Structural studies of diethyltin(IV) derivatives and their biological aspects as potential antitumor agents against Agrobacterium tumefacien cells

A series of new diethyltin(IV) derivatives of substituted phenyl acrylates have been synthesized and characterized by elemental analysis, IR, multinuclear NMR (¹H, ¹³C, ¹⁹F and ¹¹⁹Sn) and X‐ray single crystal analysis. X‐ray single crystal diffraction study of complex 8 has shown the formation of secondary O···Sn, F···H and H···O intermolecular interactions. These complexes proved to be good antitumor agents. The antitumor properties are presumably due to the intercalative mode of interaction of these complexes with the tumor cells' DNA. Copyright © 2011 John Wiley & Sons, Ltd.     

Production, Purification, and Characterization of Exoglucanase by Aspergillus fumigatus

Fungi are considered good producers of industrially valuable enzymes with higher enzymatic activities. Among these cellulases are group of extracellular enzymes commonly employed in many industries for the hydrolysis of cellulolytic material. Aspergillus fumigatus produced exoglucanase having high enzymatic activity (83 U/gds) during the solid-state fermentation of wheat straw under optimum physical and nutritional conditions. Maximum production was obtained after 72 h of fermentation, at 55 °C temperature, pH 5.5, 80 % moisture level, and 2 mL fungal inoculum. Production was further increased by the addition of fructose (0.3 %) as additional carbon source, peptone (0.4 %) as nitrogen source, Tween-80 (0.3 %) as surfactant, and ammonium sulfate (0.2 %) in media. Exoglucanase was 2.30-folds purified by adding 40 % ammonium sulfate with volumetric activity 95.4 U/gds and specific activity 14.74 U/mg. Further, it was 5.18-folds purified by gel filtration chromatography with volumetric activity 115.2 U/gds and specific activity 33.10 U/mg. Purified exoglucanase has maximum activity at 55 °C and pH 4.8 using 1 % Avicel aqueous solution as substrate. The K _m and V _max were 4.34 mM and 7.29 μM/min, respectively. Calcium, magnesium, and zinc ions have positive effect on exoglucanase activity.     

Tumor‐Promoting Diterpene Esters from Latex of Euphorbia cauducifolia L.

Tumor‐promoting characteristics of seven esters, 1 – 7 , obtained from the latex of Euphorbia cauducifolia L. was appraised by carrying out NMRI mice back skin. The structures of 1 – 7 were elucidated by spectroscopic techniques like ¹H‐ and ¹³C‐NMR, 2D‐NMR (HMQC, HMBC, HOHAHA (homonuclear Hartmann–Hahn), NOESY, and NOE), FT‐IR, UV, and MS as esters of 17‐hydroxyingenol, namely 17‐[(2Z,4E,6Z)‐deca‐2,4,6‐trienoyloxy]ingenol ( 1 ), 3‐O‐angeloyl‐17‐[(2Z,4E,6Z)‐deca‐2,4,6‐trienoyloxy]ingenol ( 2 ), 3‐O‐acetyl‐20‐O‐angeloyl‐17‐hydroxyingenol ( 3 ), 17‐(acetyloxy)‐3‐O‐angelyl‐ingenol ( 4 ), 20‐O‐acetyl‐3‐O‐angeloyl‐17‐hydroxyingenol ( 5 ), 3‐O‐angelyl‐17‐(benzoyloxy)ingenol ( 6 ) and 20‐O‐acetyl‐3‐O‐angelyl‐17‐(benzoyloxy)ingenol ( 7 ). Compounds 1 – 4 were isolated for the first time, whereas 5 – 7 are known metabolites but detected for the first time in this plant. Biological investigations revealed that these compounds are tumor promoters.     

Crystallographic report: Polymeric [3‐(triphenylgermyl)‐3‐o‐methoxyphenylpropionato]trimethyltin(IV)

The polymeric chains of [Sn(CH₃)₃(C₂₈H₂₅O₃Ge)]_n contain trimethyltin moieties bridging two neighboring 3‐(triphenylgermyl)‐3‐o‐methoxypropionate ligands via carboxyl groups. The germanium atom has a distorted tetrahedral geometry and the tin atom has a distorted trigonal‐bipyramidal geometry, the latter with three methyl groups in the equatorial plane and oxygen atoms defining the axial positions. Copyright © 2005 John Wiley & Sons, Ltd.     

Synthesis,spectroscopic exploration,biocidal activities,and crystal structures of 3‐(3‐fluorophenyl)‐2‐phenylpropenoic acid and trimethyltin(IV) complex

The ligand, 3‐(3‐fluorophenyl)‐2‐phenylpropenoic acid, [C₁₅H₁₁FO₂] ( I ) was prepared by reacting equimolar amount of phenyl acetic acid with 3‐fluorobenzaldehyde (1:1) using Perkin condensation method. The trimethyltin(IV) carboxylate, [Me₃SnO₂FH₁₀C₁₅] ( II ) was synthesized by refluxing an equimolar (1:1) mixture of trimethyltin chloride and silver salt of the ligand acid, [C₁₅H₁₀FO₂Ag] ( Ia ). The ligand and complex both were characterized by elemental analysis, IR, mass, ¹H NMR, and X‐ray crystallographic data. On the basis of ¹H NMR data, (²J[^117/119Sn, ¹H] and C Sn C bond angle), it is concluded that the environment around the tin atom in solution is tetrahedral. The Infrared spectroscopic results showed that trimethyltin(IV) derivative has 5‐coordinated polymeric structure with bridging carboxylate groups in the solid state, which has been confirmed by the X‐ray crystallographic data. The crystal of ligand acid ( I ) is triclinic with space group Pbar1. However, the crystal of the complex ( II ) is monoclinic with space group C_2/c. The geometry around the tin atom is distorted trigonal bipyramid with O(1) and O(2) atoms in apical positions. The ligand ( I ) and complex ( II ) were also tested for their biocidal activities. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:398–406, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20032     

On certain analytic functions associated with Ruscheweyh derivatives and bounded Mocanu variation

Using Ruscheweyh derivative and convolution operator, we introduce a new subclass of analytic functions defined in the unit disc. Some inclusion results, a radius problem and some other interesting properties of this class are investigated.     

Tributyltin(IV)[3‐(3′,5′‐dimethylphenylamido)propanoate] as a potent HCV inhibitor,its delivery study,controlled release and binding sites using CTAB as a standard cell membrane

Gaussia luciferase assay was used to measure the anti‐hepatitis C (anti‐HCV) potency of tributyltin(IV)[3‐(3′,5′‐dimethylphenylamido)propanoate] in infected Huh 7.5 cells (human hepatocellular cell). Interaction of the organotin(IV) complex with cetyl N,N,N‐trimethylammonium bromide (CTAB) micelles was studied using UV–visible and steady‐state florescence spectroscopy. The anti‐HCV study showed a log IC₅₀ value of 0.96 nm for the complex. The complex–CTAB interaction parameter showed that partition of the complex from bulk water to the CTAB micelle was a spontaneous process, and the red shift in visible spectra of the complex confirmed its increased solubility into micelles. Copyright © 2013 John Wiley & Sons, Ltd.     

Organotin(IV) 4-nitrophenylethanoates: Synthesis, structural characteristics and intercalative mode of interaction with DNA

Four new organotin(IV) carboxylates, [Bu₂SnL₂] (1), [Et₂SnL₂] (2), [Bu₃SnL]_n (3), [Me₃SnL]_n (4), where L = 4-nitrophenylethanoates, were synthesized and characterized by elemental analysis, FT-IR and multinuclear NMR (¹H and ¹³C). Spectroscopic results authenticated the coordination of ligand to the organotin moiety via COO group while X-ray single crystal analysis revealed bidentate chelating mode of coordination of ligand in complex 2 and a bridging behavior in complexes 3 and 4. Cyclic voltammetric (CV) technique was used to evaluate the electrochemical, kinetic and thermodynamic parameters of complexes 1-4, interacting with DNA. The linearity of the plots between the peak current (I) and the square root of the scan rate (ν^1/2) indicated the electrochemical processes to be diffusion controlled. The diffusion coefficients of the free (D_f) and DNA bound forms (D_b), standard rate constants (ks) and charge transfer coefficients (α) were determined by the application of Randle–Sevcik, Nicholson and Kochi equations. Furthermore, the binding constants evaluated from voltammetric data revealed the following increasing order of binding strength: 2 < 1 < 4 < 3. For 1 and 2, the activity against prostate cancer cell lines (PC-3) was found consistent with the order obtained from voltammetric behavior.     

Some applications of Miller-Mocanu lemma on certain classes of meromorphic functions

In this paper, making use of a linear operator we introduce and study certain new classes of meromorphic functions. We derive some inclusion results. These classes contain many known classes as a special case.