Asian Journal of Chemistry

1-8

Authors: Pallavi Jain *, Dinesh Kumar and Sulekh Chandra

Due to their borad profiles of biological activities, transition metal complexes containing semicarbazones and thiosemicarbazones become largely appealing. This mini review focused on the recent developments in last 5 years on the biological applications of Co(II) and Ni(II) complexes of semicarbazones and thiosemicarbazones.

18-24

Authors: S.M. Ho *, M.A. Mahadik , J.S. Jang and V.N. Singh

Thin films have been used for many applications. Hydrogen production from solar water splitting has been considered as a key solution to the energy and environmental issues. The tuned band gap alignments in metal chalcogenides/metal oxides heterostructure enable efficient separation of photogenerated electrons and holes, leading to the effective hydrogen production. We sensitize these structures by hydrothermal methods and evaluate the performance toward hydrogen generation. This work shows a brief overview of photoelectrochemical hydrogen production, progress and ongoing sprints. Here, different metal chalcogenides were deposited on metal oxides (TiO2 and Fe2O3) in order to improve the photoelectrochemical performance by reducing recombination of photogenerated electron–hole pairs and facilitate hole transport at the metal chalcogenides/metal oxides/electrolyte interface. The study includes chalcogenides/metal oxides heterostructure designs and electrochemistry and solar hydrogen generation are brought together, illustrating the promise and challenge of photoelectrochemistry

41-44

Authors: Vijay Kumar Pujari *, Srilalitha Vinnakota , Ramana Kumar Kakarla and Sridhar Marojua

A green one pot synthetic protocol method for 1-(2-chloropyridin-3-yl)-3-substituted urea derivatives from 2-chloropyridin-3-amine and tert-butyl substituted carbamates by using bis(trimethylaluminum)- 1,4-diazabicyclo[2,2,2]octane (DABAL-Me3) under microwave irradiation is developed. The compound structures established by spectral data such as IR, 1 H NMR and mass spectroscopy. All the synthesized compounds were tested in vitro antimicrobial activity.

51-55

Authors: Jai Devi* , Nisha Batra and Jyoti Yadav

Transition metal complexes of cobalt(II), nickel(II), copper(II) and zinc(II) of isatinimine Schiff base ligands (HL1-HL2) derived from isatin 5-chloro-2-hydroxy aniline (HL1), 2-amino-4-nitrophenol (HL2) and heterocyclic nitrogen base 8-hydroxyquinoline have been synthesized. All the metal complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility, SEM and spectroscopic techniques (IR, UV-visible, NMR and ESR). Transition metal complexes existed as octahedral or distorted octahedral geometries around metal centres with the donation of carbonyl oxygen, azomethine nitrogen and deprotonated enolic oxygen, whereas ligand 8-hydroxyquinoline existed as monobasic bidentate ON coordinating through oxygen of hydroxyl group and nitrogen of quinoline ring. The complexes were found to be non-electrolytic in nature.

61-72

Authors: Anil Kumar , Y.F. Nadaf and C.G. Renuka *

The electronic absorption and emission spectra of laser dyes quinoline-390 and rhodamine-800 in distinct organic solvents have been analyzed to understand conventional interactions of solvents on the intensities, peak positions of both absorption and emission spectrum. The relationship between absorption spectrum (λmax) and solvatochromic constants (ε, n, E) indicates that the peak positions are fundamentally influenced by non-specific and specific kind of interactions between the solute and solvent. Solvent effects on the electronic absorption band shift are characteristics of the degree of charge rearrangement of the solute molecules upon electronic excitation. These spectral shifts reflect the effect of the equilibrium solvents association across the energized solute particle, which adjusts inertially as a result of quick charge realignment upon radiative deactivation to the lowest electronic state. Spectral regression study techniques were carried out for the qualitative chemical analyses of these compounds, which provides an opportunity to assess electrical-optical molecular constants within the excited electronic conditions. Further TD-DFT computational techniques for optimized geometry, electronic structure and Mulliken charge distribution in vacuum and ethanol solvent were carried out to acquire additional knowledge of the molecular arrangement and electronic properties of these laser dyes.

79-82

Authors: Balasaheb P. Pagar

The reaction of methylbenzo[h][1,6]naphthyridine (1) with thiourea yield 4-chloro-12-methyl-16,17- dihydro-15-thia-6,11-diaza-cyclopenta[a]phenanthrene-7-thiol (2). The chemistry of compound 2 is explored to obtained iminothioether derivatives (3a-h) in good yields. The structures of newly synthesized compounds were confirmed by spectral data and elemental analysis. The antimicrobial activity of newly synthesized compounds were studied against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeroginosa, Proteus valgaris, Bacillus cereus, Streptococcus sp. and Bacillus megaterium by the agar well diffusion method. Compounds 3d, 3f and 3h showed moderate antimicrobial activity.

89-98

Authors: M.C. Somasekhara Reddy *, K. Sridevi, S.M. Sarvar Jahan and G.V. Subba Reddy

A plant based natural surfactant was extracted from fruit pericarp of Sapindus mukorossi, commonly known as soap nuts. The natural surfactant was used for the treatment of the soils which were contaminated with hydrophobic organic compounds like organic dye, Sudan III and the dye was removed/recovered from the soils. This biosurfactant has great advantages when used in environmental remediation as it is environment friendly in nature. Using a simple water extraction of fruit pericarp powder, the natural surfactant was prepared. The natural surfactant solutions were employed to enhance the aqueous solubility of hydrophobic organic compounds like organic dye, Sudan III and to desorb organic dye Sudan III from contaminated soils in batch experiments. The performance of natural surfactant for the removal of Sudan III was compared with that of commercial surfactants like sodium dodecyl sulphate (SDS) (anionic surfactant), cetyltrimethylammonium bromide (CTAB) (cationic surfactant) and Triton X-100 (TX 100) (non-ionic surfactant). The aqueous solubility enhancement of Sudan III dye in presence of 0.04 M of NaCl was increased in case of non-ionic surfactants like natural surfactant (NS) and TX 100. The solubility of Sudan III dye in presence of 0.04 M of NaCl was decreased in case of ionic surfactants like SDS and CTAB. The desorption behaviour observed for natural surfactant was similar to TX 100 solutions. The natural surfactant solution performance was more or less similar to synthetic surfactants and the removal capacity of surfactant was given in increasing order as TX 100 > NS > SDS > CTAB.

105-108

Authors: Vu Dinh Tien, Vu Van Vu and Tran Khac Vu*

The paper described the preparation of enantiomers of gossypol and apogossypol from racemic gossypol via a two-step procedure. In the first step, D-tryptophan methyl ester was used as an effective agent to resolve racemic gossypol into (–)-gossypol and (+)-gossypol. Next, the deformylation reaction of the corresponding (–)-gossypol and (+)-gossypol was conducted in sodium hydroxide solution, followed by sulfuric acid neutralization in inert atmosphere and the resulting precipitate was filtered and washed with water to give (–)-apogossypol and (+)-apgossypol, respectively in high yields and in high enantiomeric excesses.

114-120

Authors: L.H. Khdium and A.A. Ali Drea*

B3LYP, Lanl2DZ basis sets at density functional theory (DFT) method has been used on a ground state geometry optimized for all proposed structures that have been involved in this study. Structural parameters such as bond lengths, bond angles and dihedral angles have been calculated in the same way to achieve a global reactivity description of Pt(IV) complex. We suggested a minimal energy structure of diaminobis((4-hydroxy-4-butanol)oxy)platinum(IV) chloride complex (DOP) as a new chemotherapy formula of cis-platinum complex. The reactive site of nucleophilic attachment at DOP occurs on carbon atoms due to their positive charge, while other atoms (nitrogen, oxygen, chlorine) are carried negative charges due to the delocalization of electron pair by a resonance effect. Bonds of Pt-Cl with 2.290 Å are more reactive bounds toward the replacement reactions than other chemical bonds in the DOP complex. Investigation revealed that the thermodynamic functions values are increased due to increasing vibrational intensities of cisplatin complex. The fourth transition state (TS4) is the most probable transition state than other suggested transition states for both guanine and adenine bases. The TS4 of platinum complex binding with guanine is the most probable by a factor of -18.134 a.u. of optimization energy value than other suggested states. TS4-guanine is the most probable than other suggested states by factor 7.354 kcal/mol of zero point energy (ZPE). Hence, platinum complex (DOP) is binded with guanine base of DNA through N7

128-134

Authors: S.S. Chine and C.S. Patil *

An efficient method for the synthesis of 1,4-dihydropyridine derivatives from various aryl or heteroaryl aldehydes, β-ketoester and ammonium acetate in presence of laterite catalyst in ethanol under ultrasonication is reported. Catalyst study done with wet chemical analysis, FT-IR, XRD, SEM and EDS techniques. The catalyst can be recovered and reused without noticeable loss of activity even after five cycles.

139-142

Authors: Fatema Tabassum *, Choudhury Mahmood Hasan, Mohammad Mehedi Masud, Sheikh Nazrul Islam and Monira Ahsan

The methanolic extract of the leaves of Ravenia spectabilis was investigated for isolation of secondary metabolites and evaluation of bioactivities. Two alkaloids ravenoline (1) and arborinine (2) were obtained by using vacuum liquid chromatography, gel permeation chromatography and TLC. The compounds were identified by NMR spectroscopy and by comparing the NMR data with those published in the literature. The pure compounds and the petroleum ether, carbon tetrachloride, chloroform and aqueous soluble fractions of the crude methanolic extract of the plant were evaluated for thrombolytic, antioxidant and antimicrobial properties. In the study for thrombolytic property, the pure compounds and different fractions showed thrombolytic activity ranging from 30.43 to 48.85 % as compared to standard streptokinase (74.34 %). All the fractions and the pure compounds showed mild to moderate antibacterial activity. Carbon tetrachloride fraction showed moderate antioxidant activity (97.53 μg/mL) as compared to BHT (27.50 μg/mL), whereas other fractions showed mild antioxidant activity.

148-156

Authors: M. Pragathi * and K. Hussain Reddy

Designing of dinucleating ligands, with an additional donor atom that can bridge two metals in a more or less fixed geometry has rapidly developed in recent years. Part of the interest stems from the fact that the corresponding complexes are often studied as enzyme mimics. Two quinquedentate ligands have been synthesized by condensing salicylaldehyde/o-hydroxy- acetophenone with 2-hydroxy-1,3- propanediamine. The ligands and their metal complexes are synthesized and characterized by physicochemical and spectral analysis. Electrochemical behaviour of the complexes is investigated through cyclic voltammetric studies. E1/2 values are observed at 0.360 and 0.331 V vs. Ag/AgCl for the complexes. The non-equivalent current in cathodic and anodic peaks (ic/ia = 1.224 and 1.065 at 100 mV s-1) for metal complexes indicate quasi-reversible behaviour. Binding interactions of the dinuclear copper(II) complexes with calf thymus DNA are investigated using absorption spectrophotometry. Cleavage activities of these complexes are uncovered on a double stranded pBR plasmid DNA by using gel electrophoresis experiments in different conditions. At micromolar concentration, the ligands exhibit no significant activity, whereas the metal complexes show significantly enhanced nuclease activity due to the presence of metal ions. Copper complexes cleave DNA more effectively in the presence of oxidant. This is consistent with the increased production of hydroxyl radicals by cuprous ions similar to the well known “Fenton reaction”

161-164

Authors: Rajesh Kumar Sharma* and V. Vaijayanthi

Sol-gel technique was used to prepare glasses of the (35-x)B2O3-65Bi2O3-x Fe2O3 (0.1≤ x ≤ 0.4) system (A1-A4: x = 0.1, 0.2, 0.3, 0.4). The local structure and symmetry around trivalent iron were determined by studying X-band powder EPR spectra at room temperature. The EPR spectra of trivalent iron in glass samples are characterized by a more intense line at g = 4.2 and a less intense line at g = 2.0. The EPR line at g = 4.2 is attributed to trivalent iron in rhombic octahedral environment. The line at g = 2.0 is because of two or more trivalent iron coupling through dipole-dipole interactions in distorted octahedral symmetry. The intensity of EPR lines is dependent of Fe2O3 content in the glass samples. At higher concentration of Fe2O3, EPR line at g = 4.2 is less intense whereas the line at g = 2.0 is more intense which is ascribed to the formation of clusters of trivalent iron. The electronic spectra of glass samples show two broad bands corresponding to d-d transition in the range 410-450 nm and in the range 530-570 nm, respectively which are assigned to trivalent iron in distorted octahedral environment

169-175

Authors: D. Rama Rao *, V. Siddaiah and P.V.S. Machiraju

Soil properties are sensitive to various changes in the management and can be employed as indicators. Pollution in soil and water is strictly related to anthropogenic activities such as industrial wastages. Soil is a vital component, medium of unconsolidated nutrients and materials, forms the life layer of plants. The physico-chemical parameters of soil determine their adaptability to cultivation and the level of biological activity that can be supported by the soil. In view of the applications of chemical fertilizers for higher production of crops, the quality of soil decreases. Keeping in view of the rapid industrialization and hectic agricultural activities in East Godavari region of India, there is great need in analyzing the soils for physico-chemical parameters viz. pH, electrical conductivity, total dissolved solids, total alkalinity, CO3 2–, HCO3 –, OH–, total hardness, Ca2+, Mg2+, Na2+, K+, chloride, sulphate and phosphate to assess the chemical contamination of soils. The correlation matrices for physicochemical parameters are generated to verify the internal relationship between the parameters. Further it is also proposed to estimation of the irrigation parameters viz., percent sodium (Na %), sodium adsorption ratio (SAR), Kelly's ratio (KR) and magnesium hazard (MH) to verify the suitability of soils for irrigation purposes. The results revealed that the soils near sago, paper and sugar industrial areas are slightly alkaline in nature. Higher phosphate concentration indicates the discharge of agriculture runoff in to soils. These irrigation parametric values indicate that these soils suitable for irrigation purposes however higher magnesium hazard (MH) values of soil indicate the depletion of the soil quality which in turn reduce the yield of the crops in study areas.

181-185

Authors: Ekhlas Sheakh Aldeen, Tilal Elsaman *, Malik Suliman Mohamed, Mohamed E. Adam and Magdi Awadalla Mohamed

In the present investigation, 6 compounds (E1-E6) were synthesized by reaction of ethyl esters of p-substituted benzoic acid with hydroxylamine. The chemical structures of the synthesized hydroxamic acids were verified on the basis of spectral analysis (IR, 1H NMR, 13C NMR and mass spectra). The benzohydroxamic acids were examined for potential local anesthetic activity using foot withdrawal reflex of the frog and benzocaine was used as standard drug. Compounds were tested at two different solvents; 5 % DMSO and 0.65 % NaOH, each solution was tested at three different concentration levels (40, 100 and 200 μg/mL). Local anesthetic activity of the compounds differed according to the concentration level and selected solvent. Compounds E4 and E5 were found to be the most active and were comparable to the standard drug in tested solvents at all investigated concentrations. All compounds displayed an enhanced activity in the the aqueous basic solutions

191-198

Authors: L. Devaraj Stephen1, S.G. Gunasekaran1, G. Nalini2 and M. Soundarrajan1,*

Medium imparts changes in redox reactions of metal complexes. That is, solvent plays an important role in trapping the exchanging electron on one site similar to that of intramolecular structural changes. Especially in ionic reactions, ion can be thought of creating a polarization field in the surrounding solvent. The rationality behind the proposal of the kinetics was detailed by fit the data in correlation equation involving linear and multiple Grunwald-Winstein plot, Swain’s dual linear relationship and Kamlet-Taft’s equations. The kinetic inferences of outer-sphere electron transfer reactions of cobalt(III) aryl amine complexes (CoIII(pn)2Cl(L)2+ where L = RC6H5NH2, R = m-OCH3, p-F and H) with MeOH/ dioxane solvent content were explored at different temperatures.

213-219

Authors: Nitin S. Pagar * and Raj M. Deshpande

The hydroformylation of terpenes has been studied with homogeneous Rh, Co and Pt complexes. The rhodium complex, Rh(CO)2(acac) modified with triphenyl phosphite ligand has been found to be the best catalyst system for hydroformylation of camphene and other terpenes. The role of ligands, solvents, Rh:P ratio and reaction conditions on the activity and selectivity towards camphene hydroformylation have been investigated.

229-234

Authors: Mohamad Mirzan, Karna Wijaya *, Iip Izul Falah and Wega Trisunaryanti

Bentonite as a carrier was modified by means of pillarization using ZrOCl2·8H2O pillaring solution. Calcination was performed to obtain ZrO2 bounded bentonite. To create a bifunctional catalyst, ZrO2- bentonite was impregnated using Ni(NO3)2·6H2O precursor as nickel metal source. Subsequently, calcination and reduction steps were performed to obtain Ni/ZrO2-bentonite catalyst. The physicalchemical properties of catalyst was characterized by XRD, XRF and the surface area was analyzed with BET, surface acidity with gravimetric method using NH3 vapour, FT-IR and TEM. The characterized results by XRD showed specific peaks of montmorillonite mineral still visible after the pillarization and impregnation process with nickel metal. The XRD analysis also showed an increase in basal spacing d001 of the catalyst sample after the pillarization process characterized by the shifting of specific peaks d001 to the left (2θ < 5º). The XRF analysis showed that the nickel content in bentonite sample was increased after impregnation with the Ni(NO3)2·6H2O precursor. Qualitatively, acidity of the catalysts was determined by FTIR showing characteristics for Brønsted and Lewis acids at wavenumbers 1635-1381 cm-1. Surface area analysis results showed an increase in specific surface area after pillarization and impregnation with nickel metal.

247-250

Authors: Firas H. Abdulrazzak, Ahmed M. Abbas and Falah H. Hussein*

Multi-walled carbon nanotubes (MWNTs) were synthesized from Iraqis natural gas using flame under carbon monoxide atmosphere. The study focuses on abilities to synthesis and characterization of carbon nanotubes (CNTs) using simple, easy, low cost by natural material. The reactor has been designed for synthesis of carbon nanotubes CNTs from natural gas which acted as a source of carbon in addition to supplying thermal energy instead of electrical energy. Crystallographic and morphological of CNTs have been characterized using powder X-ray diffraction, Raman spectroscopy, transmission electron microscope and thermal gravimetric analysis. The analysis refers to synthesized MWNTs with purity 57.80 % and outer diameter 6.6-17.9 nm, inner diameter 3.2-6.3 nm which equal to 3-9 of graphene layers while the length of tubes is 0.8 to 2 μm.