Potential Xanthine Oxidase Inhibitory Activity of Endophytic Lasiodiplodia pseudotheobromae

Xanthine oxidase is considered as a potential target for treatment of hyperuricemia. Hyperuricemia is predisposing factor for gout, chronic heart failure, atherosclerosis, tissue injury, and ischemia. To date, only two inhibitors of xanthine oxidase viz. allopurinol and febuxostat have been clinically approved for used as drugs. In the process of searching for new xanthine oxidase inhibitors, we screened culture filtrates of 42 endophytic fungi using in vitro qualitative and quantitative XO inhibitory assays. The qualitative assay exhibited potential XO inhibition by culture filtrates of four isolates viz. #1048 AMSTITYEL, #2CCSTITD, #6AMLWLS, and #96 CMSTITNEY. The XO inhibitory activity was present only in the chloroform extract of the culture filtrates. Chloroform extract of culture filtrate #1048 AMSTITYEL exhibited the highest inhibition of XO with an IC₅₀ value of 0.61 μg ml^?1 which was better than allopurinol exhibiting an IC₅₀ of 0.937 μg ml^?1 while febuxostat exhibited a much lower IC₅₀ of 0.076 μg ml^?1. Further, molecular phylogenetic tools and morphological studies were used to identify #1048 AMSTITYEL as Lasiodiplodia pseudotheobromae. This is the first report of an endophytic Lasiodiplodia pseudotheobromae from Aegle marmelos exhibiting potential XO Inhibitory activity.     

Structural and optical properties of La and Gd substituted Bi4 − x M x V2O11 − δ (0.1 ≤ x ≤ 0.3)

Bi_4???x M _x V₂O_11???δ (M?=?La, Gd; 0.1?≤?x?≤?0.3) is synthesised by a solid state reaction method to study the effect of La³⁺ and Gd³⁺ substitution for Bi on the structural and optical properties. The as-prepared samples are characterised by X-ray diffraction, Fourier transform infrared analysis, UV–visible spectroscopy, scanning electron microscopy and energy-dispersive spectroscopy. The refinement results confirmed that even substituted samples exhibit monoclinic structure with space group C2/m. The parameters like band gap energy; Urbach energy has been calculated from the UV–visible spectra. It has been observed that even substitution at the bismuth site by isovalent cations decreases the energy band gap. The lowest observed band gap is 1.86 eV for Bi_3.9La_0.1V₂O_11???δ . The grain size and defects were observed to increase with increasing substitution along with the amount of secondary phase.     

Erratum to: “Syntheses and characterisation of chloro(<Emphasis Type=Italic>η</Emphasis>3-allyl) dicarbonylmolybdenum(II) complexes of chiral and achiral ditertiaryphosphines”

The original version of the article was published in Cent. Eur. J. Chem. 10(1) (2012), pp 165–171. Unfortunately, the original version of this article contains mistakes in the affiliation section. Dr Devendra D. Pathak’s affiliation is Department of Applied Chemistry, Indian School of Mines, Dhanbad 826 004, India. Dr Pramesh N. Kapoor’s affiliation is Department of Chemistry, University of Delhi, Delhi 110 007, India.     

Fluorescent zinc-terpyridine complex containing coordinated peroxo counter ion in aqueous medium

We describe a mixed ligand-zinc(d ¹⁰ ) complex containing coordinated peroxo ion and 2,2′2″-terpyridine and exhibiting fluorescence in the visible region (473 nm) on excitation at 390 nm in aqueous medium at room temperature. We also discuss the unusual phenomenon of enhancement of this fluorescence intensity on addition of some transition metal ions(3d ⁵, 3d¹⁰, 4d⁰and3d ⁹electronic configurations).     

Synthesis, structural and spectroscopic characterization, catalytic properties, and thermal transformations of new cyclic di- and trisiloxanediolato tantalum complexes

The reaction between Ta(OEt)5 and 1,1,3,3-tetramethyl-1,3-disiloxanediol, (HOSiMe2OSiMe2OH), leads to new siloxy complexes in which the dimeric nature of Ta(OEt)5 is maintained with both bridging ethoxide and disiloxanediolato bridges. With equal amounts of the reagents, two terminal OEt groups are replaced to form [Ta(OEt)2]2(mu-OEt)2(mu-OSiMe2OSiMe2O)2, 1, whereas with an excess of diol, the remaining terminal OEt groups are also replaced but with a trisiloxanediolato unit to form [Ta(OSiMe2OSiMe2OSiMe2O)]2(mu-OEt)2(mu-OSiMe2OSiMe2O)2, 2. Complexes 1 and 2 catalyze the transformation of HOSiMe2OSiMe2OH to polysiloxanes. Thermal treatment of 1 results in the formation of a 1:2 mixture of Ta2O5/SiO2; no new phases are observed. The molecular structures of 1 and 2 are confirmed by X-ray crystallography.     

A Theorem of Truemper

Received November 5, 1997     

Melting temperature of H<Subscript>2</Subscript>, D<Subscript>2</Subscript>, N<Subscript>2</Subscript> and CH<Subscript>4</Subscript> under high pressure

The melting temperatures of H₂, D₂; N₂ and CH₄ are analysed. The computed results are in very good agreement with the experimental data in each solid. Further, the analysis indicates the presence of the melting maximum in these solids.