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Derived
Kinds of Derived Selected AbstractsPossibilism: An Approach to Problem-Solving Derived from the Life and Work of Albert O. HirschmanDEVELOPMENT AND CHANGE, Issue 3 2008Philipp H. Lepenies ABSTRACT Albert O. Hirschman is the author of seminal, but prima facie unconnected contributions to the social sciences (,exit,voice', ,linkages'). Yet, his main originality lies in his general approach to problem-solving which is hidden behind the complexity of his oeuvre. This article intends to disentangle the intricacies of his work and to reveal his specific mode of investigation by making the multifaceted biographical influences on Hirschman's scholarly writings visible. Exhibiting the influence that decisive moments in his life had on his work not only allows us to identify and define his method of ,possibilism': it also shows that this approach remains a valid and useful multidisciplinary tool for unorthodox contemporary social analysis. [source] Tricarbonyl Rhenium(I) and Technetium(I) Complexes with Hydrazones Derived from 4,5-Diazafluoren-9-one and 1,10-Phenanthroline-5,6-dioneEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 29 2010Paula Barbazán Abstract Tricarbonylrhenium(I) and -technetium(I) halide (halide = Cl and Br) complexes of ligands derived from 4,5-diazafluoren-9-one (df) and 1,10-phenanthroline-5,6-dione (phen) derivatives of benzoic and 2-hydroxybenzoic acid hydrazides have been prepared. The complexes have been characterized by elemental analysis, MS, IR, 1H NMR and absorption and emission UV/Vis spectroscopic methods. The metal centres (ReI and TcI) are coordinated through the nitrogen imine atoms and establish five-membered chelate rings, whereas the hydrazone groups stand uncoordinated. The 1H NMR spectra suggest the same behaviour in solution on the basis of only marginal variations in the chemical shifts of the hydrazine protons. [source] Synthesis and Crystal Structure of a Heptanuclear and an Octanuclear Copper(II) Complex Derived from ,- D -GlucofuranosesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2007Michael Gottschaldt Abstract CuII complexes of different 6-(,-keto-enamino)-6-deoxy-1,2- O -isopropylidene-,- D -glucofuranoses 3a,f have a high tendency to build up oligonuclear clusters. Two new oligonuclear copper(II) complexes could be synthesised, crystallised and their structures determined. The complex Cu(3a) was found to consist of a heptanuclear cluster in which two ,-cubane like substructures share one copper ion. The structure is highly asymmetric and in the cluster every CuII ion has a different coordination geometry. Variation of the residues of the ,-ketoenaminic unit leads to the formation of the octanuclear copper(II) complex Cu(3e). Similarly, this has two ,-cubane subunits consisting of a heptanuclear structure with an additionally attached copper ion. In the crystal, two Cu8 cluster molecules are found differing in their geometries due to intermolecular interactions responsible for the formation of a supramolecular network. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] N -Allylideneamines Derived from Acrolein: Synthesis and Use as Acceptors of Two NucleophilesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2009Isao Mizota Abstract Two practical methods have been developed for the preparation of N -allylideneamines 1b,c. One involves the isomerization of propargylamines and the other the dehydration of acrolein. N -Allylideneamines 1b,c thus prepared were used as efficient substrates for 1,4- and 1,2-double nucleophilic addition reactions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Preparation and Transmetallation of Enantioenriched ,-Aminoorganostannanes Derived from N -Boc Phenylglycinol: Application to the Synthesis of AlafosfalinEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 19 2008Vincent Coeffard Abstract Enantioenriched tributylstannylated ,-amino alcohols were synthesised by an improved procedure based on ring opening of 2-tributylstannyloxazolidines. Corresponding ,-amino organolithiums were generated from O -silylated tributylstannylated ,-amino alcohols and trapped with retention of configuration. Thereby, this methodology was used to synthesise the antibacterial ,-aminophosphonic acid alafosfalin.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Syntheses of O6 -Alkyl- and Arylguanine Derivatives: Nucleobase Adducts Derived from Styrene 7,8- and 3,4-OxidesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 2 2006Jan Novák Abstract A series of O6 -alkyl and -arylguanine derivatives that may be formed in vivo after exposure to styrene has been prepared by reaction of 6-(4-aza-1-azoniabicyclo[2.2.2]octyl)-purine with alkoxides and aryloxides, respectively. Themonoprotected diols 2-allyloxy- or 2-benzyloxy-1-phenylethanol and 2-allyloxy- or 2-benzyloxy-2-phenylethanol were used as synthetic equivalents of styrene 7,8-oxide. 4-Vinylphenol, 2-(4-hydroxyphenyl)ethanol and 4-hydroxyphenylacetic acid were used as synthetic equivalents of arene oxide metabolites of styrene, i.,e., styrene 3,4-oxide, 4-(2-hydroxyethyl)benzene 1,2-oxide and 4-carboxymethylbenzene 1,2-oxide, respectively. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Synthesis and Rearrangement of N -Organyloxy ,-Lactams Derived from a (4+2)/(3+2) Sequential Cycloaddition Reaction Involving Enol Ethers and Nitro AlkenesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 21 2004Leon W. A. van Berkom Abstract The synthesis of N -organyloxy ,-lactams 2 by treatment of nitroso acetals 1 with a base is discussed. Based on the formation of a by-product, a mechanism for the rearrangement to N -organyloxy ,-lactams is proposed. This mechanism is supported by trapping of the intermediate acyl nitro compound 8 with dimethylamine. Furthermore, it was discovered that upon more forcing basic conditions these N -organyloxy ,-lactams can rearrange further to 3-organyloxy ,-lactams. By using a series of structurally diverse N -organyloxy ,-lactams the generality of this novel rearrangement is demonstrated. A mechanism for the conversion of N -organyloxy ,-lactams to 3-organyloxy ,-lactams is proposed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Novel Cyclic 1,2-Diacetals Derived from (2R,3R)-(+)-Tartaric Acid: Synthesis and Application as N,O Ligands for the Enantioselective Alkylation of Benzaldehyde by DiethylzincEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 8 2004M. Teresa Barros Abstract A chiral cyclic 1,2-diacetal derived from tartaric acid was used as the basic structural unit for novel ligands. Monooxazoline carbinols in which the degree of substitution of the alcohol and the nature of the stereocentre in the oxazoline ring were varied were synthesized in moderate to good yields. The influence of these structural factors on asymmetric induction was examined in the enantioselective addition of diethylzinc to benzaldehyde. Up to 60% ee was observed with a secondary or a tertiary alcohol as the metal-chelating group. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Synthesis of Enantiopure 1-Aryl-1-butylamines and 1-Aryl-3-butenylamines by Diastereoselective Addition of Allylzinc Bromide to Imines Derived from (R)-Phenylglycine AmideEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 7 2004Jan Dalmolen Abstract The synthesis of enantiopure 1-aryl-1-butylamines via a highly diastereoselective addition of allylzinc bromide to imines derived from (R)-phenylglycine amide is reported. These are synthesised by a three-step procedure, which involves: (a) formation of the chiral imines; (b) asymmetric addition of the allylzinc reagent; (c) removal of the chiral auxiliary by means of a reductive or non-reductive method. The reductive method provides 1-aryl-1-butylamines whereas the non-reductive method preserves the double bond to afford 1-aryl-3-butenylamines. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Radical Cation and Dication Derived from 4,8-Diethylbenzo[1,2- d:4,5- d,]bis[1,2,3]trithiole [DEBBT]: Change of Electronic State from Singlet-State Dication DEBBT(2+)- S to Triplet-State Dimer 2DEBBT(2+)- T in D2SO4 and CD3CN SolutionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2003Takeshi Kimura Abstract 4,8-Diethylbenzo[1,2- d:4,5- d,]bis[1,2,3]trithiole [DEBBT] was oxidized using concentrated D2SO4, leading to the generation of the radical cation DEBBT(·+) which was verified by ESR spectroscopy. DEBBT(·+) in the solution was further oxidized to produce the dication DEBBT(2+), as determined by 1H and 13C NMR spectroscopy. DEBBT(2+) was also prepared by treating DEBBT 1-oxide [DEBBT 1-O] with concentrated D2SO4, and was verified by 1H and 13C NMR spectroscopy. The 13C NMR chemical shifts of DEBBT(2+), calculated by the density functional theoretical (DFT) method at the B3LYP6-31G** level, correlated well with those obtained experimentally. The ESR signal of DEBBT(2+) generated from DEBBT 1-O was observed in solution, which implies that the singlet-state dication DEBBT(2+)- S isomerizes to the triplet-state dication DEBBT(2+)- T, and that two molecules of DEBBT(2+)- T further form a spin pair at one trithiole ring with significant distance between the two radical centers. The oxidation of DEBBT with one or two equivalents of single-electron oxidizing reagents produced DEBBT(·+) and DEBBT(2+), and the salts were isolated in a stable form. However, the DEBBT(2+) that was prepared by oxidation with NOPF6 proved silent for NMR in CD3CN, while ESR was active. The stability, electronic state, and NMR and ESR spectroscopy of the dication are affected by solvation with D2SO4 and CD3CN. The optimized structures and the total energy of the singlet- and triplet-state dication were calculated using the DFT method at the B3LYP6-31G** level, which shows that the structures of the singlet- and triplet-state dications have a completely planar form with 1.7 kcal/mol as the total energy difference between them. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Biomimetic Composites: Protein Localization in Silica Nanospheres Derived via Biomimetic Mineralization (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 18 2010Mater. Abstract Lysozyme-templated precipitation of silica synthesized by sol-gel chemistry produces a composite material with antimicrobial properties. This study investigates the structural properties of the composite material that allow for retention of the antimicrobial activity of lysozyme. Scanning (SEM) and transmission (TEM) electron microscopy reveal that the composite has a hierarchical structure composed of quasi-spherical structures (,450 nm diameter), which are in turn composed of closely packed spherical structures of ,8,10 nm in diameter. Using small-angle neutron scattering (SANS) with contrast variation, the scattering signatures of the lysozyme and silica within the composite were separated. It was determined that the lysozyme molecules are spatially correlated in the material and form clusters with colloidal silica particles. The size of the clusters determined by SANS agrees well with the structural architecture observed by TEM. BET analysis revealed that the surface area of the composite is relatively low (4.73 m2/g). However, after removal of the protein by heating to 200 °C, the surface area is increased by ,20%. In addition to demonstrating a well organized sol-gel synthesis which generates a functional material with antimicrobial applications, the analysis and modeling approaches described herein can be used for characterizing a wide range of mesoporous and ultrastructural materials. [source] Protein Localization in Silica Nanospheres Derived via Biomimetic MineralizationADVANCED FUNCTIONAL MATERIALS, Issue 18 2010Mateus B. Cardoso Abstract Lysozyme-templated precipitation of silica synthesized by sol-gel chemistry produces a composite material with antimicrobial properties. This study investigates the structural properties of the composite material that allow for retention of the antimicrobial activity of lysozyme. Scanning (SEM) and transmission (TEM) electron microscopy reveal that the composite has a hierarchical structure composed of quasi-spherical structures (,450 nm diameter), which are in turn composed of closely packed spherical structures of ,8,10 nm in diameter. Using small-angle neutron scattering (SANS) with contrast variation, the scattering signatures of the lysozyme and silica within the composite were separated. It was determined that the lysozyme molecules are spatially correlated in the material and form clusters with colloidal silica particles. The size of the clusters determined by SANS agrees well with the structural architecture observed by TEM. BET analysis revealed that the surface area of the composite is relatively low (4.73 m2/g). However, after removal of the protein by heating to 200 °C, the surface area is increased by ,20%. In addition to demonstrating a well organized sol-gel synthesis which generates a functional material with antimicrobial applications, the analysis and modeling approaches described herein can be used for characterizing a wide range of mesoporous and ultrastructural materials. [source] Ultra Low- k Films Derived from Hyperbranched Polycarbosilanes (HBPCS),ADVANCED FUNCTIONAL MATERIALS, Issue 24 2008Jitendra S. Rathore Abstract Dense and porous hyperbranched carbosiloxane thin films (HBCSO) are obtained by sol,gel processing using methylene-bridged hyperbranched polycarbosilanes (HBPCSs) with the general compositional formula {(OMe)2Si(CH2)}. Introduction of porosity is achieved using a porogen templating approach, allowing the control of the films' dielectric constant from 2.9 to as low as 1.8. Over the entire dielectric range, the HBCSO films exhibit exceptional mechanical properties, 2,3 times superior to those obtained for non-alkylene bridged organosiloxanes such as methylsilsesquioxanes (MSSQs) of similar densities and k -values. [source] A Joint Theoretical and Experimental Insight into the Electronic Structure of Chromophores Derived from 6H,12H -5,11-Methanodibenzo[b,f][1,5]diazocineHELVETICA CHIMICA ACTA, Issue 11 2007Vincent Lemaur Abstract We report on the synthesis and electronic spectra of the chiral, donor-acceptor (push-pull) chromophores (±)- 4 and (±)- 5 with a 6H,12H -5,11-methanodibenzo[b,f][1,5]diazocine scaffold (Scheme,1 and Fig.,2). The electronic structures of these compounds were investigated at a quantum-chemical level (Figs.,2 and 3). The chemical reactivity of 6H,12H -5,11-methanodibenzo[b,f][1,5]diazocine ((±)- 11) towards aromatic electrophilic substitution (Scheme,2 and Table) provided additional information about its electronic structure and confirmed nonnegligible delocalization of the lone pair of the bridge-head N-atoms in this heterocyclic system. [source] Ferromagnetism in ZnO Nanowires Derived from Electro-deposition on AAO Template and Subsequent Oxidation,ADVANCED MATERIALS, Issue 6 2008J. B. Yi ZnO wires are prepared from the oxidation of Zn wires, which are electrodeposited into AAO template. The ZnO wires show ferromagnetism at room temperature. A detailed study indicates that, owing to incomplete oxidation, Zn clusters embedded in the ZnO matrix may attribute to the room-temperature ferromagnetism. [source] Alumina-Template Synthesis of Fluorescent RuO2 Nanotubes Derived from Ru3(CO)12 Clusters,ADVANCED MATERIALS, Issue 5 2006H. Tan RuO2 nanotubes with diameters of 15,25,nm and up to 3,,m in length have been prepared by the thermal decomposition of Ru3(CO)12 inside alumina templates. The RuO2 (110) planes grow along the long axis of the straight crystalline nanotubes. The growth of these fluorescent nanotubes appears to have proceeded via mononuclear ruthenium carbonyl intermediates (see Figure). [source] The Addition Reaction of Samarium Enolates and 2-Haloenolates Derived from Esters, and Amides to Imines.ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 17 20094-Diamino Esters or Amides, Totally Stereoselective Synthesis of Enantiopure Abstract The addition reaction of samarium enolates and 2-haloenolates derived from esters and amides to imines takes place in an efficient manner. A novel protocol to perform the addition reaction of samarium enolates derived from esters or amides to chiral 2-aminoimines, with total stereoselectivity and without racemization, is also reported. The use of samarium enolates in place of other classic metallic enolates (lithium, magnesium, etc.) could be a valuable alternative to obtain enantiopure 3,4-diamino esters or amides, when enolates of low basicity are necessary. [source] Densification of the PLZT Films Derived from Polymer-Modified Solution by Tailoring Annealing ConditionsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2007Z. H. Du The Pb0.91La0.09(Zr0.65,Ti0.35)0.9775O3 films were prepared from the solution containing polyvinylpyrrolidone, with Mw of 360 000. A fast heating rate of 40°C/min was used to heat our samples to temperatures in the range of 550°,750°C for different durations. Both a rapid heating rate and isothermal holding at a proper temperature are found to be essential for obtaining dense and crack-free PLZT films. The TG-DTA and Fourier-transform infrared results indicated that the fast heating rate could keep a certain amount of polyvinylpyrrolidone residues undecomposed to a higher temperature (<700°C), which was found to be beneficial for the densification of the films during subsequent isothermal hold. The possible mechanisms responsible for the enhanced densification have been discussed. In addition, the effects of annealing temperature on the electrical and optical properties were also investigated. [source] Sintering and Microstructure Modification of Mullite/Zirconia Composites Derived from Silica-Coated Alumina PowdersJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2001Viktor Yaroshenko This paper addresses the densification and microstructure development during firing of mullite/zirconia composites made from silica-coated-alumina (SCA) microcomposite powders. Densification occurs in two stages: in the presence of a silica,alumina mixture and after conversion to mullite. The first stage of densification occurs through transient viscous phase sintering (TVS). This is best promoted by rapid heating, which delays the crystallization of silica to higher temperatures. A further sintering stage is observed following mullitization. The introduction of seeds promotes solid-state sintering, most probably due to refinement of the mullite matrix. For seed concentrations up to about 1% the sintering kinetics depend on seed concentration. This suggests that nucleation still remains the rate-controlling mullitization step. Above this concentration the reaction becomes growth controlled. Introduction of seeds also promotes direct mullitization without transient zircon formation that was observed in a previous study of the same process without seeding. Seeding also promotes the development of elongated grains by way of a solid-state recrystallization process. [source] Protonation-Induced Formation of a Stable Singlet Biradicaloid Derived from a Modified Sapphyrin Analogue,ANGEWANDTE CHEMIE, Issue 34 2010Masatoshi Ishida Dr. Radikal durch Ansäuern: Das neuartige Sapphyrin-Analogon 1 mit eingebundenem 1,10-Phenanthrolin-System (siehe Schema; R=COOEt, Ar=p -Tolyl) und Alkylidengruppen in meso-Stellung wurde synthetisiert und durch Protonierung in [1,3,H]3+ mit Singulettdiradikal-Charakter überführt. [source] Carbon Spiral Helix: A Nanoarchitecture Derived from Monovacancy Defects in Graphene,ANGEWANDTE CHEMIE, Issue 18 2010Xingfa Gao Dr. Das planare, magnetische Isomer ist die stabilste Art von Fehlstelle im Zentrum einer Graphen-Flocke, während in Kantennähe das nichtplanare, nichtmagnetische Spiro-Isomer stabiler wird. Unter hohen Temperaturen wandern die Fehlstellen an die Peripherie der Flocke. Das Spiro-Isomer eignet sich als Strukturbaustein für die Synthese von Kohlenstoffhelices (siehe Bild). [source] Leukocyte cDNA Analysis of NSD1 Derived from Confirmed Sotos Syndrome PatientsANNALS OF HUMAN GENETICS, Issue 6 2007M. Duno Summary Background: Haploinsufficiency of the NSD1 gene leads to Sotos syndrome (Sos), which is characterised by excessive growth, especially during childhood, distinct craniofacial features and variable degree of mental impairment. A wide spectrum of NSD1 mutations have been described in Sos patients, ranging from more than 100 different single nucleotide changes, to partial gene deletions, and to microdeletions of various sizes comprising the entire NSD1 locus. Objective: To investigate the NSD1 cDNA sequence in genetically confirmed Sos patients harbouring truncating and missense mutations. Method: Total RNA was isolated from a 250 ,l standard EDTA blood sample from nine genetically verified Sos patients, and subsequent reverse-transcribed into cDNA followed by PCR and direct sequencing of specific NSD1 cDNA sequences. Results: All nine mutations, including missense, nonsense and whole exon deletions, previously identified in genomic DNA, could confidently be detected in cDNA. Several NSD1 transcript splice variants were detected. Conclusion: Despite the fact that Sos is caused by haploinsufficiency, NSD1 transcripts containing nonsense and frame shift mutations can be detected in leukocyte-derived cDNA. The possibility therefore exists that certain NSD1 mutations are expressed and contribute to the phenotypic variability of Sos. NSD1 cDNA analysis is likely to enhance mutation detection in Sos patients. [source] Nondipolar Content of T Wave Derived from a Myocardial Source Simulation with Increased Repolarization InhomogeneityANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2009Milos Kesek M.D., Ph.D. Background: Several conditions with repolarization disturbances are associated with increased level of nondipolar components of the T wave. The nondipolar content has been proposed as a measure of repolarization inhomogeneity. This computer simulation study examines the link between increased nondipolar components and increased repolarization inhomogeneity in an established model. Methods: The simulation was performed with Ecgsim software that uses the equivalent double-layer source model. In the model, the shape of transmembrane potential is derived from biological recordings. Increased repolarization inhomogeneity was simulated globally by increasing the variance in action potential duration and locally by introducing changes mimicking acute myocardial infarction. We synthesized surface ECG recordings with 12, 18, and 300 leads. The T-wave residue was calculated by singular value decomposition. The study examined the effects of the number of ECG leads, changes in definition of end of T wave and random noise added to the signal. Results: Normal myocardial source gave a low level of nondipolar content. Increased nondipolar content was observed in the two types of increased repolarization inhomogeneity. Noise gave a large increase in the nondipolar content. The sensitivity of the result to noise increased when a higher number of principal components were used in the computation. Conclusions: The nondipolar content of the T wave was associated with repolarization inhomogeneity in the computer model. The measure was very sensitive to noise, especially when principal components of high order were included in the computations. Increased number of ECG leads resulted in an increased signal-to-noise ratio. [source] Märipa: To Know Everything The Experience of Power as Knowledge Derived from the Integrative Mode of ConsciousnessANTHROPOLOGY OF CONSCIOUSNESS, Issue 2 2003Robin RoddArticle first published online: 8 JAN 200 Shamans of the Piaroa ethnic group (southern Venezuela) conceive of power in terms of knowledge derived from visionary experiences. Märipa is an epistemology concerning the translation of knowledge derived from the integrative mode of consciousness, induced primarily through the consumption of plant hallucinogens, to practical effect during waking life. I integrate mythological, neurobiological, experiential, and ethnographic data to demonstrate what märipa is, and how it functions. The theory and method of märipa underlie not only Piaroa shamanic activity, but all aspects of Piaroa life; mythology, causality, eschatology, and history. Piaroa shamanic practices involve conditioning the mind to achieve optimal perceptual capacities that facilitate accurate prediction and successful psycho-social prescription. Piaroa shamans describe their technologies of consciousness in terms of gods and spirits, but also in terms of studying and the acquisition of information. Because neurobiological processes underlie the development and experience of märipa, the language of neurobiology enables a partial translation of this indigenous epistemology. The concepts of feed forward neural processing and somatic markers are central to the processes of mental imagery cultivation that Piaroa shamans employ to divine solutions to adaptive problems. Piaroa 'techniques of ecstasy' involve the ability to apply mythological templates of human adaptation to schemas of human behaviour based on years of social analysis in association with heightened information processing capacities derivative of refined experimentation with the integrative mode of consciousness. Keyordsshamanism, neurophenomenology inugrativeconsciousness, hallucinogens [source] Synthesis of New Nonclassical Acridines, Quinolines, and Quinazolines Derived from Dimedone for Biological EvaluationARCHIV DER PHARMAZIE, Issue 9 2010Osama I. El- Sabbagh Abstract New nonclassical acridines, quinolines, and quinazolines were prepared starting from cyclic , -diketones, namely dimedone, through application of Hantzsch addition, Michael addition, and Mannich reactions, respectively. The antimicrobial activity revealed that decahydroacridin-1,8-dione 2e bearing a 3-nitrophenyl group and hexahydroquinoline 4e having a 2,4-dichlorophenyl moiety were the most active compounds against both Gram-positive and -negative bacteria based upon using the disc diffusion method. Cytotoxic activity studies for decahydroacridin-1,8-diones 2a,e against liver carcinoma cells (HepG2) using the MTT cell viability assay revealed that decahydroacridin-1,8-dione bearing a 4-methylphenyl moiety 2d showed a higher cytotoxic activity (IC50,=,4.42,µg/mL) than the other derivatives. [source] Antinociceptive Activity of a New Benzofuranone Derived from a ChalconeBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 4 2009Pâmela Padaratz The aim of this work was the synthesis of a new benzofuranone compound and evaluation of its antinociceptive potential in mice. The new benzofuranone 4 was synthesized from chalcone 3. The antinociceptive activity of 4 was determined by writhing, formalin, capsaicin, and glutamate and hot-plate tests. Compound 4 caused potent and dose-related inhibition against the writhing test with ID50 6.1 (5.1,7.6) ,mol/kg, i.p., being about 15 times more active than the reference drugs, acetyl salicylic acid and acetaminophen. It was also effective in a dose-dependent manner in significantly reducing the painful stimulus in both phases of formalin, in the capsaicin and in the glutamate test with ID50 values of 27.3 (24.5,30.6) and 18.9 (18.5,19.4) ,mol/kg (first and second phase), 12.6 (9.8,16.2) and 24.5 (20.4,29.6) ,mol/kg respectively. The results showed that the studied compound exhibits both central and peripheral antinociceptive activities and might be further used as a model to obtain new and more potent analgesic drugs. [source] Nutrient Dynamics of Soil Derived from Different Parent Material on Barro Colorado Island, Panama,BIOTROPICA, Issue 2 2000Joseph B. Yavitt ABSTRACT I compared the concentrations of N, P, and S in both litter and mineral soil (0,15 cm depth) from three old-growth, tropical moist forests on Barro Colorado Island (BCI), Panama. Each site was on a different substrate (i.e., parent material), but otherwise had similar climate, vegetation, and topography. There were no site differences in concentrations of N and S for either litter or soil. Concentrations of litter P and soil-extractable P were greater for the andesite (igneous rock) site than for two sites on different sedimentary rocks; however, concentrations of several other litter and soil P fractions did not differ among sites. Patterns in soil P fractions suggested advanced soil development to the point that parent material has little control of P dynamics. Litter samples from each site, leached in the laboratory, released similar amounts of N, P, and S to the soil, indicating no differences in rates of turnover in the litter and in fluxes from litter into the mineral soil among sites. I expected more site differences in soil nutrient dynamics given vastly different parent materials and soil types (i.e., Oxisol vs. Alfisol) and very shallow soil on BCI that brings the parent material close to the plant root zone. Erosion and soil mixing may explain the uniformity in soil nutrient dynamics across the sites. [source] Kinetics and Film Properties of Boron Nitride Derived from Trimethoxyborane/Ammonia by Chemical Vapor Deposition,CHEMICAL VAPOR DEPOSITION, Issue 6 2004H. Strakov Abstract The kinetics of the CVD of boron nitride from trimethoxyborane (TMOB) and ammonia (NH3) under atmospheric pressure was investigated by varying the following process parameters: temperature, residence time of the reactants, molar fraction of TMOB, and the NH3/TMOB ratio, ,. A kinetic power law equation was derived, that describes the experimental results with good accuracy. The reaction order with respect to TMOB is found to be 0.9 and ,,0.2 with respect to NH3. Between 800,°C and 950,°C, the deposition rate is controlled by the surface reaction kinetics with apparent activation energy of 115.1,kJ,mol,1. The deposited BN films were characterized by IR spectroscopy, Raman spectroscopy, and X-ray diffraction (XRD). The microstructure of the deposits depends on the nature of the substrates used. Turbostratic boron nitride (t-BN) was deposited on graphite, and hexagonal boron nitride (h-BN) on alumina substrates. X-ray photoelectron spectroscopy (XPS) analyses show nearly stoichiometric BN films for deposition temperatures in the range 850,950,°C for high amounts of ammonia (100,<,,,<,150) in the feed gas. [source] ChemInform Abstract: Solvent-Free Synthesis of 1,5-Disubstituted Tetrazoles Derived from Baylis,Hillman Acetates as Potential TNF-, Inhibitors.CHEMINFORM, Issue 8 2010P. Srihari Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Reaction of Amines with Nitrones Derived from Chromone-3-carbaldehyde.CHEMINFORM, Issue 7 2010Sourav Maiti Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] | |||||||||||||||||||||||||||||||||||||