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Background: Mechanical revascularization of the infarct-related artery (IRA) is the most effective treatment modality in ST-segment elevation myocardial infarction (STEMI).No flow occurs in ∼8.8-10% of cases of primary percutaneous coronary intervention(PCI) in STEMI patients. Our aim was to study actual incidence and outcome of no flow patients. Methods: Five hundred and eighty primary PCI patients were studied over a period of two years i.e. January 2016 to December 2017. Drug eluting stents were used in all cases. Majority of our patients(>90%) came 6 hours after onset of chest pain. There were many patients where there was no flow even after mechanical thrombus aspiration and pharmacological vasodilator therapy. We have studied primary outcome(mortality) of no flow in those patients. Results: There were 44 cases of no flow in our series(7.75%). Left anterior descending artery(LAD )was involved in eighteen patients. Right coronary artery(RCA) was culprit in twenty four cases. Only two cases were seen in LCX territory. One month mortality rate in no flow group was 50% and 6.25% in successful recanalization group. One year mortality was 12.5% in successful recanalization group and 66% in no flow group. Conclusion: Refractory no flow during primary PCI in STEMI is associated with high mortality and morbidity. There is no established strategy to solve this phenomenon.

Data association is an integral process in tracking multiple targets with multiple sensors in a cluttered environment. With the help of data association, we obtain the relationship between sensor measurements and existing tracks. Tracking moving targets from a stationary position is likely a potential problem for losing tracks or track mingling. To overcome this problem, we employ a clustering algorithm solution developed using the nearest neighbour technique with the help of an Extended Kalman Filter. This paper focuses on finding out the real-time clustering solution for each target, having at most one measurement from any heterogeneous sensors at a particular timestamp. Here we employ a novel multi-target tracking algorithm using three basic association techniques, i.e. track-to-track association, measurement-to-measurement association and track-to-measurement association. Our real-time data simulation experiments show that the data association algorithm implemented works effectively and gives a good efficiency in real-time multi-target multi-sensor environ-ments.

Chagas disease is caused by the protozoan parasite

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi. It is endemic in South and Central America and recently has been found in other parts of the world, due to migration of chronically infected patients. The current treatment for Chagas disease is not satisfactory, and there is a need for new treatments. In this work, we describe the optimization of a hit compound resulting from the phenotypic screen of a library of compounds against T. cruzi. The compound series was optimized to the level where it had satisfactory pharmacokinetics to allow an efficacy study in a mouse model of Chagas disease. We were able to demonstrate efficacy in this model, although further work is required to improve the potency and selectivity of this series.

A new ion-exchanger having chemical formula [Me2NH2]3[Mo12O40S] and belonging to the class of Keggin type polyoxometalate was synthesized and characterized by single-crystal X-ray structure determination. The crystal of the exchanger is rhombohedral, space group R-3 with cell dimensions, a =16.504(18) A, b =16.504(18)A (1) A, c =25.23(3)A and α=90.00°, β=90.00°, γ=120.00° and Z =6, 3.284gcm-3. The compound behaves as an ion-exchanger and it is significantly stable towards thermal, chemical environments and total radiation dose of 35.0kGy. Radiochemical separation of the short-lived daughter carrier-free 9°Y (T1/2 =64.08h) from its long-lived parent 90Sr (T1/2 =29 a) using this material at pH 6.0 with 1.0% EDTA solution as an eluent.

Additional file 3. Scheme depicting the role of dUTPase in pyrimidine metabolism. UMP/CMPK (putative), uridine monophosphate/cytidine monophosphate kinase; NDK, nucleoside-diphosphate kinase; CTPS, cytidine triphosphate synthetase; RNR, ribonucleotide reductase; dUTPase, deoxyuridine 5’-triphosphate nucleotido-hydrolase; DHFR-TS, dihydrofolate reductase / thymidylate synthase; TMPK, thymidine monophosphate kinase.

[Background] Malaria remains as a major global problem, being one of the infectious diseases that engender highest mortality across the world. Due to the appearance of resistance and the lack of an effective vaccine, the search of novel anti-malarials is required. Deoxyuridine 5′-triphosphate nucleotido-hydrolase (dUTPase) is responsible for the hydrolysis of dUTP to dUMP within the parasite and has been proposed as an essential step in pyrimidine metabolism by providing dUMP for thymidylate biosynthesis. In this work, efforts to validate dUTPase as a drug target in Plasmodium falciparum are reported., [Methods] To investigate the role of PfdUTPase in cell survival different strategies to generate knockout mutants were used. For validation of PfdUTPase as the intracellular target of four inhibitors of the enzyme, mutants overexpressing PfdUTPase and HsdUTPase were created and the IC50 for each cell line with each compound was determined. The effect of these compounds on dUTP and dTTP levels from P. falciparum was measured using a DNA polymerase assay. Detailed localization studies by indirect immunofluorescence microscopy and live cell imaging were also performed using a cell line overexpressing a Pfdut-GFP fusion protein., [Results] Different attempts of disruption of the dut gene of P. falciparum were unsuccessful while a 3′ replacement construct could recombine correctly in the locus suggesting that the enzyme is essential. The four 5′-tritylated deoxyuridine analogues described are potent inhibitors of the P. falciparum dUTPase and exhibit antiplasmodial activity. Overexpression of the Plasmodium and human enzymes conferred resistance against selective compounds, providing chemical validation of the target and confirming that indeed dUTPase inhibition is involved in anti-malarial activity. In addition, incubation with these inhibitors was associated with a depletion of the dTTP pool corroborating the central role of dUTPase in dTTP synthesis. PfdUTPase is mainly localized in the cytosol., [Conclusion] These results strongly confirm the pivotal and essential role of dUTPase in pyrimidine biosynthesis of P. falciparum intraerythrocytic stages., This work was funded by the Junta de Andalucía (BIO-199); the Plan Nacional de Investigación Científica, Instituto de Salud Carlos III-Subdirección General de Redes y Centros de Investigación Cooperativa-Red de Investigación Cooperativa en Enfermedades Tropicales (RICET: RD16/0027/0014); The European Union (contract 037587); and the Plan Nacional (SAF2016-79957-R).

Audio mining, also called audio searching, takes a spoken query and locates the search term in an audio/speech file. Spoken query search or spoken term detection (STD) provides an efficient means for content-based retrieval of speech files. To perform STD, the posterior features of the spoken query as well as the audio files are well utilized. The posterior features are computed by training the Gaussian mixture model (GMM) with mel-frequency cepstral coefficients (MFCC) of audio files. A distance matrix is computed between each pair of query with audio files posterior features to examine the matched portions. To identify and extract the matched portions from the distance matrix an novel pattern identification method is proposed using image processing techniques and dynamic time warping (DTW). By processing the spoken query with our proposed method, most of the matched audio files containing the spoken query are retrieved. The performance of the proposed method is evaluated using the standard metric like average precision (AP). For experimentation of the proposed method Hindi news speech data was used.

Background: Peptic ulcer disease is a result of an imbalance between aggressive and defensive factors. Morin, a bioflavonoid exhibits many biological activities such as antioxidant and anti-inflammatory properties. Objective: The present study was conducted to unravel the therapeutic potential of morin in acetic acid-induced gastric ulcer. Materials and Methods: Gastric ulcer was induced in male Wistar rats (180-220 g) by applying glacial acetic acid (10 M, 100 μL) to serosa of the stomach. Morin (10, 30 and 100 mg kgG 1 , p.o.) was administered for 15 days after the induction of ulcer. After end of treatment gastric specimens were collected for biochemical and histological evaluation. Results: There was a significant (p

On reaction of 1,2-bis(2-pyridylmethylthio)-bis-ethylsulphide (L) with copper(II) chloride in presence of an excess of azide ions led to the formation of a new copper(II) complex formulated as [Cu(2-PTrz) 2 (H 2 O) 2 ] ( 1 ), where 2-PTrz = 5-(2-pyridyl)-1,3,4-triazole is formed through the cleavage of C–S bond in L promoted by copper(II) chloride. The precursor of 1 is the in situ formed Cu(pic) 2 derivative (pic = 2-picolinate), the existence of which has been established by separating out in pure form the complexes [Cu 2 (pic) 3 (H 2 O)](ClO 4 ) ( 2 ), [Cu 2 (pic) 3 (H 2 O](NO 3 ) ( 3 ) by using different anions. In addition [Cu(pyca)Cl] ( 4 ) (pyca = bis(pyridin-2-carbonyl)amine) was also obtained from 1 with a less quantity of azide. All the copper(II) complexes obtained in this study were characterized by physico-chemical tools as well as X-ray crystallographic studies. The 2-PTrz ligand separated out from 1 was used in the synthesis of the nickel(II) complex [Ni(2-PTrz) 2 (H 2 O) 2 ], 5 . The complexes 1 and 5 are isomorphous and isostructural. In dimethylformamide solution, complex 1 was found to exhibit Cu II /Cu I quasi-reversible redox couple in cyclic voltammograms with E 1/2 value of −340 mV (versus Ag/AgCl) at 298 K. The interaction of complex 1 with CT-DNA has been investigated spectroscopically. The results showed that the interaction mode between complex 1 and DNA might be groove binding.

The coordination behavior of pyridylmethylthioether type of organic moieties having N2S2 donor set [L 1 = 1,2-bis(2-pyridylmethylthio)ethane, L 2 = 1,3-bis(2-pyridylmethyl-thio)propane and L 3 = 1,4-bis(2-pyridylmethylthio)butane] with copper(II) chloride and copper(II) bromide have been studied in different chemical environments. Copper(II) chloride assisted C S bond cleavage of the organic moieties leading to the formation of copper(II) picolinate derivatives, whereas, under similar experimental conditions, no C S bond cleavage was observed in the reaction with copper(II) bromide. The resulted copper(II) complexes isolated from the different mediums have been characterized by spectroscopic and X-ray crystallographic tools.

Two new hexa-coordinated mononuclear copper(II) complexes of two ligands L-1 and L-2 containing NSSN donor sets formulated as [Cu(L)(H2O)(2)](NO3)(2) [1a, L = 1,2-bis(2-pyridylmethylthio)ethane (L-1), 1b L = 1,3-bis(2-pyridyl-methylthio)propane (L-2)] were synthesized and characterized by physico-chemical and spectroscopic methods. In 1a the single crystal X-ray crystallography analysis showed a distorted octahedral geometry about copper(II) ion. The crystal packing evidences pairs of complexes arranged about a center of symmetry and connected through a H-bond occurring between aquo ligands and nitrate anions. On reaction with chloride and pseudohalides (N-3(-) and SCN-), in acetonitrile at ambient temperature. complexes 1 changed to monocationic penta-coordinated mononuclear copper(H) species formulated as [Cu(L)(Cl)]NO3 (2), [Cu(L)(N-3)]NO3 (3). and [Cu(L)(SCN)]NO3 (4). These copper(II) complexes have been isolated in pure form from the reaction mixtures and characterized by physico-chemical and spectroscopic tools. The solid-state structure of 2a, established by X-ray crystallography, shows a trigonal bipyramidal geometry about the metal ion with a trigonality index (tau) of 0.561. (C) 2009 Elsevier B.V. All rights reserved.

One mononuclear copper(II) complex, containing neutral tetradentate NSSN-type ligands, of formulation [Cu II(L 1)Cl]ClO 4 (1), was synthesized and isolated in pure form [where L 1˭ 1,3-bis(3-pyridylmethylthio)propane]. Green-colored copper(II) complex was characterized by physicochemical, spectroscopic methods and conductivity measurement. These experimental data matched well with the proposed structure of the complex. Biological activity of the complex (1) toward calf thymus DNA and bovine serum albumin has been examined systematically and groove-binding behavior of the Copper(II) complex 1 with calf thymus DNA has been observed from the spectral study.

A new series of hexacoordinated octahedral nickel(II) complexes of 2-(pyridin-3-ylmethylsulfanyl)phenylamine (L) formulated as [Ni(L)4(X)2] (1–4) [where X = Cl− (1); NCO− (2); N3− (3) and NCS− (4)] has been synthesised and characterised by physicochemical, spectroscopic tools. Details of structural study of complex 1 using single crystal X-ray crystallography showed that distorted tetragonal environment around nickel(II) ion has been satisfied by four pyridinic-N donors of four organic moieties (L) and two chloride ions. All the complexes are redox active and the electrochemical study of the complexes showed only cathodic NiII/NiI redox couples in the range of −0.61 to −695 V versus Ag/AgCl. Interactions of 1 towards calf thymus-DNA by spectroscopic, viscosity-measurement and electrochemical study and towards bovine serum albumin (BSA) with the help of absorption and fluorescence spectroscopy were examined. Antibacterial activity of the complexes (1–4) studied by agar disc diffusion method showed the comparable inhibition activity of the nickel(II) complexes against some pathogenic bacteria namely Escherichia coli, Vibrio cholerae, Streptococcus pneumonia, Shigella sp. and Bacillus cereus.

Treatment of perchlorate or nitrate salt of cadmium(II) with carboxamide derivatives (L) generated four novel mononuclear metal complexes, represented as [Cd(L )4](ClO4)2 (1a and 1b) and [Cd(L)2(ONO2)2] (2a and 2b) in appreciable yields (L = L 1 = N-(furan-2-ylmethyl)-2-pyridine carboxamide and L = L 2 = N-(thiophen-2-ylmethyl)-2-pyridine carboxamide). The complexes have been characterized by FT-IR, UV-Visible, elemental analysis and single crystal X-ray crystallographic analysis which revealed eight coordinated cadmium ions, but in different coordination environments, depending on the counter anion used. In addition, electronic absorption, fluorescence spectroscopy and viscosity measurements revealed a significant interaction of the four complexes with CT-DNA via intercalative/groove binding mode. The intrinsic binding constant K b obtained varies from 0.4 × 10 4 to 1.11 × 10 5 M−1. The results suggest that neutral complexes 2a and 2b bind to DNA in an intercalative mode. On the other hand, cationic complexes 1a and 1b bind with DNA via weak electrostatic/covalent interaction.

A new ion-exchanger having chemical formula [Me

Hydrogen titanate nanotubes were synthesized by hydrothermal process using 10 M NaOH and TiO2 anatase powder. The material synthesized was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to ensure the structural and morphological characteristics. The interaction of calf thymus DNA (CT-DNA) and bovine serum albumin protein with suspended aqueous solution of titanate nanotubes was investigated using UV absorption spectroscopy and the apparent association constant was found to be, Kb= 1.68 × 104 M-1 and Kap=5.41 × 103 M-1 for DNA and BSA respectively. Addition of the titanate nano material resulted quenching of fluorescence spectra of ethidium bromide-DNA in tris HCl buffer solution and that of aqueous protein solution. The apparent binding constant (Ksv= 5.46 × 104M-1 for DNA binding and Ksv = 6.063 × 103M-1 for protein binding) was deduced from relevant fluorescence quenching data using Stern-Volmer equation.

A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography plates as a spray reagent. This new reagent enabled to produce various distinguishable colors with amino acids with different RF values. The detection limits and the binding ability of PDBIQ with amino acids have been calculated. PDBIQ is also able to detect aminoacids from hydrolised seed protein. The title compound also exhibited profound inhibitory action against some gm (+ve) and gm (-ve) bacterial organisms. This paper deals with synthesis, spectroscopic application and biological evaluation of the organic moity.

Zinc(II) complexes of the formula [Zn(L)(X) 2 ] (where X = Cl − , N 3 − , NCO − and SCN − ( 1a – d , respectively)) and {[Zn(L)(ClO 4 )(H 2 O)](ClO 4 )} n ( 2 ), were isolated in the pure form on the reaction of 1,3-bis(2-pyridylmethylthio)propane (L) with different zinc(II) salts. All the complexes were characterized by physicochemical and spectroscopic tools. The X-ray crystallographic analyses of the complexes 1d and 2 showed that the former is mononuclear while complex 2 is a 1D coordination polymer, {[Zn(L)(ClO 4 )(H 2 O)](ClO 4 )} n , due to a different coordination mode of the tetradentate ligand L. The zinc(II) ions present an octahedral coordination geometry in both compounds, which is more distorted in the mononuclear complex 1d . The study indicates that the counter anion of the zinc(II) salt used as reactant leads to a different type of complex when isolated as a crystalline material. A spectroscopic study of the interaction of complex, 2 with calf thymus-DNA (CT-DNA) in Tris–HCl buffer showed a significant non-intercalative interaction with a binding constant ( K b ) of 4.7 × 10 4 M −1 , and the linear Stern–Volmer quenching constant ( K sv ) and the binding sites ( n ) were found to be 1.3 × 10 3 and 0.92 respectively, calculated from ethidium bromide (EB) fluorescence displacement experiments.

A novel inorganic ion exchanger, aluminum tungstate, was prepared and characterized by spectroscopic tools and elemental analysis. The compound is resistant to heat and radiation and is stable in diverse chemical environments. This material exhibits an excellent adsorption of parent-daughter 137Cs-137m Ba. The newly prepared crystalline inorganic ion exchanger was employed for separation of the carrier-free 137m Ba from 137Cs using 0.0426 M ascorbic acid solution as eluting agent. Trend in elution is encouraging to apply the system as radionuclide generator.

A linear tri-nuclear oxamato bridged copper(II) complex [Cu3(pba)(dpa)2(H2O)(ClO4)](ClO4)·H2O (1) (pbaH4 = 1,3-propanediylbis(oxamic acid), dpa = 2,2′-dipyridylamine) was isolated from the reaction mixture of Na2[Cu(pba)]·3H2O, copper perchlorate hexahydrate and dipyridylamine in methanol. On reaction with dpa or DMF in basic medium (KOH) at ambient temperature complex 1 changed to dinuclear oxalate bridged copper(II) derivatives, [Cu2(μ-C2O4)(dpa)4](ClO4)2 (2) and [Cu2(μ-C2O4)(dpa)2(DMF)2](ClO4)2 (3), respectively. The complexes 1, 2 and 3 have been characterized by physicochemical and spectroscopic tools, and also by the X-ray single crystal analysis. The hydrolysis of 1 in basic medium and thermo-gravimetric analysis has been studied. Absorption and emission spectral studies showed that complex 1 interacts with calf thymus-DNA (CT-DNA) with a binding constant (Kb) of 4.01 × 104 M−1 and linear Stern–Volmer quenching constant (Ksv) of 6.9 × 104. A strong anti-ferromagnetic interaction with a coupling constant JCuCu of 320.0 ± 0.3 cm−1 was observed from the study of magnetic behavior of complex 1 in the temperature range of 2–300 K. Electrochemical equivalency of three copper(II) ions in 1 was identified by getting only one quasi reversible cyclic voltammogram.

The hexa-coordinated copper(II) complex [Cu(L)(DMF)2(ClO4)2], where L = 5-nitro-1,10-phenanthroline, was synthesized and characterized. The X-ray crystal structure shows that the copper is coordinated by the two N-atoms of the 1,10-phenanthroline ligand plus four O-atoms, two from DMF ligands and two from the perchlorate anions. Thermal analysis showed that the complex was stable up to 285 °C. The interaction of the complex with calf thymus DNA was investigated using absorption and emission spectroscopic studies, and the binding constant (K b) and linear Stern–Volmer quenching constant (K sv) have been determined. Electrochemical characterization of the complex in acetonitrile showed a quasi-reversible one-electron exchange voltammogram for the Cu2+/Cu+ redox couple at ca. E 1/2 = −1.00 V (versus SCE) with ΔE = 200 mV and i pc/i pa ≈ 1.

On reaction of 2-benzoylpyridine (Bzpy) with copper(II) ion, different types of copper(II) complexes have been isolated in pure form depending upon the counter anion of the copper(II) salts used as reactant and the pH of the medium. Mono-nuclear copper(II) complexes of formula [Cu(Bzpy)2(ClO4)2] (1) and [Cu(Bzpy)2(H2O)2](NO3)2 (2) were formed with copper(II) perchlorate and nitrate, respectively. On the other hand, following a similar reaction type in presence of alkali, we obtained the dinuclear copper(II) complex [Cu2(Bzpy)2{BzOpy}2(H2O)](ClO4)2 (3) containing the hydroxy-2-pyridylphenylmethanolato (BzOpy)− anion, achieved through the nucleophilic addition of the hydroxide to the carbonyl group of Bzpy, which is stabilized by metal complexation. However, this behavior was not recorded with copper(II) nitrate. The complexes were characterized by physicochemical and spectroscopic tools along with structural characterization by single crystal X-ray diffraction analysis. The interaction of dinuclear copper(II) complex 3 with calf thymus DNA (CT-DNA) has been investigated by using absorption and emission spectral studies and the binding constant (Kb) and the linear Stern–Volmer quenching constant (Ksv) have been determined. Complex 3 was active to oxidize the catechol to the corresponding quinone in MeCN medium via complex-catechol intermediate. Magnetic behavior for 3 is typical for uncorrelated spins down even up to 2 K.

Two series of zinc(II) complexes of two Schiff bases (H2L1 and H2L2) formulated as [Zn(HL1/HL2)]ClO4 (1a and 1b) and [Zn(L1/L2)] (2a and 2b), where H2L1 = 1,8-bis(salicylideneamino)-3,6-dithiaoctane and H2L2 = 1,9-bis(salicylideneamino)-3,7-dithianonane, have been prepared and isolated in pure form by changing the chemical environment. Elemental, spectral, and other physicochemical results characterize the complexes. A single crystal X-ray diffraction study confirms the structure of [Zn(HL1)]ClO4 (1a). In 1a, zinc(II) has a distorted octahedral environment with a ZnO2N2S2 chromophore.

Penta-coordinated mononuclear copper(II) complex of tridentate 2,6-bis-(benzimidazolyl)pyridine (L) formulated as [Cu(L)(H2O)2](NO3)2, 1 was synthesized and isolated in pure form. The complex was characterized by physico-chemical and spectroscopic methods, as well as single crystal X-ray diffraction analysis. The structural study shows the metal in a highly distorted square pyramidal geometry [trigonality index τ = 0.1425] that comprises two aqua molecules in the first coordination sphere. The crystal packing of 1 shows a 3D polymer formed through H-bonds involving aquo ligands, NH benzimidazole groups and nitrate anions. On reaction with pseudohalides in acetonitrile at ambient temperature complex 1 changed to mono cationic copper(II) derivatives [Cu(L)(X)(H2O)]NO3 [X = SCN− (2a) and N 3 - (2b)]. These copper(II) complexes have been isolated from the reaction mixtures and characterized by physico-chemical and spectroscopic tools. The interaction of complex 1 with calf thymus DNA (CT-DNA) has been investigated by using absorption and emission spectral studies, the binding constant (Kb) and the linear Stern–Volmer quenching constant (Ksv) have been determined.

A newly designed inorganic ion exchanger, based on aluminum vanadate, has been synthesized and characterized by elemental analysis, spectroscopic tools and powdered X-ray diffraction. The insoluble poorly polycrystalline material is highly stable towards thermal and radiation doses and in various chemical environments. The data of exchange capacities of the solid material for the different alkali and alkaline metal ions determined by batch technique show that the compound can be employed as an ion exchanger. The successful radiochemical separations of the no carrier added daughter nuclides; 137m Ba and 115m In from their respective parents present in equilibrium mixtures have been carried out using this material. Elutions of 137m Ba and 115m In were performed using 0.0426 mol L −1 ascorbic acid solution and 4.0 mol L −1 HCl, respectively, after sorption of the equilibrated mixtures 137 Cs– 137m Ba at 0.01 mol L −1 HCl medium and 115 Cd– 115m In at pH 7.0, respectively. In another column operation, it has been observed that the separation of gold and silver is possible with the help of the eluents, 0.01% alcoholic solution of Rhodamine-B for gold and 0.5% thiourea solution in 0.1 mol L −1 HClO 4 for silver, respectively, after the sorption of no carrier added onto this material at pH 2.0, at a no carrier added level.

A new inorganic ion exchanger, cerium(IV) iodotungstate, has been synthesized and characterized by elemental analysis and IR spectroscopy. This inorganic material is very stable thermally, chemically and with respect to radiation. Its ion exchange capacity for alkali and alkaline earth metal ions has been studied. 90 Y has been successfully separated from its parent 90 Sr in the equilibrium mixture with this exchanger at pH 6.0 with 0.0063 M EDTA solution as an eluent.

A new series of binary copper(II) complexes, [Cu(L)2] (2) [where L is a monobasic tridentate methylthioazophenolate having NSO donor sets], has been synthesized. The reddish brown colored complexes have been characterized by elemental analyses, spectroscopic and other physico-chemical tools. The detailed structure analysis of one of the complexes, [Cu(1a)2] (2a), by single-crystal X-ray crystallography shows that thioether-S donor center participates in coordination with the copper(II) ion with a weak interaction with long Cu–S(thioether) bond distances [2.956(2) A and 2.925(2) A]. Electrochemical study of the complexes in methanol using TBAP as supporting electrolyte shows that heterogeneous electron-transfer rate is low at the applied potential.

Two sets of nickel(II) complexes of a series of tetradentate NSNO ligands were synthesized and isolated in their pure form. All these complexes, formulated as $[Ni(L)Cl]_2$ and $[Ni(L)(N_3)]_2$ [HL = pyridylthioazophenols], were characterized using physicochemical and spectroscopic tools. The solid-state structures of two complexes (1a and 2a) were established by X-ray crystallography. The geometry about the nickel ion of the complexes is octahedral and the complexes are dimeric in nature. In 1, two Ni(II) ions are bridged by two $Cl^{-}$ anions while in 2 they are bridged by two azide ions in a \mu -1,1-bridging fashion.

Oxorhenium(V) complexes of β-diketonate systems have been synthesized and isolated in pure form. The red complexes n-Bu4N[ReO(R1COCHCOR2)Cl3] (acac, R1=R2=CH3; bzac, R1=CH3 and R2=C6H5; bzbz, R1=R2=C6H5) have been characterized by elemental analyses, spectroscopic and other physico-chemical tools. One complex, n-Bu4N[ReO(bzbz)Cl3] (1c) has been subjected to single-crystal X-ray analysis. In the structure of the anion, the metal has a six-coordinate octahedral environment in which the bidentate β-diketone ligand is cis and trans to the terminal oxygen.

Dry reaction of indoles and alkylindoles (1a–h) with triethyl orthoformate (2.5 equiv.) on acid‐washed montmorillonite K10 clay at room temperature afforded in

A series of anionic five-coordinate binary oxorhenium(V) complexes with dithiolato ligands, Bu4N[ReO(L1)2] (1a), Bu4N[ReO(L2)2] (1b), and Bu4N[ReO(L3)2] (1c), and a series of neutral octahedral ternary oxorhenium(V) complexes of mixed dithiolato and bipyridine ligands, [ReO(L1)(bpy)Cl] (2a), [ReO(L2)(bpy)Cl] (2b), and [ReO(L3)(bpy)Cl] (2c) (where L1H2 = ethane-1,2-dithiol, L2H2 = propane-1,3-dithiol, L3H2 = toluene-3,4-dithiol, and bpy = 2,2′-bipyridine), were isolated and characterized by physicochemical and spectroscopic methods. The solid state structure of 1c was established by X-ray crystallography. All the mononuclear oxorhenium(V) complexes are diamagnetic. The redox behavior of all the complexes has been studied voltammetrically.

Four indolic 1-azadienes (1a–c, 2) underwent Diels–Alder reaction, dienophile-catalysed addition–elimination reaction, Michael reaction or hydrolysis with three enoic, two ynoic and one azo dienophiles, leading to a γ-carboline, various 3-cyanoindoles, 3-formylindole and several nitrones.

C–S bond cleavage in pyridylmethylthioether systems promoted by oxorhenium(V) ion has been established performing the reaction of 1,2-bis(2-pyridylmethylthio)ethane(BPT1), 1,3-bis(2-pyridyl-methylthio)propane(BPT2) and 3,4-bis(2-pyridylmethylthio)-5-methyltoluene (BPT3) with Bu4N[ReOCl4] in dry alcoholoic medium. In case of BPT1 and BPT2, new 2-(2-pyridylmethylthio)ethane-1-thiol (L1H) and 3-(2-pyridylmethylthio)propane-1-thiol (L2H) ligand, respectively were formed in situ through cleavage of one C–S(thioether) bond, resulting in the neutral oxorhenium(V) complexes of formulation [ReO(L1)Cl2] (1a) and [ReO(L2)Cl2] (1b); where as in case of BPT3, binary oxorhenium(V) complex of 3,4-dimercapto-toluene ligand (L3H2), formulated as Bu4N[ReO(L3)2] (1c) through cleavage of two C–S(thioether) bonds. The presence of picolinic acid, as by-product in the filtrates of the C–S bond cleavage reactions in dry alcohol, was detected by treatment of copper(II) salts and GC–MS techniques. But in hydrated alcoholic medium no C–S bond cleavage induced by ReO(V) ion occurred in any of the BPT systems rather the conversion of ReO(V) into perrhenate salt was observed; this reaction mixture, in turn on reaction with copper(II) nitrate trihydrate salt, produce [Cu(BPT)Cl]ReO4 (2) type complexes. The solid-state structures of complexes 1a and 2a were established by X-ray crystallography.

Dry reaction of isatins (3a, 3b) with indoles (4a–e) on montmorillonite K10 clay at room temperature furnished within minutes 3,3-bis(3′-indolyl)-2-indolinones (1a–f) in high yields. 5-Nitroisatin (3c) furnished, in addition to the expected indolinone 1h, 3-hydroxy-3-(3′-indolyl)-5-nitro-2-indolinone (6), a likely intermediate to 1h.

Governments across the world are facing unique, deeper and unprecedented challenges. Interesting trends are observed in citizen service delivery as a response to these challenges. A solution architecture that may help the governments to address these trends is presented in this paper.