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991.
A new Cu(II) coordination polymer, {[Cu(1,3-BIP)(TFBDC)]·DMF}n(1,1,3-BIP is a 1,3-bis(imidazole)propane, and H2TFBDC is 2,3,5,6-tetrafluoroterephthalic acid) was prepared under solvothermal conditions and characterized by single-crystal and powder X-ray diffraction, IR spectra, thermogravimetric analyses and elemental analyses. The single-crystal X-ray diffraction reveals that metal coordination polymer 1(MCP 1) shows a two-dimensional sheet layer structure, which is further reinforced through strong intermolecular hydrogen bonding to form a 3 D supramolecular framework. Furthermore, the photocatalytic experiment result indicates the degradation ratios of methyl orange(MO) reach 83.4% within 180 minutes when MCP 1 acts as catalyst. 相似文献
992.
Sharma Deepika Radha Anu Kumar Pretam Kumar Sandeep Jassal Amanpreet K. Lata Suman Vikas Pandey Sushil K. 《Transition Metal Chemistry》2020,45(8):531-544
Transition Metal Chemistry - Nickel(II) complexes with octahedral coordination stabilized by N-donor ligands corresponds to [{(ArO)2PS2}2Ni·L2] [Ar = 4-(C2H5)C6H4 (3), and... 相似文献
993.
Márton Zwillinger Dr. Post Sai Reddy Dr. Barbara Wicher Dr. Pradeep K. Mandal Dr. Márton Csékei Dr. Lucile Fischer Dr. András Kotschy Prof. Dr. Ivan Huc 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(72):17366-17370
Helically folded aromatic oligoamide foldamers have a size and geometrical parameters very distinct from those of α-helices and are not obvious candidates for α-helix mimicry. Nevertheless, they offer multiple sites for attaching side chains. It was found that some arrays of side chains at the surface of an aromatic helix make it possible to mimic extended α-helical surfaces. Synthetic methods were developed to produce quinoline monomers suitably functionalized for solid phase synthesis. A dodecamer was prepared. Its crystal structure validated the initial design and showed helix bundling involving the α-helix-like interface. These results open up new uses of aromatic helices to recognize protein surfaces and to program helix bundling in water. 相似文献
994.
The N-heterocyclic carbene, imidazole-2-ylidene, and its main group (13-15) analogues contain cyclically conjugated 6π electrons. Experimental 1H nuclear magnetic resonance (NMR) spectra suggest an increase in aromaticity along a period from left to right. Whereas the order along a group is as follows: period 2 > period 5 > period 4 > period 3 due to change in structure. To understand the order of aromaticity, the magnetically induced ring currents of the molecules are calculated using aromatic ring current shielding, gauge-including magnetically induced currents (GIMIC) method and Stanger's σ-model applying the gauge-including atomic orbitals NMR technique. It is found that GIMIC best describes the order of aromaticity especially along a group where current-profile changes on the bivalent atom down a group due to change in electron density. Moreover, the GIMIC provides the visualization of current by sign modulus and the anisotropy of the induced current density plots. 相似文献
995.
Dharmendra Kumar Yadav Devesh Kumar Singh Vellaichamy Ganesan 《Current Opinion in Electrochemistry》2020
To decrease the global carbon footprint concerns and to diminish the energy crisis, electrocatalytic reduction of CO2 which results in the formulation of value-added chemicals is a potential solution. In this review, single-atom catalysts (SACs) which are rapidly growing and being developed as the stimulating catalytic materials for electrocatalytic reduction of CO2 with improved selectivity, efficiency, and stability are considered. Various factors which are responsible for the efficient CO2 reduction are discussed. The pyrolytic approach for the preparation of Ni-based SACs and the maximum atom utilization efficiency for the desirable production of CO from CO2 are highlighted. 相似文献
996.
Saurav Goel Sara Hawi Gaurav Goel Vijay Kumar Thakur Anupam Agrawal Clare Hoskins Oliver Pearce Tanvir Hussain Hari M. Upadhyaya Graham Cross Asa H. Barber 《Materials Today Chemistry》2020
The world is witnessing tumultuous times as major economic powers including the US, UK, Russia, India, and most of Europe continue to be in a state of lockdown. The worst-hit sectors due to this lockdown are sales, production (manufacturing), transport (aerospace and automotive) and tourism. Lockdowns became necessary as a preventive measure to avoid the spread of the contagious and infectious “Coronavirus Disease 2019” (COVID-19). This newly identified disease is caused by a new strain of the virus being referred to as Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS CoV-2; formerly called 2019-nCoV). We review the current medical and manufacturing response to COVID-19, including advances in instrumentation, sensing, use of lasers, fumigation chambers and development of novel tools such as lab-on-the-chip using combinatorial additive and subtractive manufacturing techniques and use of molecular modelling and molecular docking in drug and vaccine discovery. We also offer perspectives on future considerations on climate change, outsourced versus indigenous manufacturing, automation, and antimicrobial resistance. Overall, this paper attempts to identify key areas where manufacturing can be employed to address societal challenges such as COVID-19. 相似文献
997.
Bergenia (Saxifragaceae) genus is native to central Asia and encompasses 32 known species. Among these, nine are of pharmacological relevance. In the Indian system of traditional medicine (Ayurveda), “Pashanabheda” (stone breaker) is an elite drug formulation obtained from the rhizomes of B. ligulata. Bergenia species also possess several other biological activities like diuretic, antidiabetic, antitussive, insecticidal, anti-inflammatory, antipyretic, anti-bradykinin, antiviral, antibacterial, antimalarial, hepatoprotective, antiulcer, anticancer, antioxidant, antiobesity, and adaptogenic. This review provides explicit information on the traditional uses, phytochemistry, and pharmacological significance of the genus Bergenia. The extant literature concerned was systematically collected from various databases, weblinks, blogs, books, and theses to select 174 references for detailed analysis. To date, 152 chemical constituents have been identified and characterized from the genus Bergenia that belong to the chemical classes of polyphenols, phenolic-glycosides, lactones, quinones, sterols, tannins, terpenes, and others. B. crassifolia alone possesses 104 bioactive compounds. Meticulous pharmacological and phytochemical studies on Bergenia species and its conservation could yield more reliable compounds and products of pharmacological significance for better healthcare. 相似文献
998.
Udhaya Kumar S. Srivarshini Sankar Salma Younes Thirumal Kumar D. Muneera Naseer Ahmad Sarah Samer Okashah Balu Kamaraj Abeer Mohammed Al-Subaie George Priya Doss C. Hatem Zayed 《Molecules (Basel, Switzerland)》2020,25(23)
Filamins (FLN) are a family of actin-binding proteins involved in regulating the cytoskeleton and signaling phenomenon by developing a network with F-actin and FLN-binding partners. The FLN family comprises three conserved isoforms in mammals: FLNA, FLNB, and FLNC. FLNB is a multidomain monomer protein with domains containing an actin-binding N-terminal domain (ABD 1–242), encompassing two calponin-homology domains (assigned CH1 and CH2). Primary variants in FLNB mostly occur in the domain (CH2) and surrounding the hinge-1 region. The four autosomal dominant disorders that are associated with FLNB variants are Larsen syndrome, atelosteogenesis type I (AOI), atelosteogenesis type III (AOIII), and boomerang dysplasia (BD). Despite the intense clustering of FLNB variants contributing to the LS-AO-BD disorders, the genotype-phenotype correlation is still enigmatic. In silico prediction tools and molecular dynamics simulation (MDS) approaches have offered the potential for variant classification and pathogenicity predictions. We retrieved 285 FLNB missense variants from the UniProt, ClinVar, and HGMD databases in the current study. Of these, five and 39 variants were located in the CH1 and CH2 domains, respectively. These variants were subjected to various pathogenicity and stability prediction tools, evolutionary and conservation analyses, and biophysical and physicochemical properties analyses. Molecular dynamics simulation (MDS) was performed on the three candidate variants in the CH2 domain (W148R, F161C, and L171R) that were predicted to be the most pathogenic. The MDS analysis results showed that these three variants are highly compact compared to the native protein, suggesting that they could affect the protein on the structural and functional levels. The computational approach demonstrates the differences between the FLNB mutants and the wild type in a structural and functional context. Our findings expand our knowledge on the genotype-phenotype correlation in FLNB-related LS-AO-BD disorders on the molecular level, which may pave the way for optimizing drug therapy by integrating precision medicine. 相似文献
999.
Soumen Dutta Nitee Kumari Sateesh Dubbu Sun Woo Jang Amit Kumar Hiroyoshi Ohtsu Junghoon Kim Seung Hwan Cho Masaki Kawano In Su Lee 《Angewandte Chemie (International ed. in English)》2020,59(9):3416-3422
Rational engineering and assimilation of diverse chemo‐ and biocatalytic functionalities in a single nanostructure is highly desired for efficient multistep chemical reactions but has so far remained elusive. Here, we design and synthesize multimodal catalytic nanoreactors (MCNRs) based on a mesoporous metal‐organic framework (MOF). The MCNRs consist of customizable metal nanocrystals and stably anchored enzymes in the mesopores, as well as coordinatively unsaturated cationic metal MOF nodes, all within a single nanoreactor space. The highly intimate and diverse catalytic mesoporous microenvironments and facile accessibility to the active site in the MCNR enables the cooperative and synergistic participation from different chemo‐ and biocatalytic components. This was shown by one‐pot multistep cascade reactions involving a heterogeneous catalytic nitroaldol reaction followed by a [Pd/lipase]‐catalyzed chemoenzymatic dynamic kinetic resolution to yield optically pure (>99 % ee) nitroalcohol derivatives in quantitative yields. 相似文献
1000.
Amit Mondal Biswajit Bhattacharya Susobhan Das Surojit Bhunia Rituparno Chowdhury Somnath Dey C. Malla Reddy 《Angewandte Chemie (International ed. in English)》2020,59(27):10971-10980
Ductility is a common phenomenon in many metals but is difficult to achieve in molecular crystals. Organic crystals bend plastically on one or two face‐specific directions but fracture when stressed in any other arbitrary directions. An exceptional metal‐like ductility and malleability in the isomorphous crystals of two globular molecules, BH3NMe3 and BF3NMe3, is reported, with characteristic tensile stretching, compression, twisting, and thinning. The mechanically deformed samples, which transition to lower symmetry phases, retain good long‐range order amenable to structure determination by single‐crystal X‐ray diffraction. Molecules in these high‐symmetry crystals interact through electrostatic forces (B??N+) to form columnar structures with multiple slip planes and weak dispersive forces between columns. On the other hand, the limited number of facile slip planes and strong dihydrogen bonding in BH3NHMe2 negates ductility. Our study has implications for the design of soft ferroelectrics, solid electrolytes, barocalorics, and soft robotics. 相似文献