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排序方式: 共有128条查询结果,搜索用时 15 毫秒
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Jabeen  M.  Ali  S.  Shahzadi  S.  Shahid  M.  Sharma  S. K.  Qanungo  K. 《Russian Journal of General Chemistry》2017,87(3):530-538
Russian Journal of General Chemistry - Vanadium(IV) and vanadium(V) complexes 1–7 have been synthesized by the reaction of isonipecotic acid with VOSO4 · 3 H2O, VCl3(THF)3, and NH4VO3 at...  相似文献   
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New dichloro zinc(II) complex ligated by the homochiral bidentate ligand S-1-phenyl-N-(S-pyrrolidin-2-ylmethyl)ethanamine (PPMA) was synthesized and characterized by X-ray crystallography. The geometry of the (PPMA)ZnCl2 is a distorted tetrahedron comprising of zinc metal as a center linked with two N atoms of the PPMA in a bidentate coordination mode along with two chloro ligands. The catalytic capacity of the complex was evaluated in ring opening polymerization (ROP) of rac-lactide. The active catalyst species was generated in situ by treating MeLi to complex (PPMA)ZnCl2. The dimethyl derivative of the (PPMA)ZnCl2 showed highly activity in ROP of rac-lactide and gave preference to heterotactic polylactide.  相似文献   
86.
A new pregnane derivative, 2,6beta,7beta-trihydroxy-4-methyl-19-norpregna-1,3,5(10)-trien-17-one, has been isolated from the ethyl acetate soluble fraction of Potentilla evestita along with a pregnane derivative, 11alpha,17alpha,21-trihydroxypregna-4,16(22)-diene-3,20-dione, that is reported for the first time as a natural product. Their structures were elucidated with the aid of 1H and 13C NMR spectra and by COSY, HMQC, HMBC and NOESY experiments.  相似文献   
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Abstract

The present study reports ecofriendly synthesis of CuO nanoparticles (NPs) using an extract of Rhus punjabensis as a reducing agent. NPs structural and composition analysis are evaluated by X-rays diffraction (XRD), Fourier transform infrared, Energy dispersive spectroscopy, Scanning electron microscopy, Transmission electron microscopy, and Thermal analysis. The NPs have pure single phase monoclinic geometry with spherical structure and high stability toward heat and with average particle size of about 36.6 and 31.27?nm calculated by XRD and SEM, respectively. NPs are tested for antibacterial, protein kinase (PK) inhibition, SRB cytotoxic, and NF-κB activities. Antibacterial activity is observed against B. subtilis and E. coli. Significant PK and SRB cytotoxic activity is observed with some NF-κB inhibition. NPs IC50 values against HL-60 and PC-3 prostate cancer cells are 1.82?±?1.22 and 19.25?±?1.55?μg/mL. The results encourage further studies for antibacterial and anticancer drug development of NPs using animal models.  相似文献   
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4-(Hydroxymethyl)piperidine-1-carbodithioic acid has been synthesized by reacting 4-piperidinemethanol with carbon disulfide at room temperature. The synthesized ligand was treated with organotin(IV) chlorides to yield organotin complexes. These complexes by further treatment with palladium chloride afford heterobimetallic complexes containing Sn(IV) and Pd(II). The synthesized complexes along with ligand has been characterized by elemental analysis, FTIR, NMR (1H, 13C) spectroscopy. The IR data confirmed the complexation through the sulfur and oxygen donor sites of the ligand. NMR data revealed the tetrahedral geometry in the solution. Biological activity was checked against selected bacterial and fungal strains. All complexes along with the ligand were found to be biologically active with few exceptions.  相似文献   
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Dimethytin(IV) S(+)-2-(4-isobutylphenyl)propanoate was synthesized and characterized by elemental analysis and IR and variable temperature NMR spectroscopy. Variable temperature NMR analysis was performed to see the effect of temperature on coordination geometry of organotin complexes in non-coordinating solvent. Spectral data has shown that temperature change does not alter the coordination geometry of the complex, and that it remains greater than four at variable temperatures as well as at room temperature in solution state. This text was submitted by the authors in English.  相似文献   
90.
就微型平行板间的非Newton流体,给出了其随时间周期电渗流动的精确解.在数学公式化中,利用了广义Burgers流体的构成方程.按Fourier变换方法求解了所得到的问题.最后,用图形画出并讨论了所关注参数的不同变化.  相似文献   
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