Journal of the Iranian Chemical Research
Volume:3 Issue: 2, Spring 2010

A simple, sensitive and accurate method for spectrophotometric determination of Dalacinphosphate has been established. The method is based on the reduction of atomic absorption calcium ion by phosphate. Because, there is a phosphate mole in every Dalacin mole structure and with measurement of phosphate, Dalacin is beyond measurement too. Therefore, the reaction between acidic hydrolysis products of antibiotics with the mixture of calcium ion evaluated for the spectrophotometric determination of mentioned drug in formulations. Experimental parameters related to the performance of atiomic absorption spectrometry (AAS), such as concentration of calcium ion, reaction time and temperature were investigated and optimized. Under the optimized conditions, the limit of detection (3σB) and relative standard deviation (RSD, n=4) were 1.75 μg mL-1 and 1.4 %, respectively. The results obtained agreed with those obtained by the USP method.

Condensation of aromatic aldehydes with benzoyl acetone under specified conditions yielded two series of polycarbonyl compounds in which the keto group is attached to olefinic linkage. Spectral and analytical data revealed the formation of an unsaturated triketone from pyridine-3- carbaldehyde and unsaturated diketone from furfural, salicylaldehyde and 2- hydroxynaphthaldehyde. Analytical, IR, 1H NMR and mass spectral data suggest neutral bidentate coordination for the unsaturated triketone with Ni(II), Cu(II) and Zn(II) ions. In the [ML2] complexes of the unsaturated diketones, the intramolecularly hydrogen bonded enol proton is replaced by the metal ion.

A new series of transition metal complexes of Co(II), Ni(II), Cu(II) and Zn(II), has been synthesized from the Knoevenagel condensate Schiff base ligand(L) derived from β-ketoanilide and furfural with o-phenylenediamine and diethylmalonate. Structural features were determined by spectral and analytical techniques. Square-planar geometry has been adopted by the complexes except cobalt complex which has an octahedral geometry. The synthesized ligand and its complexes were screened for their anti-inflammatory activity in male albino rats (Carrageenan-induced rat paw oedema model). Among these complexes, copper complex shows significant anti-inflammatory activity. It exhibits significant dose dependent activity in acute inflammation. The doses of 100 and 200 mg kg-1 bw produced 38.3 % and 42.8 % inhibition respectively after 3 h as compared with that of the standard drug (indomethacin) which showed 48.5 % inhibition. The in vitro antimicrobial activity of the ligand and its complexes was monitored by disc diffusion method. It has been found that complexes have higher antimicrobial activity than that of free ligand.

The thermal decomposition of 86 % vinyl chloride 14 % vinyl acetate copolymer was studied by the conductometry technique in the presence of nitrogen. The kinetics of stability and thermal degradation of vinyl chloride- co- vinyl acetate (PVC- co- PVAc) copolymer with copper, copper oxide and tricalcium dicitrate (st) were investigated at various temperatures (150- 180 oC ) in solution. The rate coefficients for the degradation of the copolymer were determined. The energies of activation, determined from the temperature dependence of the rate coefficients for copolymer alone was 63.536 kJ mol-1 and in the presence of copper, copper oxide and tricalcium dicitrate were 44.224, 55.594 and 110.332 KJ mol-1, respectively. The results show that thermal stability was increased in the presence of tricalcium dicitrate, but its thermal stability was decreased in the presence of copper and copper oxide.

Synthesis and cation selectivity of 25, 27, dipropoxy-26, 28, Di-propoxy 5, 11, 17, 23, ptert- butyl Calix[4]arene are studied in acetonitrile solution. The stability constants of different complexes of Calixarene (as a ligand) with alkali metal cations are determined at 25 °C by using spectrophotometric technique.On the basis of calculations, complexation of Calixarene with Cs and Li are more favored than others. In all cases, it has been shown to form exclusively 1:1 (metal ion to ligand) complex with alkali cations in experimental condition.

MCM-41-R-SO3H catalyzed one-pot synthesis of 1,8-dioxo-octahydroxanthenes is reported under reflux conditions. The catalyst is easily prepared, highly stable, very simple to handle and recycled for five times without loss of significant activity.

Waste Low density polyethylenes (LDPE) represent a source of energy and valuable chemicals, were pyrolysed catalytically in a batch reactor under atmospheric pressure. Calcium carbide was used as a catalyst to explore its effect on pyrolysis product distribution. The effect of temperature, amount of catalyst and time on the yields of the pyrolysed products was investigated. The effect of catalyst on the liquid yield was also studied. The results demonstrate that temperature has a promising effect on the yield; however high temperature, as well as high catalyst loading, caused a decline in liquid yield. The liquid obtained from catalytic pyrolysis were also characterized by physical and chemical tests. Among the physical tests Density, Specific gravity, API gravity, Viscosity, Kinematic viscosity, Aniline point, Flash point, Watson Characterization Constant, Freezing Point, Diesel Index, Refractive Index, Gross calorific value, Net calorific value and ASTM Distillation were determined according to IP and ASTM standard methods for fuel values. From the physical tests it was observed that the results for the liquid fractions are comparable with the standard results of physical tests for gasoline, kerosene and diesel fuel oil. Phenols and carbonyls were quantitatively determined by spectrophotometric methods using Folin-Denis and Phenyl Hydrazine reagents respectively. The components of different hydrocarbons in the oil mixture were separated by using column chromatography and fractional distillation followed by characterization with FT-IR spectroscopy.

An improved and facile preparation of 3,7-dinitro-1,3,5,7-tetraazabicyclo [3,3,1] nonane (DPT) has been developed starting from urea. In the procedure DPT was synthesized via N,N’-dinitrourea (DNU) as intermediate and various operating parameters such as temperature, pH and molar ratio of reagents have been optimized to give maximum yield of the desired product. The low cost method is concise, operationally simple and offers high purity and satisfactory yield of DPT.