A novel series of compounds were synthesized by condensation reaction of substituted acetophenone (1a-b) with substituted aldehyde (2a-b) in presence of alcoholic sodium hydroxide to get intermediate chalcones (3a-c), which were further treated with hydroxylamine hydrochloride in presence of sodium hydroxide to get isoxazolines derivatives (4a-c). The latter were refluxed with substituted primary amines and formaldehyde for 6-10 h to afford Mannich bases. The synthesized compounds were characterized on the basis of their spectral (IR, 1HNMR) data and evaluated for the antimicrobial activity by using Zone of Inhibition by cup plate method and Minimum Inhibitory Concentration by broth dilution method.
Bismuth basic nitrate (BBN) and its TiO 2 -Ag modified sorbent, PTBA were successfully synthesized via a precipitation method. The structural characteristics of prepared sorbents were determined through different analytical techniques. The potential use of prepared sorbents for organic compounds' removal was evaluated using Methyl Orange and Sunset Yellow dyes as model pollutants in aqueous solutions. The experimental results showed that the presence of TiO 2 and Ag particles during the crystal growth of bismuth basic nitrate has an effect on the crystal structure, point of zero charge (pHpzc), pore volume and diameter. The lower binding energy of Ti 2p core level peak indicates the octahedral coordination of TiO 2 particles on the PTBA surface. The alteration of hydrophilic-hydrophobic characteristics of sorbent's surface improves the adsorptive performance of the modified sorbent and provides an efficient route for organic contaminants' removal from aqueous solutions.
In the present investigation we have synthesized a series of new 1‐[3‐(4‐substitutedphenyl)‐5‐phenyl‐4H‐1,2,4‐triazol‐4‐yl]urea and 1‐[3‐(4‐substitutedphenyl)‐5‐phenyl‐4H‐1,2,4‐triazol‐4‐yl]thiourea derivatives (4Ia ‐ 4IId). The newly synthesised derivatives were characterized by using the data of IR, 1 H NMR and Mass Spectral analysis. Thus synthesised and characterized targetted compounds were further screened for their anti‐inflammatory activity by using Carrageenan – induced paw edema rat model. Among all the newly synthesized derivatives, Compounds 4Ia‐4Ic and Compounds 4IIa‐4IId were reduced the inflammation very significantly (p<0.0001), thus these compounds showed promising anti‐inflammatory activity and only one compound (4Id) showed moderate anti‐inflammatory activity (p<0.05).
A new spectrophotometric method was developed for the simultaneous analysis of a ternary mixture containing paracetamol (PAR), ibuprofen (IBU) and caffeine (CAF) without prior separation. H-point standard addition method (HPSAM) was used for the first time in the analysis of a component (IBU) in a ternary mixture (paracetamol, ibuprofen and caffeine). In contrast, PAR and CAF determined using double divisor ratio spectra derivative method. This method is based on the use of derivative of the ratio spectrum obtained by dividing the absorption spectrum of the ternary mixture by a standard spectrum of a mixture of two of the three compounds in the title mixture. The concentrations of PAR and CAF compounds in their mixture are determined by using their respective standard addition graphs which are obtained by measuring the amplitude at either the maximum or minimum wavelengths selected. The mathematical explanation of the procedure is illustrated. It was shown that at wavelengths 226 and 260 nm, the coordinate of H-point is only dependent on the concentration of IBU without any interference by PAR and CAF. This method was successfully applied for the analysis of Novafen capsule, with no interference from excipients as indicated by the recovery study results. The proposed method is simple and rapid and can be easily used in the quality control of drugs as an alternative analysis tools.
A new, simple and sensitive spectrophotometric method in ultraviolet region has been developed for the determination of Bosentan in bulk and in pharmaceutical formulations. Bosentan exhibits absorption maxima at 273 nm with apparent molar absorptivity of 1.3293×10 4 L/mol.cm in methanol and octane 1-sulfonic acid solvent mixture. Beer's law was found to be obeyed in the concentration range of 0.1-100 μg/mL. The method was validated as per the ICH guidelines.
The inhibition effect of morpholine on the corrosion of mild steel in 2N sulphuric acid and phosphoric acid has been studied by mass loss and polarization techniques between 302K and 333K. The inhibition efficiency increased with increase in concentration. The corrosion rate increased with increase in temperature and decreased with increase in concentration of inhibitor compared to blank. The adsorption of inhibitor on the mild steel surface has been found to obey Temkin's adsorption isotherm. Potentiostatic polarization results reveal that morpholine act as mixed type inhibitor. The values of activation energy (Ea), free energy of adsorption (∆Gads), enthalpy of adsorption (∆H), and entropy of adsorption (∆S) were also calculated.
The high-resolution Fourier transform infrared spectrum of nitrogen trifluoride NF3 has been studied in the v1 + v4 perpendicular band region around 1523 cm−1. All experimental data have been refined applying various reduction forms of the effective rovibrational Hamiltonian developed for an isolated degenerate state of a symmetric top molecule. The v1 = v4 = 1 excited state of the 14NF3 oblate molecule was treated with models taking into account ℓ- and k-type intravibrational resonances. Parameters up to sixth order have been accurately determined and the unitary equivalence of the derived parameter sets in different reductions was demonstrated.
This study is carried out for the removal of cobalt from aqueous solution using granular activated carbon in combination with p-nitro benzoic acid at temperature 25±1 °C. The adsorption isotherm of cobalt on granular activated carbon has been determined and the data fitted reasonably well to the Langmuir and Freundlich isotherm for activated carbon.
The Series of N-(5-(Substituted phenyl)-4,5-dihydro-1H-pyrazol-3-yl)-4H-1,2,4-triazol-4-amine compounds were prepared by reaction of 4-amino-1,2,4-Triazole with Acetyl Chloride followed by different aromatic aldehydes and cyclization with hydrazine hydrate. The structures of new compounds were confirmed by IR and 1H-NMR spectral data. Anti-bacterial and Anti-fungal activities were evaluated and compared with the standard drugs, some compounds of the series exhibited promising anti-microbial and anti-fungal activity compared to standard drugs.
Highly efficient method for the preparation of N-tert-butyl amides by reaction of nitriles with tert-butyl acetate is described using polyvinylpolypyrrolidone-supported boron trifluoride (PVPP-BF3) at 70 degrees C in good to excellent yields. Selective amidation of benzonitrile in the presence of acetonitrile was also achieved. polyvinylpolypyrrolidone-boron trifluoride complex shows non-corrosive and stable solid catalyst elevated Lewis acid property.
A series of oxazole and thereof imidazole derivatives were prepared from 2-chloro-7-methyl-3-formyl quinoline. The structures of all synthesized compounds were elucidated by elemental, IR, 1 HNMR, 13 CNMR spectra. Supplementary to these, they were assayed in vitro for their antimicrobial activity; it was revealed that some synthesized derivatives were exhibiting competent biological activity against both gram negative and gram positive bacterial species and fungal microorganisms.
Activated carbon monoliths disc and honeycomb type were prepared by chemical activation of coconut shell with zinc chloride at different concentrations, without using a binder. The structures were characterized by N-2 adsorption at 77 K and immersion calorimetry into benzene. The experimental results showed that the activation with zinc chloride produces a wide microporous development, with micropore volume between 0,38 and 0,79 cm(3)g(-1), apparent BET surface area between 725 and 1523 m(2)g(-1) and immersion enthalpy between 73,5 and 164,2 Jg(-1). We compared the experimental enthalpy with calculated enthalpy by equation Stoeckli-Kraehenbuehl finding a data dispersion from which can infer that the structures are not purely microporous; this fact is ratified with similar behavior that the evidence t the product EoWo.
Terpolymeric resin was prepared from m-cresol (0.1M), hexamine (0.05M) and formaldehyde (0.2M) by acid catalyzed polycondensation method using 1M HCl in temperature range of 122-130°C.The resin was abbreviated as m-CHF-I. The molecular weight of terpolymer was determined by non-aqueous conductometric titration technique. The structure of resin was determined by its elemental analysis, UV-VIS, IR, and NMR data. The thermokinetic parameters were determined using Freeman-Carroll (FC) and Sharp Wentworth (SW) method in temperature range (410-485°C).The values of activation energies (Ea), entropy (∆S), and free energies (∆G) were in good agreement . The order of degradation reaction determined by FC method was confirmed by SW method.
Activated carbon obtained from orange peel (ACOP) was synthesized and used for the removal of heavy metal ions (Cr, Cd, and Co) from aqueous solutions. Two different adsorption models were used for analyzing data. Adsorption capacities were determined: copper ions exhibit the greatest adsorption on activated carbon orange peel because of its size and pH conditions. Adsorption capacity varies as a function of pH. Adsorption isotherms from aqueous solution of heavy metals on ACOP were determined. Adsorption isotherms are consistent with Langmuir's adsorption model. Adsorbent quantity and immersion enthalpy were studied.
2,3-Dihydro-1H-1,5-benzodiazepines were synthesized by reaction of o-phenylenediamine with ketones (acyclic / cyclic) under solvent free conditions in the presence of tetra butyl ammonium bromide (TBAB) in short reaction time with excellent yield.
A new medium, eggshell powder has been developed for fluoride removal from aqueous solution. Fluoride adsorption was studied in a batch system where adsorption was found to be pH dependent with maximum removal efficiency at 6.0. The experimental data was more satisfactorily fitted with Langmuir isotherm model. The kinetics and the factor controlling adsorption process fully accepted by pseudo-second-order model were also discussed. Ea was found to be 45.98 kJmol-1 by using Arrhenius equation, indicating chemisorption nature of fluoride onto eggshell powder. Thermodynamic study showed spontaneous nature and feasibility of the adsorption process with negative enthalpy (∆H0) value also supported the exothermic nature. Batch experiments were performed to study the applicability of the adsorbent by using fluoride contaminated water collected from affected areas. These results indicate that eggshell powder can be used as an effective, low-cost adsorbent to remove fluoride from aqueous solution as well as groundwater.
2-Substituted benzimidazoles have been synthesized in a one-pot reaction from o-phenylenediamine and aldehydes in the presence of boric acid in water at room temperature. The method was proved to be eco-friendly, convenient and the products were isolated with good yields.
A series of the Schiff’s bases incorporating coumarin and chalcone moeities, 3-(4-(4-(substituted phenyl)prop-1-ene-3-one) phenylimino) methyl)-4-chloro-2h-chromen-2-one 4(a-g) were synthesized as potential antimicrobial agents. These compounds were characterized on the basis of their spectral (IR, 1H NMR) data and evaluated for antimicrobial activity in vitro against gram positive and gram negative bacteria and fungi. Compound 4b was found to be most active with an MIC of 20 µg/mL against all the tested organisms.
Leachate from mature landfills is typically characterized by high ammonium (NH4+) content, low biodegradability (low BOD5/COD ratio) and high fraction of refractory and large organic molecules such as humic and fulvic acids. Mature leachate effluents are known to contain recalcitrant and/or non-biodegradable organic substances and biological processes are not efficient in these cases. A promising alternative to complete oxidation of biorecalcitrant leachate is the use of ultrasonic process as pre-treatment to convert initially biorecalcitrant compounds to more readily biodegradable intermediates, followed by biological oxidation of these intermediates to biomass and water. The objectives of this study are to investigate the effect of son catalysts process on biodegradability improvement. Results showed that when applied as relatively brief pre-treatment systems, the sonocatalysis processes induce several modifications of the matrix, which results in significant enhancement of its biodegradability. For this reason, the integrated chemical-biological systems proposed here represent a suitable solution for the treatment of landfill leachate samples with an efficient remediation of the relevant parameters (COD, TOC).
