a borítólapra  Súgó epa Copyright 
European chemical bulletinVol. 2., No.8. (2013)

Tartalom

Classical chemical sciences

  • Andreia Corciova :

    Bupivacaine hydrochloride is an anesthetic with prolonged duration of action. The aim of this study was to develop a fast, simple and sensitive spectrophotometric method for the determination of bupivacaine in pharmaceutical preparation. The maxim absorbance was finding at 262 nm. At the same time, a validation study was conducted for the proposed method, in accordance with the bioanalytical method validation guidelines. The studied validation characteristics showed that the proposed method can be successfully applied to pharmaceutical preparations analysis.

    Keywords: bupivacaine hydrochloride, quantitative assay, UV – Vis spectrophotometry, validation

  • A. Krishnaveni ,
    S. Rajendran ,
    M. Pandiarajan :

    Corrosion resistance of 18 carat gold in artificial saliva, in the absence and presence of a Tablet, namely, Almox 250 DT has been evaluated by polarization study. It is observed that when 50 ppm of Almox is added to analytical saliva, linear polarization resistance of 18 carat gold increases, in presence of 50 ppm of 18 carat gold. Similar observation is made in presence of 200 ppm of Almox also. Hence it is concluded that people having orthodontic wires made of 18 carat gold, can take the Tablet Almox 250 DT without any hesitation, because in its presence corrosion resistance of 18 carat gold increases.

    Keywords: corrosion resistance of metals, 18 carat gold, synthetic saliva, orthodontic wires, Amoxicillin trihydrate

  • Asieh Yahyazadeh ,
    Zahra Ghasemi :
    Synthesis of unsymmetrical thiourea derivatives573-575en [88.55 kB - PDF]EPA-02286-00018-0030

    A series of thiourea derivatives have been synthesized. Thiourea derivatives show a broad spectrum of biological activities such as antibacterial, antiviral, anticancer, anticonvulsion, analgesic an HDL-elevating. Ethyl isothiocyanate and aromatic amines were mixed and stirred at room temperature in acetone for 15 h to give the corresponding thioureas in high yields. Their structures were confirmed by IR and 1H-NMR. By addition e-donor groups to aromatic amines, thioureas were synthesized in high yields.

    Keywords: substituted anilines, ethyl isothiocyanate, unsymmetrical thiourea derivatives

  • Basim H. Asghar ,
    S. Sheik Mansoor ,
    V. Saleem Malik :

    The kinetics of oxidation of several para- substituted benzaldehydes by imidazolium fluorochromate (IFC) has been studied in the presence of p-toluenesulphonic acid (TsOH) in different (hydrogen bond donor and hydrogen bond acceptor) organic solvents. The reaction was run under pseudo-first-order conditions. Various thermodynamic parameters for the oxidation have been reported and discussed along with the validity of isokinetic relationship. The rate data showing satisfactory correlation with Kamlet-Taft solvatochromic parameters (α, β and π*) which suggests that the specific solute-solvent interactions play a major role in governing the reactivity, and the observed solvent effects have been explained on the basis of solute-solvent complexation.

    Keywords: imidazolium fluorochromate , p-substituted benzaldehydes, solvent effect, oxidation kinetics

  • Karam A. El-Sharkawy ,
    Rehab A. Ibrahim :

    This work has been carried out to investigate the utility of arylidene acetoacetanilides 3a, b in heterocyclic synthesis. Thus, the synthesis of pyridine derivatives 6a, b, 8a-d, 12a, b were done by the reaction of arylidine derivatives 3a, b with activated methylene groups 4a, b also synthesis of compounds 15, 21a, b, 22a, b were carried out via the reaction of compound 12a with benzaldehyde (2a) and reaction of arylidine derivatives 3a, b with ethylcyanoacetate (4b) in addition to reaction of compound 21a with either benzaldehyde (2a) or salicylaldehyde (2c) respectively. Isoquinoline derivative 14 was afforded via the reaction of compound 12a with malononitrile (4a). Thieno[3,4-c]pyridine derivatives 10, 19 were afforded via the reaction of 2-pyridone derivatives either 8a or 12a with elemental sulphur respectively, pyrazolo[3,4-b]pyridine drivatives 18a, b were synthesized through the reaction of compound 12a with either hydrazine hydrate or phenylhydrazine 16a, b. Finally pyrido[3,4-d]pyridazine derivatives 25a, b were produced via the reaction between compound 21a and aryldiazonium chlorides 23a, b. The biological potentialities of the prepared compounds has been examined and evaluated as antitumor agents. All compounds showed significant growth inhibitory effect.

    Keywords: Arylidenes, pyridines, thieno[c]pyridines, benzo[c]pyridines, antitumor activity

  • Rafat M. Mohareb ,
    Abdelgawad A. Fahmy :

    This work has been carried out to investigate some reactions of 4,5,6,7-tetrahydrobenzo[b]thiophene derivatives 1a,b to give synthesis a series of novel heterocyclic products like N-ethoxymethino derivatives (2a, 2b), N-phenylaminomethino derivatives (3a, 3b), hydrazine derivatives (5a-d), pyrazole derivatives (7a-d, 10a-d, 11a, 11b) and N-methinonitrilo derivatives (9a-d). The antitumor evaluation of the newly synthesized compounds against the three human tumor cells lines namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) showed that some of these compounds exhibit much higher inhibitory effects towards the three tumor cell lines than the positive control doxorubicin. Moreover, they were tested against normal cells namely diploid normal human fibroblast (WI-38), Normal prostate epithelial cells (PrEC) and normal human mucosal epithelial cells (NCM 460). The anti-leishmanial evaluations of the obtained compounds were also performed. Compounds 7d and 10b were the most active towards tumor cell lines while compounds 3a, 3b, 9b and 9d were the most active compounds as anti-leishmanial. Docking of these most active compounds was demonstrated.

    Keywords: tetrahydrobenzo[b]thiophene, pyrazole, human tumor cell lines, normal cell lines, anti-leishmanial agents

Materials and environmental chemistry

  • Sanjay Prasad Gupta :

    Climate is the act of all atmospheric events such as rainfall, temperature, wind, air pressure and humidity etc. In recent years, the alterations about natural environment and climate observed in Chhattisgarh state negatively affected the monumental buildings, the cultural riches of the state that they have been worn out by various natural effects for a long time. However, since monumental buildings have great importance due to their identity of transferring old era information to the future generations, there should be taken special precautions against deteriorations on the monumental buildings. Climate-related deteriorations on the monumental buildings resulted from temperature differences between summer-winter and day-night, water movement at the building due to capillarity, abrasive effects of rain water, salt and some chemicals involved in water, particles carried by wind and air pollution. The deteriorations occurred on the monumental buildings due to climate changes have investigated for Chhatisgarh and the deterioration effects on construction materials have been discussed.

    Keywords: Monument, Climate, Climate Impacts, Historical Buildings, Deterioration.

  • Ajaya Kumar Singh ,
    Swati Mehra ,
    Gautam Sheel Thool :

    The CuS thin films were deposited on glass substrates using the chemical bath deposition technique at 65 °C temperature from aqueous solutions of copper sulphate and thiourea in which tartaric acid solution were employed as the complexing agent. HRXRD studies reveal covellite CuS, having hexagonal primitive crystal structure. AFM studies shows morphology of CuS thin film as spherical particles, and spiky cones showing probability of nanorod formation of CuS. The grains are distributed homogeneously with a pattern consistent with polycrystalline film. Lower value of RMS value for CuS 8 sample of thin film (15.5907 nm) shows that less light is scattered by an optical surface, and hence better the surface quality of thin film. Absorbance of thin film observed between 300-350 nm. The highest transmittance of the as-grown film in the entire wavelength of interest was recorded as 50 %.

    Keywords: Atomic force microscopy, Chemical bath deposition, CuS, Optical properties, High resolution XRD

  • F. S. Hashem :
    Removal of methylene blue by magnetitecovered bentonite nano-composite524-529en [619.61 kB - PDF]EPA-02286-00018-0090

    Batch adsorption experiments were carried out for the removal of methylene blue from aqueous solutions using Fe3O4/bentonite nanocomposite. Effects of the contact time, mass of the adsorbent and the pH of the initial dye solution on the adsorption capacity were studied. The results showed that the adsorption capacity for the dye increased by increasing the contact time and initial pH of the solution. However, it decreased with increasing the adsorbent. The adsorption kinetics was in good agreement with pseudo 2nd order kinetic equation and the intra-particle diffusion model. The adsorption isotherm showed good fitting to Langmuir equation and the maximum adsorption capacity was1600 mg/g. For this the prepared nano-composite could be regarded as a potential adsorbent for MB removal in a wastewater treatment.

    Keywords: magnetite, bentonite, nano-composite, methylene blue

  • T. Y. Soror :

    To verify the relationship between the properties of composite coatings prepared on steel and the SiC content of electroless Ni-P-SiC composite coatings. Systematic experiments have been conducted to study the possibility of incorporating solid SiC particles in Ni-P matrix. Kinetics of Ni-P plating reveal that the rate of deposition was found to increase linearly with time. The reduction process of nickel ions by hypophosphite was completely hindered at pH less than 2 and the minimum temperature at which the bath can be practically operated was about 65 °C. The mode of deposition of Ni-P film has been explored in the light of deposition condition. XRD analysis of the as- plated and heat – treated samples revealed the existence of crystalline Ni3P phases for the heat – treated alloy. Finally a component electroless Ni-PSiC composite plating process producing a high wear resistance of the coating.

    Keywords: Ni-P plating solution; SiC particles; composite coatings; steel; heat treatment

Industrial and engineering chemistry

  • Sanjay Prasad Gupta :

    Climate is the act of all atmospheric events such as rainfall, temperature, wind, air pressure and humidity etc. In recent years, the alterations about natural environment and climate observed in Chhattisgarh state negatively affected the monumental buildings, the cultural riches of the state that they have been worn out by various natural effects for a long time. However, since monumental buildings have great importance due to their identity of transferring old era information to the future generations, there should be taken special precautions against deteriorations on the monumental buildings. Climate-related deteriorations on the monumental buildings resulted from temperature differences between summer-winter and day-night, water movement at the building due to capillarity, abrasive effects of rain water, salt and some chemicals involved in water, particles carried by wind and air pollution. The deteriorations occurred on the monumental buildings due to climate changes have investigated for Chhatisgarh and the deterioration effects on construction materials have been discussed.

    Keywords: Monument, Climate, Climate Impacts, Historical Buildings, Deterioration