Advances in Chemistry The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Synthesis of Disodium Salt of Sulfosuccinate Monoester from the Seed Oil of Terminalia catappa and Its Inhibitive Effect on the Corrosion of Aluminum Sheet in 1 M HCl Mon, 01 Sep 2014 09:36:34 +0000 Oil was extracted from the seed of Terminalia catappa and used to synthesize disodium salt of sulfosuccinate monoester using simple reaction mechanism. The disodium salt of sulfosuccinate monoester was applied as corrosion inhibitor of aluminum sheet in 1 M HCl via weight loss method. The adsorption was found to obey Langmuir isotherm. The results presented disodium salt of sulfosuccinate monoester as an efficient inhibitor of aluminum sheet corrosion in 1 M HCl. Adewale Adewuyi, Adewale Dare Adesina, and Rotimi A. Oderinde Copyright © 2014 Adewale Adewuyi et al. All rights reserved. Meticulous Overview on the Controlled Release Fertilizers Thu, 28 Aug 2014 12:57:47 +0000 Owing to the high demand for fertilizer formulations that will exhaust the possibilities of nutrient use efficiency (NUE), regulate fertilizer consumption, and lessen agrophysicochemical properties and environmental adverse effects instigated by conventional nutrient supply to crops, this review recapitulates controlled release fertilizers (CRFs) as a cutting-edge and safe way to supply crops’ nutrients over the conventional ways. Essentially, CRFs entail fertilizer particles intercalated within excipients aiming at reducing the frequency of fertilizer application thereby abating potential adverse effects linked with conventional fertilizer use. Application of nanotechnology and materials engineering in agriculture particularly in the design of CRFs, the distinctions and classification of CRFs, and the economical, agronomical, and environmental aspects of CRFs has been revised putting into account the development and synthesis of CRFs, laboratory CRFs syntheses and testing, and both linear and sigmoid release features of CRF formulations. Methodical account on the mechanism of nutrient release centring on the empirical and mechanistic approaches of predicting nutrient release is given in view of selected mathematical models. Compositions and laboratory preparations of CRFs basing on in situ and graft polymerization are provided alongside the physical methods used in CRFs encapsulation, with an emphasis on the natural polymers, modified clays, and superabsorbent nanocomposite excipients. Siafu Ibahati Sempeho, Hee Taik Kim, Egid Mubofu, and Askwar Hilonga Copyright © 2014 Siafu Ibahati Sempeho et al. All rights reserved. GC Analyses of Salvia Seeds as Valuable Essential Oil Source Wed, 27 Aug 2014 11:59:29 +0000 The essential oils of seeds of Salvia verbenaca, Salvia officinalis, and Salvia sclarea were obtained by hydrodistillation and analyzed by gas chromatography (GC) and GC-mass spectrometry. The oil yields (w/w) were 0.050, 0.047, and 0.045% in S. verbenaca, S. sclarea, and S. officinalis, respectively. Seventy-five compounds were identified. The essential oil composition of S. verbenaca seeds showed that over 57% of the detected compounds were oxygenated monoterpenes followed by sesquiterpenes (24.04%) and labdane type diterpenes (5.61%). The main essential oil constituents were camphor (38.94%), caryophyllene oxide (7.28%), and 13-epi-manool (5.61%), while those of essential oil of S. officinalis were α-thujone (14.77%), camphor (13.08%), and 1,8-cineole (6.66%). In samples of S. sclarea, essential oil consists mainly of linalool (24.25%), α-thujene (7.48%), linalyl acetate (6.90%), germacrene-D (5.88%), bicyclogermacrene (4.29%), and α-copaene (4.08%). This variability leads to a large range of naturally occurring volatile compounds with valuable industrial and pharmaceutical outlets. Mouna Ben Taârit, Kamel Msaada, Karim Hosni, and Brahim Marzouk Copyright © 2014 Mouna Ben Taârit et al. All rights reserved. Synthesis and Antimicrobial Studies of Pyrimidine Pyrazole Heterocycles Mon, 25 Aug 2014 10:58:22 +0000 Prompted from the diversity of the wider use and being an integral part of genetic material, an effort was made to synthesize pyrimidine pyrazole derivatives of pharmaceutical interest by oxidative cyclization of chalcones with satisfactory yield and purity. A novel series of 1,3-dimethyl-6-hydroxy-2,4-dioxo-5-(1′-phenyl-3′-aryl-1H-pyrazol-5′-yl)-1,2,3,4-tetrahydropyrimidines (5a–d) and 1,3-diaryl-6-hydroxy-4-oxo-2-thioxo-5-(1′-phenyl-3′-aryl-1H-pyrazol-5′-yl)-1,2,3,4-tetrahydropyrimidines (5e–l) has been synthesized. The structures of these compounds were established on the basis of FT-IR, 1H NMR, 13C NMR, and mass spectral analysis. All the synthesized compounds were screened for their antimicrobial activity against bacteria and fungi. Among all the compounds, 5g was found to be the most active as its MIC was 31.25 µg/mL against S. aureus and B. cereus. The compounds 5h, 5c, and 5e also possess antibacterial activity with MIC values as 62.50, 125.00, and 500.00 µg/mL, respectively. The compounds 5c and 5j were found to have antifungal activity against Aspergillus spp. As antifungal drugs lag behind the antibacterial drugs, therefore we tried in vitro combination of these two compounds with standard antifungal drugs (polyene and azole) against Aspergillus spp. The combination of ketoconazole with 5c and 5j showed synergy at 1 : 8 (6.25 : 50.00 µg/mL) and 1 : 4 (25 : 100 µg/mL) against A. fumigatus (ITCC 4517) and A. fumigatus (VPCI 190/96), respectively. Rakesh Kumar, Jyoti Arora, Sonam Ruhil, Neetu Phougat, Anil K. Chhillar, and Ashok K. Prasad Copyright © 2014 Rakesh Kumar et al. All rights reserved. XPS Study of the Chemical Structure of Plasma Biocopolymers of Pyrrole and Ethylene Glycol Sun, 24 Aug 2014 06:43:19 +0000 An XPS study about the structure of plasma biocopolymers synthesized with resistive radio frequency glow discharges and random combinations of ethylene glycol, pyrrole, and iodine, as a dopant, is presented in this work. The collisions of molecules produced structures with a great variety of chemical states based in the monomers, their combinations, crosslinking, doping, fragmentation, and oxidation at different levels in the plasma environment. Iodine appears bonded in the copolymers only at high power of synthesis, mainly as C–I and N–I chemical bonds. Multiple bonds as C≡C, C≡N, C=O, and C=N were found in the copolymers, without belonging to the initial reagents, and were generated by dehydrogenation of intermediate compounds during the polymerization. The main chemical states on PEG/PPy/I indicate that all atoms in pyrrole rings participate in the polymerization resulting in crosslinked, partially fragmented, and highly oxidized structures. This kind of analysis can be used to modify the synthesis of polymers to increase the participation of the most important chemical states in their biofunctions. Maribel González-Torres, Ma. Guadalupe Olayo, Guillermo J. Cruz, Lidia Ma. Gómez, Víctor Sánchez-Mendieta, and Francisco González-Salgado Copyright © 2014 Maribel González-Torres et al. All rights reserved. Cobalt(II) and Manganese(II) Complexes of Novel Schiff Bases, Synthesis, Charcterization, and Thermal, Antimicrobial, Electronic, and Catalytic Features Thu, 21 Aug 2014 06:24:21 +0000 Carbazoles containing two new Schiff bases (Z,Z)-N,N′-bis[(9-ethyl-9H-carbazole-3-yl)methylene]propane-1,3 diamine (L1) and (Z,Z)-N,N′-bis[(9-ethyl-9H-carbazole-3-yl)methylene]-2,2-dimethylpropane-1,3-diamine (L2) and their Co(II) and Mn(II) complexes were synthesized and characterized using various spectroscopic methods and thermal analysis, which gave high thermal stability results for the ligands and their cobalt complexes. The title compounds were examined for their antimicrobial and antifungal activities, which resulted in high activity values for the ligands and their manganese complexes. Oxidation reactions carried out on styrene and cyclohexene revealed that the complex compounds were the most effective catalysts for styrene oxidation, giving good selectivities than those of cyclohexene oxidation. Electronic features of the synthesized compounds were also reported within this work. Selma Bal and Sedat Salih Bal Copyright © 2014 Selma Bal and Sedat Salih Bal. All rights reserved. Dual Wavelength Spectrophotometric Method for Simultaneous Estimation of Atorvastatin Calcium and Felodipine from Tablet Dosage Form Thu, 21 Aug 2014 00:00:00 +0000 Atorvastatin calcium (ATR) and felodipine (FEL) are beneficial in combination for elderly people in management of hypertension and atherosclerosis. Aim of present study is to develop simple, accurate, and precise method for simultaneous quantitative estimation of ATR and FEL from combined tablet dosage form. Method involves simultaneous equation, using acetonitrile—double distilled water (70 : 30)—common solvent showing absorption maxima at 245 and 268 nm. Calibration curves determination for both drugs has been carried out in 0.1 N HCl, phosphate buffer pH 6.8, and acetonitrile (ACN)—water (70 : 30 V/V). Linearity range was observed in the concentration range of 2 to 12 µg/mL for FEL and 20 to 100 µg/mL for ATR. Percent concentration estimated for ATR and FEL was 100.12 ± 1.03 and 99.98 ± 0.98, respectively. The method was found to be simple, economical, accurate and precise and can be used for quantitative estimation of ATR and FEL. Namdeo R. Jadhav, Ramesh S. Kambar, and Sameer J. Nadaf Copyright © 2014 Namdeo R. Jadhav et al. All rights reserved. Philicity and Fugality Scales for Organic Reactions Mon, 18 Aug 2014 07:48:29 +0000 Theoretical scales of reactivity and selectivity are important tools to explain and to predict reactivity patterns, including reaction mechanisms. The main achievement of these efforts has been the incorporation of such concepts in advanced texts of organic chemistry. In this way, the modern organic chemistry language has become more quantitative, making the classification of organic reactions an easier task. The reactivity scales are also useful to set up a number of empirical rules that help in rationalizing and in some cases anticipating the possible reaction mechanisms that can be operative in a given organic reaction. In this review, we intend to give a brief but complete account on this matter, introducing the conceptual basis that leads to the definition of reactivity indices amenable to build up quantitative models of reactivity in organic reactions. The emphasis is put on two basic concepts describing electron-rich and electron-deficient systems, namely, nucleophile and electrophiles. We then show that the regional nucleophilicity and electrophilicity become the natural descriptors of electrofugality and nucleofugality, respectively. In this way, we obtain a closed body of concepts that suffices to describe electron releasing and electron accepting molecules together with the description of permanent and leaving groups in addition, nucleophilic substitution and elimination reactions. Rodrigo Ormazábal-Toledo and Renato Contreras Copyright © 2014 Rodrigo Ormazábal-Toledo and Renato Contreras. All rights reserved. Effect of γ-Irradiation and Calcination Temperature of Nanosized ZnO/TiO2 System on Its Structural and Electrical Properties Mon, 18 Aug 2014 06:57:33 +0000 ZnO/TiO2 powders were synthesized by sol-gel method using ammonium hydroxide. The effects of calcination temperature (500–1000°C) and gamma rays (with doses from 25 to 150 kGy) on the phases present and their electrical properties were investigated. The results revealed that heating the system investigated at 500°C led to the formation of ZnTiO3-rohom and TiO2-rutile. The degree of crystallinity of the phases produced increased by increasing the calcination temperature. When heating at 1000°C, ZnTiO3-rohom turned to ZnTiO3-cubic but the rutile phase remained stable. γ-Irradiation decreased considerably the crystallite size of the rutile phase from 146 to 63 nm and that of ZnTiO3-cubic decreased from 101 to 39 nm. This treatment led also to the creation of holes in the matrix of irradiated solids which increased the mobility of charge carriers (electrons) leading to a significant increase in the electrical conductivity reaching to 102 to 103-fold. Abdelrahman A. Badawy, Shaymaa E. El-Shafey, Suzan Abd El All, and Gamil A. El-Shobaky Copyright © 2014 Abdelrahman A. Badawy et al. All rights reserved. Hydroboration of Substituted Cyclopropane: A Density Functional Theory Study Mon, 18 Aug 2014 00:00:00 +0000 The hydroboration of substituted cyclopropanes has been investigated using the B3LYP density functional method employing 6-31G** basis set. Borane moiety approaching the cyclopropane ring has been reported. It is shown that the reaction proceeds via a three-centered, “loose” and “tight,” transition states when boron added to the cyclopropane across a bond to a substituents. Single point calculations at higher levels of theory were also performed at the geometries optimized at the B3LYP level, but only slight changes in the barriers were observed. Structural parameters for the transition state are also reported. Satya Prakash Singh and Pompozhi Protasis Thankachan Copyright © 2014 Satya Prakash Singh and Pompozhi Protasis Thankachan. All rights reserved. A Rapid Extractive Spectrophotometric Method for the Determination of Tin with 6-Chloro-3-hydroxy-2-(2′-thienyl)-4-oxo-4H-1-benzopyran Thu, 14 Aug 2014 09:49:20 +0000 An extractive spectrophotometric method for the determination of the trace amounts of tin has been carried out by employing 6-chloro-3-hydroxy-2-(2′-thienyl)-4-oxo-4H-1-benzopyran (in acetone) (CHTB) for the complexation of the metal ion in HCl medium. The colored species thus produced is quantitatively extracted into dichloromethane and shows the maximum absorbance at 432–437 nm. The method obeys Beer’s law in the range 0.0–1.3 μg mL−1 of tin with molar absorptivity and Sandell’s sensitivity of  L mol−1 cm−1 and 0.0020 μg Sn cm−2, respectively, at 435 nm. The method is highly selective and free from the interference of a large number of elements including platinum metals. The ratio of metal to ligand in the extracted species is 1 : 2. Utilizing this method, the analysis of various synthetic and technical samples including gun metal and tin can have been carried out satisfactorily. Ramesh Kataria and Harish Kumar Sharma Copyright © 2014 Ramesh Kataria and Harish Kumar Sharma. All rights reserved. Synthesis of Highly Stable Cobalt Nanomaterial Using Gallic Acid and Its Application in Catalysis Mon, 11 Aug 2014 11:43:49 +0000 We report the room temperature (25–30°C) green synthesis of cobalt nanomaterial (CoNM) in an aqueous medium using gallic acid as a reducing and stabilizing agent. pH 9.5 was found to favour the formation of well dispersed flower shaped CoNM. The optimization of various parameters in preparation of nanoscale was studied. The AFM, SEM, EDX, and XRD characterization studies provide detailed information about synthesized CoNM which were of 4–9 nm in dimensions. The highly stable CoNM were used to study their catalytic activity for removal of azo dyes by selecting methyl orange as a model compound. The results revealed that 0.4 mg of CoNM has shown 100% removal of dye from 50 μM aqueous solution of methyl orange. The synthesized CoNM can be easily recovered and recycled several times without decrease in their efficiency. Saba Naz, Abdul Rauf Khaskheli, Abdalaziz Aljabour, Huseyin Kara, Farah Naz Talpur, Syed Tufail Hussain Sherazi, Abid Ali Khaskheli, and Sana Jawaid Copyright © 2014 Saba Naz et al. All rights reserved. A Simple and Advantageous Synthesis of the Privileged 1,4-Benzodiazepine Nucleus Mon, 11 Aug 2014 00:00:00 +0000 A novel domino approach has been described for an easy access of the privileged nucleus of 5-carbomethoxy substituted 1,4-benzodiazepin-2-ones 4(a–i) from an in situ methanolic hydrolysis of an incipient species formed from the interaction of 1-chloroacetylisatin 2(a–i), hexamethyldisilazane, and n-butyl lithium. The reaction is believed to take place through a consecutive series of intramolecular reactions in a cascade to first generate a highly reactive carbene intermediate 3(a–i) from 1-chloroacetylisatin and n-butyl lithium which is simultaneously trapped by hexamethyldisilazane before undergoing its in situ hydrolysis with methanol to initiate its concomitant cyclocondensation to produce 4(a–i) in high yield and purity. Neetu Jain and Dharma Kishore Copyright © 2014 Neetu Jain and Dharma Kishore. All rights reserved. A Conformational Model for MTPA Esters of Chiral N-(2-Hydroxyalkyl)acrylamides Sun, 10 Aug 2014 11:07:57 +0000 The absolute stereochemistry of novel chiral N-(2-hydroxylalkyl)acrylamides prepared by a lipase-catalyzed resolution was successfully determined by 1H NMR of their MTPA esters. The method was validated for this particular case by computational experiments. Eduardo M. Rustoy, Alicia Baldessari, and Leandro N. Monsalve Copyright © 2014 Eduardo M. Rustoy et al. All rights reserved. An Efficient One Pot Protocol to the Annulation of Face “d” of Benzazepinone Ring with Pyrazole, Isoxazole, and Pyrimidine Nucleus through the Corresponding Oxoketene Dithioacetal Derivative Wed, 06 Aug 2014 00:00:00 +0000 A highly facile single step approach to the annulation of face “d” of benzazepinone nucleus with pyrazole, isoxazole, and pyrimidine ring has been described. The annulation proceeded smoothly on the reaction of oxoketene dithioacetal derivative 3 with (i) NH2–NH2·H2O, (ii) NH2OH·HCl, (iii) acetamidine hydrochloride, (iv) guanidine nitrate, (v) urea, and (vi) thiourea which yielded the pyrazolo, isoxazolo, and pyrimido annulated analogues of benzazepinone 4–9, respectively, in acceptable yields. The 4-ketene dithioacetal analogue of 7-fluorobenzo[b]azepine-2,5-dione (3) was in turn obtained from the reaction of 7-fluoro-3,4-dihydro-1H-benzo[b]azepine-2,5-dione (2) (with CS2 + CH3I in presence of t-BuOK). 7-Fluoro-3,4-dihydro-1H-benzo[b]azepine-2,5-dione (2) resulted from the acylation of p-fluoroaniline with succinyl chloride followed by cyclocondensation of the later with polyphosphoric acid (PPA). Aditi Anand, Navjeet Kaur, and Dharma Kishore Copyright © 2014 Aditi Anand et al. All rights reserved. Baphia nitida Leaves Extract as a Green Corrosion Inhibitor for the Corrosion of Mild Steel in Acidic Media Mon, 04 Aug 2014 11:09:45 +0000 The inhibiting effect of Baphia nitida (BN) leaves extract on the corrosion of mild steel in 1 M H2SO4 and 2 M HCl was studied at different temperatures using gasometric and weight loss techniques. The results showed that the leaves extract is a good inhibitor for mild steel corrosion in both acid media and better performances were obtained in 2 M HCl solutions. Inhibition efficiency was found to increase with increasing inhibitor concentration and decreasing temperature. The addition of halides to the extract enhanced the inhibition efficiency due to synergistic effect which improved adsorption of cationic species present in the extract and was in the order KCl < KBr < KI suggesting possible role of radii of the halide ions. Thermodynamic parameters determined showed that the adsorption of BN on the metal surface is an exothermic and spontaneous process and that the adsorption was via a physisorption mechanism. V. O. Njoku, E. E. Oguzie, C. Obi, and A. A. Ayuk Copyright © 2014 V. O. Njoku et al. All rights reserved. Pulsed Supersonic Beams from High Pressure Source: Simulation Results and Experimental Measurements Sun, 03 Aug 2014 08:52:13 +0000 Pulsed beams, originating from a high pressure, fast acting valve equipped with a shaped nozzle, can now be generated at high repetition rates and with moderate vacuum pumping speeds. The high intensity beams are discussed, together with the skimmer requirements that must be met in order to propagate the skimmed beams in a high-vacuum environment without significant disruption of the beam or substantial increases in beam temperature. U. Even Copyright © 2014 U. Even. All rights reserved. Chiral Recognition by Fluorescence: One Measurement for Two Parameters Wed, 23 Jul 2014 00:00:00 +0000 This outlook describes two strategies to simultaneously determine the enantiomeric composition and concentration of a chiral substrate by a single fluorescent measurement. One strategy utilizes a pseudoenantiomeric sensor pair that is composed of a 1,1′-bi-2-naphthol-based amino alcohol and a partially hydrogenated 1,1′-bi-2-naphthol-based amino alcohol. These two molecules have the opposite chiral configuration with fluorescent enhancement at two different emitting wavelengths when treated with the enantiomers of mandelic acid. Using the sum and difference of the fluorescent intensity at the two wavelengths allows simultaneous determination of both concentration and enantiomeric composition of the chiral acid. The other strategy employs a 1,1′-bi-2-naphthol-based trifluoromethyl ketone that exhibits fluorescent enhancement at two emission wavelengths upon interaction with a chiral diamine. One emission responds mostly to the concentration of the chiral diamine and the ratio of the two emissions depends on the chiral configuration of the enantiomer but independent of the concentration, allowing both the concentration and enantiomeric composition of the chiral diamine to be simultaneously determined. These strategies would significantly simplify the practical application of the enantioselective fluorescent sensors in high-throughput chiral assay. Shanshan Yu and Lin Pu Copyright © 2014 Shanshan Yu and Lin Pu. All rights reserved. Study of Swelling Properties and Thermal Behavior of Poly(N,N-Dimethylacrylamide-co-Maleic Acid) Based Hydrogels Tue, 22 Jul 2014 08:38:55 +0000 Hydrogels copolymers N,N-dimethylacrylamide (DMA) and maleic acid (MA) were prepared by free-radical polymerization at 56°C in aqueous solution, using N,N-methylenebisacrylamide (NMBA) as cross-linking agent and potassium persulfate (KPS) as initiator. The effects of comonomer composition, cross-linker content, and variation of pH solutions on the swelling behavior of polymers were investigated. The obtained results showed an increase of the swelling of poly(N,N-dimethylacrylamide-co-maleic acid) (P(DMA-MAx)) as the content of maleic acid increases in the polymeric matrix, while they indicate a great reduction of the degree of swelling as the cross-linking agent ratio increases. It was also shown that the swelling of copolymer hydrogels increased with the increase of pH and the maximum extent was reached at pH 8.7 in all compositions. Fourier transform infrared spectroscopy (FTIR) revealed the existence of hydrogen bonding interactions between the carboxylic groups of MA and the carbonyl groups of DMA. Differential scanning calorimetry analysis (DSC) showed an increase of the glass-transition temperature () as concentrations of MA and NMBA increased. Thermogravimetric analysis (TGA) of copolymers was performed to investigate the degradation mechanism. Sadjia Bennour and Fatma Louzri Copyright © 2014 Sadjia Bennour and Fatma Louzri. All rights reserved. Selenium (Se) Regulates Seedling Growth in Wheat under Drought Stress Tue, 22 Jul 2014 06:51:32 +0000 Selenium (Se) is an essential micronutrient with a range of physiological and antioxidative properties. Reports regarding effect of Se application on plants growth and development are not consistent. The identification of effective Se dose and application method is crucial for better understanding of Se translocation within crop plants under drought stress. The present study aimed at investigating the role of Se supplementation in improving the drought tolerance potential of wheat at early growth stages. Two wheat genotypes (Kohistan-97 and Pasban-90) were grown in plastic pots (8 × 12 cm) in green/wire-house experiments. Results demonstrated that the growth and biomass of seedlings increased at high Se foliar concentrations and decreased at low and high Se fertigation levels. The seedlings exhibited the highest values for plant height stress tolerance index (PHSI), root length stress tolerance index (RLSI), dry matter stress tolerance index (DMSI), and fresh matter stress tolerance indices (FMSI) at Se fertigation level of 7.35 μM, whereas Se foliar treatment of 7.06 μM resulted in maximum values for these indices. The seedlings foliarly sprayed with Se maintained higher DMSI and FMSI than those fertigated with Se which suggests that Se foliar spray is more effective than Se fertigation for improving drought tolerance. Fahim Nawaz, Muhammad Yasin Ashraf, Rashid Ahmad, Ejaz Ahmad Waraich, and Rana Nauman Shabbir Copyright © 2014 Fahim Nawaz et al. All rights reserved. Synthesis and Antimicrobial Activity of New Schiff Base Compounds Containing 2-Hydroxy-4-pentadecylbenzaldehyde Moiety Mon, 21 Jul 2014 00:00:00 +0000 Various novel Schiff base compounds have been synthesized by reaction of 2-hydroxy-4-pentadecylbenzaldehyde with substituted benzothiophene-2-carboxylic acid hydrazide and different substituted aromatic or heterocyclic amines in the presence of acetic acid in ethanol. The structures of all these compounds were confirmed by elemental analysis, IR, 1H-NMR, 13C-NMR, and mass spectral data and have been screened for antibacterial and antifungal activity. Gadada Naganagowda, Reinout Meijboom, and Amorn Petsom Copyright © 2014 Gadada Naganagowda et al. All rights reserved. Solar UV-Assisted Pretreatment of River Water Samples for the Voltammetric Monitoring of Nickel and Cobalt Ultratraces Mon, 21 Jul 2014 00:00:00 +0000 The application of solar UV radiation as sample digestion method is reported. The method is employed in adsorptive stripping voltammetric determination of nickel and cobalt in river water samples. The river water samples were collected from downstream of Warnow River (Germany) and acidified to pH of by addition of ultrapure 65% HNO3. Furthermore, 3.4 mgL−1 ultrapure hydrogen peroxide solution was added to the samples as photochemical reaction initiator. The samples were transferred to UV-A transparent polyethylene terephthalate bottles and put in the sunshine for UV irradiation for six and 12 hours at a UV-A intensity of 3.90 mW/m2. The comparison of the concentration values showed that, 6 hours of solar UV irradiation at 3.90 mW/m2 UV-A intensity is not sufficient to complete the digestion process though it yields much better results than the undigested original sample. However, 12 hours of solar UV-A irradiation under similar conditions is almost as effective as a 30 W artificial UV lamp (254 nm) and can be applied to the digestion of dissolved organic carbon in trace nickel (II) and cobalt (II) analysis in natural waters such as river water, lake waters, and well waters. Gelaneh Woldemichael and Gerd-Uwe Flechsig Copyright © 2014 Gelaneh Woldemichael and Gerd-Uwe Flechsig. All rights reserved. Heteroring Annulated Benzimidazolinone Condensed Azepinone Derivatives: A New Class of Highly Potent Antioxidants Sun, 20 Jul 2014 00:00:00 +0000 A new class of benzimidazolinone condensed azepinone derivatives annulated on its face “d” with pyrazole, isoxazole, pyrimidine, benzodiazepine, and benzothiazepine nucleus in 3–8, respectively, have been evaluated for their antioxidant activity by DPPH method. Results indicate these to belong to a novel class of highly potent antioxidant agents. Neha Garg, Priyanka Jain, and D. Kishore Copyright © 2014 Neha Garg et al. All rights reserved. Synthesis of Disperse Dyes from Pyridone and Resorcinol Coupled to Diazotized 2-Amino-4-chloro-5-formylthiazole and Application to Polyester Thu, 17 Jul 2014 10:31:05 +0000 The aim of this study was to synthesize disperse dyes in the derivative of 2-amino-4-chloro-5-formylthiazole by conventional diazotization and couplings with pyridone and resorcinol. The dyes were characterized by visible absorption spectroscopy, IR spectral studies, and 1H and 13C NMR. The pyridone and resorcinol substituted dyes exhausted well with good depth on 100% polyester fabrics with a shade of brown and purple colours, respectively. The heteroatom and the intrinsic conjugation in the thiazole structure results in high bathochromic shifts and lead to brightness of shades. The dyed fabrics showed very good to excellent wash fastness and moderate to good light and perspiration fastness properties. Yusuf Y. Lams, P. O. Nkeonye, K. A. Bello, M. K. Yakubu, and A. O. Lawal Copyright © 2014 Yusuf Y. Lams et al. All rights reserved. The Biological Side of Water-Soluble Arene Ruthenium Assemblies Thu, 17 Jul 2014 07:55:44 +0000 This review article covers the synthetic strategies, structural aspects, and host-guest properties of ruthenium metalla-assemblies, with a special focus on their use as drug delivery vectors. The two-dimensional metalla-rectangles show interesting host-guest possibilities but seem less appropriate for being used as drug carriers. On the other hand, metalla-prisms allow encapsulation and possible targeted release of bioactive molecules and consequently show some potential as drug delivery vectors. The reactivity of these metalla-prisms can be fine-tuned to allow a fine control of the guest’s release. The larger metalla-cubes can be used to stabilize the formation of G-quadruplex DNA and can be used to encapsulate and release photoactive molecules such as porphins. These metalla-assemblies demonstrate great prospective in photodynamic therapy. Bruno Therrien and Julien Furrer Copyright © 2014 Bruno Therrien and Julien Furrer. All rights reserved. Cu(II) Complexes of Isoniazid Schiff Bases: DNA/BSA Binding and Cytotoxicity Studies on A549 Cell Line Mon, 14 Jul 2014 10:26:29 +0000 A series of isonicotinoyl hydrazones have been synthesized via template method and were complexed to Cu(II). The ligands are coordinated to Cu(II) ion through the enolic oxygen and azomethine nitrogen resulting in a square planar geometry. The CT-DNA and bovine serum albumin binding propensities of the compounds were determined spectrophotometrically, the results of which indicate good binding propensity of complexes to DNA and BSA with high binding constant values. Furthermore, the compounds have been investigated for their cytotoxicities on A549 human lung cancer cell. Also the mode of cell death was examined employing various staining techniques and was found to be apoptotic. Pulipaka Ramadevi, Rinky Singh, Akhilesh Prajapati, Sarita Gupta, and Debjani Chakraborty Copyright © 2014 Pulipaka Ramadevi et al. All rights reserved. Synthesis of New Imidazolidine and Tetrahydropyrimidine Derivatives Mon, 14 Jul 2014 08:10:59 +0000 Synthesis of new imidazolidine and tetrahydropyrimidine derivatives 3a, b and 4a–c as cyclic 1,3-diamines under two reaction conditions (A and B) is described. Under reaction conditions-A, a suspension of (E)-2-cyano-2-(oxazolidin-2-ylidene)ethanethioamide 1 (1 eq.) and diaminoalkanes 2a–e (2 eq.) in absolute ethanol is heated under reflux for 16–22 h to afford 3a, b and 4a–c. Alternatively, under reaction conditions-B, a solution of thioamide 1 (1 eq.) in diaminoalkanes 2a–e (3 eq.) is stirred under solvent-free conditions at room temperature for 3 days to give desired products. Reaction conditions-A for having higher yields, shorter reaction times, and required less diamines is more effective than reaction conditions-B. Oxazolidine ring opening is observed by reacting compound 1 with all of the diamines 2a–e, but the thioamide group only reacts with nonbulky diamines 2a, b. The chemical structures of novel compounds were confirmed by 1H NMR, 13C NMR, elemental analysis, and FT-IR spectrometry. Hamid Beyzaei, Reza Aryan, and Zahra Keshtegar Copyright © 2014 Hamid Beyzaei et al. All rights reserved. Appraisal on Textured Grain Growth and Photoconductivity of ZnO Thin Film SILAR Sun, 13 Jul 2014 11:49:21 +0000 ZnO thin films were prepared by successive ionic layer adsorption reaction (SILAR) method. The textured grain growth along c-axis in pure ZnO thin films and doped with Sn was studied. The structural analysis of the thin films was done by X-ray diffraction and surface morphology by scanning electron microscopy. Textured grain growth of the samples was measured by comparing the peak intensities. Textured grain growth and photo current in ZnO thin films were found to be enhanced by doping with Sn. ZnO thin film having good crystallinity with preferential (002) orientation is a semiconductor with photonic properties of potential benefit to biophotonics. From energy dispersive X-ray analysis, it is inferred that oxygen vacancy creation is responsible for the enhanced textured grain growth in ZnO thin films. Deepu Thomas, Sunil C. Vattappalam, Sunny Mathew, and Simon Augustine Copyright © 2014 Deepu Thomas et al. All rights reserved. Synthesis and Characterization of Tolvaptan Impurities Thu, 10 Jul 2014 11:45:34 +0000 Twenty-six possible as well as observed impurities during the preparation of Tolvaptan have been identified, prepared, and characterized by HPLC (high performance liquid chromatography), NMR (nuclear magnetic resonance), and mass spectra. Control of these impurities, formed during various stages of Tolvaptan preparation, has been mentioned in this paper. Madhuresh Kumar Sethi, Vijendra Singh Rawat, Jayaprakash Thirunavukarasu, Rajakrishna Yerramalla, and Anish Kumar Copyright © 2014 Madhuresh Kumar Sethi et al. All rights reserved. Azadirachta indica Mediated Bioactive Lyocell Yarn: Chemical and Colour Characterization Tue, 01 Jul 2014 07:29:04 +0000 The study deals with preparing aesthetic textiles using methanolic extract of Azadirachta indica leaves. The extract with metallic and natural mordents was utilized to create various shades on lyocell yarn using exhaust technique of dyeing. Aesthetic values of dyed yarns were analyzed in terms of colourimetric parameters, that is, CIE and colour fastness. The attachment of Azadirachta indica compounds has been confirmed by using infrared spectroscopy (IR) analysis. The dyed samples exhibit moderate to good fastness properties. The study showed that lyocell yarn treated at 15% (owf) methanolic extract of Azadirachta indica leaves can be utilized as effective bioactive textiles. Azadirachta indica is an alternative to synthetic antimicrobial agents. This bioactive yarn can be used in fashion as well as in medicinal industry. B. H. Patel, K. U. Desai, and P. K. Jha Copyright © 2014 B. H. Patel et al. All rights reserved.