No abstract

2-(1H-Tetrazol-5-yl)pyridine (L) has been reacted separately with Me2NCH2CH2Cl⋅HCl and ClCH2CH2OH to yield two regioisomers in each case, N,N-dimethyl-2-[5-(pyridin-2-yl)-1H-tetrazol-1-yl]ethanamine (L1)/N,N-dimethyl-2-[5-(pyridin-2-yl)-2H-tetrazol-2-yl]ethanamine (L2) and 2-[5-(pyridin-2-yl)-1H-tetrazol-1-yl]ethanol (L3)/2-[5-(pyridin-2-yl)-2H-tetrazol-2-yl]ethanol (L4), respectively. These ligands, L1-L4, have been coordinated with CuCl2 ⋅H2O in 1 : 1 composition to furnish the corresponding complexes 1-4. EPR Spectra of Cu complexes 1 and 3 were characteristic of square planar geometry, with nuclear hyperfine spin 3/2. Single X-ray crystallographic studies of 3 revealed that the Cu center has a square planar structure. DNA binding studies were carried out by UV/VIS absorption; viscosity and thermal denaturation studies revealed that each of these complexes are avid binders of calf thymus DNA. Investigation of nucleolytic cleavage activities of the complexes was carried out on double-stranded pBR322 circular plasmid DNA by using a gel electrophoresis experiment under various conditions, where cleavage of DNA takes place by oxidative free-radical mechanism (OH(⋅)). In vitro anticancer activities of the complexes against MCF-7 (human breast adenocarcinoma) cells revealed that the complexes inhibit the growth of cancer cells. The IC50 values of the complexes showed that Cu complexes exhibit comparable cytotoxic activities compared to the standard drug cisplatin.

No abstract

Na-ion conducting Na 1+x [Sn x Ge 2Àx (PO 4 ) 3 ] (x = 0, 0.25, 0.5, and 0.75 mol%) glass samples with NASICON-type phase were synthesized by the melt quenching method and glass-ceramics were formed by heat treating the precursor glasses at their crystallization temperatures. XRD traces exhibit formation of most stable crystalline phase NaGe 2 (PO 4 ) 3 (ICSD-164019) with trigonal structure. Structural illustration of sodium germanium phosphate [NaGe 2 (PO 4 ) 3 ] displays that each germanium is surrounded by 6 oxygen atom showing octahedral symmetry (GeO 6 ) and phosphorous with 4 oxygen atoms showing tetrahedral symmetry (PO 4 ). The highest bulk Na + ion conductivities and lowest activation energy for conduction were achieved to be 8.39 9 10 À05 S/cm and 0.52 eV for the optimum substitution levels (x = 0.5 mol%, Na on Na-Ge-P network. CV studies of the best conducting Na 1.5 [Sn 0.5 Ge 1.5 (PO 4 ) 3 ]glass-ceramic electrolyte possesses a wide electrochemical window of 6 V. The structural and EIS studies of these glass-ceramic electrolyte samples were monitored in light of the substitution of Ge by its larger homologue Sn.conductivity, electrical properties, glass-ceramics, microstructure | INTRODUCTIONInvestigations on Na-ion battery technology have attracted significantly in the last few years as emerging storage technology for stationary applications such as grid-scale, mini grid energy storage devices, and also for renewable energy integration such as solar and wind power where gravimetric energy can be compromised. 1,2 Solid-state electrolytes having high Na + ion conductivity are of interest for safest energy storage, lowest cost, long cycle life, and high rate capabilities which are critical to develop room-temperature rechargeable sodium batteries. 3 Systematic studies on electrolyte materials relatively limited in order to realize safer sodium ion batteries with improved performance that operate under ambient conditions in view of the fact that there is hardly accepted negative electrode. Hence, the current challenge is to investigate, characterize, and optimize suitable solid-state electrolyte materials with higher Na + ion conductivity, and engineer the desired properties to provide stable interfacial contact. Alkali oxide (Li/Na) glass and glass-ceramic electrolytes are being widely used in storage and sensing devices because of their better conducting and physicochemical properties than their crystalline counter parts and further modified as a function of composition and controlled crystallization. [4][5][6] Hayashi et al. have been reported on chemical, mechanical, and ionic conductivity studies to closely meet desired current densities of various glass and glass-ceramic electrolytes mixed with various modifiers.7-9 Among several oxide glass electrolytes for sodium ion secondary batteries, sodium-

3 OH].CH 3 OH] (3). Crystal structures of complexes 1-3 were determined by single-crystal X-ray diffraction studies. The single-crystal X-ray diffraction analysis confirmed that complex 1 is an one-dimensional polymeric chain in which Cd(II) ions are bridged by one thiocyanate group bonding in an end-to-end fashion. Complex 2 is a centrosymmetric octanuclear complex with double endon azide (m 1,1 -N 3 À ) as linker. On the other hand, 3 is a dinuclear complex with terminally bound Cl À ions. Analysis of the structure revealed that all the complexes possess a 4membered Cd 2 (m 2 -O) 2 core fastened by the combined coordination action of a doubly deprotonated ligand. Complexes 1-3 have been successfully characterized by elemental analyses, IR and UV-Vis spectroscopy. The luminescent properties of complexes 1-3 have been studied in DMSO solution. The antibacterial and antibiofilm potential for complexes 1-3 were investigated against Gram-positive and Gram-negative bacterial strains. Intermolecular interactions with respect to percentages of hydrogen bonding of cadmium complexes were quantified by Hirshfeld surface.[a] Prof.