Solid state structure of the hydrated potassium thiocyanate complex of benzodinaphthopyridino 21-crown-7, C37H31NO6·KSCN·H2O (1 : 1 : 1)

Single crystal X-ray analysis of the hydrated KSCN complex of benzodinaphthopyridino-21-crown-7 (1) (1 : 1 : 1) is reported. Crystals of the complex are orthorhombic,Pnma, with = 16.946(4),b = 22.298(4),c = 10.390(8) Å andD _c = 1.184 g cm^–1,Z = 4. The host macroring (1) has a mirror symmetry and exists in a so-called dentists chair conformation. The cation (K^–) is coordinated to all the six ether oxygen atoms and also weakly to the pyridine N atom. The SCN^– anion group has a statistical type of disorder with opposite orientations of S and N such that nitrogen and sulphur are coordinated to K⁺. Packing of the host molecules is in columns to form quasi channels with K⁺, SCN^–, and H₂O being located inside the stacks. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82132 (9 pages).     

DNAzyme Based Amplified Biosensor on Ultrasensitive Fluorescence Detection of Pb (II) Ions from Aqueous System

A label -free DNAzyme amplified biosensor is found to be highly selective and sensitive towards fluorescent detection of Pb²⁺ ions in aqueous media. The DNAzyme complex has designed by the hybridization of the enzyme and substrate strand. In the presence of Pb²⁺, the DNAzyme activated and cleaved the substrate strand of RNA site (rA) into two oligonucleotide fragments. Further, the free fragment was hybridized with a complementary strand on the surface of MBs. After magnetic separation, SYBER Green I was added and readily intercalate with the dsDNA to gives a bright fluorescence signal with intensity directly proportional to the concentration of Pb²⁺ions. A detection limit of 5 nM in Pb²⁺ the detection range 0 to 500 nM was obtained. This label- free fluorescent biosensor has been successfully applied to the determination of environmental water samples. Then results open up the possibility for real-time quantitative detection of Pb²⁺ with convenient potential applications in the biological and environmental field.

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Synthesis, characterization and thermal expansion studies on europium titanate (Eu2TiO5)

The lattice thermal expansion characteristics of europium titanate (Eu₂TiO₅) have been studied by measuring the lattice parameter by high temperature X-ray diffraction technique (HT-XRD) in the temperature range 298–1573 K. Percentage linear thermal expansion and mean linear thermal expansion coefficients were computed from the lattice parameter data. The percentage linear thermal expansion in the temperature range 298–1573 K along a, b and c axes are 1.05, 1.15 and 0.95 respectively.     

Syntheses, X-ray structures and AACVD studies of group 11 ditelluroimidodiphosphinate complexes

Reactions of Na(tmeda)[N((i)Pr(2)PTe)(2)] with CuCl, AgI or AuCl (in the presence of PPh(3)) in THF produced the coinage metal ditelluroimidodiphosphinate complexes {Cu[N((i)Pr(2)PTe)(2)]}(3), (5), {Ag[N((i)Pr(2)PTe)(2)]}(6) (6) and Au(PPh(3))[N((i)Pr(2)PTe)(2)] (7), respectively. Complexes 5, 6 and 7 were characterized in the solid state by X-ray crystallography. Complex 5 is trimeric and exhibits a highly distorted Cu(3)Te(3) ring. In contrast, the Ag(I) complex 6 is a hexamer, and forms a twelve-membered Ag(6)Te(6) ring. The replacement of the (i)Pr groups on phosphorus by Ph results in an intriguing structural change to a tetramer with a boat-shaped Ag(4)Te(4) ring in {Ag[N(Ph(2)PTe)(2)}(4).2THF (8). The gold(I) complex 7 is monomeric. Aerosol-assisted chemical vapour deposition (AACVD) of compounds 5, 6 and 7 yields CuTe, Ag(7)Te(4), AuTe(2) and Au films, respectively. The films were grown at temperatures of 300-500 degrees C and characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive analysis of X-rays (EDAX).     

Induction of drought stress tolerance by ketoconazole in Catharanthus roseus is mediated by enhanced antioxidant potentials and secondary metabolite accumulation

A pot culture experiment was conducted to estimate the drought stress mitigating effect of ketoconazole (KCZ), a fungicide cum plant growth regulator, in Catharanthus roseus plants. The plants under pot culture were subjected to drought stress and drought stress with KCZ from 30 days after sowing (DAS) and regular irrigation was kept as control. Antioxidant contents and activities of antioxidant enzymes were estimated from root, stem and leaf of both control and treated plants. The alkaloid ajmalicine was extracted and estimated from the roots of control, drought stressed and KCZ treated plants. Individual and combined drought stress and KCZ treatments increased ascorbic acid, -tocopherol contents, superoxide dismutase, ascorbate peroxidase, catalase and polyphenol oxidase activities when compared to control. There was a significant enhancement in ajmalicine production under KCZ treated plants under drought stress when compared to well watered control as well as drought stressed plants. The KCZ treatment resulted in partial mitigation of drought stress by increasing the antioxidant potentials in C. roseus plants.     

Trans effect of triphenylphosphine on Ni–S bonds in solid state and DFT/B3LYP optimized structure: Synthesis,spectral and structural studies on (bis(2-ethylhexyl)dithiocarbamato-S,S′)(thiocyanato-N)(triphenylphosphine)nickel(II)

The compounds [Ni(behdtc)₂] (1) and [Ni(behdtc)(NCS)(PPh₃)] (2) (where behdtc = bis(2-ethylhexyl)dithiocarbamate) were synthesized and characterized by elemental analyses, electronic, IR, and NMR (¹H and ¹³C) spectroscopy. UV-vis spectral data are consistent with the formation of square-planar nickel complexes. The N¹³CS₂ carbon signal for [Ni(behdtc)(NCS)(PPh₃)] is observed at 204.4 ppm with an upfield shift of about 3.8 ppm compared with that found in [Ni(behdtc)₂] (208.2 ppm). The observed shielding in [Ni(behdtc)(NCS)(PPh₃)] indicates the effect of PPh₃ on the mesomeric drift of electron density toward nickel through the thioureide C-N bond. This observation is supported by the higher νC-N values observed in the IR spectrum of the complex 2. A single crystal X-ray analysis of complex 2 proved four coordinated nickel in a distorted square-planar arrangement with a S₂NP donor set. A significant asymmetry in the Ni–S bond in 2 (2.1690(10) and 2.2234(10)Å) supports the less effective trans effect of SCN^? over PPh₃. Molecular electrostatic potential surface map shows that there are no possible sites for nucleophilic attack and S atom of thiocyanate is preferred possible site for electrophilic attack.     

Comparative effects of different triazole compounds on antioxidant metabolism of Solenostemon rotundifolius

The effect of different triazole compounds, viz., triadimefon (TDM) and hexaconazole (HEX) treatments on the antioxidant metabolism of Solenostemon rotundifolius Poir., Morton plants was investigated in the present study under pot culture. Plants were treated with TDM at 15 mg l⁻¹ and HEX at 10 mg l⁻¹ separately by soil drenching on 80, 110 and 140 days after planting (DAP). The plants were harvested randomly on 90, 120 and 150 DAP for determining the effect of both the triazoles on non-enzymatic antioxidant contents like ascorbic acid (AA), reduced glutathione (GSH) and -tocopherol (-toc), activities of antioxidant enzymes like superoxide dismutase (SOD) and ascorbate peroxidase (APX). All the analyses were made in leaf, stem and tubers of both control and treated plants. It was found that both these triazole compounds have profound effects on the antioxidant metabolism and caused an enhancement in both non-enzymatic and enzymatic antioxidant potentials under treatments. These results suggest that, the application of triazoles may be a useful tool to increase the antioxidant production in S. rotundifolius and thereby make it an economical food crop.     

A novel and diastereoselective construction of H-pyrazolo[3,2-a]isoquinoline fused spirooxindoles via [3+2] cycloaddition

A one-pot, highly efficient and diastereoselective construction of 1,2-dihyro-10′bH-spiro[indole-3,1′-pyrazole[3,2-a]isoquinoline]-2′-carboxylates via silver triflate-catalyzed [3+2] cycloaddition of N′-(2–alkynylbenzylidene)hydrazide with methyleneindolinones in good to excellent yield has been described. The transformation involves initially a condensation followed by 6-endo-intramolecular cyclization forming dipole which then undergoes [3+2]-cycloaddition with methyleneindolinones and finally, β-hydrogen elimination.     

Effect of Currently Available Nanoparticle Synthesis Routes on Their Biocompatibility with Fibroblast Cell Lines

Nanotechnology has acquired significance in dental applications, but its safety regarding human health is still questionable due to the chemicals utilized during various synthesis procedures. Titanium nanoparticles were produced by three novel routes, including Bacillus subtilis, Cassia fistula and hydrothermal heating, and then characterized for shape, phase state, size, surface roughness, elemental composition, texture and morphology by SEM, TEM, XRD, AFM, DRS, DLS and FTIR. These novel titanium nanoparticles were tested for cytotoxicity through the MTT assay. L929 mouse fibroblast cells were used to test the cytotoxicity of the prepared titanium nanoparticles. Cell suspension of 10% DMEM with 1 × 10⁴ cells was seeded in a 96-well plate and incubated. Titanium nanoparticles were used in a 1 mg/mL concentration. Control (water) and titanium nanoparticles stock solutions were prepared with 28 microliters of MTT dye and poured into each well, incubated at 37 °C for 2 h. Readings were recorded on day 1, day 15, day 31, day 41 and day 51. The results concluded that titanium nanoparticles produced by Bacillus subtilis remained non-cytotoxic because cell viability was >90%. Titanium nanoparticles produced by Cassia fistula revealed mild cytotoxicity on day 1, day 15 and day 31 because cell viability was 60–90%, while moderate cytotoxicity was found at day 41 and day 51, as cell viability was 30–60%. Titanium nanoparticles produced by hydrothermal heating depicted mild cytotoxicity on day 1 and day 15; moderate cytotoxicity on day 31; and severe cytotoxicity on day 41 and day 51 because cell viability was less than 30% (p < 0.001). The current study concluded that novel titanium nanoparticles prepared by Bacillus subtilis were the safest, more sustainable and most biocompatible for future restorative nano-dentistry purposes.     

Aphrodisiac Performance of Bioactive Compounds from Mimosa pudica Linn.: In Silico Molecular Docking and Dynamics Simulation Approach

Plants and their derived molecules have been traditionally used to manage numerous pathological complications, including male erectile dysfunction (ED). Mimosa pudica Linn. commonly referred to as the touch-me-not plant, and its extract are important sources of new lead molecules in drug discovery research. The main goal of this study was to predict highly effective molecules from M. pudica Linn. for reaching and maintaining penile erection before and during sexual intercourse through in silico molecular docking and dynamics simulation tools. A total of 28 bioactive molecules were identified from this target plant through public repositories, and their chemical structures were drawn using Chemsketch software. Graph theoretical network principles were applied to identify the ideal target (phosphodiesterase type 5) and rebuild the network to visualize the responsible signaling genes, proteins, and enzymes. The 28 identified bioactive molecules were docked against the phosphodiesterase type 5 (PDE5) enzyme and compared with the standard PDE5 inhibitor (sildenafil). Pharmacokinetics (ADME), toxicity, and several physicochemical properties of bioactive molecules were assessed to confirm their drug-likeness property. Molecular dynamics (MD) simulation modeling was performed to investigate the stability of PDE5–ligand complexes. Four bioactive molecules (Bufadienolide (−12.30 kcal mol⁻¹), Stigmasterol (−11.40 kcal mol⁻¹), Isovitexin (−11.20 kcal mol⁻¹), and Apigetrin (−11.20 kcal mol⁻¹)) showed the top binding affinities with the PDE5 enzyme, much more powerful than the standard PDE5 inhibitor (−9.80 kcal mol⁻¹). The four top binding bioactive molecules were further validated for a stable binding affinity with the PDE5 enzyme and conformation during the MD simulation period as compared to the apoprotein and standard PDE5 inhibitor complexes. Further, the four top binding bioactive molecules demonstrated significant drug-likeness characteristics with lower toxicity profiles. According to the findings, the four top binding molecules may be used as potent and safe PDE5 inhibitors and could potentially be used in the treatment of ED.