Structural Isomers of Bis(diphenylarsino)methane‐dichloroplatinum(II)

From a range of preparative methods, three geometric isomers of bis(diphenylarsino)methane‐dichloroplatinum(II) have been isolated, viz. cis‐PtCl₂(dpam), trans, trans‐Pt₂Cl₄(dpam)₂ and cis, trans‐Pt₂Cl₄(dpam)₂. Their structures were determined by single‐crystal X‐ray diffraction.     

HPLC Determination of Letrozole in Plasma Using Fluorescence Detection: Application to Pharmacokinetic Studies

A simple, rapid and sensitive HPLC method has been developed and validated for the analysis of letrozole in human plasma. The separation was achieved on a monolithic silica column using acetonitrile–phosphate buffer. A fluorescence detector was used for the quantitation with excitation and emission wavelengths at 230 and 295 nm. The assay enables the measurement of letrozole for therapeutic drug monitoring with a minimum quantification limit (LOQ) of 0.5 ng mL^?1. The method involves a simple, one-step extraction procedure with complete recovery. Calibration was linear over the concentration range 0.5–80 ng mL^?1. The coefficients of variation for inter-day and intra-day assay were found to be less than 8%.     

Practical application of new catalytic methods: a concise synthesis of a potent PDE IV inhibitor

An efficient synthesis of a potent PDE IV inhibitor 1 is described. The synthesis is highlighted by two practical and efficient catalytic reactions: a highly selective catalytic palladium mediated carbonylation of the pyridine side chain and an efficient palladium-catalyzed Suzuki-Miyaura coupling of a chloropyridine-N-oxide.     

Immobilization of a nickel complex onto functionalized Fe3O4 nanoparticles: a green and recyclable catalyst for synthesis of 5-substituted 1H-tetrazoles and oxidation reactions

Research on Chemical Intermediates - In the present research, a magnetically recoverable catalyst was easily prepared by anchoring nickel onto the surface of organically modified magnetite...     

Three component reactions：An efficient and green synthesis of 3, 4-dihydropyrimidin-2-(1H)-ones and thiones using silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate

An environmentally benign aqueous protocol for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones and thiones promoted by a green catalyst,silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate,has been developed.The use of nontoxic,thermally stable and inexpensive amino acid catalyst makes the process simple with minimal amount of chemical waste.Compared with classical Biginelli reaction conditions,this new method has the advantages of high yields and simple workup procedures.     

Optimal free-defect synthesis of four-bar linkage with joint clearance using PSO algorithm

This paper presents the design of planar four-bar linkages free of order, branch and circuit defects, for the purpose of path generation, having clearances at one, two, three or all of its joints. Joint clearance is treated as a massless virtual link and its direction is known by the direction of the joint force. A Particle Swarm Optimization based algorithm is given here to solve this highly nonlinear optimization problem with some constraints, namely; the Grashof’s and free of the foregoing defects conditions. An example is included in which the optimal problem is solved for different cases; namely planar four-bar linkage having clearances at one, two, three, all of the joints and without clearance. For all the designs, the generated paths, the errors and the directions of the virtual links are plotted and are compared. Finally, we compare the optimal designs with reality.     

Podophyllotoxin extraction from Linum usitatissimum plant and its anticancer activity against HT‐29, A‐549 and MDA‐MB‐231 cell lines with and without the presence of gold nanoparticles

In recent years, gold nanoparticles (Au‐NPs) have been taken into consideration in nanomedicine due to their excellent biocompatibility, chemical stability and promising optical properties. In this research, podophyllotoxin conjugated with gold nanoparticles (Au‐NPs‐POT) was synthesized and the conjugation of POT with Au‐NPs was confirmed using scanning electron microscopy, mass spectrometry and Fourier transform infrared spectroscopy. The anticancer effects of the product on preclinical models of lung, colon and breast cancers were investigated using MTT test. The analyses showed a direct dose–response relationship. It was found that higher concentrations of POT have more positive effects on the inhibition of cancer cell growth. At POT concentrations of 1, 2.5, 5, 7.5, 10, 15 and 20 ng ml^?1, approximately 50% of the growth of colorectal, lung and breast cancer cell lines was inhibited, while similar results were obtained in the presence of 1, 2, 3, 4 and 5 μg ml^?1 Au‐NPs‐POT. Au‐NPs‐POT exhibited the lowest cytotoxicity due to the presence of POT. The anticancer feature of Au‐NPs‐POT proved the potential to develop better anticancer therapeutics and to open new avenues for treatment of cancers.