Asian Journal of Chemistry

1895-1898

Authors: Relangi Siva Subrahmanyam and Venkateswara Rao Anna

We report here an easy, efficient and green synthetic protocol forthe (E)-1-aryl-3-(2-morpholinoquinolin3-yl)prop-2-en-1-ones by the Claisen-Schmidt condensation of 2-morpholinoquinoline-3-carbaldehyde and different substituted acetophenones by using 1-butyl-3-methylimidazolium tetrafluoroborate (Bmim)BF4. The compounds were characterized by using 1 H NMR, 13C NMR and mass spectral data and screened there in vitro antimicrobial activity against different bacterial and fungal organismsClaisen-Schmidt condensation, Ionic liquid, Chalcone, Quinoline, Antimicrobial activity

1905-1912

Authors: Kummara Srinivasulu , Katreddi Hussain Reddy, K. Anuja , D. Dhanalakshmi and Golla Ramesh

Metal complexes having the composition M(Bipy)Cl2 (where, M = Cu(II), Ni(II) and Co(II); Bipy = 2,2-bipyridyl) are reacted with 2-acetylthiophene thiosemicarbazone (ATT) to produce heteroleptic transition metal complexes with molecular formula [M(Bipy)ATT]. The complexes are characterized by mass spectra, molar conductivity, infrared and electronic spectra. Electrochemical behaviour of these metal complexes was investigated by cyclic voltammetric studies. The metal complexes show quasi reversible cyclic voltammetric responses for the Cu(II)/Cu(I) couple. The binding properties of these complexes with calf-thymus DNA have been investigated by using absorption spectrophotometry. Metal complexes are screened for their antibacterial activity by using agar well diffusion method against pathogenic bacterial strains viz. Escherichia coli and Staphylococcus aureus. Antibacterial activity of the present complexes are comparable with the activity of ciprofloxacin. The Cu(Bipy)Cl2 complex inhibits bacteria more strongly than any other complex. The Ni(Bipy)ATT complex shows more activity than the parent complex, Ni(Bipy)Cl2.

1919-1925

Authors: H.B. Kruthi, H. Shreya, Ch. Mahendra , R.R. Siva Kiran and Archna

The feasibility of saw palmetto fruit (Serenoa repens) waste as a low-cost bio-sorbent for treating methylene blue dye from synthetic textile effluent was evaluated. Two different types viz., untreated and alkaline treated saw palmetto fruit waste was tested to immobilize methylene blue dye from the synthetic effluent solution. Out of these two, the only alkaline treated saw palmetto fruit waste was found suitable for the removal of methylene blue from aqueous streams. With the untreated saw palmetto fruit waste, the sorption of dye increased with time and after reaching equilibrium, back diffusion of the sorbed dye was observed. Equilibrium sorption and kinetic studies were performed with alkaline treated saw palmetto fruit waste and the parameters affecting the sorption process such as initial dye concentration, adsorbent dose, equilibrium time and temperature were analyzed. The kinetic data generated obeyed pseudo-second-order kinetics. The investigated removal capacity of the saw palmetto fruit waste for the methylene blue dye was comparable with the available sorbents

1931-1942

Authors: R. Suganthi Devi and N. Kumaraguru

The interaction of ligand bound ruthenium(II) complexes with DNA have grown fame because of their relevance in the development of new reagents for medicinal applications and the impact of dominating cisplatin. Surfactant-ruthenium(II) complexes [Ru(DMP)2(DA)Cl](ClO4) (1) and [Ru(DMP)2(DA)2](ClO4)2 (2) with primary ligand as DMP (2,9-dimethyl[1,10]-phenanthroline) and secondary ligand as dodecyl amine (DA) were synthesized and characterized. The critical micelle concentration (CMC) of complexes in aqueous solution were obtained from conductivity measurements. The interaction of surfactant-ruthenium(II) complexes with CT-DNA has been explored by spectroscopic technique and viscosity dimensions. These complexes were tested for cytotoxic and antimicrobial activities with human cervical cancer cell line (HeLa) and pathogenic microorganisms. The results indicate that the complex 2 binds more strongly to DNA than complex 1 further affecting the viability of the cells significantly and also showed moderate antimicrobial activity

1949-1958

Authors: Poonam Mishra Chatterjee, Deepika Pandey Tiwari, Silpi Datta , Suman Chakrabarty , Ritu Raval and Ashok Kumar Dubey

Polyglutamic acid (PGA) is an anionic biopolymer which is stained with methylene blue (MB) in agar or polyacrylamide gels for analysis. Polyglutamic acid identification involves a tedious extraction and analytical process. The molecular association of polyglutamic acid and methylene blue can be used for rapid spectroscopic detection of polyglutamic acid production during fermentation. This triggered the study on investigation of polymer-dye interaction mechanism. Concentration range of polyglutamic acid, 0.001 to 0.06 µM with a fixed methylene blue concentration of 25 µM exhibited significant differences in the spectra. Preferential higher order aggregate formation of methylene blue molecules was substantiated with molecular dynamics simulation results. Fluorescence spectroscopy demonstrated a quenching effect of polyglutamic acid on methylene blue fluorescence until a certain concentration range, beyond which the Stern-Volmer (SV) plot shows a negative deviation. Polyglutamic acid was observed to promote higher order of intramolecular stacking interactions of methylene blue, possibly due to interplay of electrostatic and hydrophobic interactions between polyglutamic acid, methylene blue alone and PGA-MB systems.

1966-1970

Authors: R. Arunkumar and D. Benny Anburaj

A single crystal of L-valine piperazinium was grown by slow growth technique. Structural studies confirm the monoclinic structure with space group P21. The solubility curve showing high soluble in water and peak shows positive solubility nature. A tiny nucleation formed at 10 ºC for room temperature process and it gradually increasing with respect process temperature. Induction period revels that time period for nucleation at constant temperature and it absorbed that in (10 ºC) 500 s for room temperature. The calculated interfacial tension values are greater than one order other amino acid based piperazinium. By using growth parameters bulk L-valine piperazinium crystal were harvested and single crystal XRD confirms that formation of L-valine piperazinium crystals

1979-1984

Authors: B. Roopashree and V. Gayathri

CuX2·6H2O (X = Cl– , Br– or ClO4 – ) reacted with a Schiff base ligand 2-[(3′-N-salicylidinephenyl)benzimidazole] in 1:2 mole ratio in methanol to yield brown colored complexes of types [CuCl2L]2, [CuBr1.5L1.5]2Br and [Cu(OClO3)L2]2(ClO4)2·4H2O. The complexes were characterized by analytical and spectroscopic studies such as elemental analysis, conductivity and magnetic moment measurements, thermogravimetric analysis, IR, far-IR, electronic, ESR and mass spectral studies. IR spectral studies suggested the coordination of ligand to the central metal atom via tertiary nitrogen of benzimidazole and nitrogen of azomethine group. Based on these studies, binuclear structure was proposed for all the copper complexes. The ligand and its copper(II) complexes were screened for antibacterial and antifungal activities

1989-1992

Authors: Neha Singh, Richa Khare and Krishna Srivastava

A differentiated series of thiocarbonic acid esters have been synthesized and characterized in good to excellent yields with the help of thiols, carbon di sulphide and alkyl/aryl halides in DMSO with benzyl trimethylammonium hydroxide where Triton B acts as a catalyst. This method is safer and efficient as compared to other conventional methods.

2000-2008

Authors: Kishore D. Deo , I.J. Singhvi , S.R. Patil and Avinash V. Patil

A series of novel diketoquinoline acid derivatives as potential anti-HIV-1 Integrase inhibitors were docked, synthesized and characterized by IR, NMR , CHN and MS spectral analysis. Many compounds were identified and docked in integrase pocket. The target diketoquinolines were prepared from substituted oxoquinoline-3-carboxylate. In vitro biological evaluation revealed that some of the titled compounds exhibited moderate to good anti-HIV-1 Integrase inhibitory activity in comparison with the reference drugs i.e. raltegravir and nevirapine. The cytotoxicity of most of testing compounds on C8166 were very low, the CC50 value of them were higher than 200 µM, except the few compounds. Compounds 1-5 showed weak anti-HIV-1 activity, its therapeutic index was 457, 531, 583, 869 and 909 respectively. As a positive control drug, Nevirapine has the best anti-HIV-1 activity (EC50 = 0.015-0.016 µM) in vitro and the CC50 of was higher than 200 µM, its therapeutic index was higher 12418.50. In integrase assay compound 6 and 7 showed EC50 value 0.08 µM as compared with standard drug raltegravir.

2015-2021

Authors: Ashok K. Singh1,*, Suresh K. Patel1, and Asif Jafri

A series of eight Co(III) complexes [CoL1-8(H2O)2Cl] (I-1 to I-8) incorporating 4-(2-substituted phenylimino)-2-(4-substituted phenyl)-4H-chromen-3-ol, as a tridentate imino flavone ligands (L1 to L8, 2-sub. = NH2, SH, 4-sub. = OMe, OH, Cl, NMe2) have been synthesized, characterized and the geometry of the complexes were optimized by DFT. The chemical structure of synthesized imino flavone ligands and their complexes were characterized by elemental analysis, 1 H NMR, 13C NMR, UV-visible, IR, ESI-mass spectral data, conductometric and magnetic measurements. The synthesized compounds have been screened for their in vitro antibacterial activities against bacteria Vibrio cholerae, Salmonella typhi, Staphylococcus aureus, Escherichia coli and antifungal activities against fungi Candida albicans and Aspergillus flavus by paper disc diffusion method. The complexes I-3, I-4, I-7 and I-8 showed good antimicrobial activities against pathogens.

2037-2041

Authors: M. Reddeppa , R. Chenna Krishna Reddy, P. R. Sougandhi , S.S. Harini and T. Shobha Rani

Plant mediated green synthesis of silver nanoparticles (AgNPs) was carried out with the plant extract of Vitex negundo Linn., a simple method without using harmful chemicals. Herein, a root bark extract is used as reducing and capping agent for synthesizing AgNPs from silver nitrate solution. The characterization of AgNPs were obtained by UV-visible spectrophotometer, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and energy dispersive spectroscopy. The results were confirmed the presence of silver nanoparticles with UV-visible absorption peak at around 433-443 nm and its crystalline nature by XRD analysis. The FTIR spectrum confirmed that the synthesized AgNPs are stabilized and protected by various functional groups of biomolecules in extract. The SEM morphology showed the triangular or spherical shape of AgNPs with the size in the range of 80-100 nm and EDS confirmed the presence of elemental silver in the sample. The catalytic activity of AgNPs was investigated in the synthesis of 5-substituted 1H-tetrazole. Furthermore, antibacterial profile showed that biopotent AgNPs exhibited moderate to good antibacterial activity.

2047-2056

Authors: Shashi Kant Sharma* , Nisha Sharma and Poonam Thakur

A comparative study of complexation behaviour of three tetracycline derivatives viz. doxycycline hydrochloride, oxytetracycline hydrochloride and minocycline hydrochloride with β-cyclodextrin (β-CD) has been done with the help of various thermodynamic and spectroscopic methods. Density (ρ) and conductivity measurements have been carried out for binary drug/water and ternary drug/water/(β-CD) systems at three different temperature viz. 305.15, 310.15 and 315.15 K. The interactions of these tetracycline derivatives with β-cyclodextrin in aqueous solutions are further studied by means of fluorescence spectroscopy and UV-visible spectroscopy. From the measured density (ρ) data, partial molar volume (Φ° ν), partial molar volume expansibility (ϕ°e), Hepler′s constant (∂2 ϕ° ν / ∂T2 )P and partial molar volume of transfer (∆ϕ°ν) have been obtained. From the conductance studies, the energetically favourable interactions are interpreted in the form of free energy change (∆G) and the apparent association constant (Ka) was estimated from the fluorescence data

2065-2068

Authors: P. Nautiyal, K.A. Subramanian, M.G. Dastidar and A. Kumar

Currently, biodiesel produced from algae is receiving a positive response as a substitute for conventional base diesel. To cope up from the costs of expensive downstream stages in the production of biodiesel from algae, present investigation is conducted using algae growing in wastewater as lipid source for biodiesel production. The in situ transesterification using algae was carried to optimize the effect of reaction parameters on the biodiesel yield. The parameters studied were: temperature (35-75 ºC), algae biomass (wt.) to methanol (vol.) ratio (1:1-1:6), catalyst concentration (25-100 wt. %) and stirring intensity (150-750 rpm). The optimum conditions for maximum biodiesel yield achieved were: catalyst concentration and algae biomass to methanol ratio were 60 % and 1:4, respectively with stirring intensity of 450 rpm at 55 ºC. The gas chromatographic studies and fuel properties of biodiesel also establish its potential to be used as fuel in existing engines in accordance to American and European standards

2073-2082

Authors: Eman Alzahrani

Boronate affinity chromatography (BAC) is argued to be a critical tool in specific capture and separation of cis-diol containing compounds. In present study, organic boronate affinity monolith poly(3-acrylamido phenylboronic acid-co-ethylene dimethacrylate) (AAPBA-co-EDMA) is prepared through one-step in situ polymerization procedure within a micropipette through the application of a pre-polymerization mixture which contains functional monomer (3-acrylamido phenylboronic acid), cross-linker (ethylene dimethacrylate), porogenic solvent (methanol with poly ethylene glycol) and initiator (2,2-dimethoxy-2-phenyl-acetophenone). Following the optimization of time exposure to UV lamp with 365 nm, the macroporous organic boronate monolith was selected. Several approaches including SEM and BET analysis, FT-IR spectroscopy and measuring contact angle were applied in the characterization of the morphology of the monolith. Several cis-diol compounds that include catechol and galactose are applied in the assessment of the boronate affinity of the organic monolithic material. Additionally, the capture of glucose from urine sample is also conducted. The basic principle of the approach is that boronic acid forms covalent bond with cis-diols in basic solutions whereas the ester bonds are dissociated under acidic media. By using the study results, monolith demonstrate good selectivity towards cis-diol containing compounds. Due to the hydrophilic property of monolith, the affinity chromatography monolith can be performed for several cis-diol compounds including glycoproteins and nucleosides. Also, fabrication of the organic boronate monolithic in microfluidic equipment is essential in facilitating the extraction of boronate affinity using small-volume samples.

2087-2090

Authors: P.K. Gupta, Dinesh Kumar and Amit Kumar

Novel polystyrene supported mixed Schiff base (PSCH2–LH2) and its coordination compounds with copper(II) and zirconium(IV) have been synthesized. PSCH2–LH2 has been synthesized by the reaction of chloromethylated polystyrene crosslinked with divinylbenzene (PSCH2–Cl) and the Schiff base (LH2) derived from 3-formylsalicylic acid, propylenediamine and acetylacetone. The polystyrene supported coordination compounds are of the types: [PSCH2–LCu] and [PSCH2–LZr(OH)2·DMF]. They have been synthesized by the reaction of PSCH2–LH2 and the metal salt in DMF. The coordination compounds have been characterized on the basis of elemental analyses, IR, reflectance, ESR spectral and magnetic susceptibility measurements. The shifts of the ν(C=N) (azomethine), ν(C–O) (phenolic) and ν(C–O) (enolic) stretches indicate the ONNO donor behaviour of PSCH2–LH2. The polystyrene supported Cu(II) compound is square planar and Zr(IV) compound is pentagonal bipyramidal. The coordinated solvent molecules are completely lost from metal bound coordination compound by heating them at definite temperature in an air oven for 3 h. The compound, PSCH2–LCu is paramagnetic, while PSCH2–LZr(OH)2·DMF is diamagnetic

2095-2100

Authors: P. Priya, S. Vedanayaki and P. Jayaseelan

A new Schiff base ligand (L) N-(4-fluorophenyl)-1-(4-(((4-fluorophenyl)imino)methyl)phenyl)- methaninmine was prepared by the condensation of terephthalaldehyde with 4-fluoroaniline in 1:2 molar ratio. The mononuclear complexes of Co(II), Ni(II), Cu(II) and Zn(II) (1-4) have been synthesized in (2:1) ligand to metal ratio. The composition, geometry and binding sites of ligand with metal complexes were evidenced by various spectral methods like molar conductance, elemental analytical data, magnetic measurements, UV-visible, 1H & 13C NMR, ESI-MS, FT-IR, ESR and thermal analysis. The above studies shows that the ligand is a bidentate and its metal complexes possess an octahedral geometry. Oxidative cleavage of DNA studies of the complexes were monitored by super helix PUC18DNA using a method of agarose gel electrophoresis. Ligand and its metal complexes were screened against gram positive (Staphylococcus aureus), gram negative (Klebsiella pneumoniae) bacterium and fungus (Candida albicans) strains. Antioxidant activities of the metal complexes possess greater activity than ligand.

2107-2110

Authors: Kousuke Iwasaki, Yamazaki Yudai and Hiroaki Gotoh

Organocatalysts have been the subject of intense research effort because of their low toxicity, facile handling, and eco-friendly characteristics. Recently, the development of C-H activation reaction using organocatalysts has also been studied. Herein, we report the studies on the oxidative coupling of 9,10-dihydroacridine and nitromethane using a series of stable radicals. tert-Butyl(10-phenyl-9- anthryl)nitroxide was found to be an optimal catalyst for the coupling reaction

2116-2120

Authors: Vinod Kumar Vashistha, Neeraj Sharma, Anuj Kumar and Usha Rani Sharma

Hexamethyldibenzotetraaza[14]annulene type macrocyclic complexes of Ni(II) and Cu(II) have been synthesized by template method. These macrocyclic complexes were characterized by molar conductance, elemental analysis, IR, UV-visible, mass spectra and cyclic voltammetry. On the basis of electronic studies saddle shape distorted octahedral structure have been assigned to these macrocyclic complexes. The redox behaviour of Ni(II) and Cu(II) macrocyclic complexes showed reversible and quasi-irreversible redox process that supported by the ipc/ipa ratio which is in good agreement with Randles-Sevcik equation. These macrocyclic complexes were also studied for the antimicrobial activity against E. coli, P. aeruginosa, B. subtilis, S. aureus and C. albicans compared with gentamycin as standard drug

2125-2132

Authors: Xuan Bui Thi , Loi Vu Duc, Tung Bui Thanh and Ngoc Tran Minh

Five compounds (1-5) were isolated from the leaves of Sanchezia nobilis collected in Nam Dinh province by chromatographic methods. These compounds were identified as: mangiferin (1), β-sitosterol (2), margaric acid (3), ursolic acid (4), oleanolic acid (5). Their structures were elucidated by spectroscopic methods, including mass spectrometry and nuclear magnetic resonance. These compounds were isolated from the leaves of Sanchezia nobilis for the first time. Screening of gastric and duodenal antiulcer effects on indomethacin induced gastric ulcer models showed that n-hexane fraction produced the highest antiulcer activity. Percentage inhibition of gastric ulceration of misoprostol was 22.86 %, while that of n-hexane fraction was 28.57 % (p < 0.05). Evaluation of gastric and duodenal antiulcer effects on acysteamine induced gastric ulcer models showed that this fraction was effective against gastric and duodenal ulcer (83.3 %), improved ulcer damage (54.17 %), significantly reduced the number of mean ulcer and ulcer index (2.00 ± 1.28) but it did not change the area of the ulcer.