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71.
The binding behavior of triphenylene based copper ensemble prepared in situ has been investigated toward various anions (F(-), Cl(-), Br(-), I(-), CH(3)COO(-), H(2)PO(4)(-), NO(3)(-), OH(-), ClO(4)(-), CN(-), CO(3)(-) and SO(4)(-)) by UV-vis and fluorescence spectroscopy. Among various anions tested, 1-Cu(2+) ensemble shows selective and sensitive response towards cyanide ions and responds to CN(-) ions even in the presence of bovine serum albumin and in blood serum milieu. Further, as practical application of compound 1, we utilized the TLC strips coated with THF solution of 1 for the solid state detection of copper and cyanide ions. 相似文献
72.
Kumar M Kumar R Bhalla V Sharma PR Kaur T Qurishi Y 《Dalton transactions (Cambridge, England : 2003)》2012,41(2):408-412
A thiacalix[4]arene based fluorescent chemosensor 3 in the cone conformation has been synthesized and its recognition behaviour is evaluated toward various metal ions in mixed aqueous media. The chemosensor 3 showed high selectivity towards Fe(3+) ions by fluorescence quenching of excimer emission. Further, evaluation of the 3·Fe(3+) complex prepared in situ demonstrated great promise for the detection of the Fe(3+) ion in the presence of amino acids, blood serum and bovine serum albumin (BSA) solution. The compound 3 has suitable permeability into the PC3 cells and can be utilized as a Fe(3+) selective sensor in living cells (PC3 cells). 相似文献
73.
Jai V. Jaiswal Prasad A. Wadegaonkar Sunil W. Hajare 《Applied biochemistry and biotechnology》2012,167(5):1325-1339
Bioflavonoids are plant compounds touted for their potential to treat or prevent several diseases including cancer caused by various stress conditions. Galangin (4H-1-Benzopyran-4-one, 3, 5, 7-trihydroxy-2-phenyl-), a flavonoid, is a polyphenolic compound found primarily in medicinal herb, Alpinia galanga. This study aims to demonstrate the galangin as a pharmacological lead compound using in vitro, in vivo, and in silico model targeting specific cancer condition and proteins. The proliferation of MCF-7 and Ehrlich ascites carcinoma (EAC) cells was significantly inhibited with an IC50 of 34.11 and 22.29???g/ml, respectively. In an animal model system, galangin has inhibited the tumor growth by 73.51%?±?4.742 in EAC-induced Swiss Albino mice with no evidences of mortality as compared to standard drug, 5-fluorouracil. The effectiveness of galangin is proven in an animal system suggesting its pharmacokinetics behavior in an animal model which is also complemented by outcome of in silico analysis with more than 88?% of human intestinal absorption and significant Caco-2 cell, MDCK cell, and skin permeability as predicted by in silico methods. Galangin was docked against 19 different proteins involved in tumorogenesis and apoptosis; the energetic analysis indicates that it exhibits higher predicted binding free energy of ?12.7?kcal/mol with Bcl-xL protein. 相似文献
74.
Gourab Chatterjee Ajay Jha Alejandro Blanco-Gonzalez Vandana Tiwari Madushanka Manathunga Hong-Guang Duan Friedjof Tellkamp Valentyn I. Prokhorenko Nicolas Ferr Jyotishman Dasgupta Massimo Olivucci R. J. Dwayne Miller 《Chemical science》2022,13(32):9392
The concerted interplay between reactive nuclear and electronic motions in molecules actuates chemistry. Here, we demonstrate that out-of-plane torsional deformation and vibrational excitation of stretching motions in the electronic ground state modulate the charge-density distribution in a donor-bridge-acceptor molecule in solution. The vibrationally-induced change, visualised by transient absorption spectroscopy with a mid-infrared pump and a visible probe, is mechanistically resolved by ab initio molecular dynamics simulations. Mapping the potential energy landscape attributes the observed charge-coupled coherent nuclear motions to the population of the initial segment of a double-bond isomerization channel, also seen in biological molecules. Our results illustrate the pivotal role of pre-twisted molecular geometries in enhancing the transfer of vibrational energy to specific molecular modes, prior to thermal redistribution. This motivates the search for synthetic strategies towards achieving potentially new infrared-mediated chemistry.Channelling vibrational excitation energy to achieve ground-state charge-transfer (CT)-assisted isomerization in a donor-bridge-acceptor molecule in solution. 相似文献
75.
76.
Shyam Sundar Mondal Namita Jaiswal Partha Sarathi Bera Ranjay K. Tiwari Jogendra Nath Behera Nripen Chanda Subhas Ghosal Tanmoy Kumar Saha 《应用有机金属化学》2021,35(1)
A series of copper (II) ( 1 and 3 ) and cobalt (II/III) ( 2 , 4 and 5 ) complexes comprising different imino‐phenolate ligands DCH , DTH and DBH 2 (where DCH = 2,4‐dichloro‐6‐((mesitylimino)methyl)phenol, DTH = 2,4‐di‐tert‐butyl‐6‐((mesitylimino)methyl) phenol and DBH 2 = 2,4‐dibromo‐6‐((mesitylimino)methyl)phenol) have been prepared with excellent yield and high purity. By utilizing different spectroscopic tools such as UV–visible, electrospray ionization (ESI)‐mass, Fourier‐transform infrared (FTIR) spectrometry and elemental analysis, the prepared complexes ( 1 – 5 ) were thoroughly characterized. The molecular structure of the synthesized complexes was ascertained by using single‐crystal X‐ray diffraction studies (SCXRDs). The experiment reveals that Complexes 1 – 5 bind to calf thymus DNA (CT‐DNA) through non‐intercalative way with good interacting abilities. However, 1 – 5 are excellent quenchers of the fluorescence intensity of bovine serum albumin (BSA) following the static pathway. Additionally, they had shown remarkable cytotoxic potential against MCF‐7 (mammary gland adenocarcinoma) and A549 (lung adenocarcinoma) cell lines. The IC50 values associated with these complexes were much lower than the conventional drug cisplatin. Apoptosis‐induced cell death was confirmed from the DNA fragmentation studies and Hoechst 33342 staining. The 2′,7′‐dichlorofluorescein diacetate (DCFDA) assay indicates that the complex mediated reactive oxygen species (ROS) generation is accountable for governing the apoptosis mechanism via oxidative cell distress. Apart from these studies, by carrying out density functional theory (DFT) method, highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) energy gap calculations and optimized structures of the synthesized complexes were accomplished. 相似文献
77.
Rupak Mukherjee Surabhi Jaiswal Manish K. Shukla Ammar Hakim Edward Thomas 《等离子体物理论文集》2020,60(4):e201900161
A new concept called “configurational temperature” is introduced in the context of dusty plasma, where the temperature of the dust particles submerged in the plasma can be measured directly from the positional information of the individual dust particles and the interaction potential between the dust grains. This method does not require the velocity information of individual particles, which is a key parameter to measure the dust temperature in the conventional method. The technique is initially tested using two-dimensional (2D) OpenMP parallel molecular dynamics and Monte Carlo simulation and then compared with the temperature evaluated from experimental data. The experiment have been carried out in the Dusty Plasma Experimental (DPEx) device, where a 2D stationary plasma crystal of melamine formaldehyde particles is formed in the cathode sheath of a DC glow discharge argon plasma. The kinetic temperature of the dust is calculated using the standard particle image velocimetry technique at different pressures. An extended simulation result for the three-dimensional case is also presented, which can be employed for the temperature measurement of a three-dimensional dust crystal in laboratory devices. 相似文献
78.
79.
The intermittency effect has been observed in interactions of 800 GeV protons with emulsion-nuclei in one-(pseudorapidity/azimuthal angle) and two-dimensional (pseudorapidity and azimuthal angle) phase spaces in different multiplicity intervals. The intermittency strength is found to decrease with increasing multiplicity. Compared to one dimension, the two dimensional distribution is found to reflect better the intermittent behavior of the interactions. The dependence of various intermittency parameters on order of moment gives clear evidence of self-similar cascade mechanism in the interactions but there is no definite indication of the presence of different phases in the cascade. 相似文献
80.
Pradeep K. Muwal Aradhana Nayal Manish K. Jaiswal Pramod S. Pandey 《Tetrahedron letters》2018,59(1):29-32
A novel dipyrromethane based receptor has been synthesized. It works as a highly selective colorimetric sensor for F? and Cu2+ ions, which can be used for their necked eye detection with evident colour change of its solution. 相似文献