Stability-Indicating LC Method for Analysis of Lornoxicam in the Dosage Form

A simple, rapid, and precise method has been developed for quantitative analysis of lornoxicam (Lxm) in pharmaceutical dosage forms. Chromatographic separation of Lxm and its degradation products was achieved on a C₁₈ analytical column with 0.05% (v/v) aqueous trifluoroacetic acid–acetonitrile, 70:30 (v/v), as mobile phase. The flow rate was 1.0 mL min^?1, the column temperature 30 °C, and detection was by absorption at 295 nm using a photodiode-array detector. The number of theoretical plates and tailing factor for Lxm were 6,577 and 1.03, respectively. Lxm was exposed to thermal, photolytic, hydrolytic, and oxidative stress, and the stressed samples were analysed by use of the proposed method. Peak homogeneity data for Lxm in the chromatograms from the stressed samples, obtained by use of the photodiode-array detector, demonstrated the specificity of the method for analysis of Lxm in the presence of the degradation products. The linearity of the method was excellent over the range 10–200 μg mL^?1 Lxm. The correlation coefficient was 0.9999. Relative standard deviations of peak areas from six measurements were always less than 2%. The proposed method was found to be suitable and accurate for quantitative analysis of Lxm and study of its stability.     

Fractal pattern growth simulation in electrodeposition and study of the shifting of center of mass

We presented simulation of fractal pattern in electrodeposition (Diffusion limited aggregation) using concept of off lattice walk.It is seen that the growth patterns are based on a parameter called ‘bias’. This parameter ‘bias’ controls the growth of patterns similar to that of electric field in electrodeposition technique. In present study the fractal patterns are grown for different values of ‘bias’. Dendritic patterns grown at lower value of ‘bias’ comprises open structure and show limited branching. As the bias is increased the growth tends to be dense and show more crowded branching. Box counting was implemented to calculate fractal dimension. The structural and textural complexities and are compared with the experimental observations.It was also noted that in the evolution of DLA patterns, the center of mass of the growth is shifted slightly. We tracked the position of the center of mass of simulated electro deposits under different electric field conditions. The center of mass exhibit random walk like patterns and it wanders around the origin or the starting point of the growth.     

Facile synthesis of α-aminonitriles

α-Aminonitriles were prepared by reacting α-trimethylsilyloxynitriles with various amines in methanol. The silyloxynitriles were obtained by condensing a wide range of aldehydes (aliphatic, aromatic and heteroaromatic) with trimethylsilyl cyanide (TMSCN) in the presence of a catalytic amount of zinc iodide.     

Heterolytic cleavage of homoallylic alcohols—I: Fragmentation of 6-hydroxycamphene derivatives

Heterolytic fragmentation of homoallylic alcohols incorporated in a bicyclo[2,2,1]heptane system with electrophilic reagents or that of the corresponding epoxides with acids, is described. A short route, via this fragmentation, to synthon 25, potentially useful in the syntheses of cis-jasamone and prostanoids, is reported.     

Diacetoxyiodobenzene-mediated oxidative addition of 1,3-dicarbonyl compounds to olefins: an efficient one-pot synthesis of 2,3-dihydrofuran derivatives

A variety of olefins react with -dicarbonyl compounds at 0°C in the presence of diacetoxyiodobenzene to afford highly substituted 2,3-dihydrofuran derivatives in good to excellent yields.     

The effect of temperature on the extraction of plutonium(IV) from nitric acid by tri-n-butyl phosphate

The extraction of Pu(VI) from varying concentration of nitric acid into TBP in dodecane was studied at different temperatures in the range 20–60°C. From the distribution coefficient data, the enthalpy changes for the extraction of Pu(VI) under different conditions were determined. All the data obtained showed that the extraction of Pu(VI) from nitric acid into TBP is exothermic in nature. An attempt was made to evaluate the thermodynamic free energy and entropy changes.     

Rearrangement of 3,3-ethylenedioxy-isobornyl tosylate: an efficient new synthesis of 7-ketocamphene

A new efficient route to 7-ketocamphene, involving as the key-step, a solvolytic-type rearrangement of 3,3-ethylenedioxyisoborneol (via tosylate) is described. A side-reaction arising from acid-catalyzed fragmentation of 7,7-ethylenedioxycamphene was encountered and has been investigated further. A Baeyer-Villiger type oxidation with dioxane hydroperoxides in the presence of an acid has been noted.     

Synthetic studies towards the benzophenone precursor for balanol

Synthesis of 4-carboxy-2,6-dimethoxyphenyl 2′-carboxy-6′-methoxyphenyl ketone, an important precursor for balanol's benzophenone portion, has been achieved via a short and efficient route in three steps using ortho-lithiation as the key step. In another approach aromatization of 2-(2′-methoxy-6′-methylbenzoyl)-5-methyl-1,3-cyclohexanedione afforded benzophenone precursor 2,6-dimethoxy-4-methylphenyl 2′-methoxy-6′-methylphenyl ketone along with the formation of substituted xanthone.     

Preparation of transparent conducting ZnO:Al coating using hot wall deposition technique

Aluminium-doped zinc oxide thin films were grown on glass substrates using hot wall deposition technique. The method involved evaporation of high purity ZnO and Al from respective sources surrounded by alumina cylinder held at high temperature. The additional thermal energy supplied by the hot wall to the particles colliding on it helps in its migration resulting in highly uniform films. XRD studies show the growth of c-axis oriented near single phase ZnO films having about 90% transmittance in the visible range and resistivity of the order of 10⁻⁴Θ cm.     

Study of bonding in some nickel complexes of isonitrosoketones

X-ray K-absorption edge analysis of nickel in some nickel complexes of isonitrosoketones has been carried out using a 400-mm bent crystal spectrometer. The analysis has been used to deduce information regarding the mode of bonding, the magnetic behaviour and the coordination of Ni in the complexes. On the basis of the results obtained, it has been concluded that Ni ions in Ni(HMAO)₂; have square planar structure whereas Ni ions in Ni(HTGA)₂ have tetrahedral structure. On the other hand Ni ions in Ni(EINA)₂; and Ni(INACA)₂, are surrounded by octahedra. Ni ions in Ni(INACA)₂ are in the valence state higher than two and appear to be paramagnetic.