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Although generation of reactive oxygen species (ROS) by anthracycline anticancer drugs is essential for anti-tumor activity, they make these drugs cardiotoxic.

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The chemical and electrochemical reduction of CO2 to value added chemicals entails the development of efficient and selective catalysts. Synthesis, characterization and electrochemical CO2 reduction activity of a air-stable cobalt­(III) diphenylphos­phenethano-bis­(2-pyridinethiolate)­chloride [{Co­(dppe)­(2-PyS)2}­Cl, 1-Cl] complex is divulged. The complex reduces CO2 under homogeneous electrocatalytic conditions to produce CO with high Faradaic efficiency (FE > 92%) and selectivity in the presence of water. Through detailed electrochemical investigations, product analysis, and mechanistic investigations supported by theoretical calculations, it is established that complex 1-Cl reduces CO2 in its Co­(I) state. A reductive cleavage leads to a dangling protonated pyridine arm which enables facile CO2 binding through a H-bond donation and facilitates the C–O bond cleavage via a directed protonation. A systematic benchmarking of this catalyst indicates that it has a modest overpotential (∼180 mV) and a TOF of ∼20 s–1 for selective reduction of CO2 to CO with H2O as a proton source.

Metal–organic polyhedra (MOP) are a promising class of crystalline porous materials with multifarious potential applications. Although MOPs and metal–organic frameworks (MOFs) have similar potential in terms of their intrinsic porosities and physicochemical properties, the exploitation of carboxylate MOPs is still rudimentary because of the lack of systematic development addressing their chemical stability. Herein we describe the fabrication of chemically robust carboxylate MOPs via outer‐surface functionalization as an a priori methodology, to stabilize those MOPs system where metal–ligand bond is not so strong. Fine‐tuning of hydrophobic shielding is key to attaining chemical inertness with retention of the framework integrity over a wide range of pH values, in strong acidic conditions, and in oxidizing and reducing media. These results are further corroborated by molecular modelling studies. Owing to the unprecedented transition from instability to a chemically ultra‐stable regime using a rapid ambient‐temperature gram‐scale synthesis (within seconds), a prototype strategy towards chemically stable MOPs is reported.

Assimilation of open metal sites (OMSs) and free functional organic sites (FOSs) with a framework strut has opened up a new route for the fabrication of novel metal-organic materials, thereby providing a unique opportunity to explore their multiple functionalities. A new metal-organic framework (MOF), {[Cu(ina)2(H2O)][Cu(ina)2(bipy)]·2H2O}n (1) (ina=isonicotinate, bipy=4,4'-bipyridine), has been synthesized and characterized. Complex 1 is crystallized in the orthorhombic noncentrosymmetric space group Aba2 and consists of two different 2D coordination polymers, [Cu(ina)2(H2O)]n and [Cu(ina)2(bipy)]n, with entrapped solvent water molecules. Hydrogen-bonding interactions assemble these two different 2D coordination layers in a single-crystal structure with interdigitation of pendant 4,4'-bipy from one layer into the groove of another. Upon removal of guest molecules, 1 undergoes a structural transformation in single-crystal-to-single-crystal fashion with expansion of the effective void space. Each metal center is five-coordinated and thus can potentially behave as an OMS, and the free pyridyl groups of pendant 4,4'-bipy moieties and free -C=O groups can act as free FOSs. Thus, owing to presence of both OMSs and free FOSs, the framework exhibits multifunctional properties. Owing to the presence of OMSs, the framework can act as a Lewis acid catalyst as well as a small-molecule sensor material, and in a similar way, owing to the presence of free FOSs, it performs as a Lewis base catalyst and a cation sensor material. Furthermore, owing to noncentrosymmetry with large polarity along a particular direction, it shows strong second-harmonic generation/nonlinear optical (SHG-NLO) activity.

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The present study reports the antibacterial properties of flower-shaped ZnO (FZnO) microstructures and its comparison with that of hexagon-shaped bulk ZnO (BZnO) nanostructures. The samples are prepared successfully by wet chemical method and the surface morphologies, structures and size of the ZnO samples are characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), BET adsorption isotherm, and Photoluminescence (PL) Spectroscopy. The SEM and TEM images of the sample have confirmed flower-shaped structure of the ZnO. The materials are also analyzed by using an innovative tool called Lacunarity, a nonlinear dynamical (NLD) tool for proper understanding of the inherent surface properties of the particles formed, comparing the results estimated with the BET results obtained, thereby confirming our proposition to use it as an important parameter in predictive models. In this new approach, geometry of the surface structure is being associated with biological properties, in order to come up with easier ways to identify materials for any such applications where rich surface structure is desired. The photocatalytic activity of the flower-shaped material is carried out to find out its optical properties as another marker for confirming the antimicrobial activities. It has been reported for the first time that the prominent antibacterial activities are favoured by the FZnO microstructure having lesser Lacunarity, significantly better than its bulk counterpart, for inhibiting gram negative-Escherichia coli microorganism. Nanotechnology, at present, pertains to creation of useful materials, devices, and systems through appropriate manipulation of matter. A significant number of researchers have reported that formation of ZnO nanostructures in different shapes, such as, nanorod, nanoplates, nanowire 1 , flower-shaped ZnO microstructures 2 , etc. In the present work, two important attributes, capping and molarity, are used to control the particle size and their agglomeration 3. It is reported in W Yu et al. (2016), that photo-generated electrons in ZnO are much lighter than their corresponding holes, which indicates that it belongs to the n-type semiconductor 4. This result paves the way for obtaining excitation energy of electrons in ZnO that determines its optical property. ZnO materials are good inhibitors of microorganisms, and it is believed that this activity is enhanced in case of ZnO due to its high surface morphology. The capped ZnO usually shows up higher antibacterial activity than the uncapped one 5. In the present work, flower-shaped ZnO (FZnO) microstructures in PVP matrix and uncapped hexagon-shaped bulk ZnO (BZnO) nanostructures are synthesized for the study of their antimicrobial properties. The as-prepared samples are characterized by X-ray diffraction (XRD) 6 , Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) to find their size and shape 7,8. Further, the FZnO are characterized by UV-spectra, Photoluminescence (PL) Spec...