronic spectral studies and molar conductance measurements, the authors proposed an octahedral structure for Ni(II), Mn(II), and Co(II) complexes, tetrahedral geometry for Zn(II) complex, and square planar geometry for Cu(II) complex. The thermal behavior of the compounds was studied by TGA in a nitrogen atmosphere up to 750°C at the rate of 20°C/min. The TGA results revealed that the complexes had higher thermal stability than the macrocycle. All the synthesized compounds were screened against 4 bacteria (i.e., Streptococcus aureus, Escherichia coli, Bacillus subtillis, Salmonella typhimurium) and 2 fungi (i.e., Fusarium oryzae, Candida albicans). The results showed that the metal complexes inhibited the growth of bacteria to a greater extent as compared to the ligand. 相似文献
120.
Nahid Mashkouri Najafi Hamed Tavakoli Yaser Abdollahzadeh Reza Alizadeh 《Analytica chimica acta》2012
Herein, ultrasound-assisted emulsification microextraction (USAEME) and dispersive liquid–liquid microextraction (DLLME) methods based on applying low-density organic solvents have been critically compared for the speciation of inorganic selenium, Se(IV) (selenite) and Se(VI) (selenate) in environmental water samples by gas chromatography-flame ionization detection (GC-FID). At pH 2 and T = 75 °C for 7 min, only Se(IV) was able to form the piazselenol complex with 4-nitro-o-phenylenediamine. Piazselenol was extracted using an extraction solvent and was injected into a GC-FID instrument for the determination of Se(IV). Conveniently, Se(VI) remained in the aqueous phase. Total inorganic selenium was determined after the reduction of Se(VI) to Se(IV) and prior to the above procedures. The Se(VI) concentration was calculated as the difference between the measured total inorganic selenium and Se(IV) content. The effect of various experimental parameters on the efficiencies of the two methods and their optimum values were studied with the aid of response surface methodology and experimental design. Under the optimal conditions, the limit of detections (LODs) for Se(IV) obtained by USAEME-GC-FID and DLLME-GC-FID were 0.05 and 0.11 ng mL−1, respectively. The relative standard deviations (RSDs, n = 6) for the measurement 10 ng mL−1 of Se(IV) were 5.32% and 4.57% with the enrichment factors of 2491 and 1129 for USAEME-GC-FID and DLLME-GC-FID, respectively. Both methods were successfully applied to the analysis of inorganic selenium in different environmental water samples and certified reference material (NIST SRM 1643e). 相似文献