Open Access Original Research Article

One-pot Synthesis of 1H-benzo[f]chromen-2-yl (phenyl)methanone Derivatives in the Presence of Copper Triflate as Catalyst Using Ultrasonic Irradiation

Tamrat Yimenu Zeleke, Kadir Turhan, Zuhal Turgut

Chemical Science International Journal, Page 1-8
DOI: 10.9734/ACSJ/2016/24655

A rapid, efficient and environment-friendly protocol for the synthesis of naphthopyranes has been developed by one-pot condensation of 2-naphthol, various aromatic aldehydes and benzoylacetone or 1,3-diphenyl-1,3-propandione in the presence of Cu(OTf)2 as catalyst under ultrasonic irradiation. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, high yield and economic availability of the catalyst.

Open Access Original Research Article

Single Crystal XRD, Bioevaluation and DFT Analysis of 4-Phenylsulfanylbutyric Acid (4PSBA) and Its Cocrystal with 2-Amino-5-nitropyridine (2A5NP)

V. Velmurugan, P. Palanisamy, R. Subramanian, N. Bhuvanesh, S. Gomathi, P. Thomas Muthiah, B. Ravindran Durai Nayagam, S. Kumaresan

Chemical Science International Journal, Page 1-16
DOI: 10.9734/ACSJ/2016/25166

The crystal structures of 4-phenylsulfanylbutyric acid (4PSBA) and its cocrystal with 2-amino-5-nitropyridine (2A5NP) have been studied. Both 4PSBA and its co-crystal, 4PSBA:2A5NP belong to the triclinic crystallographic system with the same space group P-1. Theoretical energy calculations indicated the high energy of the formers 4PSBA and 2A5NP than the cocrystal (4PSBA:2A5NP). The cocrystal has the lowest energy gap (ΔE, 2.9709 eV), lowest hardness (1.4854 eV), highest softness (0.6732 eV), and the highest electrophilicity (5.7412 eV). The cocrystal shows better antimicrobial- and DNA cleaving activity than the acid (4PSBA).

Open Access Original Research Article

Stagnation Point Flow of a Williamson Fluid over a Nonlinearly Stretching Sheet with Thermal Radiation

M. Monica, J. Sucharitha, Ch. Kishore Kumar

Chemical Science International Journal, Page 1-8
DOI: 10.9734/ACSJ/2016/25144

The present analysis deals with the study of stagnation point flow of a Williamson fluid over a nonlinearly stretching sheet with thermal radiation. The partial differential equations governing this phenomenon were transformed into coupled nonlinear ordinary differential equations with suitable similarity transformations. These equations were then solved by numerical technique known as Keller Box method. The various parameters such as Prandtl number (Pr), velocity ratio parameter(), Williamson parameter (λ) and Radiation parameter (R) and non linear stretching parameter (n) determining the velocity and temperature distributions, the local Skin friction coefficient and the local Nusselt number governing such a flow were also analyzed. On analysis it was found that the Williamson fluid parameter (λ) decreased both the fluid velocity whereas an increase in (λ) increased wall skin-friction coefficient. The wall temperature gradient increased with an increase in Pr but decreased with radiation parameter R.

Open Access Original Research Article

Chemical Constituents and Antimicrobial Activity of the Leaf Essential Oil of Garcinia kola Heckel (Clusiaceae) from Nigeria

Samuel Ehiabhi Okhale, Chukkol Ismail Buba, Peters Oladosu, Henry O. Egharevba, Grace Ugbabe, Jemilat A. Ibrahim, Oluyemisi Folashade Kunle

Chemical Science International Journal, Page 1-7
DOI: 10.9734/ACSJ/2016/24019

All parts of Garcinia kola are used in traditional medicine for various ailments including inflammation and infections. The leaf essential oil (EO) of Garcinia kola was isolated by hydrodistillation using Clavenger type apparatus and subjected to GC-MS analyses. A total of twenty-seven compounds were identified representing 88.27% of the oil. The main components of the essential oil were citronellic acid (48.3%), 5,9-undecadien-2-one (5.12%), α-ionone (4.38%),  3-buten-2-one (3.25%), 2-pentadecanone (2.59%), squalene (2.27%), nonacosane (2.18%), octanal (1.9%), geraniol (1.52%), mesitylene (1.17%) and α-farnesene (1.02%). The oil contained many compounds that were active against Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli, Candida albicans and Mycobacterium bovis with minimum inhibitory concentrations ranging from >400 to 50 μg/ml and could be exploited for the development of plant-based drugs.



Open Access Original Research Article

Adsorption, Thermodynamics and Kinetics of Methylene Blue on Nano Structured ZnO Crystals

Ismail K. Al-Khateeb, Muna S. Mahmood

Chemical Science International Journal, Page 1-9
DOI: 10.9734/ACSJ/2016/25000

This investigation was concern to study the removal of methylene blue pollutants from aqueous solution using nano ZnO synthesized from raw materials of zinc oxide. The equilibrium adsorption data were analyzed using adsorption models of Langmuir, Freundlich and Temkin. The thermodynamic and kinetics parameters were calculated using adsorption process on nano ZnO for the methylene blue solution at different temperatures. It was found that a ZnO at nano level has a very significant adsorption for methylene blue compared to that of raw materials. The results showed that the model isotherms are fitting very well with the experimental data. The specific adsorption percentage of methylene blue was highly affected by addition of nano ZnO and decreasing with temperature compared to that of control sample. It has been found that the adsorption capacity was increased by increasing the methylene blue concentrations, and these values indicated that the methylene blue adsorption onto nano ZnO was spontaneous and endothermic in nature. All values of Gibbs functions were negative with values of -15 and -17 kJmol-1 for temperatures of 293 to 323K, while values of enthalpy and entropy about -33 kJmol-1 and 72 JK-1 mol-1 for nano ZnO respectively. These results indicated that the adsorption process was feasible, spontaneous and exothermic. Kinetic Study showed that the value of the rate constant is 0.338 min-1.

Open Access Original Research Article

A Theoretical Study of the Enol Contents of Cyclohexanone, Cyclopentanone and Acetone

Ghassab M. Al-Mazaideh, Salim M. Khalil

Chemical Science International Journal, Page 1-8
DOI: 10.9734/ACSJ/2016/25048

PM3 and DFT calculations have been performed with complete optimization of geometries on cyclohexanone, cyclopentanone, and acetone. The enol content trend determined in this work was cyclohexanone > cyclopentanone > acetone, which was found to agree with published experimental and theoretical works. Equilibrium constants, strain energies of enols, and electron distributions are reported.