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801.
Bhattacharjee Maitri Boruah Smriti Rekh Dutta Purkayastha R. N. Maniukiewicz Waldemar Chowdhury Shubhamoy Maiti Debasish Akhtar Tamanna 《无机化学学报》2024,40(7):1409-1422
以甲醇为介质,合成了3种新的席夫碱配体HL1(2-hydroxybenzaldehyde2-(2-oxo-1,2-diphenylethylidene)hydrazone)、HL2(4-hydroxybenzaldehyde2-(2-oxo-1,2-diphenylethylidene)hydrazone)和 L3(2-methoxybenzaldehyde2-(2-oxo- 1,2-diphenylethylidene)hydrazone)的Cu(Ⅱ)配合物1~3。通过元素分析、光谱方法、磁化率测量和密度泛函理论(DFT)计算对配合物进行了表征。通过单晶X射线衍射研究对合成的配体进行了结构表征。通过DFT计算确定了配合物的优化结构。通过紫外可见吸收光谱和荧光发射光谱研究了配合物与小牛胸腺DNA(CT-DNA)的结合能力。吸收光谱研究揭示了增色效应,并提出了与CT-DNA相互作用的可能模式。溴化乙锭(EB)竞争结合研究表明,配合物可以取代 DNA-EB 加合物中的 DNA,且配合物可能以嵌入模式与 CT-DNA结合。配合物对革兰氏阴性肺炎克雷伯菌、大肠杆菌、鲍氏志贺菌和革兰氏阳性金黄色葡萄球菌的体外抗菌活性研究表明,配合物2对肺炎克雷伯菌和鲍氏志贺菌具有明显抗菌活性,但配合物1和3没有表现出任何显著的抗菌活性。 相似文献
802.
Henry T. G. Walsgrove Khadiza K. Chowdhury Philipp Dabringhaus Dr. Brian O. Patrick Prof. Dr. Derek P. Gates 《欧洲无机化学杂志》2023,26(20):e202300182
The anionic polymerization of 1-phosphaisoprene [Mes*P=C(Me)−CH=CH2 (E- 1 )] affords poly(1-phosphaisoprene) 2 in high yield (75 %). Concentrated solutions of polymer 2 (Mn=21,800 g mol−1; Đ=1.02) a P-analogue of natural rubber, undergo gelation upon treatment with [Pd(cod)Cl2] (0.15 P equiv). Evidence for P-coordination of 2 to PdII was obtained by 31P and 1H NMR spectroscopy. The gelation is reversed by the addition of PMe3 and the reformation of recoverable 2 along with [PdII−PMe3] complexes were confirmed by 31P NMR spectroscopy. The use of labile metal-ligand bonds to reversibly form gels is unprecedented and has relevance to self-healing materials. In contrast, coordination of 2 to [Pd(η3-C3H5)(μ-Cl)]2 affords the well-defined complex 2 ⋅ [Pd(η3-C3H5)Cl] which was characterized by 31P, 1H, 13C{1H} NMR spectroscopy and GPC. This polymer chemistry was complemented by detailed molecular model studies of the coordination chemistry of monomer 1-phosphaisoprene E- 1 with [Pd(cod)Cl2] and [Pd(η3-C3H5)(μ-Cl)]2]. 相似文献
803.
Karthikraja Esackraj Dr. Naga Venkateswara Rao Nulakani Dr. Venkata Surya Kumar Choutipalli Dr. Chandra Chowdhury Dr. Palanichamy Murugan Dr. V. G. Vaidyanathan Prof. Venkatesan Subramanian 《Chemphyschem》2023,24(11):e202300035
Generally, graphynes have been generated by the insertion of acetylenic content (−C≡C−) in the graphene network in different ratios. Also, several aesthetically pleasing architectures of two-dimensional (2D) flatlands have been reported with the incorporation of acetylenic linkers between the heteroatomic constituents. Prompted by the experimental realization of boron phosphide, which has provided new insights on the boron-pnictogen family, we have modelled novel forms of acetylene-mediated borophosphene nanosheets by joining the orthorhombic borophosphene stripes with different widths and with different atomic constituents using acetylenic linkers. Structural stabilities and properties of these novel forms have been assessed using first-principles calculations. Investigation of electronic band structure elucidates that all the novel forms show the linear band crossing closer to the Fermi level at Dirac point with distorted Dirac cones. The linearity in the hole and electronic bands impose the high Fermi velocity to the charge carriers close to that of graphene. Finally, we have also unravelled the propitious features of acetylene-mediated borophosphene nanosheets as anodes in Li-ion batteries. 相似文献
804.
Over the past two decades, it has become abundantly clear that nucleic acid biochemistry, especially with respect to RNA, is more convoluted and complex than previously appreciated. Indeed, the application and exploitation of nucleic acids beyond their predestined role as the medium for storage and transmission of genetic information to the treatment and study of diseases has been achieved. In other areas of endeavor, utilization of nucleic acids as a probe molecule requires that they possess a reporter group. The reporter group of choice is often a luminophore because fluorescence spectroscopy has emerged as an indispensable tool to probe the structural and functional properties of modified nucleic acids. The scope of this review spans research done in the Hudson lab at The University of Western Ontario and is focused on modified pyrimidine nucleobases and their applications as environmentally sensitive fluorophores, base discriminating fluorophores, and in service of antisense applications as well as tantalizing new results as G-quadruplex destabilizing agents. While this review is a focused personal account, particularly influential work of colleagues in the chemistry community will be highlighted. The intention is not to make a comprehensive review, citations to the existing excellent reviews are given, any omission of the wonderful and impactful work being done by others globally is not intentional. Thus, this review will briefly introduce the context of our work, summarize what has been accomplished and finish with the prospects of future developments. 相似文献
805.
Dr. Irene Regeni Rituparno Chowdhury Kai Terlinden Dr. Shinnosuke Horiuchi Dr. Julian J. Holstein Dr. Sascha Feldmann Prof. Dr. Guido H. Clever 《Angewandte Chemie (International ed. in English)》2023,62(40):e202308288
A strategy to engineer the stacking of diketopyrrolopyrrole (DPP) dyes based on non-statistical metallosupramolecular self-assembly is introduced. For this, the DPP backbone is equipped with nitrogen-based donors that allow for different discrete assemblies to be formed upon the addition of Pd(II), distinguished by the number of π-stacked chromophores. A Pd3L6 three-ring, a heteroleptic Pd2L2L′2 ravel composed of two crossing DPPs (flanked by two carbazoles), and two unprecedented self-penetrated motifs (a Pd2L3 triple and a Pd2L4 quadruple stack), were obtained and systematically investigated. With increasing counts of stacked chromophores, UV/Vis absorptions red-shift and emission intensities decrease, except for compound Pd2L2L′2, which stands out with an exceptional photoluminescence quantum yield of 51 %. This is extraordinary for open-shell metal containing assemblies and explainable by an intra-assembly FRET process. The modular design and synthesis of soluble multi-chromophore building blocks offers the potential for the preparation of nanodevices and materials with applications in sensing, photo-redox catalysis and optics. 相似文献
806.
807.
Harnessing new materials for developing high-energy storage devices set off research in the field of organic supercapacitors. Various attractive properties like high energy density, lower device weight, excellent cycling stability, and impressive pseudocapacitive nature make organic supercapacitors suitable candidates for high-end storage device applications. This review highlights the overall progress and future of organic supercapacitors. Sustainable energy production and storage depend on low cost, large supercapacitor packs with high energy density. Organic supercapacitors with high pseudocapacitance, lightweight form factor, and higher device potential are alternatives to other energy storage devices. There are many recent ongoing research works that focus on organic electrolytes along with the material aspect of organic supercapacitors. This review summarizes the current research status and the chemistry behind the storage mechanism in organic supercapacitors to overcome the challenges and achieve superior performance for future opportunities. 相似文献
808.
Yiru Ye Dr. Edy Abou-Hamad Dr. Xuan Gong Dr. Tuiana B. Shoinkhorova Dr. Abhay Dokania Prof. Jorge Gascon Dr. Abhishek Dutta Chowdhury 《Angewandte Chemie (International ed. in English)》2023,62(24):e202303124
Decarbonizing the transportation sector is among the biggest challenges in the fight against climate change. CO2-neutral fuels, such as those obtained from renewable methanol, have the potential to account for a large share of the solution, since these could be directly compatible with existing power trains. Although discovered in 1977, the zeolite-catalyzed methanol-to-gasoline (MTG) process has hardly reached industrial maturity, among other reasons, because maximizing the production of gasoline range hydrocarbons from methanol has proved complicated. In this work, we apply multimodal operando UV/Vis diffuse reflectance spectroscopy coupled with an online mass spectrometer and “mobility-dependent” solid-state NMR spectroscopy to better understand the reaction mechanism over zeolites H-Beta and Zn-Beta. Significantly, the influential co-catalytic role of oxymethylene species is linked to gasoline formation, which impacts the MTG process more than carbonylated species. 相似文献
809.
Pahari Debanjana Chowdhury Arghadeep Das Dhrubajyoti Paul Tanmoy Puravankara Sreeraj 《Journal of Solid State Electrochemistry》2023,27(8):2067-2082
Journal of Solid State Electrochemistry - Solid-state synthesis of novel electrode materials of P2-type layered oxides Na0.67Ni0.33-xVxMn0.67O2 (where x = 0, 0.05, and 0.11) for the... 相似文献