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The current work aimed to fabricate a new cocaine sensor of octahedral palladium‐doped cobaltite composite (Oh‐Pd2+ : Co3O4‐C) using a simple hydrothermal protocol. As‐fabricated cocaine sensing approach was validated by various methods. Energy dispersive X‐ray analysis, X‐ray diffraction and scanning electron microscopy were recruited to characterize our charged modified composite. The electrode could sensitively detect cocaine, with a lengthy linear range (0.01 μM–900.0 μM) and a limit of detection (1.3 nM). The quantitative cocaine determination was achieved in the biological specimens using our modified electrode, the results of which displayed admirable outcomes. [ABSTRACT FROM AUTHOR]

Three new water soluble ternary metal complexes, [Co(metf)(en)2]Cl2(1), [Ni(metf)(en)2]Cl2(2), and [Cu(metf)(en)2]Cl2(3), (Metf = metformin, en = ethylenediamine), were synthesized and characterized, and pharmacodynamic evaluation was reported. From the spectral analysis, octahedral geometry was proposed to all the three metal complexes. The Kinetic parameters have been determined by thermogravimetric data using Coats‐Redfern method. The stability of the complexes was obtained from their molecular orbital structures from which the quantum chemical parameters were calculated using the highest occupied molecular orbital (HOMO)‐lowest unoccupied molecular orbital (LUMO) energies. The DNA binding studies of these complexes were explored by absorption, emission, and viscosity. Groove mode of surface binding of these complexes with DNA was explained by viscosity studies. Nuclease activity exhibited by these complexes on pUC19 DNA was experimented by agarose gel electrophoresis. Discovery Studio 2.1 software was used for docking studies of these complexes into B‐DNA sequence, 5′(D*AP*CP*CP*GP*AP*CP*GP*TP*CP*GP*GP*T)‐3′ retrieved from protein data bank (PDB ID: 423D). The maximum score is seen for complex 1. The antihyperglycemic activity of these complexes was studied in streptozotocin (STZ)‐diabetic rats. The substantial increase in the antihyperglycemic activity of the complexes is seen when compared with pure drug. The maximum antihyperglycemic activity is recorded for complex 1. [ABSTRACT FROM AUTHOR]

Chemists of the late 19th century, including Alfred Werner, prepared salts containing either green or violet cations of composition [CoCl2(en)2]+ (en is ethylenediamine, C2H8N2); we now refer to these as trans‐dichloro and cis‐dichloro species. We have discovered a third salt, purple in color, containing cations of the same elemental composition and whose asymmetric unit composition is [CoCl2(en)2]2Cl2·3H2O, in which the cobalt cations are a cis:trans dichloro pair. Such a discovery would undermine Werner's argument that if only two forms can be prepared, his octahedral theory was proven. Probably because his students never examined their crystals under a microscope, they failed to observe the 'third' species, thereby ruining Werner's argument since he relied strictly on color to identify them. That was fortunate since our purple salt would have led him to abandon, or certainly delay, his momentous discovery. Our crystals consist of a 1:1 mixture of the cis and trans cations, thereby sharing the same elemental analysis and conductivity as the single salts, but not their crystal structure, inasmuch as X‐ray diffraction had not even been discovered then. Serendipitously, our discovery would have been a great boon to his theoretical acumen, while his 'two‐color' argument may have doomed him. [ABSTRACT FROM AUTHOR]

Several decades after the bis(diethyl etherate) of tungsten(IV) chloride was first mentioned in the literature, it has now at last been structurally characterized by single‐crystal X‐ray diffraction analysis, finally confirming its composition. [ABSTRACT FROM AUTHOR]

The sodium complex [{Ph2P(O)NH(2,6-Me2C6H3)}Na{Ph2P(O)N(2,6-Me2C6H3)}]2 ( 2) with the ligand N-(2,6-dimethylphenyl)diphenylphosphinic amide was synthesized involving the reaction of the neutral ligand [Ph2P(O)NH(2,6-Me2C6H3)] ( 1) and sodium bis(trimethylsilyl)amide in toluene at 60 °C. The calcium complex [{Ph2P(O)NH(2,6-Me2C6H3)CaI(THF)3}I] ( 3) was obtained by the reaction between the neutral ligand 1 and anhydrous calcium diiodide in THF at ambient temperature. The solid-state structures of the complexes were established by single-crystal X-ray diffraction analysis. In the solid-state structure of 2, the sodium ion is coordinated through the chelation of oxygen atom attached to the phosphorus atom. Two different P-N and P-O bond lengths are observed, which indicates that one ligand moiety is anionic, whereas the second one is neutral. In the solid-state structure of 3, the calcium atom adopts distorted octahedral arrangement through the ligation of two phosphinic amide ligands, three THF molecules, and one iodide ion. [ABSTRACT FROM AUTHOR]

New cobalt(II) and nickel(II) complexes of 12-membered macrocyclic Schiff - base ligand containing thiosemicarbazone moiety as a part of ring have been prepared having general composition [MLX2] where M = Co(II) or Ni(II), L=3,4,9,10-tetra-2-furanyl-1,2,5,6,8,11- hexaazacyclododeca-7,12- dithione - 2,4,8,10 - tetraene, X = Cl-, NO3 -, NCS- . The complexes have been characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, spectral (IR, electronic, EPR) techniques and thermal analysis. Spectroscopic studies suggested a six coordinated octahedral geometry for all the complexes. The IR spectra of complexes suggest that ligand is coordinated to the metal ion through its four imines nitrogen. Conductivity measurements supported the non electrolytic nature of the complexes. The antifungal activities of complexes have been studied against a number of pathogenic fungi under laboratory conditions. The complexes showed good antifungal results. Thermal analysis of reported complexes suggests the absence of water molecule either in or outside the coordination sphere. [ABSTRACT FROM AUTHOR]

The report of the crystal structure of a new form of [CoCl2(en)2]Cl is both interesting and important as it allows a reassessment of the early work of Werner and brings an emphasis to the occurrence of cocrystals of complexes. [ABSTRACT FROM AUTHOR]

This work introduces a calibrated B3LYP/6-31G(d) study on the electronic structure of singlet and triplet neutral species of 1,2-substituted icosahedral 1,2-R2-1,2-C2B10H10 and octahedral 1,2-R2-1,2-C2B4H4 molecules with R = {H, OH, SH, NH2, PH2, CH3, SiH3} and their respective dianions formed by proton removal on each R group. A variety of small adiabatic singlet-triplet gaps ΔEST are obtained from these systems ranging from 2.93 eV (R = NH2) ≤ ΔEST ≤ 3.98 eV (R = SiH3) for the icosahedral neutrals and 1.56 eV (R = NH2) ≤ ΔEST ≤ 4.13 eV (R = SiH3) for the octahedral neutrals, these gaps being globally smaller for the dianionic systems, ranging from 0.94 eV (R- = CH2-) ≤ ΔEST ≤ 2.01 (R- = e-) for the icosahedral dianions 1,2-(R-)2-C2B10H10 and 0.91 (R- = CH2-) ≤ ΔEST ≤ 2.41 (R = SiH2-) for the octahedral dianions 1,2-(R-)2&bond;C2B4H4 (R- = e-, O-, S-, NH-, PH-, CH2-, PH2-). The different gaps lie within or in the neighborhood of the visible region of the electromagetic spectrum. The optimized geometries for the molecular cage remain similar in substituted icosahedral and octahedral singlet states, while a rich variety of different structures can be found for the optimized triplet states. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 524–535, 2006 [ABSTRACT FROM AUTHOR]