Vol 4, No 4 (2013)

December 2013

Table of Contents


Hakan Arslan
DOI 10.5155/eurjchem.4.4.i-i.944
Editorial Board
Hakan Arslan
DOI 10.5155/eurjchem.4.4.ii-vii.945
Graphical Contents

Research Article

Batthini Guruswamy, Rama Krishnan Arul, Muggu Venkata Satya Rama Krishna Chaitan, Sai Subrahmanya Praveen Kumar Darsi
DOI 10.5155/eurjchem.4.4.329-335.792

Synthesis of new β-hydroxy benzimidazolyl sulfides (4a-e) and β-hydroxy benzimidazolyl sulfones (5a-e) containing 7-piperazine fluoroquinolones have been described and evaluated for their antimicrobial activity. Benzoxazine fluoroquinolone carboxylic acid, 1, on reaction with piperazine in presence of triethylamine in acetonitrile under reflux resulted 7-piperazine bezoxazole fluoroquinolone, 2. The latter is reacted with epichlorohydrine in presence of NaOH in acetone yielded corresponding N-substituted epoxide, 3, with retained chirality, which on treatment with 5-substituted-2-mercaptobenzimidazoles given the corresponding β-hydroxy bezimidazolyl sulfides (4a-e). Further compounds 4a-e on treatment with H2O2 and ammonium molybdate in dichloromethane yielded the β-hydroxy bezimidazolyl sulfones, 5a-e. The antimicrobial activity of newly synthesized compounds along with levofloxacin (reference drug) were evaluated against different microorganisms and found many of the evaluated compounds have been exhibited remarkable activity.

Dmitry Murzin, Vera Kolesova
DOI 10.5155/eurjchem.4.4.336-342.828

A variety of 2-(N-alkoxy(thio)carbonyl alkyl(aryl)amino)-1,3,2-dioxaphospholanes and phosphorinanes were prepared from chlorodioxaphospholanes and phosphorinanes. Their structures were determined by IR, Mass and NMR spectroscopy. These compounds were employed in direct reactions with elemental sulphur and methylester of chloroacetic acid giving potentially physiologically active N-phosphorylated carbamates with P(O)-N and P(S)N bonds.

Jan Kurjata, Krystyna Rozga-Wijas, Wlodzimierz Stanczyk
DOI 10.5155/eurjchem.4.4.343-349.835

An effective synthesis of methylethoxysilanes and emulsification of methyltriethoxysilane is described. Hydrolysis and condensation products of methyltriethoxysilane were identified and studied using 29Si NMR, mass spectrometry and infrared spectroscopy. The presented analyses are important from practical point of view, as the emulsion in question is used for hydrophobization of building materials and soil. The most striking finding is high stability of the low molecular products of hydrolysis - methylsilanetriol [MeSi(OH)3] and its dimer [(OH)2(Me)SiOSi(Me)(OH)2]. All of which were still present in the aqueous medium, after 40 days of storage at ambient conditions. This finding suggests that condensation processes leading to the formation of polymer network are slow in the emulsion and a large number of reactive hydroxyl groups are present in the system allowing for the effective hydrophobization of mineral material.

Masaki Ichitani, Soh-ichi Kitoh, Keiko Tanaka, Shuhei Fujinami, Mitsuhiro Suda, Mitsunori Honda, Akio Kuwae, Kazuhiko Hanai, Ko-Ki Kunimoto
DOI 10.5155/eurjchem.4.4.350-352.872

(S)-5-Isopropyl-5-methyl-2-thiohydantoin was synthesized by one-pot reaction of α-methyl-L-valine and thiourea in the absence of solvent. The crystal structure of this compound has been determined from single crystal X-ray diffraction data. This is the first report on the crystal structure of a homochiral 5-substituted 2-thiohydantoin with the unsubstituted NH groups. This compound, C7H12N2OS crystallizes in the chiral orthorhombic space group P212121 with four molecules in the unit cell. The unit cell parameters are: a = 8.2798(12) Å, b = 8.6024(13) Å, c = 12.826(2) Å and V = 913.6(2) Å3. In the crystals, the thioamide and amide N-H of one molecule are hydrogen-bonded to the thioamide C=S group of neighboring molecules to form rings with the R22(8) graph-set motif, and these rings are linked into infinite one-dimensional tapes.

Abdulkadir Mohammed Noori Jassim, Fatin Fadhel Mohammed Al-Kazaz
DOI 10.5155/eurjchem.4.4.353-359.853

Noble metal nanoparticles were synthesized directly by pulsed laser ablation (Nd:YAG, λ=1064 nm) of gold and silver plates immersed in pure water. Concentrations of the nanoparticles were determined by atomic absorption spectroscopy measurement. Atomic force microscope and transmission electron microscope analysis were used to characterize the size and size distributions of the metals nanoparticles. The objective of this work is studying the effects of presence gold and silver nanoparticles on the levels of tri-iodothyronine hormone (T3) in saliva of patients with chronic renal failure their thyroid had disorder (hypothyroidism). Also the study characterized the binding between the anti-T3antibody with its antigen i.e., T3 in saliva patients in the presence affixed size concentration of nanoparticles to improve and modify a competitive ELISA method. It is found that both gold and silver nanoparticles demonstrated activation effect on the binding between anti-T3 antibody and antigen (T3) in the saliva of patients and these effects increased with increasing the concentrations and size for both nanoparticles (gold was more activation effect than silver). Optimization of experimental conditions for the binding in the saliva were: 40 μL and 20 μL of saliva (T3) in presence both silver and gold nanoparticle, respectively, pH = 7.4 of 0.2 M phosphate buffer was selected as the detection solution, the temperature of incubation was 22 °C while the incubation time were 30 min, 90 min for silver and gold nanoparticles, respectively.

Ramzia Ismail El-Bagary, Ehab Farouk Elkady, Bassam Mahfouz Ayoub
DOI 10.5155/eurjchem.4.4.360-365.843

In this work, the acidic degradation product of sitagliptin phosphate monohydrate (STG) was synthesized, separated and its structure was elucidated. Additionally, two reversed-phase liquid chromatographic (RP-LC) methods have been developed for the determination of STG. The first method comprised the determination of STG in binary mixture with sitagliptin acid degradation product (SDP) in laboratory prepared mixtures, in plasma and in dosage form. This method was based on isocratic elution using a mobile phase consisting of potassium dihydrogen phosphate buffer (pH =4.6) - acetonitrile (30:70, v:v) with fluorometric detection. The fluorometric detector was operated at 267 nm for excitation and 575 nm for emission. In the second method, the simultaneous determination of STG and metformin (MET) in the presence of SDP has been developed. In this method, the ternary mixture of STG, MET and SDP was separated using a mobile phase consisting of potassium dihydrogen phosphate buffer (pH = 4.6) - acetonitrile (15:85, v:v) with UV detection at 220 nm. Chromatographic separation in the two methods was achieved on a Symmetry® Waters C18 column (150 mm × 4.6 mm, 5 μm). The optimized methods were validated and proved to be specific, robust and accurate for the quality control of the cited drugs in pharmaceutical preparations.

Cristina Volzone, Norma Gallegos, Carlos Cantera, Alberto Greco
DOI 10.5155/eurjchem.4.4.366-369.862

Two clays rich in montmorillonite were modified and used as adsorbents. The clay minerals were modified with hexadecylpyridinium cation (HDP+) in order to obtain organo-montmorillonites, which were used for retaining acid black 210 dye from water solution. This dye is frequently used in tanning industry. The retentions of the anionic dye by organo-montmorillonites were evaluated by using complete UV-visible spectrum, analyzing the concentrations of dye solutions before (50 mg/L) and after the contact with the adsorbent. The solids were characterized by X-ray diffraction (XRD) and infrared analyses (FT-IR). The interlayer spacing of the montmorillonites increased, after organic cation exchange, from 13.0-14.9 Å to 19.0-22.0 Å and allowed the uptake of acid black 210 dye. The most disordered arrangement of HDP in montmorillonite, deduced by XRD and FT-IR analyses, was better for higher retentions of acid black dye.

Mutlaq Shedeed Aljahdali, Ahmed Abdou El-Sherif, Rifaat Hasan Hilal, Abeer Taha Abdel-Karim
DOI 10.5155/eurjchem.4.4.370-378.803

Mixed ligand complexes of M(II) {M = Cu(II), Ni(II), Co(II) and Zn(II)} with 1,10-phenanthroline (1,10-Phen) and Schiff base namely 2-aminomethylthiophenyl-4-bromosalicylaldehyde (ATS) have been synthesized. These metal chelates have been characterized by elemental analyses, IR, 1H NMR, solid reflectance, magnetic moment and molar conductance. Spectral data showed that the 1,10-phenanthroline act as neutral bidentate ligand coordinating to the metal ion through two nitrogen donor atoms and Schiff base (ATS) acts as monobasic bidentate coordinating through through azomethine-N and phenolic-oxygen groups. The geometry of the studied M(II) complexes has been fully optimized. The metal chelates have been screened for their antimicrobial activities using the disc diffusion method against different selected types of bacteria and fungi. In vitro antitumor activity assayed against two human cell lines colon (HCT116) and larynx (HEP2) cancer cells. Solution equilibrium studies were also investigated.

Azza Abdelwahab Shoukry
DOI 10.5155/eurjchem.4.4.379-387.868

Imipenem is one of the β-lactam antibiotics (β-lactamase inhibitors), which are reported to be the most important class of drugs that are capable of inhibiting the bacterial enzyme to protect the β-lactam antibiotic from destruction. In view of the biological importance of imipenem as drug, the ligation behavior of imipenem is studied in order to get an idea about its potentiality towards some transition metals in in-vitro systems. The binary complex formation equilibria with the metal ions Cu(II), Ni(II), Co(II), Mn(II), and Zn(II) were investigated potentiometrically. The effects of dioxane as a solvent, on the protonation constant of imipenem and the formation constants of Cu(II)-imipenem complexes were discussed. The ternary copper(II) complexes involving imipenem and various biologically relevant ligands containing different functional groups, as amino acids, amides, dicarboxylic acids and DNA constituents were investigated. The stability constants of the complexes are determined. The mechanisms of complex formation are speculatively discussed based on the calculated stability constant values. The ternary complexes are formed by simultaneous reactions. The concentration distributions of various species formed in solution were also evaluated as a function of pH.

Asima Siddiqa, Sumbul Sabir, Syed Tajammul Hussain, Bakhtiar Muhammad
DOI 10.5155/eurjchem.4.4.388-395.826

Titania-silica nanocomposites (20% SiO2-TiO2, 30% SiO2-TiO2, 40% SiO2-TiO2 and 50 % SiO2-TiO2) with tailored morphology and tunable band energy have been synthesized successfully via micro emulsion method. The morphology, chemical composition, band gap energy and stability of prepared nanocomposites were investigated by XRD, SEM/EDX, FT-IR, DRS and TGA. While textural parameters such as surface area, pore volume, and pore diameter were evaluated by nitrogen adsorption-desorption isotherms. The prepared nanocomposites were employed for photocatalytic degradation of phenol and dyes (methyl yellow, auramine O, turquoise blue G) under visible light irradiations. The results of photocatalytic degradation and kinetic parameter (Kapp) strongly suggest that 20% SiO2-TiO2 showed remarkable photocatalytic efficiency in comparison to SiO2-TiO2 nanocomposites with high silica contents. These findings proved significantly that 20% SiO2-TiO2 have marked impact on the photocatalytic efficiency due to its high pore volume, more diameter, high availability of anatase TiO2 in nanocomposite and reduced bandgap energy.

Bharat Kumar Bugata, Satya Venkata Gopala Krishna Kaladhar Dowluru, Vasudeva Rao Avupati, Venkateswara Rao Gavalapu, Divakara Laxman Somayajulu Nori, Sreenu Barla
DOI 10.5155/eurjchem.4.4.396-401.878

A series of some new diarylsulfonylurea-chalcone hybrids (4a-4y) have been synthesized via Claisen-Schmidt condensation reaction by treating 1-(3-acetylphenyl)-3-tosylurea with various aromatic/heteroaromatic aldehydes in the presence of alkali and characterized by FT-IR, 1H NMR, 13C NMR and LC mass spectral analysis. All the synthesized compounds were evaluated for their in vitro 5-Lipoxygenase inhibitory activity using potato 5-lipoxygenase enzyme. Among the tested compounds 4r and 4o exhibited significant inhibitory activity at IC50 values 7.88±0.14 and 11.77±0.21 µg/mL, respectively. This level of activity was found comparable to that of the reference drug Abietic acid (LI01020) with IC50 value 4.34±0.37 µg/mL and it could be a remarkable starting point to develop new lead molecules.

Chalya Mallappaji Shivaprasad, Swamy Jagadish, Toreshettahally Ramesh Swaroop, Chakrabhavi Dhananjaya Mohan, Rangaswamy Roopashree, Kothanahally Shivaramu Sharath Kumar, Kanchugarakoppal Subbegowda Rangappa
DOI 10.5155/eurjchem.4.4.402-407.864

A series of piperidine conjugated benzisoxazole derivatives were synthesized and evaluated for their antibacterial, anti-oxidant and anti-inflammatory activities. The results showed that most of the tested compounds exhibit good to moderate antimicrobial activity against some strains of Gram negative bacteria (Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Shigella flexineri) and Gram positive bacteria (Bacillus subtilis). Further, the molecules were evaluated for anti-oxidant assays such as DPPH scavenging, super oxide radical scavenging and hydroxyl radical scavenging assays. Most of the compounds showed potent antioxidant activities. Also, the synthesized compounds were screened for anti-inflammatory activities such as lipoxygenase inhibition and indirect haemolytic assays, where compounds revealed good activity.

Jayachamarajapura Pranesh Shubha, Kotabagi Vinutha, Puttaswamy Puttaswamy
DOI 10.5155/eurjchem.4.4.408-413.806

The kinetics of oxidative decolorization of amido black (AB, Naphthol blue black) by chloramine-T (CAT) and bromamine-T (BAT) in acidic medium has been investigated spectrophotometrically (λmax = 618 nm) at 298 K. Kinetic runs were performed under pseudo first-order conditions of [Oxidant]o >> [AB]o. Under identical experimental conditions, reactions with both the oxidants follow identical kinetics with a first-order dependence on each [Oxidant]o and [AB] and a fractional-order dependence on [HClO4]. Stoichiometry of the reaction was found to be 1:4 and the oxidation products were identified. The reaction was studied at different temperatures and various activation parameters have been computed. Effects of p-toluenesulfonamide, halide ions, ionic strength and dielectric constant of the medium have been investigated. Reaction mixture fails to induce polymerization of acrylonitrile. The rate of oxidation of AB is about three-fold faster with BAT as compared to CAT. This may be attributed to the difference in electrophilicity of Cl+ and Br+ ions and also the Vander Waals radii of chlorine and bromine. Plausible mechanism and related rate law have been deliberated for the observed kinetics.

Hayam Mahmoud Lotfy, Maha Abdel Monem Hegazy, Sherif Abdel Naby Abdel-Gawad
DOI 10.5155/eurjchem.4.4.414-421.829

Five simple, sensitive and precise spectrophotometric and chemometric methods were used for simultaneous determination of Simvastatin (SM) and Sitagliptin (SIT) in their pure powdered forms and in the tablets. The proposed methods are the extended ratio subtraction method (EXRSM), ratio difference method (RDSM), mean centering of ratio spectra method (MCR) and chemometric methods, namely principal component regression (PCR) and partial least squares (PLS). In EXRSM; SM was determined at 237.5 nm, while SIT was determined at 267 nm, in RDSM; the difference in amplitudes at 237.5 and 245.5 nm was used for SM and 263.5 and 248.0 nm for SIT, while in MCR; SM and SIT were determined at 239.0 and 273.0 nm, respectively. PCR and PLS are factor based multivariate methods which utilize the whole spectra of SM and SIT. The developed methods were successfully applied for the determination of the studied drugs in their bulk powder, laboratory prepared mixtures and in tablets. All validation parameters of the developed methods were determined. The obtained results were statistically compared with each other along with a reported method.

Gangadhar Asaram Meshram, Shruti Shashank Deshpande, Vipul Amratlal Vala, Pramod Arun Wagh
DOI 10.5155/eurjchem.4.4.422-424.857

An efficient method for synthesis of quinoxalines and substituted pyrido-pyrazines has been developed from different 1,2-dicarbonyl compounds and substituted 1,2-diamines using Indion 190 resin as a solid acid catalyst. Ambient reaction conditions, high product yield and reusability of the catalyst with minimal loading are the salient features of the present protocol.

Hassan Hasan Hammud, Mayssam Mostafa Chahine, Bassem El-Hamaoui, Younes Hanifehpour
DOI 10.5155/eurjchem.4.4.425-433.776

Silica-carbon nanoparticles (SCNP) were prepared from sonication of silica and anthracene. The size of homogenous nanoparticle is around 5-20 nm confirmed by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). SEM analysis indicated surface porosity. SCNP were used to remove lead ions (Pb(II)) from aqueous solutions. Adsorption isotherm of Pb(II) on SCNP was well fitted in terms of the Freundlich and Langmuir models. The maximum adsorption capacity of SCNP for Pb(II) was found to be 385 mg/g (1.86 mmol/g) in batch experiment. Thermodynamic studies indicated that sorption process of lead onto SCNP was spontaneous and exothermic. A pseudo-second order model has been employed in order to describe the kinetic adsorption processes, and the thermodynamic activation parameters were calculated. In a column studies, qy the Yan adsorption capacity of SCNP for Pb(II) was found to be 130.66 mg/g (0.63 mmol/g).

Mutlaq Shedeed Aljahdali
DOI 10.5155/eurjchem.4.4.434-443.838

A series of novel thiosemicarbazone compounds, HL1, 2-(1-(2-phenyl-hydrazono)-propan-2-ylidene)hydrazine-carbothioamide (TPHP), HL2, N-methyl-2-(1-(2-phenyl-hydrazono)-propan-2-ylidene)hydrazinecarbothioamide (MTPHP) and, HL3, N-phenyl-2-(1-(2-phenyl-hydrazono)-propan-2-ylidene)hydrazinecarbothioamide (PTPHP) and their Ni(II) complexes have been synthesized and characterized using elemental analysis, magnetic susceptibility, molar conductance and spectral measurements. IR spectra indicate that the free ligands exist in the thione form rather than thiol form in the solid state. In all the studied complexes, all ligands behave as a tridenate anion with coordination involving the two azomethine nitrogens and the thiolate sulfur after deprotonation. The magnetic and spectral data indicates a square planar geometry for Ni(II) complexes. The structures of the free thiosemicarbazone ligands and their Ni(II) complexes have been modelled using parameterized PM3 semiempirical method. The free ligands and their Ni(II) chelates have been screened for their antimicrobial activities.

Ramzia Ismail El-Bagary, Ehab Farouk Elkady, Bassam Mahfouz Ayoub
DOI 10.5155/eurjchem.4.4.444-449.844

A simple and precise liquid chromatographic method has been developed and validated for the determination of either sitagliptin (STG), vildagliptin (VLG) or saxagliptin HCL (SXG) and metformin HCL (MET) in the presence of metformin degradation product, 1-cyanoguanidine (CGN). Chromatographic separation was achieved on a Symmetry® cyanide column (150 mm × 4.6 mm, 5 μm). Isocratic elution using a mobile phase of potassium dihydrogen phosphate buffer (pH = 4.6) - acetonitrile (30:70, v:v) at a flow rate of 1 mL/min with UV detection at 210 nm was performed. The LC method was used for the simultaneous determination of STG, VLG, SXG and MET in the ranges of 5-200, 5-200, 0.5-80.0 and 20-800 μg/mL, respectively. The results were statistically compared with the reference method for each drug using one-way analysis of variance (ANOVA). The method developed was satisfactorily applied to the analysis of the pharmaceutical formulations and proved to be specific and accurate for the quality control of the cited drugs in pharmaceutical dosage forms.

Harvinder Singh Sohal, Arun Goyal, Rajeev Sharma, Rajshree Khare, Sanjay Kumar
DOI 10.5155/eurjchem.4.4.450-453.769

Multi component, one pot synthesis of various dihydropyrano[2,3-c]pyrazole derivatives from the condensation of ethyl acetoacetate, hydrazine, aromatic aldehyde and malononitrile has been described using glycerol, as environmentally benign, economical, and easily available solvent. The targeted molecules are obtained in excellent yield without use of any additional catalyst.

Salman Ahmad Khan, Abdullah Mohamed Asiri, Abdulrhim Alabbas Basheike, Kamlesh Sharma
DOI 10.5155/eurjchem.4.4.454-458.784

A series of pyrazole containing Schiff bases were synthesized, by the reaction of 3,5-dimethyl-1-phenylpyrazole-4-carboxaldehyde and the corresponding active amines under microwave irradiation. The structures of the synthesized compounds were established by spectroscopic data (FT-IR, 1H NMR, 13C NMR and ESI-MS) and elemental analyses. The anti-bacterial activity of these compounds were tested in vitro by the disc diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration using chloramphenicol as reference drug. All the molecules were modeled and optimized by using density functional theory, DFT/B3LYP method. Calculated descriptors, the lower unoccupied molecular orbital and the density were used to interpret the antibacterial activity of the compounds. The results showed that compound 3 is better inhibitor of both types of test bacteria as compared to chloramphenicol.


Short Communication

Mohsen Abdel-Motaal Gomaa, Abdel-Wahed Rashad Sayed, Ragab Ali Masoud
DOI 10.5155/eurjchem.4.4.459-461.821

Tetrahydroquinazolinone derivatives were synthesized in moderate to high yields via one‐pot three component Biginelli reaction of dimedone, urea or thiourea and corresponding aromatic aldehydes in the presence of molecular iodine as an efficient catalyst, in ethanol under reflux conditions. This protocol offers several advantages including good yields of products and easy experimental work‐up procedure.

Parthasaradhi Yerram, Rakhi Chowrasia, Suresh Seeka, Savitha Jyostna Tangenda
DOI 10.5155/eurjchem.4.4.462-466.847

A novel, efficient synthesis of 2-phenyl-2, 3-dihydroquinazolin-4(1H)-one derivatives is reported for the first time in PEG-400 by the reaction of various aldehydes, anthranilamide under catalyst-free conditions and the formation of product good to excellent yields. PEG-400 can be recovered and reused without any significant loss of activity.


Review Article

Ashraf Hassan Fekry Abd El-Wahab, Hany Mostafa Mohamed, Ahmed Mohamed El-Agrody, Ahmed Hammam Bedair
DOI 10.5155/eurjchem.4.4.467-483.775

This review deals with synthesis and reactions of some naphthopyrano derivatives and their applications. The main purpose of this review is to present a survey of literatures on the reactivity of naphthols and their derivatives toward α-cyanocinnamonitrile or ethyl α-cyanocinnamate derivatives and the reactions of β-enaminonitriles and β-enaminoesters with different electrophiles followed by nucleophilic reagents. Some of these reactions have been applied successfully to the synthesis of biologically important compounds.