bluuebunny/crossref_metadata_2025_split huggingface dataset:
Beschleunigung der Pauson‐Khand‐Reaktion durch primäre Amine
Authors: Sugihara Takumichi , Yamada Mamiko , Ban Hitoshi , Yamaguchi Masahiko , Kaneko Chikara 
Published: July 2007

Ökonomisch und praktisch sind neu entwickelte Reaktionsbedingungen für die Pauson‐Khand‐Reaktion, die den Befund nutzen, daß primäre Amine diese Reaktion beschleunigen. Im einen Fall werden mehr als drei Äquivalente Cyclohexylamin in 1,2‐Dichlorethan bei 83 °C verwendet und im anderen ein Gemisch aus 1,4‐Dioxan und 2 M wäßrigem NH3 (1/3, v/v) bei 100°C, Unter diesen Bedingungen ist z.B. die unten gezeigte Cyclisierung nach 5 bzw. 15 min vollständig abgelaufen, und das Produkt kann in 99 bzw. 93% Ausbeute isoliert werden.magnified image
β‐Donorbindungen in Molekülen mit SiON‐Einheiten
Authors: Mitzel Norbert W. , Losehand Udo 
Published: July 2007

Deutlich komprimiert sind die SiON‐Winkel von H3SiONMe2 (Struktur im Kristall siehe rechts) und H2Si(ONMe2)2 gegenüber den SiOC‐Winkeln isoelektronischer Verbindungen mit SiOC‐Einheiten. Der Grund dafür ist eine schwache Donor‐Acceptor‐Bindung zwischen den Si‐ und N‐Atomen. Die resultierende schwache Hyperkoordination am Si‐Atom erklärt das besondere chemische Verhalten dieser Verbindungen.magnified image
Synthese und Struktur des ersten Samarium(II)‐Komplexes mit σ‐gebundenen Alkylliganden und dessen Reaktion mit Benzophenon
Authors: Clegg William , Izod Keith , O'Shaughnessy Paul , Eaborn Colin , Smith J. David 
Published: July 2007

Erstmals strukturell charakterisiert wurde jetzt ein Samarium(II)‐Komplex mit σ‐gebundenen Alkylliganden. Diese Verbindung, in der zwei C(SiMe3)2(SiMe2OMe)‐Liganden über die carbanionischen Kohlenstoffzentren und die Sauerstoffzentren der Methoxygruppen an das Samariumzentrum gebunden sind (siehe Struktur rechts), reagiert mit Benzophenon zum entsprechenden Ketylradikalanion‐Samarium(III)‐Komplex.magnified image
Strukturelle Reorganisation von Stilbenanalogen Verbindungen mit ausgedehnten π‐Elektronensystemen durch Oxidation und Reduktion
Authors: Knorr Andreas , Daub Jörg 
Published: July 2007

Von der benzoiden Struktur 1 zu der chinoiden Struktur 2 gelangt man durch den Transfer von zwei Elektronen. Diese Schlußfolgerung wird durch cyclovoltammetrische und spektroelektrochemische Daten gestützt, die mit den Befunden quantenmechanischer Rechnungen auf semiempirischem Niveau in Einklang sind.magnified image
Chromkomplex‐katalysierte [2+1]‐Cycloaddition von Diazoalkanen an Enolether — erste direkte spektroskopische Beobachtung eines intermediären Carbenkomplexes
Authors: Pfeiffer Jürgen , Dötz Karl Heinz 
Published: July 2007

Eine neue katalytische Synthese von Cyclopropanen aus Alkenen und Diazoverbindungen ermöglicht Pentacarbonyl (n2‐cis‐cycloocten)chrom(0), aus dem intermediär “Cr(CO)5” entsteht. Die Reaktionen (1) zeichnen sich durch eine ausgeprägte Chemoselektivität der beteiligten Carbenkomplex‐Intermediate 1 aus, die die eindeutige Unterscheidung verschiedenartig substituierter Alkene ermöglicht.magnified image
Synthesis and characterization of dual‐functionalized laponite clay for acrylic nanocomposites
Authors: Wang Junzuo , Wheeler Paul A. , Jarrett William L. , Mathias Lon J. 
Published: July 2007

AbstractDual‐functional laponites were synthesized by a condensation reaction with silane coupling agents followed by cation exchange reaction with quaternary ammonium salts. FTIR and solid state 13C CP/MAS NMR confirmed their structures. Quantitative solid state 29Si DP/MAS NMR spectra indicated that clay silanol groups reacted with silane coupling agents by a decrease in the silanol peak and appearance of a new SiOSi peak. Dual‐functionalized laponites showed improved dispersion in organic solvents and vinyl monomers. One dual‐functional laponite modified with both photosensitizer and coinitiator photo‐initiated polymerization of an acrylate (2‐phenoxyethyl acrylate, PEA) and a methacrylate (MHMA, methyl α‐hydroxymethylacrylate). TEM showed laponite clay sheets were exfoliated in poly(PEA); while a combination of exfoliated, intercalated and tactoid morphologies was found in poly(methyl α‐hydroxymethylacrylate). The other dual‐functionalized laponite clay with edge‐bound methacrylate units copolymerized with methyl methacrylate and led to a high grafting amount and graft efficiency. PMMA nanocomposites showed higher storage modulus both below and above the glass transition temperature compared to the PMMA control. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
He who pays the piper calls the tune?
Authors: Oliver Caroline 
Published: July 2007

AbstractFunding may be vital to the operations of any organization, but that does not mean that the funders should determine an organization's ends. As Caroline Oliver, general editor of the Policy Governance Fieldbook and current chair of the International Policy Governance Association, points out here, the board is beholden to the ownership before any other stakeholders, funders included. That is why the only group that legitimately “calls the tune” is the ownership. Caroline Oliver can be contacted at (905) 337‐9412.
The cult of efficiency
Authors: Oliver Caroline 
Published: July 2007

AbstractOn 1964, a professor named Raymond Callahan published a book titled Education and the Cult of Efficiency, and since then the concept has worked its way into general organizational parlance. In Policy Governance terms, the “cult of efficiency” describes a dangerous preoccupation with means without first identifying ends. How can we know if we're efficient if we don't first understand what it is we're trying to accomplish? The cult of efficiency is the subject of a recent lecture by a conflict management professor named Janice Gross Stein, later published in book form. In this article, Caroline Oliver considers the ways in which Stein's ideas about the cult of efficiency coincide with, and differ from, the Policy Governance concepts of ends and means.
Isolation and Chemical Modification of Clerodane Diterpenoids fromSalviaSpecies as Potential Agonists at theκ‐Opioid Receptor
Authors: Li Yiqiang , Husbands Stephen M. , Mahon Mary F. , Traynor John R. , Rowan Michael G. 
Published: July 2007

AbstractThe clerodane diterpenoid salvinorin A (1), the main active component of the psychotropic herbSalvia divinorum, has been reported to be a potent agonist at theκ‐opioid receptor. Computer modeling suggested that splendidin (2) fromS. splendens, as well as related compounds, might possess similar activities. In the present study, this hypothesis was tested by determination of the binding properties of a series of structural congeners, compounds2–8, at theμ‐,δ‐, andκ‐opioid receptors. However, none of these compounds showed significant binding to any of the opioid‐receptor subtypes, thus disproving the above hypothesis.The novel compounds7and8were obtained semi‐synthetically by selective modification of salvifarin (5), isolated fromSalvia farinacea, upon epoxide‐ring opening with AcOH in the presence of indium(III) triflate. Also, the X‐ray crystal structure of salvifaricin (6;Fig.), obtained fromS. farinacea, was determined for the first time and used, in combination with in‐depth NMR experiments, to elucidate the absolute configurations of the new products. Our experiments demonstrate that the relatively well‐accessible diterpenoid6could be used as starting material for future studies into the structure–activity relationship at theκ‐opioid receptor.
A New Dihydroagarofuranoid Sesquiterpene from Microtropis fokienensis with Antituberculosis Activity
Authors: Chou Tsung‐Hsien , Chen Ih‐Sheng , Sung Ping‐Jyun , Peng Chien‐Fang , Shieh Po‐Chuen , Chen Jih‐Jung 
Published: July 2007

AbstractA new dihydroagarofuran‐based sesquiterpene, 8‐acetoxymutangin (1), was isolated from the stems of Microtropis fokienensis, together with eight known compounds, including mutangin (2). Their structures were determined through in‐depth spectroscopic and mass‐spectrometric analyses. Among the isolated compounds, 1 exhibited potent in vitro antituberculosis activity, with an MIC value of 10.0 μg/ml against Mycobacterium tuberculosis 90‐221387, which is considerably better than that of mutangin (2). The activity of 1 lies in the same range as that of the clinic drug ethambutol (MIC 6.25 μg/ml), despite completely different chemical structures, which indicates different modes of action.
Stereochemistry of Enacyloxins. Part 4
Authors: Furukawa Hiroyuki , Kiyota Hiromasa , Yamada Teiko , Yaosaka Manabu , Takeuchi Ryo , Watanabe Toshihiko , Kuwahara Shigefumi 
Published: July 2007

AbstractThe absolute configurations of the enacyloxins, a series of polyhydroxylated polyene antibiotics from Frateuria species, were determined. The so far elusive (13′R,14′R,15′S)‐configuration was assigned to enacycloxin IVa (1) by means of ‘J‐resolved HMBC‐1’ and NOESY NMR methods.
Structural and Magnetic Modulation of a Purely Organic Open Framework by Selective Guest Inclusion
Authors: Maspoch Daniel , Domingo Neus , Roques Nans , Wurst Klaus , Tejada Javier , Rovira Concepció , Ruiz‐Molina Daniel , Veciana Jaume 
Published: July 2007

AbstractSolvent inclusion/evacuation caused variations in the structural and magnetic characteristics of the purely organic porous magnet based on the tricarboxylic‐substituted PTMTC radical. Whereas no inclusion is observed for nonpolar solvents, the exposure of crystals of the α‐phase of PTMTC to vapors of polar organic solvents with hydrogen acceptor and/or donor functionalities, such as, ethanol, benzoic alcohol, n‐decanol, THF, and DMSO results in the inclusion of these solvents in the highly polar tubular channels of the α‐phase. The resulting inclusion compounds of formula PTMTC⋅ x(guest) show several structural rearrangements, as confirmed by IR and XRPD (X‐ray powder diffraction) measurements. The crystal transformations have been studied for a specific case: the PTMTC⋅EtOH adduct. The crystal structure reveals that included guest solvent molecules participate in the formation of new hydrogen bonds with the carboxylic groups of PTMTC radicals, inducing the disruption of several direct hydrogen bonds among these radicals. As expected, the interruption of direct hydrogen bonds between PTMTC radicals induces large transformations in the magnetic properties. From the ferromagnetic behavior of the α‐phase, predominant antiferromagnetic interactions are observed for the inclusion adducts. Interestingly, both structural and magnetic changes are reversible after removal of guest solvent molecules.
Water as a Building Block in Solid‐State Acetonitrile–Pyrogallol[4]arene Assemblies: Structural Investigations
Authors: Dalgarno Scott J. , Antesberger Jochen , McKinlay Robert M. , Atwood Jerry L. 
Published: July 2007

AbstractUnder various conditions, water molecules dramatically affect a number of solid‐state C‐alkylpyrogallol[4]arene assemblies. In the absence of water, hydrogen‐bonded hexameric capsules are formed for the C‐butyl, pentyl, hexyl, and heptyl pyrogallol[4]arenes. Introduction of water to acetonitrile solutions containing C‐propyl–C‐octylpyrogallol[4]arenes resulted in the formation of markedly different bilayer structures and the structural identification of two new dimer‐type motifs.
Competitive intelligence and tacit knowledge development in strategic alliances
Authors: Levitas Edward , Hitt Michael A , Dacin M. Tina 
Published: July 2007

AbstractCompetitive intelligence can play a vital role in helping management select strategic alliances that will result in a transfer of the partner's tacit knowledge—the implicitly understood norms and rules that guide operating procedures within a firm. Learning a partner's tacit knowledge can help a firm learn more about its own strengths and weaknesses. To maximize the value of knowledge gained from alliances, competitive intelligence professionals should monitor a potential partner's activities in order to: ascertain whether collaboration will provide a firm with learning opportunities; convince management of the value of learning from that particular partner; and prepare employees to enter the collaboration with an intent to learn, thereby maximizing “absorptive capacity.” A well‐developed CI strategy also can alert managers to potential problems that can result, for instance, from a lack of complementary resources or the absence of shared, strategic goals, and can help avoid alliances with partners whose primary intent is to acquire your firm's technical knowledge to use as a competitive weapon. © 1997 John Wiley & Sons, Inc.
The japanese investigative industry: Toward the year 2000
Authors: Toshiro HǑSei 
Published: July 2007

AbstractUnderstanding the Japanese approach to professional private investigations can provide insight into Japanese competitive intelligence, especially since the collection of business information—often related to proposed mergers and acquisitions—is a task that many investigative firms provide. The intelligence gathered also commonly focuses on intellectual property‐related matters, leaks of corporate information, industrial espionage incidents, and technical surveillance countermeasures. There is currently no Japanese law governing the private investigative industry and no legal obligation to register in order to open an agency. However, firms are expected to carry out investigations in a legal and ethical manner, and industry leaders are promoting greater professionalization. At the forefront of this effort is the Japan Investigative Services Association, which has some 2,000 member firms nationwide. About 90% of these are small and medium enterprises capitalized at less than US$100,000. Almost all have fewer than 50 employees. The Tokyo Intelligence and Research College, established in 1992, is also aiding professionalization by producing qualified investigative specialists. © 1997 John Wiley & Sons, Inc.
Synthesis of Novel Phosphorylated Daidzein Derivatives and ESI Investigation on Their Non‐Covalent Complexes with Lysozyme
Authors: Chen Xiao‐Lan , Shi Xiao‐Na , Qu Ling‐Bo , Yuan Jin‐Wei , Lu Jian‐Sha , Lu Yu‐Fen 
Published: July 2007

AbstractDaidzein (7,4′‐dihydroxyisoflavone) was phosphorylated by a modified Atherton‐Todd reaction. The structures of the five target product, were determined by X‐ray, IR, NMR and ESI‐MS. Electrospray ionization results show that in the gas phase all the phosphorylated daidzein derivatives could form non‐covalent complexes with the protein lysozyme, while non‐covalent complexes were not detected in the mixed solution of daidzein with lysozyme. Relative affinity of every non‐covalent complex was obtained according to its different decomposition orifice voltage.
Study of Dehydrocoupling Reactions of Diorganotin Dihydrides R1R2SnH2 with Biuret
Authors: Deep Gagan , Narula A. K. 
Published: July 2007

AbstractThe reaction of unsymmetrical phenylmethyltin dihydride (PhMeSnH2), phenylethyltin dihydride (PhEtSnH2), phenylbutyltin dihydride (PhBuSnH2) and butylmethyltin dihydride (BuMeSnH2) with biuret (H2L) proceeds via SnH/NH dehydrocoupling to afford the corresponding tetra‐coordinate cyclic products. The reactions in the molar ratios of 1:1, 2:1 and 1:2 have been studied. The yellow derivatives so isolated were soluble in polar solvents and insoluble in nonpolar solvents. It was found that 1:1 reaction went to completion while 2:1 and 1:2 did not go to completion. The derivatives had been characterized by elemental analysis and spectroscopic techniques viz. IR, 1H NMR, 13C NMR, 119Sn NMR. DSC and TGA of the reaction products have also been studied. All the derivatives were thermally stable upto (190±10) °C and degradation occurred after that.
Simultaneous Determination of Epinephrine, Noradrenaline and Dopamine in Human Serum Samples by High Performance Liquid Chromatography with Chemiluminescence Detection
Authors: Chen Fu‐Nan , Zhang Ying‐Xue , Zhang Zhu‐Jun 
Published: July 2007

AbstractA simple, rapid and accurate high performance liquid chromatographic (HPLC) technique coupled with chemiluminescence (CL) detection was developed for the simultaneous determination of epinephrine (E), noradrenaline (NA) and dopamine (DA). It was based on the analyte enhancement effect on the CL reaction between luminol and potassium ferricyanide. The effects of various parameters, such as potassium ferricyanide concentration, luminol concentration, pH value and component of the mobile phase on chromatographic behaviors of the analytes (E, NA and DA) were investigated. The separation was carried out on C18 column using the mobile phase of 0.01 mol/L potassium hydrogen phthalate solution and methanol (92:8, V/V). Under the optimum conditions, E, NA and DA showed good linear relationships in the range of 1×10−8–5×10−6, 5.0×10−9–1.0×10−6 and 5.0×10−9–1.0×10−6 g/mL respectively. The detection limits for E, NA and DA were 4.0×10−9, 1.0×10−9 and 8.0×10−10 g/mL. The proposed method has been applied successfully to the analysis of E, NA and DA in human serum samples.
Determination of Potassium Ferrocyanide in Foods by Resonance Rayleigh Scattering Method with Double‐Charged Triaminotriphenylmethane Dyes
Authors: Li Yong‐Li , Liu Zhong‐Fang , Xie Li‐Sha , Kong Ling , Liu Shao‐Pu 
Published: July 2007

AbstractIn pH 1.0 acidic medium, double‐charged triaminotriphenylmethane dyes such as methyl green (MeG) and iodine green (IG) react with potassium ferrocyanide to form 2:1 ion‐association complexes by virtue of electrostatic forces and hydrophobic interaction. It results in the change of absorption and the great enhancement of resonance Rayleigh scattering (RRS) and the appearance of new RRS spectra. Two systems have similar spectral characteristics and their maximum RRS wavelengths are all located at 276 nm and smaller peaks are located at 332 and 457 nm, respectively. The intensity of RRS is directly proportional to the concentration of [Fe(CN)6]4− in the range of 0.03–5.7 µg·mL−1 (MeG system) or 0.04–5.9 µg·mL−1 (IG system). The RRS method has high sensitivity and the detection limit (3σ) for potassium ferrocyanide is 9.3 ng·mL−1 (MeG system) or 11.2 ng·mL−1 (IG system). The optimum conditions, influencing factors and effects of foreign substances are investigated. The method also has a good selectivity. A sensitive, rapid and simple RRS method for the determination of potassium ferrocyanide in salinized food and table salt has been developed.
An Efficient Synthetic Method to Nonnatural α‐ and β‐Tryptophan Analogues via Friedel‐Crafts Alkylation of Indoles with Nitroacrylates
Authors: Sui Yong , Liu Li , Wang Dong , Chen Yong‐Jun 
Published: July 2007

AbstractThe Friedel‐Crafts alkylation of indoles with nitroacrylates could provide α‐ and β‐tryptophan nitro‐precursors, respectively, in moderate to good yields under Lewis acid catalysis. The diastereoselectivities of the reaction were enhanced by using 2‐substituted indoles. The alkylation products could be easily transformed to nonnatural tryptophan derivatives.
Acid Catalyzed Condensation of Phenylethanal Enol or Thiol Enol Ether to 2‐Phenylnaphthalene
Authors: Chang Yu‐An 
Published: July 2007

AbstractTreatment of enol ether or thiol enol ether of phenylethanals with sulfuric or polyphosphoric acid in toluene or xylene gave 2‐phenylnaphthalene in good yield. More importantly, a one‐pot reaction has been developed.
Synthesis and Characterization of Fluoro‐ and Chloro‐bimetallic Alkoxides as Precursors for Luminescent Metal Oxide Materials via Sol‐Gel Technique
Authors: Athar Taimur , Seok Sang Il , Kwon Jeong Oh 
Published: July 2007

AbstractHeterobimetallic alkoxides are broadly recognized as versatile precursors for luminescence materials, and efforts are being made to develop novel routes by applying the concept of geometrical molecular design, for their synthesis and to design a single source precursor suited to photoluminescent materials. Novel and new series of bimetallic alkoxides has been prepared by metathesis route. They exhibit a lower sensitivity towards hydrolysis and so they are easier to handle as compared to other alkoxides. All the compounds were characterized by elemental analysis, FT‐IR and multinuclear NMR spectroscopies. FT‐IR revealed that the molecular structure of these metal alkoxides was retained to a large extent in 4:1 halogenated alcohol‐benzene solution. The heteronuclear NMR spectroscopy provided useful information about chemical shifts for better understanding the likely structure based on interactions with their coordinate metals. The mass spectra show similar types of fragmentation pattern. SEM‐EDS analyses showed consistency with the formulation. XRD patterns show an enhanced homogeneity at high temperature. TGA measurements show that thermal decomposition occured in steps that depended entirely on the chemical compositions and the synthesis routes. SEM observation reveals that the morphology and particle size strongly depend on synthesis routes for their precursors.
Expression of estrogen receptor‐α and ‐β mRNA in the brain of Japanese quail embryos
Authors: Axelsson Jeanette , Mattsson Anna , Brunström Björn , Halldin Krister 
Published: July 2007

AbstractThe present study was conducted to investigate the mRNA expression of the two estrogen receptor (ER) subtypes ERα and ERβ in the brain of Japanese quail embryos. We found expression of both ERα and ERβ mRNA in homogenate of whole head from 6‐day‐old embryos, and in brain homogenate from 9‐ and 12‐day‐old embryos using real‐time PCR. In 9‐ and 12‐day‐old embryos the ERα expression was higher in females than in males. We used in situ hybridization to examine the localization of the ERs in sections from male and female brains on day 9 and day 17 of incubation. On day 9, ERβ mRNA was detected in the developing medial preoptic nucleus (POM), in the medial part of the bed nucleus of the striae terminalis (BSTm), and in the tuberal region of the hypothalamus. ERα signal could not be detected in the POM, the BSTm or the tuberal region in 9‐day‐old embryos. In 17‐day‐old embryos, ERβ was highly expressed in the preoptic area, the nucleus Taeniae of the Amygdala (TnA) and the BSTm. Expression of ERα mRNA was detected in parts of the preoptic area and in the telencephalic TnA. No ERα expression was found in the BSTm, an area known to be sexually dimorphic in adults. The high embryonic expression of ERβ in brain areas linked to sexual behavior indicates that ERβ plays a role in sexual differentiation of the Japanese quail brain. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007.
Learning large‐scale spatial relationships in a maze and effects of MK‐801 on retrieval in the rhesus monkey
Authors: Wang Jian Hong , Zhang Bo , Meng Zhi Qiang , Sun Ning Lei , Ma Man Xiu , Zhang Hua Xian , Tang Xiangdong , Sanford Larry D. , Wilson Fraser A.W. , Hu Xin Tian , Carlson Synnöve , Ma Yuan‐Ye 
Published: July 2007

AbstractMonkeys have strong abilities to remember the visual properties of potential food sources for survival in the nature. The present study demonstrated the first observations of rhesus monkeys learning to solve complex spatial mazes in which routes were guided by visual cues. Three monkeys were trained in a maze (6 m × 6 m) included of four different mazes. We recorded the cue and cup errors, latencies, and pathway for each trial. The data showed that monkeys learned the target place after three days in the first maze and spent a shorter time in learning the following mazes. The maze was an efficient method to measure the ability and proceeding of spatial memory in monkeys. Moreover, working memory can also be tested by using the maze. MK‐801 at 0.02 mg/kg but not at 0.005 mg/kg impaired monkeys' retrieval of spatial memory after they learned all four mazes. The present maze may provide an efficient method to help bridging the gap in cognition between nonhuman primates and humans, and in particular to gain insight into human cognitive function and dysfunction. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007.