Good Activity (good + activity)

Distribution by Scientific Domains
Distribution within Chemistry


Selected Abstracts


Bis(phosphinimino)methanides as Ligands in Divalent Samarium Chemistry: Synthesis, Structures and Catalysis

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2007
Michal Wiecko
Abstract The reaction of K{CH(PPh2NSiMe3)2} with samarium diiodide in a 1:1 molar ratio in thf affords the corresponding divalent samarium complex [{(Me3SiNPPh2)2CH}Sm(,-I)(thf)]2 (1), whereas treatment of K{CH(PPh2NSiMe3)2} with samarium diiodide in a 2:1 molar ratio in thf gives the homoleptic complex [{(Me3SiNPPh2)2CH}2Sm] (2). When 1 is treated with KNPh2 in toluene in a 2:1 molar ratio the mixed dimeric compound [({(Me3SiNPPh2)CH}2Sm)2(,-I)(,-NPh2)] (3) is obtained. The single-crystal X-ray structures of all these complexes have been determined. [{(Me3SiNPPh2)2CH}Sm(,-I)(thf)]2 has also been successfully used as a catalyst for the polymerization of ,-caprolactone. Good activities and molecular masses are observed with this catalyst.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


Hydrodenitrification with PdCu Catalysts: Catalyst Optimization by Experimental and Quantum Chemical Approaches

ISRAEL JOURNAL OF CHEMISTRY, Issue 1 2006
Irena Efremenko
A continuous process for nitrate and nitrite abatement from drinking water by catalytic hydrogenation has been developed in our lab. We describe the experimental process development procedure, and support it with semiempirical quantum chemical methods. Comparisons of activated carbon (ACC) and silica glass fiber (GFC) cloths as supports for mono- and bimetallic Pd-Cu catalysts show the former to be 45-fold and 15-fold more active for nitrite and nitrate hydrogenation, respectively, than the latter. Catalysts prepared by selective deposition of Cu on Pd/ACC led to better activity for nitrate hydrogenation than catalysts prepared by co-impregnation or ion exchange methods. The optimal Cu:Pd atomic ratio was found to be 1:2. The computational results show the following: (i) The dispersion of Pd catalysts supported on ACC is much higher than that on GFC due to the larger surface area and higher density of adsorption sites, and that accounts for the higher activity of PdCu/ACC; (ii) Nanosized Pd particles supported on ACC have a semispherical shape and possess preferentially close-packed triangular surfaces, while Pd/GFC particles are extended in the direction parallel to the support surface and show both fcc (100) and (111) planes; (iii) The interaction of Cu atoms with both supports is stronger than that of Pd; adsorbed Cu atoms show a greater ability to form monometallic than bimetallic bonds and that should result in poor mixing of the metal upon co-impregnation, as was observed experimentally; (iv) Cu atoms in bimetallic PdCu particles admit a significant positive charge; the experimentally measured solubility of metal atoms correlates with their calculated charges. The best catalyst (2 wt%Pd-0.6 wt%Cu/ACC) was employed in a novel continuous flow reactor for nitrate hydrogenation in distilled and tap water. The advantages of the reactor investigated over a conventional packed bed reactor are discussed, suggesting a potential for further process intensification. [source]


Effect of certain bioactive plant extracts on clinical isolates of ,-lactamase producing methicillin resistant Staphylococcus aureus

JOURNAL OF BASIC MICROBIOLOGY, Issue 2 2005
Farrukh Aqil
Ethanolic extracts and some fractions from 10 Indian medicinal plants, known for antibacterial activity, were investigated for their ability to inhibit clinical isolates of ,-lactamase producing methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus (MSSA). Synergistic interaction of plant extracts with certain antibiotics was also evaluated. The MRSA test strains were found to be multi-drug resistant and also exhibited high level of resistance to common ,-lactam antibiotics. These strains produced ,-lactamases, which hydrolyze one or other ,-lactam antibiotics, tested. The extract of the plants from Camellia sinensis (leaves), Delonix regia (flowers), Holarrhena antidysenterica (bark), Lawsonia inermis (leaves), Punica granatum (rind), Terminalia chebula (fruits) and Terminalia belerica (fruits) showed a broad-spectrum of antibacterial activity with an inhibition zone size of 11 mm to 27 mm, against all the test bacteria. The extracts from the leaves of Ocimum sanctum showed better activity against the three MRSA strains. On the other hand, extracts from Allium sativum (bulb) and Citrus sinensis (rind) exhibited little or no activity, against MRSA strains. The antibacterial potency of crude extracts was determined in terms of minimum inhibitory concentration (MIC) by the tube dilution method. MIC values, of the plant extracts, ranged from 1.3 to 8.2 mg/ml, against the test bacteria. Further, the extracts from Punica granatum and Delonix regia were fractionated in benzene, acetone and methanol. Antibacterial activity was observed in acetone as well as in the methanol fractions. In vitro synergistic interaction of crude extracts from Camellia sinensis, Lawsonia inermis, Punica granatum, Terminalia chebula and Terminalia belerica was detected with tetracycline. Moreover, the extract from Camellia sinensis also showed synergism with ampicillin. TLC of the above extracts revealed the presence of major phytocompounds, like alkaloids, glycosides, flavonoids, phenols and saponins. TLC-bioautography indicated phenols and flavonoids as major active compounds. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Catalytic synthesis of 1,6-dicarbamate hexane over MgO/ZrO2

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2007
Fang Li
Abstract MgO/ZrO2 catalyst was prepared for the synthesis of 1,6-dicarbamate hexane (HDC) using dimethyl carbonate (DMC) and 1,6-diamine hexane (HDA) as raw materials. When the catalyst is calcined at 600 °C and MgO load is 6 wt%, the catalyst exhibits better activity. When the concentration of catalyst is 2 g (100 mL),1 DMC, n(HDA):n(DMC) = 1:10, reaction time is 6 h under reflux temperature, and the yield of 1,6-dicarbamate hexane is 53.1%. HDC yield decreases from 53.1% to 35.3% after MgO/ZrO2 being used for three times. The decrease in specific surface area may be attributed to deactivation of MgO/ZrO2. Copyright © 2007 Society of Chemical Industry [source]


Synthesis and herbicidal activity of O,O -dialkyl N -[2-(5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidin-2-yloxy)benzoxyl]-1-amino-1-substitutedbenzyl phosphonates

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 1 2010
Wu Tang
A series of novel 1,2,4-triazolo[1,5-a]pyrimidine derivatives containing an ,-amino phosphonate moiety 5 were designed and synthesized by the multi-step reactions. Their structures were clearly confirmed by spectroscopic data (IR, 1H NMR, 31P NMR, MS) and elemental analysis, compound 5b was further determined by X-ray diffraction crystallography. The results of preliminary bioassay indicated that some of the title compounds 5 possessed moderate herbicidal activities against dicotyledonous plants (Brassica campestris L) at the concentration of 100 mg/L. For example, compound 5i possessed 92.0% inhibitory activity against B. campestris L and showed better activity than that of the commercialized herbicide Bispyribac-sodium; however, compounds 5 displayed weak herbicidal activity at the concentration of 10 mg/L. J. Heterocyclic Chem., (2010). [source]


Characterization of glycolipid biosurfactant from Pseudomonas aeruginosa CPCL isolated from petroleum-contaminated soil

LETTERS IN APPLIED MICROBIOLOGY, Issue 1 2010
J. Arutchelvi
Abstract Aims:, To isolate and characterize the biosurfactant-producing micro-organism from petroleum-contaminated soil as well as to determine the biochemical properties of the biosurfactant. Methods and Results:, A novel rhamnolipid-producing Pseudomonas aeruginosa (GenBank accession number GQ241355) strain was isolated from a petroleum-contaminated soil. Surface active compound was separated by solvent extraction of the acidified culture supernatant. The extract was able to reduce the surface tension of water from 72 to 44 mN m,1 at a critical micelle concentration of 11·27 ± 1·85 mg l,1. It showed better activity (based on microdilution method) against Gram-positive (, 31 mg ml,1) bacteria and filamentous fungi (, 50 mg ml,1) than Gram-negative bacteria (, 125 mg ml,1) with mild toxicity (HC50, 38 ± 8·22 ,g ml,1) to red blood cells. Fourier transform infrared spectroscopy revealed the presence of aliphatic chain, hydroxyl groups, ester and glycosidic bonds. Presence of nineteen rhamnolipid homologues with variation in chain length and saturation was revealed from liquid chromatography coupled to mass spectrometry with electrospray ionization. Conclusion:, The results indicate that the isolated biosurfactant has a novel combination of rhamnolipid congeners with unique properties. Significance and Impact of the Study:, This study provides a biosurfactant, which can be used as a biocontrol agent against phytopathogens (Fusarium proliferatum NCIM 1105 and Aspergillus niger NCIM 596) and exploited for biomedical applications. [source]


Synthesis, structural characterization, biological activity and thermal study of tri- and diorganotin(IV) complexes of Schiff base derived from 2-aminomethylbenzimidazole

APPLIED ORGANOMETALLIC CHEMISTRY, Issue 11 2009
Mala Nath
Abstract This report deals with the synthesis and structural features of tri- and diorganotin(IV) complexes of the general formulae, RnSn(L)m [n = 3, m = 1, R = Me, n -Bu and Ph; n = 2, m = 2, R = Me, n -Bu, n -Oct and Ph; HL = Schiff base derived from the condensation of 2-aminomethylbenzimidazole (ambmz) and salicylaldehyde (abbreviated as HL or Hsal-ambmz)]. The newly synthesized complexes were characterized by elemental analysis, molar conductance, electronic, infrared, far-infrared, 1H NMR, 13C NMR, 119Sn NMR and 119Sn Mössbauer spectral studies. Thermal studies of all of the synthesized complexes were also carried out using thermogravimetry,differential thermal analysis-derivative thermogravimetric (TG-DTA-DTG) techniques. The residues thus obtained were characterized by infrared and powder X-ray diffraction analysis. The bioassay results of anti-inflammatory activity (using the carrageenan-induced paw edema bioassay in rats) and acute toxicity (LD50) of the synthesized derivatives indicated that diorganotin(IV) derivatives (19.75,22.23% inhibition) show better activity as compared with triorganotin(IV) derivatives (10.32,17.86% inhibition). Copyright © 2009 John Wiley & Sons, Ltd. [source]


Synthesis of Novel Uracil Non-Nucleoside Derivatives as Potential Reverse Transcriptase Inhibitors of HIV-1

ARCHIV DER PHARMAZIE, Issue 11 2009
Nasser R. El-Brollosy
Abstract Novel emivirine and TNK-651 analogues 5a,d were synthesized by reaction of chloromethyl ethyl ether and / or benzyl chloromethyl ether, respectively, with uracils having 5-ethyl and 6-(4-methylbenzyl) or 6-(3,4-dimethoxybenzyl) substituents. A series of new uracil non-nucleosides substituted at N-1 with cyclopropylmethyloxymethyl 9a,d, 2-phenylethyloxymethyl 9e,h, and 3-phenylprop-1-yloxymethyl 9i,l were prepared on treatment of the corresponding uracils with the appropriate acetals 8a,c. Some of the tested compounds showed good activity against HIV-1 wild type. Among them, 1-cyclopropylmethyloxymethyl-5-ethyl-6-(3,5-dimethylbenzyl)uracil 9c and 5-ethyl-6-(3,5-dimethylbenzyl)-1-(2-phenylethyloxymethyl)uracil 9g showed inhibitory potency equally to emivirine against HIV-1 wild type. Furthermore, compounds 9c and 9g showed marginal better activity against NNRTI resistant mutants than emivirine. [source]


Biosynthesis of New Indigoid Inhibitors of Protein Kinases Using Recombinant Cytochrome P450 2A6

CHEMISTRY & BIODIVERSITY, Issue 1 2005
Zhongliu-Liu Wu
Glycogen synthase kinase-3 (GSK-3) is a potential drug target for a number of human diseases. Some indigoids have been found to be potent inhibitors of GSK-3, and individual compounds with better activity, specificity, and solubility are desired. In this work, a new disubstituted indigoid generation system was developed with a tryptophanase-deficient Escherichia coli strain as a host to express the human cytochrome P450 2A6 mutant L240C/N297Q, which catalyzes the oxidation of indole to isatin and indoxyl, which in turn react to generate indigoids. Forty-five substituted 1H -indoles from commercial sources were used as substrates in the system, and indigoid mixtures were tested as potential inhibitors of GSK-3. After preliminary screening, cell extracts with high inhibitory activity towards GSK-3,/, were fractionated, and the IC50 values of twelve individual indigoids were measured for GSK-3,/, as well as the protein kinases CDK1/cyclinB and CDK5/p25. Several indigoids, including an indigo, showed stronger inhibition than found in previous work. The most potent towards GSK-3,/,, dimethyl indirubin 5,5,-dicarboxylate (IC50 of 51,nM), was modified by chemical reactions. One product, indirubin 5,5,-dicarboxylic acid 5-methyl ester, inhibited GSK-3,/, with an IC50 of 14,nM and selectivity nearly 40-fold over CDK1 and CDK5. Indirubin-5-5,-dicarbonitrile was also modified to the corresponding 3,-oxime, which had low specificity but showed very high inhibition of all three kinases with IC50 values of 5, 13, and 10,nM towards GSK-3,/,, CDK1, and CDK5, respectively. Thus, this system has the potential to generate new indigoids with therapeutic potential. [source]


Catalytic Combustion of Ethyl Acetate over Nanostructure Cobalt Supported ZSM-5 Zeolite Catalysts

CHINESE JOURNAL OF CHEMISTRY, Issue 3 2009
Aligholi NIAEI
Abstract Gas phase catalytic combustion of ethyl acetate, as one of volatile organic compounds (VOC), was studied on nanostructure ZSM-5, HZSM-5 and Co-ZSM-5 with different cobalt loadings. Nanostructure of ZSM-5 was determined by XRD, SEM and TEM. Catalytic studies were carried out under atmospheric pressure in a fixed bed reactor. Results showed that the Co-ZSM-5 catalysts had better activity than others and at temperatures below 350 °C, amount of Co loading was more effective on catalytic activity. The order of conversion of ethyl acetate over different Co loading is as follows: Co-ZSM-5 (0.75 wt%)[source]


Modular Furanoside Phosphite-Phosphoroamidites, a Readily Available Ligand Library for Asymmetric Palladium-Catalyzed Allylic Substitution Reactions.

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2009
Origin of Enantioselectivity
Abstract A library of furanoside phosphite-phosphoroamidite ligands has been synthesized and screened in the palladium-catalyzed allylic substitution reactions of several substrate types. These series of ligands can be prepared efficiently from easily accessible D -xylose and D -glucose. Their modular nature enables the position of the phosphoroamidite group, configuration of C-3 of the furanoside backbone and the substituents/configurations in the biaryl phosphite/phosphoroamidite moieties to be easily and systematically varied. By carefully selecting the ligand components, therefore, high regio- and enantioselectivities (ees up to 98%) and good activities have been achieved in a broad range of mono- and disubstituted hindered and unhindered linear and cyclic substrates. The NMR studies on the palladium-,-allyl intermediates provide a deeper understanding about the effect of the ligand parameters on the origin of enantioselectivity. They also indicate that the nucleophilic attack takes place predominantly at the allylic terminal carbon atom located trans to the phosphoroamidite moiety. [source]


Copolymerization of vinylcyclohexane with ethene and propene using zirconocene catalysts

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 22 2006
Erkki Aitola
Abstract Vinylcyclohexane (VCH) was copolymerized with ethene and propene using methylaluminoxane-activated metallocene catalysts. The catalyst precursor for the ethene copolymerization was rac -ethylenebis(indenyl)ZrCl2 (1). Propene copolymerizations were further studied with Cs -symmetric isopropylidene(cyclopentadienyl)(fluorenyl)ZrCl2 (2), C1 -symmetric ethylene(1-indenyl-2-phenyl-2-fluorenyl)ZrCl2 (3), and "meso"-dimethylsilyl[3-benzylindenyl)(2-methylbenz[e]indenyl)]ZrCl2 (4). Catalyst 1 produced a random ethene,VCH copolymer with very high activity and moderate VCH incorporation. The highest comonomer content in the copolymer was 3.5 mol %. Catalysts 1 and 4 produced poly(propene- co -vinylcyclohexane) with moderate to good activities [up to 4900 and 15,400 kg of polymer/(mol of catalyst × h) for 1 and 4, respectively] under similar reaction conditions but with fairly low comonomer contents (up to 1.0 and 2.0% for 1 and 4, respectively). Catalysts 2 and 3, both bearing a fluorenyl moiety, gave propene,VCH copolymers with only negligible amounts of the comonomer. The homopolymerization of VCH was performed with 1 as a reference, and low-molar-mass isotactic polyvinylcyclohexane with a low activity was obtained. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6569,6574, 2006 [source]


Chemically Induced Cardiomyogenesis of Mouse Embryonic Stem Cells

CHEMBIOCHEM, Issue 2 2010
Albrecht Berkessel Prof. Dr.
Abstract A transgenic murine embryonic stem (ES) cell lineage expressing enhanced green fluorescent protein (EGFP) under the control of ,-myosine heavy chain (,-MHC) promoter (p,-MHC-EGFP) was used to investigate the effects of (thio)urea and cinchona alkaloid derivatives on cardiomyogenesis. The screening of the compounds yielded cardiomyogenesis inducing substances with good (IV-5, V-4) to very good activities (II-16, IV-8), as determined by a 50 to 80,% increase in the EGFP fluorescence compared to untreated cells. Time-dependent screening approaches in which compounds were added at different developmental stages of the ES cells appeared to be of limited suitability for the identification of potential cellular targets. [source]


Synthesis and Biological Activities of Azalamellarins

CHEMISTRY - AN ASIAN JOURNAL, Issue 9 2010
Sasiwadee Boonya-udtayan
Abstract The synthesis of azalamellarins, a new series of lactam analogues of biologically active lamellarins, was achieved using CuI -mediated and microwave-assisted CNamide bond formation. Seventeen azalamellarins, including N -allylazalamellarins and N -propylazalamellarins ,-D, L -N, and J-dehydro J, were synthesized and evaluated for their cytotoxicity against the cancer cell lines HuCCA-1, A-549, HepG2, and MOLT-3. The results showed that certain azalamellarins exhibited good activities in the micromolar IC50 value range (IC50=the drug concentration that causes 50,% of cell-growth inhibition after 72,h of continuous exposure to the test molecule), comparable to their parent lamellarin analogue. [source]


Ruthenium (II) complexes immobilized on swellable polyacrylate matrices: Synthesis and catalytic applications

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2008
Z. S. Liu
Abstract RuH2(PPh3)4 has been immobilized on swellable polyacrylate matrices to provide heterogenized carboxylate-derivatives. These swellable polymer supported ruthenium (II) complex catalysts have been used in the transfer hydrogenation of aldehydes. Hydrogen donors are formate salt, cyclohexanol, and benzyl alcohol. The catalysts exhibit good activity for hydrogen transfer reduction of aldehydes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]


In vitro and in vivo pharmacodynamic properties of the fluoroquinolone ibafloxacin

JOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2002
M. Coulet
The pharmacodynamic properties of a new veterinary fluoroquinolone antimicrobial agent, ibafloxacin, were evaluated. Minimal inhibitory concentrations (MIC), time-kill kinetics, postantibiotic effect (PAE) and postantibiotic subminimal inhibitory concentration effects (PA-SME) were determined against pathogenic canine Gram-negative and Gram-positive bacterial isolates from dermal, respiratory and urinary tract infections. The synergistic interactions between ibafloxacin and its main metabolite, 8-hydroxy-ibafloxacin were investigated. Finally, the efficacy of ibafloxacin was tested in in vivo canine infection models. Ibafloxacin had good activity against Pasteurella spp., Escherichia coli, Klebsiella spp., Proteus spp. and Staphylococcus spp. (MIC90=0.5 µg/mL), moderate activity against Bordetella bronchiseptica, Enterobacter spp. and Enterococcus spp. (MIC50=4 µg/mL) and low activity against Pseudomonas spp. and Streptococcus spp. The time-killing analysis confirmed that ibafloxacin was bactericidal with a broad spectrum of activity. The PAE and PA-SME were between 0.7,2.13 and 1,11.5 h, respectively. Finally, studies in dog models of wound infection and cystitis confirmed the efficacy of once daily oral ibafloxacin at a dosage of 15 mg/kg. Additional studies are needed to better define the importance of AUC/MIC (AUIC) and Cmax/MIC ratios on the outcome of fluoroquinolone therapy in dogs. [source]


Systemic action of novel neonicotinoid insecticide IPP-10 and its effect on the feeding behaviour of Rhopalosiphum padi on wheat

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2010
Li Cui
Abstract BACKGROUND: IPP-10 is a novel neonicotinoid insecticide recently developed in China and has good activity against sucking insects. Studies were carried out to investigate the activity of IPP-10 against Rhopalosiphum padi L. RESULTS: The results demonstrated that IPP-10 had both contact and systemic activity, including acropetal and basipetal translocation in wheat vascular bundles. Starved R. padi were allowed to stay on wheat treated with a sublethal dose of IPP-10. The results of studying their feeding behaviour from an electrical penetration graph (EPG) revealed a decrease in total time and bout duration of xylem and phloem ingestion, but the total time and bout duration of phloem salivation were significantly prolonged. The frequency (7.03 ± 0.49 Hz) of the xylem ingestion waveform produced by aphids on wheat treated with IPP-10 was significantly lower than that of blank control aphids (8.20 ± 0.30 Hz). Consequently, aphids born on wheat treated with IPP-10 were obviously lighter and less fecund than the control aphids. CONCLUSION: These tests indicated that IPP-10 had both contact and systemic activity, with sublethal effects resulting in reduction in R. padi feeding behaviour, growth rate and fecundity. Copyright © 2010 Society of Chemical Industry [source]


Insecticidal activity of N -arylalkylbenzhydrolpiperidines

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 12 2002
Joel M Wierenga
Abstract Benzhydrolpiperidine (BZP) insecticides represent a novel class of chemistry. Their specificity and efficacy as well as their low mammalian toxicity give them excellent potential for commercialization. Several N -arylalkylbenzhydrolpiperidines were tested for activity against a variety of insects in the laboratory and greenhouse. These tests were used to select compounds for field trials and determine rates of application for field tests. The BZP compounds have good activity against Lepidoptera, with modest Coleoptera activity. They are toxic by oral administration and have about 100-fold lower activity by topical exposure. A methyl carbamate BZP, F4265, was the most active compound, with LC50 values of 6,mg,litre,1 or less for most Lepidopteran species tested. F4265 was active in a variety of field trials at 112,224,g,AI,ha,1. Whole-plant testing methods conducted in the greenhouse were effective in determining field test rates. © 2002 Society of Chemical Industry [source]


Antifungal activity of Heterothalamus alienus metabolites

PHYTOTHERAPY RESEARCH, Issue 4 2008
Adriana del V. Pacciaroni
Abstract The chemical study of Heterothalamus alienus gave rutin, spathulenol (1), (1R,7S)-germacra-4(15),5,10(14)-trien-1, -ol (2), sakuranetin (3), padmatin 3-acetate (4), (2R,3R)-dihydroquercetin-7,3,,4,-trimethyl ether (5), (2R,3R)-dihydroquercetin-7,4,-dimethyl ether (6), (2R,3R)-3-acetoxy-5,7,4,-trihydroxyflavanone (7), as the main components of an antifungal extract of the aerial parts of the plant. Compound 2 showed moderate activity, with Epidermophyton floccosum being the most susceptible species (MIC = 100 µg/mL); compound 3 showed the best antifungal behavior having a broad spectrum of action and the lowest MICs. This flavanone along with flavanolol 5 showed very good activity against standardized (MIC = 31.2 µg/mL) as well as clinical isolates of Trichophyton rubrum and T. mentagrophytes (MIC ranges 31.2,62.5 µg/mL and 31.2,125 µg/mL, respectively) and demonstrated not only fungistatic but also fungicide properties. Flavanolol 6 was active against all the dermatophytes tested with MICs of 62.5,250 µg/mL. Rutin, spathulenol (1) and the 3-acetylated flavanones 4 and 7 were inactive or marginally active against the fungal panel. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Antibacterial activity of medicinal plant extracts against periodontopathic bacteria

PHYTOTHERAPY RESEARCH, Issue 6 2003
L. Iauk
Abstract This study was performed to evaluate the antibacterial activity of Althaea of,cinalis L. roots, Arnica montana L. ,owers, Calendula of,cinalis L. ,owers, Hamamelis virginiana L. leaves, Illicium verum Hook. fruits and Melissa of,cinalis L. leaves, against anaerobic and facultative aerobic periodontal bacteria: Porphyromonas gingivalis, Prevotella spp., Fusobacterium nucleatum, Capnocytophaga gingivalis, Veilonella parvula, Eikenella corrodens, Peptostreptococcus micros and Actinomyces odontolyticus. The methanol extracts of H. virginiana and A. montana and, to a lesser extent, A. of,cinalis were shown to possess an inhibiting activity (MIC , 2048 mg/L) against many of the species tested. In comparison, M. of,cinalis and C. of,cinalis extracts had a lower inhibiting activity (MIC , 2048 mg/L) against all the tested species with the exception of Prevotella sp. Illicium verum methanol extract was not very active though it had a particular good activity against E. corrodens. The results suggest the use of the alcohol extracts of H. virginiana, A. montana and A. of,cinalis for topical medications in periodontal prophylactics. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Photooxidations of phenol, cyclopentadiene and citronellol with photosensitizers ionically bound at a polymeric ion exchanger,

POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 3-4 2001
Robert Gerdes
Abstract Different metal tetrasulfophthalocyanines and rose bengal were employed as photosensitizers in the photooxidation of phenol, cyclopentadiene and (S)-(,)-citronellol. Ionically polymer bound photosensitizers were easily obtained by the reaction of negatively charged low-molecular-weight phthalocyanines with the strong basic anion exchanger Amberlite® IRA 400. The activities of the low-molecular-weight and the polymer systems are compared. Especially immobilized phthalocyanines which exhibit the advantages of good activity, as well as stability against photobleaching, and can be used repeatedly. Copyright © 2001 John Wiley & Sons, Ltd. [source]


In-vitro antimicrobial, thermal and spectral studies of mixed ligand Cu(II) heterochelates of clioquinol and coumarin derivatives

APPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2010
G. J. Kharadi
Abstract The mixed-ligand heterochelates of Cu(II) with 5-chloro-7-iodo-8-hydroxyquinoline (clioquinol) and various uninegative bidentate ligands were prepared. The structure of mixed-ligand heterochelates was investigated using spectral, physicochemical, elemental analysis and thermal studies. The FAB-mass spectrum of [Cu(A2)(CQ)(H2O)2].2H2O has been carried out. Magnetic moment and reflectance spectral studies reveal that an octahedral geometry has been assigned to all the prepared heterochelates. The kinetic parameters such as order of reaction (n), the energy of activation (Ea), the pre-exponential factor (A), the activation entropy (,S#), the activation enthalpy (,H#) and the free energy of activation (,G#) have been reported. The ligands, metal salts, heterochelates, control and standard drug were tested for their in-vitro antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens and Bacillus substilis. The metal complexes exhibit good activity against bacterial strains compared with parental compounds, and moderate compared with the standard drug (clioquinol). Copyright © 2010 John Wiley & Sons, Ltd. [source]


Preparation and catalytic properties of bis(imino)pyridine palladium(II) complexes as efficient catalysts for Suzuki cross-coupling reaction in water

APPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2009
Ping Liu
Abstract Air-stable bis(imino)pyridine palladium(II) complexes were synthesized and complex 12 proved to be a highly efficient catalyst for the Suzuki cross-coupling reaction between aryl bromides and arylboronic acids in air using water as solvent. The coupling reaction proceeded smoothly under mild conditions to provide biaryls in excellent yields and Pd black was not observed. The recycling of the catalysts was also investigated, for up to three cycles, and complex 12 still exhibited good activity. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Synthesis of Novel Uracil Non-Nucleoside Derivatives as Potential Reverse Transcriptase Inhibitors of HIV-1

ARCHIV DER PHARMAZIE, Issue 11 2009
Nasser R. El-Brollosy
Abstract Novel emivirine and TNK-651 analogues 5a,d were synthesized by reaction of chloromethyl ethyl ether and / or benzyl chloromethyl ether, respectively, with uracils having 5-ethyl and 6-(4-methylbenzyl) or 6-(3,4-dimethoxybenzyl) substituents. A series of new uracil non-nucleosides substituted at N-1 with cyclopropylmethyloxymethyl 9a,d, 2-phenylethyloxymethyl 9e,h, and 3-phenylprop-1-yloxymethyl 9i,l were prepared on treatment of the corresponding uracils with the appropriate acetals 8a,c. Some of the tested compounds showed good activity against HIV-1 wild type. Among them, 1-cyclopropylmethyloxymethyl-5-ethyl-6-(3,5-dimethylbenzyl)uracil 9c and 5-ethyl-6-(3,5-dimethylbenzyl)-1-(2-phenylethyloxymethyl)uracil 9g showed inhibitory potency equally to emivirine against HIV-1 wild type. Furthermore, compounds 9c and 9g showed marginal better activity against NNRTI resistant mutants than emivirine. [source]


Cloning, recombinant production, crystallization and preliminary X-ray diffraction analysis of a family 101 glycoside hydrolase from Streptococcus pneumoniae

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 2 2009
Katie J. Gregg
Streptococcus pneumoniae is a serious human pathogen that is responsible for a wide range of diseases including pneumonia, meningitis, septicaemia and otitis media. The full virulence of this bacterium is reliant on carbohydrate processing and metabolism, as revealed by biochemical and genetic studies. One carbohydrate-processing enzyme is a family 101 glycoside hydrolase (SpGH101) that is responsible for catalyzing the liberation of galactosyl ,1,3- N -acetyl- d -galactosamine (Gal,1,3GalNAc) ,-linked to serine or threonine residues of mucin-type glycoproteins. The 124,kDa catalytic module of this enzyme (SpGH101CM) was cloned and overproduced in Escherichia coli and purified. Crystals were obtained in space group P21 and diffracted to 2.0,Å resolution, with unit-cell parameters a = 81.86, b = 88.91, c = 88.77,Å, , = 112.46°. SpGH101CM also qualitatively displayed good activity towards the synthetic substrate p -nitrophenyl-2-acetamido-2-deoxy-3- O -(,- d -galactopyranosyl)-,- d -galactopyranoside, which is consistent with the classification of this enzyme as an endo-,- N- acetylgalactosaminidase. [source]


Synthesis, Cytotoxicity and Antileishmanial Activity of Some N -(2-(indol-3-yl)ethyl)-7-chloroquinolin-4-amines

CHEMICAL BIOLOGY & DRUG DESIGN, Issue 6 2010
Elaine S. Coimbra
We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3). Hydrolysis of the methyl ester adduct (5) yielded the free acid (6). The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells. [source]