WorldWideScience

Sample records for benzimidazole probe molecules

  1. Mass analyzed threshold ionization spectroscopy of aza-aromatic bicyclic molecules: Benzimidazole and benzotriazole

    International Nuclear Information System (INIS)

    Lin, J.L.; Li, Y.C.; Tzeng, W.B.

    2007-01-01

    We report the vibrationally resolved cation spectra of benzimidazole and benzotriazole, which give the respective adiabatic ionization energies (IEs) to be 67552 ± 5 cm -1 and 70474 ± 5 cm -1 . Comparing these data with that of indole, one finds that the IE of these aza-aromatic bicyclic molecules increases with the number of the N atoms. Most of the active modes of the benzimidazole cation are related to the in-plane ring vibrations. In contrast, the observed spectral bands of the benzotriazole cation correspond to the out-of-plane N2-H and skeleton N1N2N3 bending vibrations. These experimental findings may be attributed to the nature and the N atoms in the five-membered ring

  2. Differential sensing of fluoride and cyanide ions by using Dicyano substituted benzimidazole probe

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Akul Sen; Garg, Aparna; Paul, Kamaldeep; Luxami, Vijay, E-mail: vluxami@thapar.edu

    2016-05-15

    Excited State Intramolecular Proton Transfer based benzimidazole derivative having push–pull effect has been synthesized and investigated their photophysical behavior towards various anions. The probe 2 has been used for selective estimation of F{sup −} and CN{sup −} anions and signaled the binding event through formation of new absorption band at 465 nm. The probe 2 opens different emission channels at 425 nm in the presence of CN{sup −} ions and two new emission bands at 435 nm and 365 nm in case of F{sup −} ions. The probe 2 behaved as chemodosimeter for CN{sup −} ions which have been proved by {sup 1}H NMR and whereas fluoride caused hydrogen bonding interactions with probe 2 and restricted the ESIPT emission at 505 nm from OH to nitrogen of benzimidazole moiety to release its enol emission. The differential behavior of F{sup −} ions and CN{sup −} have been confirmed through DFT calculations. - Graphical abstract: The probe 2 binds chemodosimetrically with cyanide ions and act as chemosensor for fluoride ion.

  3. Differential sensing of fluoride and cyanide ions by using Dicyano substituted benzimidazole probe

    International Nuclear Information System (INIS)

    Gupta, Akul Sen; Garg, Aparna; Paul, Kamaldeep; Luxami, Vijay

    2016-01-01

    Excited State Intramolecular Proton Transfer based benzimidazole derivative having push–pull effect has been synthesized and investigated their photophysical behavior towards various anions. The probe 2 has been used for selective estimation of F − and CN − anions and signaled the binding event through formation of new absorption band at 465 nm. The probe 2 opens different emission channels at 425 nm in the presence of CN − ions and two new emission bands at 435 nm and 365 nm in case of F − ions. The probe 2 behaved as chemodosimeter for CN − ions which have been proved by 1 H NMR and whereas fluoride caused hydrogen bonding interactions with probe 2 and restricted the ESIPT emission at 505 nm from OH to nitrogen of benzimidazole moiety to release its enol emission. The differential behavior of F − ions and CN − have been confirmed through DFT calculations. - Graphical abstract: The probe 2 binds chemodosimetrically with cyanide ions and act as chemosensor for fluoride ion.

  4. A turn-on supramolecular fluorescent probe for sensing benzimidazole fungicides and its application in living cell imaging

    Science.gov (United States)

    Tang, Qing; Zhang, Jing; Sun, Tao; Wang, Cheng-Hui; Huang, Ying; Zhou, Qingdi; Wei, Gang

    2018-02-01

    A cucurbit[8]uril-based turn-on supramolecular fluorescent probe between cucurbit[8]uril (Q[8]) and pyronine Y (PyY) (designated 2PyY@Q[8]) in acidic aqueous solution showed a remarkable fluorescence 'turn-on' response to benzimidazole fungicides such as thiabendazole, fuberidazole and carbendazim. The 2PyY@Q[8] fluorescent probe can be used to detect benzimidazole fungicides with high sensitivity and selectivity with a detection limit of 10- 8 mol/L. A good linear relationship of emission intensity at 580 nm for benzimidazole fungicides at concentrations of 0.4-5.0 μmol/L was observed. The proposed sensing mechanism was investigated using 1H NMR spectroscopy combined with density functional theory calculations at the B3LYP/6-31G(d) level. The cell imaging study showed that the 2PyY@Q[8] complex could be used to image benzimidazole fungicide in prostate cancer (PC3) cells, which may help to elucidate relevant biological processes at the molecular level.

  5. Small molecule probes for cellular death machines.

    Science.gov (United States)

    Li, Ying; Qian, Lihui; Yuan, Junying

    2017-08-01

    The past decade has witnessed a significant expansion of our understanding about the regulated cell death mechanisms beyond apoptosis. The application of chemical biological approaches had played a major role in driving these exciting discoveries. The discovery and use of small molecule probes in cell death research has not only revealed significant insights into the regulatory mechanism of cell death but also provided new drug targets and lead drug candidates for developing therapeutics of human diseases with huge unmet need. Here, we provide an overview of small molecule modulators for necroptosis and ferroptosis, two non-apoptotic cell death mechanisms, and discuss the molecular pathways and relevant pathophysiological mechanisms revealed by the judicial applications of such small molecule probes. We suggest that the development and applications of small molecule probes for non-apoptotic cell death mechanisms provide an outstanding example showcasing the power of chemical biology in exploring novel biological mechanisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Effect of the physicochemical parameters of benzimidazole molecules on their retention by a nonpolar sorbent from an aqueous acetonitrile solution

    Science.gov (United States)

    Shafigulin, R. V.; Safonova, I. A.; Bulanova, A. V.

    2015-09-01

    The effect of the structure of benzimidazoles on their chromatographic retention on octadecyl silica gel from an aqueous acetonitrile eluent was studied. One- and many-parameter correlation equations were obtained by linear regression analysis, and their prognostic potential in determining the retention factors of benzimidazoles under study was analyzed.

  7. Small molecule probes for plant cell wall polysaccharide imaging

    Directory of Open Access Journals (Sweden)

    Ian eWallace

    2012-05-01

    Full Text Available Plant cell walls are composed of interlinked polymer networks consisting of cellulose, hemicelluloses, pectins, proteins, and lignin. The ordered deposition of these components is a dynamic process that critically affects the development and differentiation of plant cells. However, our understanding of cell wall synthesis and remodeling, as well as the diverse cell wall architectures that result from these processes, has been limited by a lack of suitable chemical probes that are compatible with live-cell imaging. In this review, we summarize the currently available molecular toolbox of probes for cell wall polysaccharide imaging in plants, with particular emphasis on recent advances in small molecule-based fluorescent probes. We also discuss the potential for further development of small molecule probes for the analysis of cell wall architecture and dynamics.

  8. Probing Intranuclear Environments at the Single-Molecule Level

    Science.gov (United States)

    Grünwald, David; Martin, Robert M.; Buschmann, Volker; Bazett-Jones, David P.; Leonhardt, Heinrich; Kubitscheck, Ulrich; Cardoso, M. Cristina

    2008-01-01

    Genome activity and nuclear metabolism clearly depend on accessibility, but it is not known whether and to what extent nuclear structures limit the mobility and access of individual molecules. We used fluorescently labeled streptavidin with a nuclear localization signal as an average-sized, inert protein to probe the nuclear environment. The protein was injected into the cytoplasm of mouse cells, and single molecules were tracked in the nucleus with high-speed fluorescence microscopy. We analyzed and compared the mobility of single streptavidin molecules in structurally and functionally distinct nuclear compartments of living cells. Our results indicated that all nuclear subcompartments were easily and similarly accessible for such an average-sized protein, and even condensed heterochromatin neither excluded single molecules nor impeded their passage. The only significant difference was a higher frequency of transient trappings in heterochromatin, which lasted only tens of milliseconds. The streptavidin molecules, however, did not accumulate in heterochromatin, suggesting comparatively less free volume. Interestingly, the nucleolus seemed to exclude streptavidin, as it did many other nuclear proteins, when visualized by conventional fluorescence microscopy. The tracking of single molecules, nonetheless, showed no evidence for repulsion at the border but relatively unimpeded passage through the nucleolus. These results clearly show that single-molecule tracking can provide novel insights into mobility of proteins in the nucleus that cannot be obtained by conventional fluorescence microscopy. Our results suggest that nuclear processes may not be regulated at the level of physical accessibility but rather by local concentration of reactants and availability of binding sites. PMID:18065482

  9. Heterobifunctional crosslinkers for tethering single ligand molecules to scanning probes

    International Nuclear Information System (INIS)

    Riener, Christian K.; Kienberger, Ferry; Hahn, Christoph D.; Buchinger, Gerhard M.; Egwim, Innocent O.C.; Haselgruebler, Thomas; Ebner, Andreas; Romanin, Christoph; Klampfl, Christian; Lackner, Bernd; Prinz, Heino; Blaas, Dieter; Hinterdorfer, Peter; Gruber, Hermann J.

    2003-01-01

    Single molecule recognition force microscopy (SMRFM) is a versatile atomic force microscopy (AFM) method to probe specific interactions of cognitive molecules on the single molecule level. It allows insights to be gained into interaction potentials and kinetic barriers and is capable of mapping interaction sites with nm positional accuracy. These applications require a ligand to be attached to the AFM tip, preferably by a distensible poly(ethylene glycol) (PEG) chain between the measuring tip and the ligand molecule. The PEG chain greatly facilitates specific binding of the ligand to immobile receptor sites on the sample surface. The present study contributes to tip-PEG-ligand tethering in three ways: (i) a convenient synthetic route was found to prepare NH 2 -PEG-COOH which is the key intermediate for long heterobifunctional crosslinkers; (ii) a variety of heterobifunctional PEG derivatives for tip-PEG-ligand linking were prepared from NH 2 -PEG-COOH; (iii) in particular, a new PEG crosslinker with one thiol-reactive end and one terminal nitrilotriacetic acid (NTA) group was synthesized and successfully used to tether His 6 -tagged protein molecules to AFM tips via noncovalent NTA-Ni 2+ -His 6 bridges. The new crosslinker was applied to link a recombinant His 6 -tagged fragment of the very-low density lipoprotein receptor to the AFM tip whereupon specific docking to the capsid of human rhinovirus particles was observed by force microscopy. In a parallel study, the specific interaction of the small GTPase Ran with the nuclear import receptor importin β1 was studied in detail by SMRFM, using the new crosslinker to link His 6 -tagged Ran to the measuring tip [Nat. Struct. Biol. (2003), 10, 553-557

  10. Probing Zeolite Crystal Architecture and Structural Imperfections using Differently Sized Fluorescent Organic Probe Molecules.

    Science.gov (United States)

    Hendriks, Frank C; Schmidt, Joel E; Rombouts, Jeroen A; Lammertsma, Koop; Bruijnincx, Pieter C A; Weckhuysen, Bert M

    2017-05-05

    A micro-spectroscopic method has been developed to probe the accessibility of zeolite crystals using a series of fluorescent 4-(4-diethylaminostyryl)-1-methylpyridinium iodide (DAMPI) probes of increasing molecular size. Staining large zeolite crystals with MFI (ZSM-5) topology and subsequent mapping of the resulting fluorescence using confocal fluorescence microscopy reveal differences in structural integrity: the 90° intergrowth sections of MFI crystals are prone to develop structural imperfections, which act as entrance routes for the probes into the zeolite crystal. Polarization-dependent measurements provide evidence for the probe molecule's alignment within the MFI zeolite pore system. The developed method was extended to BEA (Beta) crystals, showing that the previously observed hourglass pattern is a general feature of BEA crystals with this morphology. Furthermore, the probes can accurately identify at which crystal faces of BEA straight or sinusoidal pores open to the surface. The results show this method can spatially resolve the architecture-dependent internal pore structure of microporous materials, which is difficult to assess using other characterization techniques such as X-ray diffraction. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  11. Excitonic Coupling in Linear and Trefoil Trimer Perylenediimide Molecules Probed by Single-Molecule Spectroscopy

    KAUST Repository

    Yoo, Hyejin

    2012-10-25

    Perylenediimide (PDI) molecules are promising building blocks for photophysical studies of electronic interactions within multichromophore arrays. Such PDI arrays are important materials for fabrication of molecular nanodevices such as organic light-emitting diodes, organic semiconductors, and biosensors because of their high photostability, chemical and physical inertness, electron affinity, and high tinctorial strength over the entire visible spectrum. In this work, PDIs have been organized into linear (L3) and trefoil (T3) trimer molecules and investigated by single-molecule fluorescence microscopy to probe the relationship between molecular structures and interchromophoric electronic interactions. We found a broad distribution of coupling strengths in both L3 and T3 and hence strong/weak coupling between PDI units by monitoring spectral peak shifts in single-molecule fluorescence spectra upon sequential photobleaching of each constituent chromophore. In addition, we used a wide-field defocused imaging technique to resolve heterogeneities in molecular structures of L3 and T3 embedded in a PMMA polymer matrix. A systematic comparison between the two sets of experimental results allowed us to infer the correlation between intermolecular interactions and molecular structures. Our results show control of the PDI intermolecular interactions using suitable multichromophoric structures. © 2012 American Chemical Society.

  12. Excitonic Coupling in Linear and Trefoil Trimer Perylenediimide Molecules Probed by Single-Molecule Spectroscopy

    KAUST Repository

    Yoo, Hyejin; Furumaki, Shu; Yang, Jaesung; Lee, Ji-Eun; Chung, Heejae; Oba, Tatsuya; Kobayashi, Hiroyuki; Rybtchinski, Boris; Wilson, Thea M.; Wasielewski, Michael R.; Vacha, Martin; Kim, Dongho

    2012-01-01

    Perylenediimide (PDI) molecules are promising building blocks for photophysical studies of electronic interactions within multichromophore arrays. Such PDI arrays are important materials for fabrication of molecular nanodevices such as organic light-emitting diodes, organic semiconductors, and biosensors because of their high photostability, chemical and physical inertness, electron affinity, and high tinctorial strength over the entire visible spectrum. In this work, PDIs have been organized into linear (L3) and trefoil (T3) trimer molecules and investigated by single-molecule fluorescence microscopy to probe the relationship between molecular structures and interchromophoric electronic interactions. We found a broad distribution of coupling strengths in both L3 and T3 and hence strong/weak coupling between PDI units by monitoring spectral peak shifts in single-molecule fluorescence spectra upon sequential photobleaching of each constituent chromophore. In addition, we used a wide-field defocused imaging technique to resolve heterogeneities in molecular structures of L3 and T3 embedded in a PMMA polymer matrix. A systematic comparison between the two sets of experimental results allowed us to infer the correlation between intermolecular interactions and molecular structures. Our results show control of the PDI intermolecular interactions using suitable multichromophoric structures. © 2012 American Chemical Society.

  13. Probing physics beyond the standard model in diatomic molecules

    International Nuclear Information System (INIS)

    Denis, M.

    2017-01-01

    Nowadays, the incompleteness of the Standard Model of particles (SM) is largely acknowledged. One of its most obvious shortcomings is the lack of explanation for the huge surplus of matter over antimatter in the universe, the so-called baryon asymmetry of the universe. New CP (charge conjugation and spatial parity) violations absent in the SM are assumed to be responsible for this asymmetry. Such a violation could be observed, in ordinary matter through a set of interactions violating both parity and time-reversal symmetries (P, T -odd) among which the preponderant ones are the electron Electric Dipole Moment (eEDM), the electron-nucleon scalar-pseudoscalar (enSPS) and the nuclear magnetic quadrupole moment (nMQM) interactions. Hence, an experimental evidence of a non-zero P, T -odd interaction constant would be a probe of this New Physics beyond the Standard Model. The calculation of the corresponding molecular parameters is performed by making use of an elaborate four-component relativistic configuration interaction approach in polar diatomic molecules containing an actinide, that are particularly adequate systems for eEDM experiments, such as ThO that allowed for assigning the most constraining upper bound on the eEDM and ThF"+ that will be used in a forthcoming experiment. Those results will be of crucial importance in the interpretation of the measurements since the fundamental constants can only be evaluated if one combines both experimental energy shift measurements and theoretical molecular parameters. This manuscript proceeds as follows, after an introduction to the general background of the search of CP-violations and its consequences for the understanding of the Universe (Chapter 1), a presentation of the underlying theory of the evidence of such violation in ordinary matter, namely the P, T -odd sources of the Electric Dipole Moment of a many-electron system, as well as the relevant molecular parameters is given in Chapter 2. A similar introduction to

  14. Mass amplifying probe for sensitive fluorescence anisotropy detection of small molecules in complex biological samples.

    Science.gov (United States)

    Cui, Liang; Zou, Yuan; Lin, Ninghang; Zhu, Zhi; Jenkins, Gareth; Yang, Chaoyong James

    2012-07-03

    Fluorescence anisotropy (FA) is a reliable and excellent choice for fluorescence sensing. One of the key factors influencing the FA value for any molecule is the molar mass of the molecule being measured. As a result, the FA method with functional nucleic acid aptamers has been limited to macromolecules such as proteins and is generally not applicable for the analysis of small molecules because their molecular masses are relatively too small to produce observable FA value changes. We report here a molecular mass amplifying strategy to construct anisotropy aptamer probes for small molecules. The probe is designed in such a way that only when a target molecule binds to the probe does it activate its binding ability to an anisotropy amplifier (a high molecular mass molecule such as protein), thus significantly increasing the molecular mass and FA value of the probe/target complex. Specifically, a mass amplifying probe (MAP) consists of a targeting aptamer domain against a target molecule and molecular mass amplifying aptamer domain for the amplifier protein. The probe is initially rendered inactive by a small blocking strand partially complementary to both target aptamer and amplifier protein aptamer so that the mass amplifying aptamer domain would not bind to the amplifier protein unless the probe has been activated by the target. In this way, we prepared two probes that constitute a target (ATP and cocaine respectively) aptamer, a thrombin (as the mass amplifier) aptamer, and a fluorophore. Both probes worked well against their corresponding small molecule targets, and the detection limits for ATP and cocaine were 0.5 μM and 0.8 μM, respectively. More importantly, because FA is less affected by environmental interferences, ATP in cell media and cocaine in urine were directly detected without any tedious sample pretreatment. Our results established that our molecular mass amplifying strategy can be used to design aptamer probes for rapid, sensitive, and selective

  15. Optical probing of single fluorescent molecules and proteins

    NARCIS (Netherlands)

    Garcia Parajo, M.F.; Veerman, J.A.; Bouwhuis, R.; Bouwhuis, Rudo; van Hulst, N.F.; Vallée, R.A.L.

    2001-01-01

    Single-molecule detection and analysis of organic fluorescent molecules and proteins are presented, with emphasis o­n the underlying principles methodology and the application of single-molecule analysis at room temperature. This Minireview is mainly focused o­n the application of confocal and

  16. Spectroscopic probes of vibrationally excited molecules at chemically significant energies

    Energy Technology Data Exchange (ETDEWEB)

    Rizzo, T.R. [Univ. of Rochester, NY (United States)

    1993-12-01

    This project involves the application of multiple-resonance spectroscopic techniques for investigating energy transfer and dissociation dynamics of highly vibrationally excited molecules. Two major goals of this work are: (1) to provide information on potential energy surfaces of combustion related molecules at chemically significant energies, and (2) to test theoretical modes of unimolecular dissociation rates critically via quantum-state resolved measurements.

  17. Single Molecules as Optical Probes for Structure and Dynamics

    Science.gov (United States)

    Orrit, Michel

    Single molecules and single nanoparticles are convenient links between the nanoscale world and the laboratory. We discuss the limits for their optical detection by three different methods: fluorescence, direct absorption, and photothermal detection. We briefly review some recent illustrations of qualitatively new information gathered from single-molecule signals: intermittency of the fluorescence intensity, acoustic vibrations of nanoparticles (1-100 GHz) or of extended defects in molecular crystals (0.1-1 MHz), and dynamical heterogeneity in glass-forming molecular liquids. We conclude with an outlook of future uses of single-molecule methods in physical chemistry, soft matter, and material science.

  18. Pump-probe study of the formation of rubidium molecules by ultrafast photoassociation of ultracold atoms

    Science.gov (United States)

    McCabe, David J.; England, Duncan G.; Martay, Hugo E. L.; Friedman, Melissa E.; Petrovic, Jovana; Dimova, Emiliya; Chatel, Béatrice; Walmsley, Ian A.

    2009-09-01

    An experimental pump-probe study of the photoassociative creation of translationally ultracold rubidium molecules is presented together with numerical simulations of the process. The formation of loosely bound excited-state dimers is observed as a first step toward a fully coherent pump-dump approach to the stabilization of Rb2 into its lowest ground vibrational states. The population that contributes to the pump-probe process is characterized and found to be distinct from a background population of preassociated molecules.

  19. Facile, novel two-step syntheses of benzimidazoles, bis-benzimidazoles, and bis-benzimidazole-dihydroquinoxalines.

    Science.gov (United States)

    Xu, Zhigang; Shaw, Arthur Y; Dietrich, Justin; Cappelli, Alexandra P; Nichol, Gary; Hulme, Christopher

    2012-02-01

    Three scaffolds of benzimidazoles, bis-benzimidazoles, and bis-benzimidazole-dihydroquinoxalines were synthesized via Ugi/de-protection/cyclization methodology. Benzimidazole forming ring closure was enabled under microwave irradiation in the presence of 10% TFA/DCE. The methodology demonstrates the utility of 2-(N-Boc-amino)-phenyl-isocyanide for the generation of new molecular diversity.

  20. Facile, novel two-step syntheses of benzimidazoles, bis-benzimidazoles, and bis-benzimidazole-dihydroquinoxalines

    OpenAIRE

    Xu, Zhigang; Shaw, Arthur Y.; Dietrich, Justin; Cappelli, Alexandra P.; Nichol, Gary; Hulme, Christopher

    2012-01-01

    Three scaffolds of benzimidazoles, bis-benzimidazoles, and bis-benzimidazole-dihydroquinoxalines were synthesized via Ugi/de-protection/cyclization methodology. Benzimidazole forming ring closure was enabled under microwave irradiation in the presence of 10% TFA/DCE. The methodology demonstrates the utility of 2-(N-Boc-amino)-phenyl-isocyanide for the generation of new molecular diversity.

  1. A subnanomolar fluorescent probe for protein kinase CK2 interaction studies

    DEFF Research Database (Denmark)

    Enkvist, Erki; Viht, Kaido; Bischoff, Nils

    2012-01-01

    of the functions of CK2 could be facilitated by the application of small-molecule fluorescent probes that bind to the active site of the enzyme with high affinity and selectivity. We have used a bisubstrate approach for the development of a highly potent inhibitor of CK2. 4,5,6,7-Tetrabromo-1H-benzimidazole...

  2. Probe Microscopic Studies of DNA Molecules on Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Kazuo Umemura

    2016-10-01

    Full Text Available Hybrids of DNA and carbon nanotubes (CNTs are promising nanobioconjugates for nanobiosensors, carriers for drug delivery, and other biological applications. In this review, nanoscopic characterization of DNA-CNT hybrids, in particular, characterization by scanning probe microscopy (SPM, is summarized. In many studies, topographical imaging by atomic force microscopy has been performed. However, some researchers have demonstrated advanced SPM operations in order to maximize its unique and valuable functions. Such sophisticated approaches are attractive and will have a significant impact on future studies of DNA-CNT hybrids.

  3. ASDB: a resource for probing protein functions with small molecules.

    Science.gov (United States)

    Liu, Zhihong; Ding, Peng; Yan, Xin; Zheng, Minghao; Zhou, Huihao; Xu, Yuehua; Du, Yunfei; Gu, Qiong; Xu, Jun

    2016-06-01

    : Identifying chemical probes or seeking scaffolds for a specific biological target is important for protein function studies. Therefore, we create the Annotated Scaffold Database (ASDB), a computer-readable and systematic target-annotated scaffold database, to serve such needs. The scaffolds in ASDB were derived from public databases including ChEMBL, DrugBank and TCMSP, with a scaffold-based classification approach. Each scaffold was assigned with an InChIKey as its unique identifier, energy-minimized 3D conformations, and other calculated properties. A scaffold is also associated with drugs, natural products, drug targets and medical indications. The database can be retrieved through text or structure query tools. ASDB collects 333 601 scaffolds, which are associated with 4368 targets. The scaffolds consist of 3032 scaffolds derived from drugs and 5163 scaffolds derived from natural products. For given scaffolds, scaffold-target networks can be generated from the database to demonstrate the relations of scaffolds and targets. ASDB is freely available at http://www.rcdd.org.cn/asdb/with the major web browsers. junxu@biochemomes.com or xujun9@mail.sysu.edu.cn Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. UPAR targeted molecular imaging of cancers with small molecule-based probes.

    Science.gov (United States)

    Ding, Feng; Chen, Seng; Zhang, Wanshu; Tu, Yufeng; Sun, Yao

    2017-10-15

    Molecular imaging can allow the non-invasive characterization and measurement of biological and biochemical processes at the molecular and cellular levels in living subjects. The imaging of specific molecular targets that are associated with cancers could allow for the earlier diagnosis and better treatment of diseases. Small molecule-based probes play prominent roles in biomedical research and have high clinical translation ability. Here, with an emphasis on small molecule-based probes, we review some recent developments in biomarkers, imaging techniques and multimodal imaging in molecular imaging and highlight the successful applications for molecular imaging of cancers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Probing Efimov discrete scaling in an atom-molecule collision

    Science.gov (United States)

    Shalchi, M. A.; Yamashita, M. T.; Hadizadeh, M. R.; Garrido, E.; Tomio, Lauro; Frederico, T.

    2018-01-01

    The discrete Efimov scaling behavior, well known in the low-energy spectrum of three-body bound systems for large scattering lengths (unitary limit), is identified in the energy dependence of an atom-molecule elastic cross section in mass-imbalanced systems. That happens in the collision of a heavy atom with mass mH with a weakly bound dimer formed by the heavy atom and a lighter one with mass mL≪mH . Approaching the heavy-light unitary limit, the s -wave elastic cross section σ will present a sequence of zeros or minima at collision energies following closely the Efimov geometrical law. Our results, obtained with Faddeev calculations and supplemented by a Born-Oppenheimer analysis, open a perspective to detecting the discrete scaling behavior from low-energy scattering data, which is timely in view of the ongoing experiments with ultracold binary mixtures having strong mass asymmetries, such as lithium and cesium or lithium and ytterbium.

  6. Probing Enzyme-Surface Interactions via Protein Engineering and Single-Molecule Techniques

    Science.gov (United States)

    2017-06-26

    SECURITY CLASSIFICATION OF: The overall objective of this research was to exploit protein engineering and fluorescence single-molecule methods to...enhance our understanding of the interaction of proteins and surfaces. Given this objective, the specific aims of this research were to: 1) exploit the...incorporation of unnatural amino acids in proteins to introduce single-molecule probes (i.e., fluorophores for fluorescence resonance energy transfer

  7. ANTIBACTERIAL ACTIVITY OF BENZIMIDAZOLES 2-THIO, 2-AMINODERIVATIVES AND COMPLEXES OF BENZIMIDAZOLES WITH TRANSITIONAL METALS

    Directory of Open Access Journals (Sweden)

    E. I. Mayboroda

    2014-01-01

    Full Text Available The literature data about antibacterial properties of benzimidazole 2-thio-, 2-aminoderivatives and benzimidazole complexes have been generalized and systematized in the review. Today prevention and treatment of diseases caused by microorganisms is an actual problem of modern therapy. Therefore, the search for active molecules, the based on them development of some new, more effective antimicrobial agents is an important task of modern pharmaceutical chemistry. Promising compounds for solving these problems are benzimidazole derivatives. They are available, functionally capable, stable and have a wide spectrum of biological activities (antiviral, anthelmintic, antibacterial, anticancer, antidiabetic.The purpose of this paper is to generalize and systematize information about the antimicrobial action of 2-thio-, 2-amino-substituted benzimidazoles and benzimidazole derivatives complexes with transition metals.These compounds and their complexes with transition metals are active against pathogenic strains Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhimurium, Proteus vulgaris, Bacillus cereus, Micrococcus luteus, Helicobacter рylori and others.

  8. A Pyrene- and Phosphonate-Containing Fluorescent Probe as Guest Molecule in a Host Polymer Matrix

    Directory of Open Access Journals (Sweden)

    Jacqueline Marchand-Brynaert

    2013-02-01

    Full Text Available New host-guest materials have been prepared by incorporation of a home-made organic probe displaying a pyrene motif and a phosphonate function into a regular amphiphilic copolymer. Using powder X-Ray diffraction, photoluminescence and FT-IR spectroscopy, we have been able to study the non-covalent interactions between the host matrix and the guest molecule in the solid state. Interestingly, we have shown that the matrix directs the guest spatial localization and alters its properties. Thanks to the comparison of pyrene vs. N-pyrenylmaleimide derivatives, the influence of the chemical nature of the guest molecules on the non-covalent interactions with the host have been studied. In addition, using polyethylene glycol as a reference host, we have been able to evidence a true matrix effect within our new insertion materials. The phosphonated guest molecule appears to be a novel probe targeting the hydrophilic domain of the host copolymer.

  9. Benzimidazoles: A biologically active compounds

    Directory of Open Access Journals (Sweden)

    Salahuddin

    2017-02-01

    Full Text Available Synthesis of commercially available benzimidazole involves condensation of o-phenylenediamine with formic acid. The most prominent benzimidazole compound in nature is N-riosyldimethylbenzimidazole, which serves as a axial ligand for cobalt in vitamin B12. The benzimidazole and its derivatives play a very important role as a therapeutic agent e.g. antiulcer and anthelmintic drugs. Apart from this the benzimidazole derivatives exhibit pharmacological activities such as antimicrobial, antiviral, anticancer, anti-inflammatory, analgesic, etc. The substituted benzimidazoles are summarized in this review to know about the chemistry as well as pharmacological activities.

  10. 1,5-Disubstituted benzimidazoles that direct cardiomyocyte differentiation from mouse embryonic stem cells.

    Science.gov (United States)

    Okolotowicz, Karl J; Bushway, Paul; Lanier, Marion; Gilley, Cynthia; Mercola, Mark; Cashman, John R

    2015-09-01

    Cardiomyopathy is the leading cause of death worldwide. Despite progress in medical treatments, heart transplantation is one of the only current options for those with infarcted heart muscle. Stem cell differentiation technology may afford cell-based therapeutics that may lead to the generation of new, healthy heart muscle cells from undifferentiated stem cells. Our approach is to use small molecules to stimulate stem cell differentiation. Herein, we describe a novel class of 1,5-disubstituted benzimidazoles that induce differentiation of stem cells into cardiac cells. We report on the evaluation in vitro for cardiomyocyte differentiation and describe structure-activity relationship results that led to molecules with drug-like properties. The results of this study show the promise of small molecules to direct stem cell lineage commitment, to probe signaling pathways and to develop compounds for the stimulation of stem cells to repair damaged heart tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Benzimidazole and imidazole hexachlorocerates

    Energy Technology Data Exchange (ETDEWEB)

    Bayanov, A P; Burylev, B P; Temerdashev, Z A; Gusev, V I [Kubanskij Gosudarstvennyj Univ., Krasnodar (USSR)

    1983-02-01

    The process of hexachlorocerium acid with benzimidazole and imidazole interaction and the reaction products are investigated. The values of thermodynamic characteristics of the hexachlorocerium acid reaction with benzimidazole are equal: ..delta..Gsub(298K)=-16.5+-0.2 kJ/mol, ..delta..Hsub(298K)=-63.6+-0.8 kJ/mol, ..delta..Ssub(298K)=-157+-5 J/mol degrees. By the IR spectroscopy and radiography method the individuality of separated compounds has been found. The thermal stability of compounds is determined. The temperature dependence of splitting off chlorine atom from benzimidazole hexachlorocerate on pressure is investigated. Thermodynamic characteristics and activation energies of the process are calculated.

  12. Benzimidazole and imidazole hexachlorocerates

    International Nuclear Information System (INIS)

    Bayanov, A.P.; Burylev, B.P.; Temerdashev, Z.A.; Gusev, V.I.

    1983-01-01

    The process of hexachlorocerium acid with benzimidazole and imidazole interaction and the reaction products are investigated. The values of thermodynamic characteristics of the hexachlorocerium acid reaction with benzimidazole are equal: ΔGsub(298K)=-16.5+-0.2 kJ/mol, ΔHsub(298K)=-63.6+-0.8 kJ/mol, ΔSsub(298K)=-157+-5 J/mol degrees. By the IR spectroscopy and radiography method the individuality of separated compounds has been found. The thermal stability of compounds is determined. The temperature de-- pendence of splitting off chlorine atom from benzimidazole hexachlorocerate on pressure is investigated. Thermodynamic characteristics and activation energies of the process are calculated

  13. Detection of NASBA amplified bacterial tmRNA molecules on SLICSel designed microarray probes

    Directory of Open Access Journals (Sweden)

    Toome Kadri

    2011-02-01

    Full Text Available Abstract Background We present a comprehensive technological solution for bacterial diagnostics using tmRNA as a marker molecule. A robust probe design algorithm for microbial detection microarray is implemented. The probes were evaluated for specificity and, combined with NASBA (Nucleic Acid Sequence Based Amplification amplification, for sensitivity. Results We developed a new web-based program SLICSel for the design of hybridization probes, based on nearest-neighbor thermodynamic modeling. A SLICSel minimum binding energy difference criterion of 4 kcal/mol was sufficient to design of Streptococcus pneumoniae tmRNA specific microarray probes. With lower binding energy difference criteria, additional hybridization specificity tests on the microarray were needed to eliminate non-specific probes. Using SLICSel designed microarray probes and NASBA we were able to detect S. pneumoniae tmRNA from a series of total RNA dilutions equivalent to the RNA content of 0.1-10 CFU. Conclusions The described technological solution and both its separate components SLICSel and NASBA-microarray technology independently are applicative for many different areas of microbial diagnostics.

  14. Detection of NASBA amplified bacterial tmRNA molecules on SLICSel designed microarray probes

    LENUS (Irish Health Repository)

    Scheler, Ott

    2011-02-28

    Abstract Background We present a comprehensive technological solution for bacterial diagnostics using tmRNA as a marker molecule. A robust probe design algorithm for microbial detection microarray is implemented. The probes were evaluated for specificity and, combined with NASBA (Nucleic Acid Sequence Based Amplification) amplification, for sensitivity. Results We developed a new web-based program SLICSel for the design of hybridization probes, based on nearest-neighbor thermodynamic modeling. A SLICSel minimum binding energy difference criterion of 4 kcal\\/mol was sufficient to design of Streptococcus pneumoniae tmRNA specific microarray probes. With lower binding energy difference criteria, additional hybridization specificity tests on the microarray were needed to eliminate non-specific probes. Using SLICSel designed microarray probes and NASBA we were able to detect S. pneumoniae tmRNA from a series of total RNA dilutions equivalent to the RNA content of 0.1-10 CFU. Conclusions The described technological solution and both its separate components SLICSel and NASBA-microarray technology independently are applicative for many different areas of microbial diagnostics.

  15. Comparative study of the active sites in zeolites by different probe molecules

    Directory of Open Access Journals (Sweden)

    ALINE AUROUX

    2005-03-01

    Full Text Available This review summarizes some of the recently published results concerning the acid sites in the zeolites ZSM-5 and Y studied by temperature-programmed desorption (TPD and adsorption calorimetry using different probe molecules NH3, CO, N2O and n-hexane. For the first time it has been shown that the acid sites in hydrated zeolites are accessible for n-hexane adsorption

  16. X-ray Pump–Probe Investigation of Charge and Dissociation Dynamics in Methyl Iodine Molecule

    Directory of Open Access Journals (Sweden)

    Li Fang

    2017-05-01

    Full Text Available Molecular dynamics is of fundamental interest in natural science research. The capability of investigating molecular dynamics is one of the various motivations for ultrafast optics. We present our investigation of photoionization and nuclear dynamics in methyl iodine (CH3I molecule with an X-ray pump X-ray probe scheme. The pump–probe experiment was realized with a two-mirror X-ray split and delay apparatus. Time-of-flight mass spectra at various pump–probe delay times were recorded to obtain the time profile for the creation of high charge states via sequential ionization and for molecular dissociation. We observed high charge states of atomic iodine up to 29+, and visualized the evolution of creating these high atomic ion charge states, including their population suppression and enhancement as the arrival time of the second X-ray pulse was varied. We also show the evolution of the kinetics of the high charge states upon the timing of their creation during the ionization-dissociation coupled dynamics. We demonstrate the implementation of X-ray pump–probe methodology for investigating X-ray induced molecular dynamics with femtosecond temporal resolution. The results indicate the footprints of ionization that lead to high charge states, probing the long-range potential curves of the high charge states.

  17. Benzimidazole-loaded Halloysite Nanotube as a Smart Coating Application

    Directory of Open Access Journals (Sweden)

    Khairina Azmi Zahidah

    2017-09-01

    Full Text Available Smart coating has been developed for the corrosion control of surfaces exposed to corrosive environment. An important step in development of a smart coating is the successful impregnation of corrosion inhibitor into the nanocontainer as a coating pigment. In this study, halloysite was used as nanocontainer to encapsulate benzimidazole as corrosion inhibitor by vacuum method. FESEM, TEM, FTIR and TGA characterization techniques were used to confirm the loading of halloysite with benzimidazole. FESEM results indicated differences between the morphology of the unloaded-halloysite and benzimidazole loaded-halloysite. TEM results confirmed that benzimidazole molecules are loaded into halloysite. FTIR result revealed there are differences in the absorbance characteristic of peaks between peak number 1000-4000 cm-1 for loaded and unloaded samples. It is seen that the absorbance in the loaded-halloysite is higher than unloaded-halloysite, which confirms quantity/specific functional group of molecules. TGA result showed the temperature of degradation of benzimidazole-loaded HNT was higher than pure HNT. EIS was conducted to examine the protection characteristic of the developed smart coating. From EIS results, of 1, 3, and 6 days of experimental duration, it is seen that the value of coating impedance (Z’ after exposure to 3.5% NaCl environment is very height, 2.460E+07 Ω, which confirm a very good anti corrosion protection characteristic for the developed smart coating. 

  18. Chloroanthraquinone as a grafted probe molecule to investigate grafting yield on carbon powder

    International Nuclear Information System (INIS)

    Le Comte, Annaïg; Brousse, Thierry; Bélanger, Daniel

    2016-01-01

    Spontaneous grafting of chloroanthraquinone (ClAQ) groups on Black Pearls carbon by reduction of the corresponding in-situ generated diazonium cations was successfully achieved. The presence of an halogen atom on the quinone molecule allowed the use of different spectroscopic characterization techniques to determine the accurate quinone content of the modified carbon. Electrochemical characterization highlighted that the presence of chlorine atom on the grafted molecule did not affect the electrochemical response or the grafting reaction efficiency. The amount of ClAQ molecules at the carbon surface after grafting was determined by cyclic voltammetry, together with thermogravimetric analysis coupled mass spectroscopy, X-ray photoelectron spectroscopy and elemental analysis. The ClAQ mass loadings estimated from the four techniques are in very good agreement and confirm that the grafted moieties are all electrochemically active and accessible. Finally, the grafting of quinone-type molecule using the reduction of diazonium cations does not affect the electroactivity of the grafted groups and cyclic voltammetry can be considered as a reliable technique to evaluate the mass loading of grafted quinone groups on porous carbon. Thus ClAQ can be used as a grafted probe molecule to investigate grafting yield on carbon powder, and this approach can be extended to functionalized electrodes used in an increasing number of electrochemical energy storage devices.

  19. Radiation-induced polymerization monitored in situ by time-resolved fluorescence of probe molecules in methyl methacrylate

    International Nuclear Information System (INIS)

    Frahn, Mark S.; Abellon, Ruben D.; Luthjens, Leonard H.; Vermeulen, Martien J.W.; Warman, John M.

    2003-01-01

    A technique is presented for monitoring radiation-induced polymerizations in situ based on the measurement of the fluorescence lifetime of molecular probes dissolved in the polymerizing medium. This method is illustrated with results on methyl methacrylate (MMA) using two fluorogenic probe molecules; N-(2-anthracene)methacrylamide (AnMA) and maleimido-fluoroprobe (MFP), a molecule which has a highly dipolar excited state

  20. Communication: Probing the absolute configuration of chiral molecules at aqueous interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lotze, Stephan, E-mail: lotze@amolf.nl; Versluis, Jan [FOM Institute for Atomic and Molecular Physics, Science Park 104, 1098 XG Amsterdam (Netherlands); Olijve, Luuk L. C.; Schijndel, Luuk van; Milroy, Lech G.; Voets, Ilja K. [Laboratory of Macromolecular and Organic Chemistry, Department of Chemical Engineering and Chemistry, and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Bakker, Huib J., E-mail: bakker@amolf.nl [FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam (Netherlands)

    2015-11-28

    We demonstrate that the enantiomers of chiral macromolecules at an aqueous interface can be distinguished with monolayer sensitivity using heterodyne-detected vibrational sum-frequency generation (VSFG). We perform VSFG spectroscopy with a polarization combination that selectively probes chiral molecular structures. By using frequencies far detuned from electronic resonances, we probe the chiral macromolecular structures with high surface specificity. The phase of the sum-frequency light generated by the chiral molecules is determined using heterodyne detection. With this approach, we can distinguish right-handed and left-handed helical peptides at a water-air interface. We thus show that heterodyne-detected VSFG is sensitive to the absolute configuration of complex, interfacial macromolecules and has the potential to determine the absolute configuration of enantiomers at interfaces.

  1. Probe molecule studies: Active species in alcohol synthesis. Final report, July 1993--July 1994

    Energy Technology Data Exchange (ETDEWEB)

    Blackmond, D.G.; Wender, I.; Oukaci, R.; Wang, Jian

    1994-07-01

    The objectives of this project are to investigate the role(s) of cobalt and copper in constructing the active sites for the formation of higher alcohols from CO/H{sub 2} over the Co-Cu based catalysts by using different reduction treatments and applying selected characterization tools such as TPR, TPD, XRD and XPS as well as to generate mechanistic information on the reaction pathway(s) and key intermediate(s) of higher alcohol synthesis from CO/H{sub 2} over Co-Cu/ZnO catalysts by the approach of in-situ addition of a probe molecule (nitromethane).

  2. Comprehensive Review in Current Developments of Benzimidazole-Based Medicinal Chemistry.

    Science.gov (United States)

    Keri, Rangappa S; Hiremathad, Asha; Budagumpi, Srinivasa; Nagaraja, Bhari Mallanna

    2015-07-01

    The properties of benzimidazole and its derivatives have been studied over more than one hundred years. Benzimidazole derivatives are useful intermediates/subunits for the development of molecules of pharmaceutical or biological interest. Substituted benzimidazole derivatives have found applications in diverse therapeutic areas such as antiulcer, anticancer agents, and anthelmintic species to name just a few. This work systematically gives a comprehensive review in current developments of benzimidazole-based compounds in the whole range of medicinal chemistry as anticancer, antibacterial, antifungal, anti-inflammatory, analgesic agents, anti-HIV, antioxidant, anticonvulsant, antitubercular, antidiabetic, antileishmanial, antihistaminic, antimalarial agents, and other medicinal agents. This review will further be helpful for the researcher on the basis of substitution pattern around the nucleus with an aim to help medicinal chemists for developing an SAR on benzimidazole drugs/compounds. © 2014 John Wiley & Sons A/S.

  3. Recyclization reactions leading to benzimidazoles

    International Nuclear Information System (INIS)

    Mamedov, Vakhid A; Murtazina, Anna M

    2011-01-01

    The published data on the recyclization reactions that afford benzimidazoles are generalized and systematized. Both classical and new methods of benzimidazole synthesis are considered. Attention is focused on the publications over the recent 10-15 years; of the earlier publications, only those unknown to the wide circle of chemists are analyzed.

  4. Recyclization reactions leading to benzimidazoles

    Science.gov (United States)

    Mamedov, Vakhid A.; Murtazina, Anna M.

    2011-05-01

    The published data on the recyclization reactions that afford benzimidazoles are generalized and systematized. Both classical and new methods of benzimidazole synthesis are considered. Attention is focused on the publications over the recent 10-15 years; of the earlier publications, only those unknown to the wide circle of chemists are analyzed.

  5. Virtual reality visual feedback for hand-controlled scanning probe microscopy manipulation of single molecules

    Directory of Open Access Journals (Sweden)

    Philipp Leinen

    2015-11-01

    Full Text Available Controlled manipulation of single molecules is an important step towards the fabrication of single molecule devices and nanoscale molecular machines. Currently, scanning probe microscopy (SPM is the only technique that facilitates direct imaging and manipulations of nanometer-sized molecular compounds on surfaces. The technique of hand-controlled manipulation (HCM introduced recently in Beilstein J. Nanotechnol. 2014, 5, 1926–1932 simplifies the identification of successful manipulation protocols in situations when the interaction pattern of the manipulated molecule with its environment is not fully known. Here we present a further technical development that substantially improves the effectiveness of HCM. By adding Oculus Rift virtual reality goggles to our HCM set-up we provide the experimentalist with 3D visual feedback that displays the currently executed trajectory and the position of the SPM tip during manipulation in real time, while simultaneously plotting the experimentally measured frequency shift (Δf of the non-contact atomic force microscope (NC-AFM tuning fork sensor as well as the magnitude of the electric current (I flowing between the tip and the surface. The advantages of the set-up are demonstrated by applying it to the model problem of the extraction of an individual PTCDA molecule from its hydrogen-bonded monolayer grown on Ag(111 surface.

  6. Virtual reality visual feedback for hand-controlled scanning probe microscopy manipulation of single molecules.

    Science.gov (United States)

    Leinen, Philipp; Green, Matthew F B; Esat, Taner; Wagner, Christian; Tautz, F Stefan; Temirov, Ruslan

    2015-01-01

    Controlled manipulation of single molecules is an important step towards the fabrication of single molecule devices and nanoscale molecular machines. Currently, scanning probe microscopy (SPM) is the only technique that facilitates direct imaging and manipulations of nanometer-sized molecular compounds on surfaces. The technique of hand-controlled manipulation (HCM) introduced recently in Beilstein J. Nanotechnol. 2014, 5, 1926-1932 simplifies the identification of successful manipulation protocols in situations when the interaction pattern of the manipulated molecule with its environment is not fully known. Here we present a further technical development that substantially improves the effectiveness of HCM. By adding Oculus Rift virtual reality goggles to our HCM set-up we provide the experimentalist with 3D visual feedback that displays the currently executed trajectory and the position of the SPM tip during manipulation in real time, while simultaneously plotting the experimentally measured frequency shift (Δf) of the non-contact atomic force microscope (NC-AFM) tuning fork sensor as well as the magnitude of the electric current (I) flowing between the tip and the surface. The advantages of the set-up are demonstrated by applying it to the model problem of the extraction of an individual PTCDA molecule from its hydrogen-bonded monolayer grown on Ag(111) surface.

  7. Development and Synthesis of DNA-Encoded Benzimidazole Library.

    Science.gov (United States)

    Ding, Yun; Chai, Jing; Centrella, Paolo A; Gondo, Chenaimwoyo; DeLorey, Jennifer L; Clark, Matthew A

    2018-04-25

    Encoded library technology (ELT) is an effective approach to the discovery of novel small-molecule ligands for biological targets. A key factor for the success of the technology is the chemical diversity of the libraries. Here we report the development of DNA-conjugated benzimidazoles. Using 4-fluoro-3-nitrobenzoic acid as a key synthon, we synthesized a 320 million-member DNA-encoded benzimidazole library using Fmoc-protected amino acids, amines and aldehydes as diversity elements. Affinity selection of the library led to the discovery of a novel, potent and specific antagonist of the NK3 receptor.

  8. Charge Transport in Metal-Molecule-Metal Junctions Probed by Conducting Atomic Force Microscopy

    International Nuclear Information System (INIS)

    Lee, Min Hyung; Song, Hyunwook

    2013-01-01

    We have demonstrated a proof of intrinsic charge transport properties in alkanedithiol molecular junctions using a multiprobe approach combining a variety of transport techniques. The temperature-independent I(V) behavior and the correct exponential decay of conductance with respect to molecular length shows that the dominant charge transport mechanism is off-resonant tunneling. Length-dependent TVS measurements for the saturated alkane-dithiol series indicate that we did indeed probe a molecular system with CAFM. These results can provide stringent criteria to establish a valid molecular transport junction via a probabilistic measurement technique. In this study, we report a study of charge transport in alkanedithiol SAMs formed in metal-molecule-metal junctions using CAFM in combination with a variety of molecular transport techniques including temperature-and length-variable transport measurements and transition voltage spectroscopy. The main goal of this study is to probe the intrinsic transport properties of component molecules using CAFM, but not parasitic or defect-related effects

  9. Precise Orientation of a Single C60 Molecule on the Tip of a Scanning Probe Microscope

    Science.gov (United States)

    Chiutu, C.; Sweetman, A. M.; Lakin, A. J.; Stannard, A.; Jarvis, S.; Kantorovich, L.; Dunn, J. L.; Moriarty, P.

    2012-06-01

    We show that the precise orientation of a C60 molecule which terminates the tip of a scanning probe microscope can be determined with atomic precision from submolecular contrast images of the fullerene cage. A comparison of experimental scanning tunneling microscopy data with images simulated using computationally inexpensive Hückel theory provides a robust method of identifying molecular rotation and tilt at the end of the probe microscope tip. Noncontact atomic force microscopy resolves the atoms of the C60 cage closest to the surface for a range of molecular orientations at tip-sample separations where the molecule-substrate interaction potential is weakly attractive. Measurements of the C60C60 pair potential acquired using a fullerene-terminated tip are in excellent agreement with theoretical predictions based on a pairwise summation of the van der Waals interactions between C atoms in each cage, i.e., the Girifalco potential [L. Girifalco, J. Phys. Chem. 95, 5370 (1991)JPCHAX0022-365410.1021/j100167a002].

  10. Synthesis of ruthenium (III) complexes with benzimidazole derivatives

    International Nuclear Information System (INIS)

    Vyas, P.C.; Chahar, Yogesh K.; Garg, Yajula; Seth, Gita

    2003-01-01

    Complexes of ruthenium with biologically important benzimidazole derivatives, viz. 2-(2'-hydroxyphenyl) benzimidazole (HOPBI), 2-2'- mercaptophenyl) benzimidazole (HSPBI), 2- (2'-hydroxynaphthyl) benzimidazole (HONBI) have been synthesized and characterized. (author)

  11. Probing Protein Multidimensional Conformational Fluctuations by Single-Molecule Multiparameter Photon Stamping Spectroscopy

    Science.gov (United States)

    2015-01-01

    Conformational motions of proteins are highly dynamic and intrinsically complex. To capture the temporal and spatial complexity of conformational motions and further to understand their roles in protein functions, an attempt is made to probe multidimensional conformational dynamics of proteins besides the typical one-dimensional FRET coordinate or the projected conformational motions on the one-dimensional FRET coordinate. T4 lysozyme hinge-bending motions between two domains along α-helix have been probed by single-molecule FRET. Nevertheless, the domain motions of T4 lysozyme are rather complex involving multiple coupled nuclear coordinates and most likely contain motions besides hinge-bending. It is highly likely that the multiple dimensional protein conformational motions beyond the typical enzymatic hinged-bending motions have profound impact on overall enzymatic functions. In this report, we have developed a single-molecule multiparameter photon stamping spectroscopy integrating fluorescence anisotropy, FRET, and fluorescence lifetime. This spectroscopic approach enables simultaneous observations of both FRET-related site-to-site conformational dynamics and molecular rotational (or orientational) motions of individual Cy3-Cy5 labeled T4 lysozyme molecules. We have further observed wide-distributed rotational flexibility along orientation coordinates by recording fluorescence anisotropy and simultaneously identified multiple intermediate conformational states along FRET coordinate by monitoring time-dependent donor lifetime, presenting a whole picture of multidimensional conformational dynamics in the process of T4 lysozyme open-close hinge-bending enzymatic turnover motions under enzymatic reaction conditions. By analyzing the autocorrelation functions of both lifetime and anisotropy trajectories, we have also observed the dynamic and static inhomogeneity of T4 lysozyme multidimensional conformational fluctuation dynamics, providing a fundamental

  12. Radioiodinated benzimidazole derivatives as single photon emission computed tomography probes for imaging of {beta}-amyloid plaques in Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Cui Mengchao [Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501 (Japan); Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Ono, Masahiro, E-mail: ono@pharm.kyoto-u.ac.j [Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501 (Japan); Kimura, Hiroyuki; Kawashima, Hidekazu [Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501 (Japan); Liu Boli [Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Saji, Hideo, E-mail: hsaji@pharm.kyoto-u.ac.j [Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501 (Japan)

    2011-04-15

    Five iodinated 2-phenyl-1H-benzo[d]imidazole derivatives were synthesized and evaluated as potential probes for {beta}-amyloid (A{beta}) plaques. One of the compounds, 4-(6-iodo-1H-benzo[d]imidazol-2-yl)-N,N-dimethylaniline (12), showed excellent affinity for A{beta}{sub 1-42} aggregates (K{sub i}=9.8 nM). Autoradiography with sections of postmortem Alzheimer's disease (AD) brain revealed that a radioiodinated probe [{sup 125}I]12, labeled A{beta} plaques selectively with low nonspecific binding. Biodistribution experiments with normal mice injected intravenously with [{sup 125}I]12 showed high uptake [4.14 percent injected dose per gram (% ID/g) at 2 min] into and rapid clearance (0.15% ID/g at 60 min) from the brain, which may bring about a good signal-to-noise ratio and therefore achieve highly sensitive detection of A{beta} plaques. In addition, [{sup 125}I]12 labeled amyloid plaques in vivo in an AD transgenic model. The preliminary results strongly suggest that [{sup 125}I]12 bears characteristics suitable for detecting amyloid plaques in vivo. When labeled with {sup 123}I, it may be a useful SPECT imaging agent for A{beta} plaques in the brain of living AD patients.

  13. Pump-probe study of atoms and small molecules with laser driven high order harmonics

    Science.gov (United States)

    Cao, Wei

    A commercially available modern laser can emit over 1015 photons within a time window of a few tens of femtoseconds (10-15second), which can be focused into a spot size of about 10 mum, resulting in a peak intensity above 1014W/cm2. This paves the way for table-top strong field physics studies such as above threshold ionization (ATI), non-sequential double ionization (NSDI), high order harmonic generation (HHG), etc.. Among these strong laser-matter interactions, high order harmonic generation, which combines many photons of the fundamental laser field into a single photon, offers a unique way to generate light sources in the vacuum ultraviolet (VUV) or extreme ultraviolet (EUV) region. High order harmonic photons are emitted within a short time window from a few tens of femtoseconds down to a few hundreds of attoseconds (10 -18second). This highly coherent nature of HHG allows it to be synchronized with an infrared (IR) laser pulse, and the pump-probe technique can be adopted to study ultrafast dynamic processes in a quantum system. The major work of this thesis is to develop a table-top VUV(EUV) light source based on HHG, and use it to study dynamic processes in atoms and small molecules with the VUV(EUV)-pump IR-probe method. A Cold Target Recoil Ion Momentum Spectroscopy (COLTRIMS) apparatus is used for momentum imaging of the interaction products. Two types of high harmonic pump pulses are generated and applied for pump-probe studies. The first one consists of several harmonics forming a short attosecond pulse train (APT) in the EUV regime (around 40 eV). We demonstrate that, (1) the auto-ionization process triggered by the EUV in cation carbon-monoxide and oxygen molecules can be modified by scanning the EUV-IR delay, (2) the phase information of quantum trajectories in bifurcated high harmonics can be extracted by performing an EUV-IR cross-correlation experiment, thus disclosing the macroscopic quantum control in HHG. The second type of high harmonic source

  14. Probing symmetry and symmetry breaking in resonant soft-x-ray fluorescence spectra of molecules

    Energy Technology Data Exchange (ETDEWEB)

    Glans, P.; Gunnelin, K.; Guo, J. [Uppsala Univ. (Sweden)] [and others

    1997-04-01

    Conventional non-resonant soft X-ray emission brings about information about electronic structure through its symmetry and polarization selectivity, the character of which is governed by simple dipole rules. For centro-symmetric molecules with the emitting atom at the inversion center these rules lead to selective emission through the required parity change. For the more common classes of molecules which have lower symmetry or for systems with degenerate core orbitals (delocalized over identical sites), it is merely the local symmetry selectivity that provides a probe of the local atomic orbital contribution to the molecular orbital. For instance, in X-ray spectra of first row species the intensities essentially map the p-density at each particular atomic site, and, in a molecular orbital picture, the contribution of the local p-type atomic orbitals in the LCAO description of the molecular orbitals. The situation is different for resonant X-ray fluorescence spectra. Here strict parity and symmetry selectivity gives rise to a strong frequency dependence for all molecules with an element of symmetry. In addition to symmetry selectivity the strong frequency dependence of resonant X-ray emission is caused by the interplay between the shape of a narrow X-ray excitation energy function and the lifetime and vibrational broadenings of the resonantly excited core states. This interplay leads to various observable effects, such as linear dispersion, resonance narrowing and emission line (Stokes) doubling. Also from the point of view of polarization selectivity, the resonantly excited X-ray spectra are much more informative than the corresponding non-resonant spectra. Examples are presented for nitrogen, oxygen, and carbon dioxide molecules.

  15. Photoelectronic characterization of IgG antibody molecule-quantum dot hybrid as biosensing probe

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hye-Weon; Kim, Sung-Jo; Kim, In S [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712 (Korea, Republic of); Lee, Jinwook; Kim, Sungyoun, E-mail: iskim@gist.ac.kr [Center for Seawater Desalination Plant, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712 (Korea, Republic of)

    2010-10-22

    Quantum dot (QD)-based biomolecule hybrids have recently attracted much attention in specifically identifying and labeling target proteins. In this study, QD encapsulated with immunoglobulin antibodies, as a labeling building block in biosensors, was investigated to clarify the most efficient configuration and photoluminescence behavior. Both the biological recognition capacity and photoluminescence emitting signal of the antibody-coupled nanocrystal were validated through a photoelectrical characterization procedure. Derivation of the optimum number of antibody molecules to be packed onto the QD surface yielded the highest binding capacity for the target antigen. During formation of the bioactive layer, the intrinsic photoluminescence response of the QDs significantly decreased due to photoinduced hole transfer according to their rearranged electronic structure. The thorough study of this assembly provides a validation approach for the careful titration of biosensor probes for optimal reaction kinetics. Furthermore, it contributes to the development of an effective tool for the application and interpretation of QD-based labeling techniques.

  16. Photoelectronic characterization of IgG antibody molecule-quantum dot hybrid as biosensing probe

    International Nuclear Information System (INIS)

    Yu, Hye-Weon; Kim, Sung-Jo; Kim, In S; Lee, Jinwook; Kim, Sungyoun

    2010-01-01

    Quantum dot (QD)-based biomolecule hybrids have recently attracted much attention in specifically identifying and labeling target proteins. In this study, QD encapsulated with immunoglobulin antibodies, as a labeling building block in biosensors, was investigated to clarify the most efficient configuration and photoluminescence behavior. Both the biological recognition capacity and photoluminescence emitting signal of the antibody-coupled nanocrystal were validated through a photoelectrical characterization procedure. Derivation of the optimum number of antibody molecules to be packed onto the QD surface yielded the highest binding capacity for the target antigen. During formation of the bioactive layer, the intrinsic photoluminescence response of the QDs significantly decreased due to photoinduced hole transfer according to their rearranged electronic structure. The thorough study of this assembly provides a validation approach for the careful titration of biosensor probes for optimal reaction kinetics. Furthermore, it contributes to the development of an effective tool for the application and interpretation of QD-based labeling techniques.

  17. Assessing subunit dependency of the Plasmodium proteasome using small molecule inhibitors and active site probes.

    Science.gov (United States)

    Li, Hao; van der Linden, Wouter A; Verdoes, Martijn; Florea, Bogdan I; McAllister, Fiona E; Govindaswamy, Kavitha; Elias, Joshua E; Bhanot, Purnima; Overkleeft, Herman S; Bogyo, Matthew

    2014-08-15

    The ubiquitin-proteasome system (UPS) is a potential pathway for therapeutic intervention for pathogens such as Plasmodium, the causative agent of malaria. However, due to the essential nature of this proteolytic pathway, proteasome inhibitors must avoid inhibition of the host enzyme complex to prevent toxic side effects. The Plasmodium proteasome is poorly characterized, making rational design of inhibitors that induce selective parasite killing difficult. In this study, we developed a chemical probe that labels all catalytic sites of the Plasmodium proteasome. Using this probe, we identified several subunit selective small molecule inhibitors of the parasite enzyme complex. Treatment with an inhibitor that is specific for the β5 subunit during blood stage schizogony led to a dramatic decrease in parasite replication while short-term inhibition of the β2 subunit did not affect viability. Interestingly, coinhibition of both the β2 and β5 catalytic subunits resulted in enhanced parasite killing at all stages of the blood stage life cycle and reduced parasite levels in vivo to barely detectable levels. Parasite killing was achieved with overall low host toxicity, something that has not been possible with existing proteasome inhibitors. Our results highlight differences in the subunit dependency of the parasite and human proteasome, thus providing a strategy for development of potent antimalarial drugs with overall low host toxicity.

  18. Thermodynamics of the Sorption of Benzimidazoles on Octadecyl Silica Gel from Water-Methanol Eluents

    Science.gov (United States)

    Shafigulin, R. V.; Bulanova, A. V.

    2018-02-01

    The standard enthalpy and entropy component of transferring benzimidazoles from water-methanol solutions to surfaces of octadecyl silica gel are determined using reversed-phase high-performance liquid chromatography (RP HPLC). The dependences between the enthalpy and polarizability of the molecules of the studied benzimidazoles, the enthalpy and the entropy factor are studied, and the influence of the quantitative composition of the water-methanol solution on the enthalpy are studied.

  19. Infrared-x-ray pump-probe spectroscopy of the NO molecule

    International Nuclear Information System (INIS)

    Guimaraes, F.F.; Felicissimo, V.C.; Kimberg, V.; Gel'mukhanov, F.; Aagren, H.; Cesar, A.

    2005-01-01

    Two color infrared-x-ray pump-probe spectroscopy of the NO molecule is studied theoretically and numerically in order to obtain a deeper insight of the underlying physics and of the potential of this suggested technology. From the theoretical investigation a number of conclusions could be drawn: It is found that the phase of the infrared field strongly influences the trajectory of the nuclear wave packet, and hence, the x-ray spectrum. The trajectory experiences fast oscillations with the vibrational frequency with a modulation due to the anharmonicity of the potential. The dependences of the x-ray spectra on the delay time, the duration, and the shape of the pulses are studied in detail. It is shown that the x-ray spectrum keep memory about the infrared phase after the pump field left the system. This memory effect is sensitive to the time of switching-off the pump field and the Rabi frequency. The phase effect takes maximum value when the duration of the x-ray pulse is one-fourth of the infrared field period, and can be enhanced by a proper control of the duration and intensity of the pump pulse. The manifestation of the phase is different for oriented and disordered molecules and depends strongly on the intensity of the pump radiation

  20. Infrared x-ray pump-probe spectroscopy of the NO molecule

    Science.gov (United States)

    Guimarães, F. F.; Kimberg, V.; Felicíssimo, V. C.; Gel'Mukhanov, F.; Cesar, A.; Ågren, H.

    2005-07-01

    Two color infrared x-ray pump-probe spectroscopy of the NO molecule is studied theoretically and numerically in order to obtain a deeper insight of the underlying physics and of the potential of this suggested technology. From the theoretical investigation a number of conclusions could be drawn: It is found that the phase of the infrared field strongly influences the trajectory of the nuclear wave packet, and hence, the x-ray spectrum. The trajectory experiences fast oscillations with the vibrational frequency with a modulation due to the anharmonicity of the potential. The dependences of the x-ray spectra on the delay time, the duration, and the shape of the pulses are studied in detail. It is shown that the x-ray spectrum keep memory about the infrared phase after the pump field left the system. This memory effect is sensitive to the time of switching-off the pump field and the Rabi frequency. The phase effect takes maximum value when the duration of the x-ray pulse is one-fourth of the infrared field period, and can be enhanced by a proper control of the duration and intensity of the pump pulse. The manifestation of the phase is different for oriented and disordered molecules and depends strongly on the intensity of the pump radiation.

  1. Tautomerism and isomerism in some antitrichinellosis active benzimidazoles: Morphological study in polarized light, quantum chemical computations

    Science.gov (United States)

    Anichina, Kameliya; Mavrova, Anelia; Yancheva, Denitsa; Tsenov, Jordan; Dimitrov, Rasho

    2017-12-01

    The morphology of the crystal structure of some antitrichinellosis active benzimidazole derivatives including (1H-benzimidazol-2-ylthio)acetic acids, [1,3]thiazolo[3,2-a]benzimidazol-3(2H)-ones, 1H-benzimidazol-2-ylthioacetylpiperazines and starting 2-mercapto benzimidazoles, was studied by the use of Polarized Light Microscopy (PLM). Characterization of the crystal phase was complimented by Differential scanning calorimetry analysis (DSC) and spectroscopic data. DFT computations were performed in order to investigate the prototropic tautomerism and the geometry of the molecule of the synthesized compounds. One distinct type of crystal structure for each one of 5 or 6-methyl-(1H-benzimidazol-2-ylthio)acetic acid 6 was observed by PLM - dendritic and needle-shaped formations. Compound 14, containing a methyl substituent in the benzimidazole ring crystallized also into two phases; while for the unsubstituted compound 13 a separation of phases does not take place. The influence of the both solvents - chloroform and ethanol on the phase separation and the formation of the crystalline structure of compound 14 was investigated. The morphological study showed that the cyclization of 6 in the presence of acetic anhydride in pyridine medium led to a mixture of 6-methyl-[1,3]tiazolo[3,2-a]benzimidazol-3(2H)-one (10a) and 7-methyl-[1,3]thiazolo[3,2-a]-benzimidazole-3(2H)-one (10b), which crystallized in the form of fibrils and spherulites respectively. It was found that a difference in the crystal structures of substituted and unsubstituted benzimidazol-2-thiones, respectively benzimidazol-2-thiol derivatives exists, which may be due not only to the thiol-thione tautomerism but to the prototropic properties of the hydrogen atom in first position of the ring. The calculation results indicated that the thione form is more stable than the thiol tautomer by 51-55 kJ mol-1. But at the same time ΔG for the two thiol tautomers is below 0.5 kJ mol-1. In solid phase the 5

  2. Voltammetric Determination of a Benzimidazole Anthelmintic Mixture ...

    African Journals Online (AJOL)

    2002-10-17

    Oct 17, 2002 ... Electrochemistry, square-wave voltammetry, benzimidazole anthelmintics, ... potential application, cathodic reduction/anodic oxidation, the type of the electrode ... benzimidazole anthelmintic in 10 cm3 of methanol-formic acid.

  3. In Silico Mechanistic Profiling to Probe Small Molecule Binding to Sulfotransferases

    Science.gov (United States)

    Martiny, Virginie Y.; Carbonell, Pablo; Lagorce, David; Villoutreix, Bruno O.; Moroy, Gautier; Miteva, Maria A.

    2013-01-01

    Drug metabolizing enzymes play a key role in the metabolism, elimination and detoxification of xenobiotics, drugs and endogenous molecules. While their principal role is to detoxify organisms by modifying compounds, such as pollutants or drugs, for a rapid excretion, in some cases they render their substrates more toxic thereby inducing severe side effects and adverse drug reactions, or their inhibition can lead to drug–drug interactions. We focus on sulfotransferases (SULTs), a family of phase II metabolizing enzymes, acting on a large number of drugs and hormones and showing important structural flexibility. Here we report a novel in silico structure-based approach to probe ligand binding to SULTs. We explored the flexibility of SULTs by molecular dynamics (MD) simulations in order to identify the most suitable multiple receptor conformations for ligand binding prediction. Then, we employed structure-based docking-scoring approach to predict ligand binding and finally we combined the predicted interaction energies by using a QSAR methodology. The results showed that our protocol successfully prioritizes potent binders for the studied here SULT1 isoforms, and give new insights on specific molecular mechanisms for diverse ligands’ binding related to their binding sites plasticity. Our best QSAR models, introducing predicted protein-ligand interaction energy by using docking, showed accuracy of 67.28%, 78.00% and 75.46%, for the isoforms SULT1A1, SULT1A3 and SULT1E1, respectively. To the best of our knowledge our protocol is the first in silico structure-based approach consisting of a protein-ligand interaction analysis at atomic level that considers both ligand and enzyme flexibility, along with a QSAR approach, to identify small molecules that can interact with II phase dug metabolizing enzymes. PMID:24039991

  4. In silico mechanistic profiling to probe small molecule binding to sulfotransferases.

    Directory of Open Access Journals (Sweden)

    Virginie Y Martiny

    Full Text Available Drug metabolizing enzymes play a key role in the metabolism, elimination and detoxification of xenobiotics, drugs and endogenous molecules. While their principal role is to detoxify organisms by modifying compounds, such as pollutants or drugs, for a rapid excretion, in some cases they render their substrates more toxic thereby inducing severe side effects and adverse drug reactions, or their inhibition can lead to drug-drug interactions. We focus on sulfotransferases (SULTs, a family of phase II metabolizing enzymes, acting on a large number of drugs and hormones and showing important structural flexibility. Here we report a novel in silico structure-based approach to probe ligand binding to SULTs. We explored the flexibility of SULTs by molecular dynamics (MD simulations in order to identify the most suitable multiple receptor conformations for ligand binding prediction. Then, we employed structure-based docking-scoring approach to predict ligand binding and finally we combined the predicted interaction energies by using a QSAR methodology. The results showed that our protocol successfully prioritizes potent binders for the studied here SULT1 isoforms, and give new insights on specific molecular mechanisms for diverse ligands' binding related to their binding sites plasticity. Our best QSAR models, introducing predicted protein-ligand interaction energy by using docking, showed accuracy of 67.28%, 78.00% and 75.46%, for the isoforms SULT1A1, SULT1A3 and SULT1E1, respectively. To the best of our knowledge our protocol is the first in silico structure-based approach consisting of a protein-ligand interaction analysis at atomic level that considers both ligand and enzyme flexibility, along with a QSAR approach, to identify small molecules that can interact with II phase dug metabolizing enzymes.

  5. Interaction of Benzimidazoles and Benzotriazole: Its Corrosion Protection Properties on Mild Steel in Hydrochloric Acid

    Science.gov (United States)

    Ramya, K.; Mohan, Revathi; Joseph, Abraham

    2014-11-01

    Synergistic hydrogen-bonded interaction of alkyl benzimidazoles and 1,2,3-benzotrizole and its corrosion protection properties on mild steel in hydrochloric acid at different temperatures have been studied using polarization, EIS, adsorption, surface studies, and computational methods. The extent of synergistic interaction increases with temperature. Quantum chemical approach is used to calculate some electronic properties of the molecules and to ascertain the synergistic interaction, inhibitive effect, and molecular structures. The corrosion inhibition efficiencies and the global chemical reactivity relate to some parameters, such as total energy, E HOMO, E LUMO, and gap energy (Δ E). 1,2,3-Benzotrizole interacts with benzimidazoles derivatives up to a bond length of approximately 1.99 Å. This interaction represents the formation of a hydrogen bond between the 1,2,3-benzotrizole and benzimidazoles. This synergistic interaction of 1,2,3-benzotrizole and benzimidazole derivatives offers extended inhibition efficiency toward mild steel in hydrochloric acid.

  6. A fluorogenic probe for SNAP-tagged plasma membrane proteins based on the solvatochromic molecule Nile Red.

    Science.gov (United States)

    Prifti, Efthymia; Reymond, Luc; Umebayashi, Miwa; Hovius, Ruud; Riezman, Howard; Johnsson, Kai

    2014-03-21

    A fluorogenic probe for plasma membrane proteins based on the dye Nile Red and SNAP-tag is introduced. It takes advantage of Nile Red, a solvatochromic molecule highly fluorescent in an apolar environment, such as cellular membranes, but almost dark in a polar aqueous environment. The probe possesses a tuned affinity for membranes allowing its Nile Red moiety to insert into the lipid bilayer of the plasma membrane, becoming fluorescent, only after its conjugation to a SNAP-tagged plasma membrane protein. The fluorogenic character of the probe was demonstrated for different SNAP-tag fusion proteins, including the human insulin receptor. This work introduces a new approach for generating a powerful turn-on probe for "no-wash" labeling of plasma membrane proteins with numerous applications in bioimaging.

  7. Revival structures of linear molecules in a field-free alignment condition as probed by high-order harmonic generation

    International Nuclear Information System (INIS)

    Lee, G. H.; Kim, H. T.; Park, J. Y.; Nam, C. H.; Kim, T. K.; Lee, J. H.; Ihee, H.

    2006-01-01

    Revival structures (rotational coherence) of three linear molecules (N 2 , O 2 , and CO 2 ) in a field free alignment condition have been investigated using high-order harmonic generation. The harmonic yields of these molecules were measured in a pump-probe manner by using a weak femtosecond (fs) laser pulse for field-free alignment of molecules and another intense fs laser pulse for harmonic generation. The harmonic intensities from 23rd to 29th order with respect to the time delay between the pump and the probe pulses showed revival structures in the condition of a field-free alignment of molecules. While the revival structure of a N 2 molecule had one-fourth the period of the full revival time and different degrees of modulation among different fractional revival times, the revival structures of O 2 and CO 2 molecules showed one-eighth the periods of the full revival time and similar degrees of modulation among all fractional revival times. The revival structures could be interpreted in terms of the nature of the highest occupied molecular orbital and the total nuclear spin.

  8. Single molecule mapping of the optical field distribution of probes for near-field microscopy

    NARCIS (Netherlands)

    Veerman, J.A.; Garcia Parajo, M.F.; Kuipers, L.; van Hulst, N.F.

    1999-01-01

    The most difficult task in near-field scanning optical microscopy (NSOM) is to make a high quality subwavelength aperture probe, Recently we have developed high definition NSOM probes by focused ion beam (FIB) milling. These probes have a higher brightness, better polarization characteristics,

  9. Proposal for probing energy transfer pathway by single-molecule pump-dump experiment

    OpenAIRE

    Tao, Ming-Jie; Ai, Qing; Deng, Fu-Guo; Cheng, Yuan-Chung

    2016-01-01

    The structure of Fenna-Matthews-Olson (FMO) light-harvesting complex has long been recognized as containing seven bacteriochlorophyll (BChl) molecules. Recently, an additional BChl molecule was discovered in the crystal structure of the FMO complex, which may serve as a link between baseplate and the remaining seven molecules. Here, we investigate excitation energy transfer (EET) process by simulating single-molecule pump-dump experiment in the eight-molecules complex. We adopt the coherent m...

  10. Crystal structures and intermolecular interactions of two novel antioxidant triazolyl-benzimidazole compounds

    International Nuclear Information System (INIS)

    Karayel, A.; Özbey, S.; Ayhan-Kılcıgil, G.; Kuş, C.

    2015-01-01

    The crystal structures of 5-(2-(p-chlorophenylbenzimidazol-1-yl-methyl)-4-(3-fluorophenyl)-2, 4-dihydro-[1,2,4]-triazole-3-thione (G6C) and 5-(2-(p-chlorophenylbenzimidazol-1-yl-methyl)-4-(2-methylphenyl)-2, 4-dihydro-[1,2,4]-triazole-3-thione (G4C) have been determined by single-crystal X-ray diffraction. Benzimidazole ring systems in both molecules are planar. The triazole part is almost perpendicular to the phenyl and the benzimidazole parts of the molecules in order to avoid steric interactions between the rings. The crystal structures are stabilized by intermolecular hydrogen bonds between the amino group of the triazole and the nitrogen atom of benzimidazole of a neighboring molecule

  11. Theoretical Investigation of Dynamic Properties of Magnetic Molecule Systems as Probed by NMR and Pulsed Fields Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Rousochatzakis, Ioannis [Iowa State Univ., Ames, IA (United States)

    2005-12-17

    The field of molecular magnetism[l-6] has become a subject of intense theoretical and experimental interest and has rapidly evolved during the last years. This inter-disciplinary field concerns magnetic systems at the molecular or "nanoscopic" level, whose realization has become feasible due to recent advances in the field of chemical synthesis. The present theoretical work provides a first step towards exploiting the possibilities that are offered by probing magnetic molecules using external magnetic fields with high sweep rates. These probes, apart for providing information specific to magnetic molecules, offer the possibility of conducting a detailed study of the relaxational behavior of interacting spin systems as a result of their coupling with a "heat bath" and in particular the excitations of the host lattice. Development of a broad theoretical framework for dealing with relaxational phenomena induced by dynamical magnetic fields is indeed a worthy goal.

  12. Laser action benzimidazoles in various aggregate states

    Energy Technology Data Exchange (ETDEWEB)

    Gruzinskii, V V; Degtiarenko, K M; Shalaev, V K; Kopylova, T N; Verkhovskii, V S; Tarasenko, V F; Melchenko, S V

    1983-04-01

    Lasing has been obtained in solutions of benzimidazole (Bi) derivatives: 2-phenyl-Bi (with the band maximum lambda-r-max 341-347 nm), 2-n-tolyl-Bi (344 nm), and 2-(4'-biphenilyl) Bi (366-374 nm). It is found that compounds of this class provide a basis for laser radiation covering a wide region of the spectrum. Lasing has been obtained on the vapors of 2-(4'-biphenilyl) Bi (361.2 nm) and 2-(n-tolyl) Bi (336.5 nm) with a pentane stabilizer of the excited states. High volatility, photostability, and lasing in wide ranges of concentration determine the efficiency of using this new class of compounds (chain arylbenzimidazoles) in lasers using the vapors of complex molecules.

  13. Laser action benzimidazoles in various aggregate states

    Science.gov (United States)

    Gruzinskii, V. V.; Degtiarenko, K. M.; Shalaev, V. K.; Kopylova, T. N.; Verkhovskii, V. S.; Tarasenko, V. F.; Melchenko, S. V.

    1983-04-01

    Lasing has been obtained in solutions of benzimidazole (Bi) derivatives: 2-phenyl-Bi (with the band maximum lambda-r-max = 341-347 nm), 2-n-tolyl-Bi (344 nm), and 2-(4'-biphenilyl) Bi (366-374 nm). It is found that compounds of this class provide a basis for laser radiation covering a wide region of the spectrum. Lasing has been obtained on the vapors of 2-(4'-biphenilyl) Bi (361.2 nm) and 2-(n-tolyl) Bi (336.5 nm) with a pentane stabilizer of the excited states. High volatility, photostability, and lasing in wide ranges of concentration determine the efficiency of using this new class of compounds (chain arylbenzimidazoles) in lasers using the vapors of complex molecules.

  14. Probing the local environment of a single OPE3 molecule using inelastic tunneling electron spectroscopy

    NARCIS (Netherlands)

    Frisenda, R.; Perrin, M.L.; Van der Zant, H.S.J.

    2015-01-01

    We study single-molecule oligo(phenylene ethynylene)dithiol junctions by means of inelastic electron tunneling spectroscopy (IETS). The molecule is contacted with gold nano-electrodes formed with the mechanically controllable break junction technique. We record the IETS spectrum of the molecule from

  15. Benzimidazoles Pharmacodynamics in Equine Strongyles

    Directory of Open Access Journals (Sweden)

    Laura Catana

    2016-11-01

    Full Text Available Our research aimed to assess the effectiveness of four benzimidazoles: albendazole, fenbendazole, mebendazole and thiabendazole against equine strongyles. The tests were performed between March 2015 and May 2016, on samples collected from 20 horses and 8 donkeys living in Harghita County. In vivo, Faecal Egg Count Reduction Test (FECRT was used to evaluate fenbendazole pharmacodynamics. In vitro, Egg hatch assay (EHA and Larval development assay (LDA were used to evaluate the effectiveness of albendazole, fenbendazole, mebendazole and thiabendazole. The predominance of small strongyle species was observed, mostly Cyathostomum type A. In the horse group, before treatment, the average intensity was 1595.5 EPG, the maximum value being 4000, and extensivity 55%. Tested again at 14 days after treatment, all samples were negative. In the donkey group, before treatment, the total number was 6550 EPG, intensity of 935.7 and extensivity of 87.5%. 14 days after treatment, the average intensity was 150 and the extensivity 50%. In the horse group, EHA proved the efficacy of fenbendazole (0.0192%, albendazole (0.3740% and thiabendazole (11.62% and a major risk of inducing adaptive phenomena for mebendazole (Y parameter 1009.92. In the donkey group, all benzimidazoles had limited effectiveness: thiabendazole (73.93%, mebendazole (87.51%, fenbendazole (94.05%, albendazole (111.67%. All benzimidazoles inhibited larval development. For all tested benzimidazoles, the resistance induction predictive comparative risk analysis highlighted the benefit of their use, provided that the treatment protocol allows sufficient contact time.

  16. Probing the local environment of a single OPE3 molecule using inelastic tunneling electron spectroscopy.

    Science.gov (United States)

    Frisenda, Riccardo; Perrin, Mickael L; van der Zant, Herre S J

    2015-01-01

    We study single-molecule oligo(phenylene ethynylene)dithiol junctions by means of inelastic electron tunneling spectroscopy (IETS). The molecule is contacted with gold nano-electrodes formed with the mechanically controllable break junction technique. We record the IETS spectrum of the molecule from direct current measurements, both as a function of time and electrode separation. We find that for fixed electrode separation the molecule switches between various configurations, which are characterized by different IETS spectra. Similar variations in the IETS signal are observed during atomic rearrangements upon stretching of the molecular junction. Using quantum chemistry calculations, we identity some of the vibrational modes which constitute a chemical fingerprint of the molecule. In addition, changes can be attributed to rearrangements of the local molecular environment, in particular at the molecule-electrode interface. This study shows the importance of taking into account the interaction with the electrodes when describing inelastic contributions to transport through single-molecule junctions.

  17. Laser assisted anticancer activity of benzimidazole based metal organic nanoparticles.

    Science.gov (United States)

    Praveen, P A; Ramesh Babu, R; Balaji, P; Murugadas, A; Akbarsha, M A

    2018-03-01

    Recent studies showed that the photothermal therapy can be effectively used for the targeted cancerous cells destruction. Hence, in the present study, benzimidazole based metal organic complex nanoparticles, dichloro cobalt(II) bis-benzimidazole (Co-BMZ) and dichloro copper(II) bis-benzimidazole (Cu-BMZ), were synthesized by reprecipitation method and their anti-cancer activity by means of photothermal effect has been studied. Transmission electron microscopy analysis shows that the particle size of Cu-BMZ is ∼100 nm and Co-BMZ is in the range between 100 and 400 nm. Zeta potential analysis ensures the stability of the synthesized nanoparticles. It is found that the nonlinear absorption of the nanoparticles increases with increase in laser power intensity. Phototoxicity of human lung cancer (A549) and the normal mouse embryonic fibroblast (NIH-3T3) cells was studied using a 650 nm laser. Even though both the cell lines were affected by laser irradiation, A549 cells show higher cell destruction and lower IC 50 values than the normal cells. Docking studies were used to analyse the interaction site and the results showed that the Cu-BMZ molecules have higher dock score than the Co-BMZ molecules. The obtained results indicate that Cu-BMZ samples have lesser particle size, higher nonlinear absorption and higher interaction energy than the Co-BMZ samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Research on the differences between 2-(2-Chlorophenyl)benzimidazole and 2-(4-Chlorophenyl)benzimidazole based on terahertz time domain spectroscopy

    Science.gov (United States)

    Song, Maojiang; Yang, Fei; Liu, Liping; Shen, Li; Hu, Pengfei; Zhang, Li; Su, Caixia

    2018-05-01

    Due to wide variety of biological and pharmacological activities of benzimidazole derivatives, the differences between 2-(2-Chlorophenyl)benzimidazole and 2-(4-Chlorophenyl) benzimidazole were researched by employing terahertz time-domain spectroscopy and density functional theory systematically. Although the only difference between their molecular configurations is the arrangement of chlorine atom on chlorophenyl ring, there are distinctive differences in their fingerprint spectra in the range of 0.2-2.5 THz, such as amount, amplitude, and frequency position of absorption peaks. The validity of these results was confirmed by the theoretical results simulated by using density functional theory. The possible reasons of these differences originate from the different van der Waals forces and the different dihedral angles of the molecules within crystal cell. These results indicate the importance of this spectral range as a conformational fingerprint region where even minor changes in the molecular configuration lead to major differences in its THz absorption.

  19. Benzimidazoles diminish ERE transcriptional activity and cell growth in breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Payton-Stewart, Florastina [Department of Chemistry, College of Arts and Sciences, Xavier University of Louisiana, New Orleans, LA (United States); Tilghman, Syreeta L. [Division of Basic Pharmaceutical Sciences, College of Pharmacy, Xavier University of Louisiana, New Orleans, LA (United States); Williams, LaKeisha G. [Division of Clinical and Administrative Sciences, College of Pharmacy Xavier University of Louisiana, New Orleans, LA (United States); Winfield, Leyte L., E-mail: lwinfield@spelman.edu [Department of Chemistry, Spelman College, Atlanta, GA (United States)

    2014-08-08

    Highlights: • The methyl-substituted benzimidazole was more effective at inhibiting growth in MDA-MB 231 cells. • The naphthyl-substituted benzimidazole was more effective at inhibiting growth in MCF-7 cells than ICI. • The benzimidazole molecules demonstrated a dose-dependent reduction in ERE transcriptional activity. • The benzimidazole molecules had binding mode in ERα and ERβ comparable to that of the co-crystallized ligand. - Abstract: Estrogen receptors (ERα and ERβ) are members of the nuclear receptor superfamily. They regulate the transcription of estrogen-responsive genes and mediate numerous estrogen related diseases (i.e., fertility, osteoporosis, cancer, etc.). As such, ERs are potentially useful targets for developing therapies and diagnostic tools for hormonally responsive human breast cancers. In this work, two benzimidazole-based sulfonamides originally designed to reduce proliferation in prostate cancer, have been evaluated for their ability to modulate growth in estrogen dependent and independent cell lines (MCF-7 and MDA-MB 231) using cell viability assays. The molecules reduced growth in MCF-7 cells, but differed in their impact on the growth of MDA-MB 231 cells. Although both molecules reduced estrogen response element (ERE) transcriptional activity in a dose dependent manner, the contrasting activity in the MDA-MB-231 cells seems to suggest that the molecules may act through alternate ER-mediated pathways. Further, the methyl analog showed modest selectivity for the ERβ receptor in an ER gene expression array panel, while the naphthyl analog did not significantly alter gene expression. The molecules were docked in the ligand binding domains of the ERα-antagonist and ERβ-agonist crystal structures to evaluate the potential of the molecules to interact with the receptors. The computational analysis complimented the results obtained in the assay of transcriptional activity and gene expression suggesting that the molecules

  20. Benzimidazoles diminish ERE transcriptional activity and cell growth in breast cancer cells

    International Nuclear Information System (INIS)

    Payton-Stewart, Florastina; Tilghman, Syreeta L.; Williams, LaKeisha G.; Winfield, Leyte L.

    2014-01-01

    Highlights: • The methyl-substituted benzimidazole was more effective at inhibiting growth in MDA-MB 231 cells. • The naphthyl-substituted benzimidazole was more effective at inhibiting growth in MCF-7 cells than ICI. • The benzimidazole molecules demonstrated a dose-dependent reduction in ERE transcriptional activity. • The benzimidazole molecules had binding mode in ERα and ERβ comparable to that of the co-crystallized ligand. - Abstract: Estrogen receptors (ERα and ERβ) are members of the nuclear receptor superfamily. They regulate the transcription of estrogen-responsive genes and mediate numerous estrogen related diseases (i.e., fertility, osteoporosis, cancer, etc.). As such, ERs are potentially useful targets for developing therapies and diagnostic tools for hormonally responsive human breast cancers. In this work, two benzimidazole-based sulfonamides originally designed to reduce proliferation in prostate cancer, have been evaluated for their ability to modulate growth in estrogen dependent and independent cell lines (MCF-7 and MDA-MB 231) using cell viability assays. The molecules reduced growth in MCF-7 cells, but differed in their impact on the growth of MDA-MB 231 cells. Although both molecules reduced estrogen response element (ERE) transcriptional activity in a dose dependent manner, the contrasting activity in the MDA-MB-231 cells seems to suggest that the molecules may act through alternate ER-mediated pathways. Further, the methyl analog showed modest selectivity for the ERβ receptor in an ER gene expression array panel, while the naphthyl analog did not significantly alter gene expression. The molecules were docked in the ligand binding domains of the ERα-antagonist and ERβ-agonist crystal structures to evaluate the potential of the molecules to interact with the receptors. The computational analysis complimented the results obtained in the assay of transcriptional activity and gene expression suggesting that the molecules

  1. Functionalization of Probe Tips and Supports for Single-Molecule Recognition Force Microscopy

    Science.gov (United States)

    Ebner, Andreas; Wildling, Linda; Zhu, Rong; Rankl, Christian; Haselgrübler, Thomas; Hinterdorfer, Peter; Gruber, Hermann J.

    The measuring tip of a force microscope can be converted into a monomolecular sensor if one or few "ligand" molecules are attached to the apex of the tip while maintaining ligand function. Functionalized tips are used to study fine details of receptor-ligand interaction by force spectroscopy or to map cognate "receptor" molecules on the sample surface. The receptor (or target) molecules can be present on the surface of a biological specimen; alternatively, soluble target molecules must be immobilized on ultraflat supports. This review describes the methods of tip functionalization, as well as target molecule immobilization. Silicon nitride tips, silicon chips, and mica have usually been functionalized in three steps: (1) aminofunctionalization, (2) crosslinker attachment, and (3) ligand/receptor coupling, whereby numerous crosslinkers are available to couple widely different ligand molecules. Gold-covered tips and/or supports have usually been coated with a self-assembled monolayer, on top of which the ligand/receptor molecule has been coupled either directly or via a crosslinker molecule. Apart from these general strategies, many simplified methods have been used for tip and/or support functionalization, even single-step methods such as adsorption or chemisorption being very efficient under suitable circumstances. All methods are described with the same explicitness and critical parameters are discussed. In conclusion, this review should help to find suitable methods for specific problems of tip and support functionalization.

  2. Proposal for probing energy transfer pathway by single-molecule pump-dump experiment

    Science.gov (United States)

    Tao, Ming-Jie; Ai, Qing; Deng, Fu-Guo; Cheng, Yuan-Chung

    2016-06-01

    The structure of Fenna-Matthews-Olson (FMO) light-harvesting complex had long been recognized as containing seven bacteriochlorophyll (BChl) molecules. Recently, an additional BChl molecule was discovered in the crystal structure of the FMO complex, which may serve as a link between baseplate and the remaining seven molecules. Here, we investigate excitation energy transfer (EET) process by simulating single-molecule pump-dump experiment in the eight-molecules complex. We adopt the coherent modified Redfield theory and non-Markovian quantum jump method to simulate EET dynamics. This scheme provides a practical approach of detecting the realistic EET pathway in BChl complexes with currently available experimental technology. And it may assist optimizing design of artificial light-harvesting devices.

  3. 1-[2,2-Bis(1,3-benzimidazol-1-ylmethyl-3-bromopropyl]-1,3-benzimidazole

    Directory of Open Access Journals (Sweden)

    Tai-Bao Wei

    2011-07-01

    Full Text Available The title compound, C26H23BrN6, has been synthesized as a potential ligand for the construction of metal–organic frameworks. The three benzimidazolyl groups present three potential coordination nodes. The dihedral angles between the benzimidazole ring systems are 74.03 (10, 66.49 (9 and 74.09 (9°. The structure contains large voids, which contain highly disordered solvent molecules that may be CH3CH2OH. Since the solvent molecules could not be located, the PLATON/SQUEEZE procedure [Spek (2009. Acta Cryst. D65, 148–155] was used.

  4. Method for accurate determination of dissociation constants of optical ratiometric systems: chemical probes, genetically encoded sensors, and interacting molecules.

    Science.gov (United States)

    Pomorski, Adam; Kochańczyk, Tomasz; Miłoch, Anna; Krężel, Artur

    2013-12-03

    Ratiometric chemical probes and genetically encoded sensors are of high interest for both analytical chemists and molecular biologists. Their high sensitivity toward the target ligand and ability to obtain quantitative results without a known sensor concentration have made them a very useful tool in both in vitro and in vivo assays. Although ratiometric sensors are widely used in many applications, their successful and accurate usage depends on how they are characterized in terms of sensing target molecules. The most important feature of probes and sensors besides their optical parameters is an affinity constant toward analyzed molecules. The literature shows that different analytical approaches are used to determine the stability constants, with the ratio approach being most popular. However, oversimplification and lack of attention to detail results in inaccurate determination of stability constants, which in turn affects the results obtained using these sensors. Here, we present a new method where ratio signal is calibrated for borderline values of intensities of both wavelengths, instead of borderline ratio values that generate errors in many studies. At the same time, the equation takes into account the cooperativity factor or fluorescence artifacts and therefore can be used to characterize systems with various stoichiometries and experimental conditions. Accurate determination of stability constants is demonstrated utilizing four known optical ratiometric probes and sensors, together with a discussion regarding other, currently used methods.

  5. Single DNA molecules as probes for interrogating silica surfaces after various chemical treatments

    International Nuclear Information System (INIS)

    Liu Xia; Wu Zhan; Nie Huagui; Liu Ziling; He Yan; Yeung, E.S.

    2007-01-01

    We examined the adsorption of single YOYO-1-labeled λ-DNA molecules at glass surfaces after treatment with various chemical cleaning methods by using total internal reflection fluorescence microscopy (TIRFM). The characteristics of these surfaces were further assessed using contact angle (CA) measurements and atomic force microscopy (AFM). By recording the real-time dynamic motion of DNA molecules at the liquid/solid interface, subtle differences in adsorption affinities were revealed. The results indicate that the driving force for adsorption of DNA molecules on glass surfaces is mainly hydrophobic interaction. We also found that surface topography plays a role in the adsorption dynamics

  6. Probing force-induced unfolding intermediates of a single staphylococcal nuclease molecule and the effect of ligand binding

    International Nuclear Information System (INIS)

    Ishii, Takaaki; Murayama, Yoshihiro; Katano, Atsuto; Maki, Kosuke; Kuwajima, Kunihiro; Sano, Masaki

    2008-01-01

    Single-molecule manipulation techniques have given experimental access to unfolding intermediates of proteins that are inaccessible in conventional experiments. A detailed characterization of the intermediates is a challenging problem that provides new possibilities for directly probing the energy landscape of proteins. We investigated single-molecule mechanical unfolding of a small globular protein, staphylococcal nuclease (SNase), using atomic force microscopy. The unfolding trajectories of the protein displayed sub-molecular and stochastic behavior with typical lengths corresponding to the size of the unfolded substructures. Our results support the view that the single protein unfolds along multiple pathways as suggested in recent theoretical studies. Moreover, we found the drastic change, caused by the ligand and inhibitor bindings, in the mechanical unfolding dynamics

  7. Total internal reflection sum-frequency generation spectroscopy and dense gold nanoparticles monolayer: a route for probing adsorbed molecules

    International Nuclear Information System (INIS)

    Tourillon, Gerard; Dreesen, Laurent; Volcke, Cedric; Sartenaer, Yannick; Thiry, Paul A; Peremans, Andre

    2007-01-01

    We show that sum-frequency generation spectroscopy performed in the total internal reflection configuration (TIR-SFG) combined with a dense gold nanoparticles monolayer allows us to study, with an excellent signal to noise ratio and high signal to background ratio, the conformation of adsorbed molecules. Dodecanethiol (DDT) was used as probe molecules in order to assess the potentialities of the approach. An enhancement of more than one order of magnitude of the SFG signals arising from the adsorbed species is observed with the TIR geometry compared to the external reflection one while the SFG non-resonant contribution remains the same for both configurations. Although further work is required to fully understand the origin of the SFG process on nanoparticles, our work opens new possibilities for studying nanostructures

  8. Using Force to Probe Single-Molecule Receptor-Cytoskeletal Anchoring Beneath the Surface of a Living Cell

    DEFF Research Database (Denmark)

    Evans, Evan; Kinoshita, Koji

    2007-01-01

    -cytoskeletal unbinding increased exponentially with the level of force, suggesting disruption at a site of single-molecule interaction. Since many important enzymes and signaling molecules are closely associated with a membrane receptor-cytoskeletal linkage, pulling on a receptor could alter interactions among its......The ligation of cell surface receptors often communicates a signal that initiates a cytoplasmic chemical cascade to implement an important cell function. Less well understood is how physical stress applied to a cell surface adhesive bond propagates throughout the cytostructure to catalyze...... or trigger important steps in these chemical processes. Probing the nanoscale impact of pulling on cell surface bonds, we discovered that receptors frequently detach prematurely from the interior cytostructure prior to failure of the exterior adhesive bond [Evans, E., Heinrich, V., Leung, A., and Kinoshita...

  9. “Turn-on” fluorescence probe integrated polymer nanoparticles for sensing biological thiol molecules

    Science.gov (United States)

    Ang, Chung Yen; Tan, Si Yu; Lu, Yunpeng; Bai, Linyi; Li, Menghuan; Li, Peizhou; Zhang, Quan; Selvan, Subramanian Tamil; Zhao, Yanli

    2014-11-01

    A ``turn-on'' thiol-responsive fluorescence probe was synthesized and integrated into polymeric nanoparticles for sensing intracellular thiols. There is a photo-induced electron transfer process in the off state of the probe, and this process is terminated upon the reaction with thiol compounds. Configuration interaction singles (CIS) calculation was performed to confirm the mechanism of this process. A series of sensing studies were carried out, showing that the probe-integrated nanoparticles were highly selective towards biological thiol compounds over non-thiolated amino acids. Kinetic studies were also performed to investigate the relative reaction rate between the probe and the thiolated amino acids. Subsequently, the Gibbs free energy of the reactions was explored by means of the electrochemical method. Finally, the detection system was employed for sensing intracellular thiols in cancer cells, and the sensing selectivity could be further enhanced with the use of a cancer cell-targeting ligand in the nanoparticles. This development paves a path for the sensing and detection of biological thiols, serving as a potential diagnostic tool in the future.

  10. Probing ultrafast carrier tunneling dynamics in individual quantum dots and molecules

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Kai; Bechtold, Alexander; Kaldewey, Timo; Zecherle, Markus; Wildmann, Johannes S.; Bichler, Max; Abstreiter, Gerhard; Finley, Jonathan J. [Walter Schottky Institut and Physik-Department, Technische Universitaet Muenchen, Am Coulombwall 4, 85748, Garching (Germany); Ruppert, Claudia; Betz, Markus [Experimentelle Physik 2, TU Dortmund, 44221, Dortmund (Germany); Krenner, Hubert J. [Lehrstuhl fuer Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universitaet Augsburg, Universitaetsstr 1, 86159, Augsburg (Germany); Villas-Boas, Jose M. [Instituto de Fisica, Universidade Federal de Uberlandia, 38400-902, Uberlandia, MG (Brazil)

    2013-02-15

    Ultrafast pump-probe spectroscopy is employed to directly monitor the tunneling of charge carriers from single and vertically coupled quantum dots and probe intra-molecular dynamics. Immediately after resonant optical excitation, several peaks are observed in the pump-probe spectrum arising from Coulomb interactions between the photogenerated charge carriers. The influence of few-Fermion interactions in the photoexcited system and the temporal evolution of the optical response is directly probed in the time domain. In addition, the tunneling times for electrons and holes from the QD nanostructure are independently determined. In polarization resolved measurements, near perfect Pauli-spin blockade is observed in the spin-selective absorption spectrum as well as stimulated emission. While electron and hole tunneling from single quantum dots is shown to be well explained by the WKB formalism, for coupled quantum dots pronounced resonances in the electron tunneling rate are observed arising from elastic and inelastic electron tunneling between the different dots. (copyright 2012 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Synthesis of Some Benzimidazole-substituted Benzotriazoles

    African Journals Online (AJOL)

    NJD

    2-Alkylsubstituted benzimidazoles (3a–h) were prepared from the acid-catalyzed reaction of 4-methyl-1,2-phenylenediamine with corresponding carboxylic acids. Addition of these benzimidazoles to N-chloromethylbenzotriazole in the presence of sodium amide under reflux conditions gave the novel ...

  12. Light fluorous-tagged traceless one-pot synthesis of benzimidazoles facilitated by microwave irradiation.

    Science.gov (United States)

    Tseng, Chih-Chung; Tasi, Cheng-Hsun; Sun, Chung-Ming

    2012-06-01

    A novel protocol for rapid assemble of benzimidazole framework has been demonstrated. This method incorporated with light fluorous-tag provides a convenient method for diversification of benzimidazoles and for easy purification via fluorous solid-phase extraction (F-SPE) in a parallel manner. The key transformation of this study involves in situ reduction of aromatic nitro compound, amide formation, cyclization and aromatization promoted by microwave irradiation in a one-pot fashion. The strategy is envisaged to be applied for the establishment of drug-like small molecule libraries for high throughput screening.

  13. Quinoline Fluorescent Probes for Zinc - from Diagnostic to Therapeutic Molecules in Treating Neurodegenerative Diseases.

    Science.gov (United States)

    Czaplinska, Barbara; Spaczynska, Ewelina; Musiol, Robert

    2018-01-01

    Fluorescent compounds had gained strong attention due to their wide and appealing applications. Microscopic techniques and visualization are good examples among others. Introduction of fluorescent dyes into microbiology opens the possibility to observe tissues, organisms or organelle with exceptional sensitivity and resolution. Probes for detection of biologically relevant metals as zinc, iron or copper seems to be particularly important for drug design and pharmaceutical sciences. Quinoline derivatives are well known for their good metal affinity and wide spectrum of biological activity. In this regard, molecular sensors built on this scaffold may be useful not only as analytical but also as therapeutic agents. In the present review, application of quinoline moiety in designing of novel fluorescent probes for zinc is presented and discussed. Zinc cations are relevant for vast majority of processes and recently attract a great deal of attention for their role in neurodegenerative diseases. Compounds interacting with Zn2+ may be used for early diagnosis of such disorders, for example the Alzheimer disease. Quinoline-based zinc probes may exert some beneficial role in organism acting as theranostic agents. First preliminary drugs for Alzheimer therapy that are based on quinoline moiety are good example of this trend. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Probing Electron-Induced Bond Cleavage at the Single-Molecule Level Using DNA Origami Templates

    DEFF Research Database (Denmark)

    Keller, Adrian Clemens; Bald, Ilko; Rotaru, Alexandru

    2012-01-01

    Low-energy electrons (LEEs) play an important role in nanolithography, atmospheric chemistry, and DNA radiation damage. Previously, the cleavage of specific chemical bonds triggered by LEEs has been demonstrated in a variety of small organic molecules such as halogenated benzenes and DNA nucleoba...

  15. How to probe transverse magnetic anisotropy of a single-molecule magnet by electronic transport?

    Science.gov (United States)

    Misiorny, M.; Burzuri, E.; Gaudenzi, R.; Park, K.; Leijnse, M.; Wegewijs, M.; Paaske, J.; Cornia, A.; van der Zant, H.

    We propose an approach for in-situ determination of the transverse magnetic anisotropy (TMA) of an individual molecule by electronic transport measurements, see Phys. Rev. B 91, 035442 (2015). We study a Fe4 single-molecule magnet (SMM) captured in a gateable junction, a unique tool for addressing the spin in different redox states of a molecule. We show that, due to mixing of the spin eigenstates of the SMM, the TMA significantly manifests itself in transport. We predict and experimentally observe the pronounced intensity modulation of the Coulomb peak amplitude with the magnetic field in the linear-response transport regime, from which the TMA parameter E can be estimated. Importantly, the method proposed here does not rely on the small induced tunnelling effects and, hence, works well at temperatures and electron tunnel broadenings by far exceeding the tunnel splittings and even E itself. We deduce that the TMA for a single Fe4 molecule captured in a junction is substantially larger than the bulk value. Work supported by the Polish Ministry of Science and Education as `Iuventus Plus' project (IP2014 030973) in years 2015-2016.

  16. Probing the Conformational Landscape of DNA Polymerases Using Diffusion-Based Single-Molecule FRET

    NARCIS (Netherlands)

    Hohlbein, J.; Kapanidis, A.N.

    2016-01-01

    Monitoring conformational changes in DNA polymerases using single-molecule Förster resonance energy transfer (smFRET) has provided new tools for studying fidelity-related mechanisms that promote the rejection of incorrect nucleotides before DNA synthesis. In addition to the previously known open

  17. Bis(1-benzyl-1H-benzimidazole-κN3dichloridozinc

    Directory of Open Access Journals (Sweden)

    Rachid Bouhfid

    2014-03-01

    Full Text Available In the title compound, [ZnCl2(C14H12N22], the ZnII atom exhibits a distorted tetrahedral coordination geometry involving two chloride anions and two N-atom donors from 1-benzyl-1H-benzimidazole ligands. In both ligands, the benzyl and benzimidazole rings are nearly perpendicular [dihedral angles = 81.7 (2 and 81.5 (2°]. The two benzimidazole systems are essentially planar [maximum deviations = 0.015 (3 and 0.020 (2 Å] and form a dihedral angle of 78.09 (8°. In the crystal, centrosymmetrically related molecules are linked by pairs of C—H...Cl hydrogen bonds into chains parallel to the a axis.

  18. Effect of substituents on polarizability and hyperpolarizability values of benzimidazole metal complexes

    Energy Technology Data Exchange (ETDEWEB)

    Praveen, P. A.; Babu, R. Ramesh, E-mail: rampap2k@yahoo.co.in [Crystal Growth and Thin films Laboratory, Department of Physics, Bharathidasan University, Tiruchirappalli - 620 024, Tamilnadu (India)

    2016-05-23

    In this report, the polarizability and first and second order hyperpolarizability values of bis benzimidazole Zn(II)-2R and bis benzimidazole Cd(II)-2R complexes, with different electron donating moieties R (R= Cl, Br, I, Acetate) were calculated using time dependent Hartree-Fock (TDHF) formalism embedded in MOPAC2012 package. Further the role of substituents on polarizability and hyperpolarizability values is investigated for the first time by analyzing the frontier molecular orbitals of the complexes with respect to the electronegativity of the substituents. It is found that the increase in electronegativity of the substituents correspondingly increases the energy gap of the molecules, which in turn reduces the polarizability values of both Zn and Cd benzimidazole complexes. Similarly, increase in electronegativity reduces the electric quadrupole moments of both the metal complexes, which in turn reduces the hyperpolarizability values.

  19. Probing strong-field electron-nuclear dynamics of polyatomic molecules using proton motion

    International Nuclear Information System (INIS)

    Markevitch, Alexei N.; Smith, Stanley M.; Levis, Robert J.; Romanov, Dmitri A.

    2007-01-01

    Proton ejection during Coulomb explosion is studied for several structure-related organic molecules (anthracene, anthraquinone, and octahydroanthracene) subjected to 800 nm, 60 fs laser pulses at intensities from 0.50 to 4.0x10 14 W cm -2 . The proton kinetic energy distributions are found to be markedly structure specific. The distributions are bimodal for anthracene and octahydroanthracene and trimodal for anthraquinone. Maximum (cutoff) energies of the distributions range from 50 eV for anthracene to 83 eV for anthraquinone. The low-energy mode (∼10 eV) is most pronounced in octahydroanthracene. The dependence of the characteristic features of the distributions on the laser intensity provides insights into molecular specificity of such strong-field phenomena as (i) nonadiabatic charge localization and (ii) field-mediated restructuring of polyatomic molecules polarized by a strong laser field

  20. Enzymatic production of single-molecule FISH and RNA capture probes.

    Science.gov (United States)

    Gaspar, Imre; Wippich, Frank; Ephrussi, Anne

    2017-10-01

    Arrays of singly labeled short oligonucleotides that hybridize to a specific target revolutionized RNA biology, enabling quantitative, single-molecule microscopy analysis and high-efficiency RNA/RNP capture. Here, we describe a simple and efficient method that allows flexible functionalization of inexpensive DNA oligonucleotides by different fluorescent dyes or biotin using terminal deoxynucleotidyl transferase and custom-made functional group conjugated dideoxy-UTP. We show that (i) all steps of the oligonucleotide labeling-including conjugation, enzymatic synthesis, and product purification-can be performed in a standard biology laboratory, (ii) the process yields >90%, often >95% labeled product with minimal carryover of impurities, and (iii) the oligonucleotides can be labeled with different dyes or biotin, allowing single-molecule FISH, RNA affinity purification, and Northern blot analysis to be performed. © 2017 Gaspar et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  1. Mapping the electrostatic force field of single molecules from high-resolution scanning probe images

    Czech Academy of Sciences Publication Activity Database

    Hapala, Prokop; Švec, Martin; Stetsovych, Oleksandr; van der Heijden, N.J.; Ondráček, Martin; van der Lit, J.; Mutombo, Pingo; Swart, I.; Jelínek, Pavel

    2016-01-01

    Roč. 7, May (2016), 1-8, č. článku 11560. ISSN 2041-1723 R&D Projects: GA MŠk LM2015087; GA ČR(CZ) GC14-16963J Institutional support: RVO:68378271 Keywords : generalized gradient approximation * submolecular resolution * tunneling microscope * chemical-structure * co molecules Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 12.124, year: 2016

  2. Momentum mapping spectrometer for probing the fragmentation dynamics of molecules induced by keV electrons

    International Nuclear Information System (INIS)

    Singh, Raj; Bhatt, Pragya; Yadav, Namita; Shanker, R

    2011-01-01

    We describe a new experimental setup for studying the fragmentation dynamics of molecules induced by the impact of keV electrons using the well-known technique of recoil ion momentum spectroscopy. The apparatus consists of mainly a time- and position-sensitive multi-hit particle detector for ion analysis and a channel electron multiplier detector for detecting the ejected electrons. Different components of the setup and the relevant electronics for data acquisition are described in detail with their working principles. In order to verify the reliable performance of the setup, we have recorded the collision-induced ionic spectra of the CO 2 molecule by the impact of keV electrons. Information about the ion pairs of CO + :O + , C + :O + and O + :O + resulting from dissociative ionizing collisions of 20 and 26 keV electrons with a dilute gaseous target of CO 2 molecules has been obtained. Under conditions of the present experiment, the momentum resolutions of the spectrometer for the combined momenta of CO + and O + ions in the direction of the time-of-flight axis and perpendicular to the direction of an electron beam are found to be 10.0 ± 0.2 and 15.0 ± 0.3 au, respectively

  3. Probing the conductance superposition law in single-molecule circuits with parallel paths.

    Science.gov (United States)

    Vazquez, H; Skouta, R; Schneebeli, S; Kamenetska, M; Breslow, R; Venkataraman, L; Hybertsen, M S

    2012-10-01

    According to Kirchhoff's circuit laws, the net conductance of two parallel components in an electronic circuit is the sum of the individual conductances. However, when the circuit dimensions are comparable to the electronic phase coherence length, quantum interference effects play a critical role, as exemplified by the Aharonov-Bohm effect in metal rings. At the molecular scale, interference effects dramatically reduce the electron transfer rate through a meta-connected benzene ring when compared with a para-connected benzene ring. For longer conjugated and cross-conjugated molecules, destructive interference effects have been observed in the tunnelling conductance through molecular junctions. Here, we investigate the conductance superposition law for parallel components in single-molecule circuits, particularly the role of interference. We synthesize a series of molecular systems that contain either one backbone or two backbones in parallel, bonded together cofacially by a common linker on each end. Single-molecule conductance measurements and transport calculations based on density functional theory show that the conductance of a double-backbone molecular junction can be more than twice that of a single-backbone junction, providing clear evidence for constructive interference.

  4. High-throughput platform assay technology for the discovery of pre-microrna-selective small molecule probes.

    Science.gov (United States)

    Lorenz, Daniel A; Song, James M; Garner, Amanda L

    2015-01-21

    MicroRNAs (miRNA) play critical roles in human development and disease. As such, the targeting of miRNAs is considered attractive as a novel therapeutic strategy. A major bottleneck toward this goal, however, has been the identification of small molecule probes that are specific for select RNAs and methods that will facilitate such discovery efforts. Using pre-microRNAs as proof-of-concept, herein we report a conceptually new and innovative approach for assaying RNA-small molecule interactions. Through this platform assay technology, which we term catalytic enzyme-linked click chemistry assay or cat-ELCCA, we have designed a method that can be implemented in high throughput, is virtually free of false readouts, and is general for all nucleic acids. Through cat-ELCCA, we envision the discovery of selective small molecule ligands for disease-relevant miRNAs to promote the field of RNA-targeted drug discovery and further our understanding of the role of miRNAs in cellular biology.

  5. Small Molecules and Sum Frequency Generation Probes of Nanoparticulate TiO2

    Science.gov (United States)

    Shultz, Mary Jane

    2006-03-01

    Anatase TiO2 is known to photo catalytically mineralize a wide variety of pollutants and pathogens, both airborne and in aqueous solution. One of the major benefits of basing water treatment systems on TiO2 is that it is environmentally benign and so non toxic that it is used as a colorant in creamy salad dressing. The primary impediment to wide spread implementation of a TiO2 based system for water decontamination is that the quantum efficiency in contact with condense phase water is less than 5%. Since the quantum efficiency for destruction of airborne materials is greater than 80%, the potential for increased efficiency is very real. To convert the potential to practice, the oxidation mechanism needs to be more fully understood. We will report on the results of using a nonlinear optical spectroscopy, sum frequency generation (SFG) as an in situ probe of interactions at the TiO2 surface. Results suggest that the dominant oxidation mechanism converts from a direct to an indirect mechanism as the water content (vapor pressure) increases. This presentation will discuss the probe technique as well as the results.

  6. Ionic conducting poly-benzimidazoles

    International Nuclear Information System (INIS)

    Jouanneau, J.

    2006-11-01

    Over the last years, many research works have been focused on new clean energy systems. Hydrogen fuel cell seems to be the most promising one. However, the large scale development of this technology is still limited by some key elements. One of them is the polymer electrolyte membrane 'Nafion' currently used, for which the ratio performance/cost is too low. The investigations we carried out during this thesis work are related to a new class of ionic conducting polymer, the sulfonated poly-benzimidazoles (sPBI). Poly-benzimidazoles (PBI) are aromatic heterocyclic polymers well-known for their excellent thermal and chemical stability. Ionic conduction properties are obtained by having strong acid groups (sulfonic acid SO 3 H) on the macromolecular structure. For that purpose, we first synthesized sulfonated monomers. Their poly-condensation with an appropriate non-sulfonated co-monomer yields to sPBI with sulfonation range from 0 to 100 per cent. Three different sPBI structures were obtained, and verified by appropriate analytical techniques. We also showed that the protocol used for the synthesis resulted in high molecular weights polymers. We prepared ionic conducting membrane by casting sPBI solutions on glass plates. Their properties of stability, water swelling and ionic conductivity were investigated. Surprisingly, the behaviour of sPBI was quite different from the other sulfonated aromatic polymers with same amount of SO 3 H, their stability was much higher, but their water swelling and ionic conductivity were quite low. We attributed these differences to strong ionic interactions between the sulfonic acid groups and the basic benzimidazole groups of our polymers. However, we managed to solve this problem synthesizing very highly sulfonated PBI, obtaining membranes with a good balance between all the properties necessary. (author)

  7. The therapeutic journey of benzimidazoles: a review.

    Science.gov (United States)

    Bansal, Yogita; Silakari, Om

    2012-11-01

    Presence of benzimidazole nucleus in numerous categories of therapeutic agents such as antimicrobials, antivirals, antiparasites, anticancer, anti-inflammatory, antioxidants, proton pump inhibitors, antihypertensives, anticoagulants, immunomodulators, hormone modulators, CNS stimulants as well as depressants, lipid level modulators, antidiabetics, etc. has made it an indispensable anchor for development of new therapeutic agents. Varied substitutents around the benzimidazole nucleus have provided a wide spectrum of biological activities. Importance of this nucleus in some activities like, Angiotensin I (AT(1)) receptor antagonism and proton-pump inhibition is reviewed separately in literature. Even some very short reviews on biological importance of this nucleus are also known in literature. However, owing to fast development of new drugs possessing benzimidazole nucleus many research reports are generated in short span of time. So, there is a need to couple the latest information with the earlier information to understand the current status of benzimidazole nucleus in medicinal chemistry research. In the present review, various derivatives of benzimidazole with different pharmacological activities are described on the basis of substitution pattern around the nucleus with an aim to help medicinal chemists for developing an SAR on benzimidazole derived compounds for each activity. This discussion will further help in the development of novel benzimidazole compounds. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Mixing of alcohol and water molecules studied by neutron probe. Structure and dynamics

    International Nuclear Information System (INIS)

    Yoshida, Koji

    2001-01-01

    Structure of water/alcohol mixing solution was studied by three methods such as an isotope-exchanged neutron scattering method, RISM (Reference Interaction Site Model) integral equation and a neutron spin echo method. The principle of methods, experiments and results were reported. The results of experiments of water/tert-butyl alcohol (TBA) solution by the isotope-exchange neutron scattering method showed TBA molecule associated with each other through end methyl group. Especially this effect was the largest at x TBA = 0.06 and decreased with increasing the concentration of TBA. However, hydrogen bonding of TBA was very rare at x TBA = 0.06. By the partial radial distribution function obtained from RISM integral equation, it indicated that the structure of pure TBA became chain structure by hydrogen bond but changed to the structure contacted directly each hydrophobic group with increasing the concentration of water. Water/2-butoxyethanol (BE) mixing solution was measured by a neutron spin echo method. The activation energy of the diffusion coefficients obtained agreed to the energy of hydrogen bonding. The temperature response of diffusion coefficients showed the inverse of the experimental results obtained by the dynamic light scattering method. The difference between two measurement methods was different time scale and space scale. Namely, the object of the neutron scattering method is nano meter and nano second, but one of light scattering method many times over. It was proved from the above results that there was the cluster consisted of the same kind of molecule in the homogeneous two components solution, but the cluster was not stable and constantly exchanged with molecule, where the production and decay of the cluster is repeated at about nano sec. (S.Y.)

  9. Single Molecule Detection in Living Biological Cells using Carbon Nanotube Optical Probes

    Science.gov (United States)

    Strano, Michael

    2009-03-01

    Nanoscale sensing elements offer promise for single molecule analyte detection in physically or biologically constrained environments. Molecular adsorption can be amplified via modulation of sharp singularities in the electronic density of states that arise from 1D quantum confinement [1]. Single-walled carbon nanotubes (SWNT), as single molecule optical sensors [2-3], offer unique advantages such as photostable near-infrared (n-IR) emission for prolonged detection through biological media, single-molecule sensitivity and, nearly orthogonal optical modes for signal transduction that can be used to identify distinct classes of analytes. Selective binding to the SWNT surface is difficult to engineer [4]. In this lecture, we will briefly review the immerging field of fluorescent diagnostics using band gap emission from SWNT. In recent work, we demonstrate that even a single pair of SWNT provides at least four optical modes that can be modulated to uniquely fingerprint chemical agents by the degree to which they alter either the emission band intensity or wavelength. We validate this identification method in vitro by demonstrating detection and identification of six genotoxic analytes, including chemotherapeutic drugs and reactive oxygen species (ROS), which are spectroscopically differentiated into four distinct classes. We also demonstrate single-molecule sensitivity in detecting hydrogen peroxide, one of the most common genotoxins and an important cellular signal. Finally, we employ our sensing and fingerprinting method of these analytes in real time within live 3T3 cells, demonstrating the first multiplexed optical detection from a nanoscale biosensor and the first label-free tool to optically discriminate between genotoxins. We will also discuss our recent efforts to fabricate biomedical sensors for real time detection of glucose and other important physiologically relevant analytes in-vivo. The response of embedded SWNT in a swellable hydrogel construct to

  10. Solvent additive effects on small molecule crystallization in bulk heterojunction solar cells probed during spin casting

    KAUST Repository

    Pérez, Louis A.

    2013-09-04

    Solvent additive processing can lead to drastic improvements in the power conversion efficiency (PCE) in solution processable small molecule (SPSM) bulk heterojunction solar cells. In situ grazing incidence wide-angle X-ray scattering is used to investigate the kinetics of crystallite formation during and shortly after spin casting. The additive is shown to have a complex effect on structural evolution invoking polymorphism and enhanced crystalline quality of the donor SPSM. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Solvent additive effects on small molecule crystallization in bulk heterojunction solar cells probed during spin casting

    KAUST Repository

    Pé rez, Louis A.; Chou, Kang Wei; Love, John A.; Van Der Poll, Thomas S.; Smilgies, Detlef Matthias; Nguyen, Thuc Quyen; Krä mer, Edward J.; Amassian, Aram; Bazan, Guillermo C.

    2013-01-01

    Solvent additive processing can lead to drastic improvements in the power conversion efficiency (PCE) in solution processable small molecule (SPSM) bulk heterojunction solar cells. In situ grazing incidence wide-angle X-ray scattering is used to investigate the kinetics of crystallite formation during and shortly after spin casting. The additive is shown to have a complex effect on structural evolution invoking polymorphism and enhanced crystalline quality of the donor SPSM. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Translocation of "rod-coil" polymers: probing the structure of single molecules within nanopores.

    Science.gov (United States)

    de Haan, Hendrick W; Slater, Gary W

    2013-01-25

    Using simulation and analytical techniques, we demonstrate that it is possible to extract structural information about biological molecules by monitoring the dynamics as they translocate through nanopores. From Langevin dynamics simulations of polymers exhibiting discrete changes in flexibility (rod-coil polymers), distinct plateaus are observed in the progression towards complete translocation. Characterizing these dynamics via an incremental mean first passage approach, the large steps are shown to correspond to local barriers preventing the passage of the coils while the rods translocate relatively easily. Analytical replication of the results provides insight into the corrugated nature of the free energy landscape as well as the dependence of the effective barrier heights on the length of the coil sections. Narrowing the width of the pore or decreasing the charge on either the rod or the coil segments are both shown to enhance the resolution of structural details. The special case of a single rod confined within a nanopore is also studied. Here, sufficiently long flexible sections attached to either end are demonstrated to act as entropic anchors which can effectively trap the rod within the pore for an extended period of time. Both sets of results suggest new experimental approaches for the control and study of biological molecules within nanopores.

  13. Probing static disorder in Arrhenius kinetics by single-molecule force spectroscopy.

    Science.gov (United States)

    Kuo, Tzu-Ling; Garcia-Manyes, Sergi; Li, Jingyuan; Barel, Itay; Lu, Hui; Berne, Bruce J; Urbakh, Michael; Klafter, Joseph; Fernández, Julio M

    2010-06-22

    The widely used Arrhenius equation describes the kinetics of simple two-state reactions, with the implicit assumption of a single transition state with a well-defined activation energy barrier DeltaE, as the rate-limiting step. However, it has become increasingly clear that the saddle point of the free-energy surface in most reactions is populated by ensembles of conformations, leading to nonexponential kinetics. Here we present a theory that generalizes the Arrhenius equation to include static disorder of conformational degrees of freedom as a function of an external perturbation to fully account for a diverse set of transition states. The effect of a perturbation on static disorder is best examined at the single-molecule level. Here we use force-clamp spectroscopy to study the nonexponential kinetics of single ubiquitin proteins unfolding under force. We find that the measured variance in DeltaE shows both force-dependent and independent components, where the force-dependent component scales with F(2), in excellent agreement with our theory. Our study illustrates a novel adaptation of the classical Arrhenius equation that accounts for the microscopic origins of nonexponential kinetics, which are essential in understanding the rapidly growing body of single-molecule data.

  14. Investigation into organic boron compounds complexing. 25. Triaryl borane complexes with benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Belonovich, M I; Lapkin, I I; Morozova, T L; Okatysheva, L Yu; Rybakova, M N; Yuzhakova, G A [Permskij Gosudarstvennyj Univ. (USSR)

    1984-02-01

    Coordination of organic boron compounds with heterocyclic ligands is studied. Substances containing one molecule of ligand per one molecule of triarylborane are extracted when mixing ether solution of triarylborane and alcohol solution of benzimidazole. Based on IR spectra it is stated that coordination with boron is realized at the expense of pyridine nitrogen atom of imidazole cycle. Dipole momenta are determined for synthesized complexes using Debye method.

  15. Structure of substituted 2-(phenoxy)benzimidazoles

    Science.gov (United States)

    Pavlova, I. S.; Pervova, I. G.; Lipunova, G. N.; Novikova, R. K.; Slepukhin, P. A.; Lipunov, I. N.

    2013-03-01

    The synthesis and X-ray diffraction study of 1-benzyl-2-[2-(5-ethyltetrazole-2-yl)-phenoxy]-1H-benzimidazole and 1-benzyl-2-[2-(5-ethyltetrazole-2-yl)-4-nitrophenoxy]-1H-benzimidazole single crystals have been performed. The oxidative splitting of an azo-hydrazone group of 1-(2-hydroxy-(5-nitro)phenyl)-3-ethyl-5-(benzylbenzimidazolyl)formazans, a break in the C2-N1 bond, the interaction of o-hydroxyl group of aryl fragment with oxygen, and the formation of new 2-(phenoxy)benzimidazoles are found to occur in the presence of perchlorate iron(III).

  16. rac-Dichlorido[3-ethoxy-3-(1-ethyl-1H-benzimidazol-2-yl-2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole]copper(II

    Directory of Open Access Journals (Sweden)

    Robert T. Stibrany

    2013-02-01

    Full Text Available The title complex, [CuCl2(C21H22N4O], contains a bis(benzimidazole unit with a chiral bridgehead C atom that forms part of a tetrahydropyrrole ring fused to one of the benzimidazoles. The chelate angle is 90.45 (9° and the dihedral angle between the essentially planar benzimidazole fragments is 26.68 (9°. The CuII coordination geometry lies approximately midway between tetrahedral and square planar. Overall, each chiral molecule contains six fused rings, and a racemic mixture is formed with symmetry-related enantiomers. In the crystal, C—H...π and C—H...Cl interactions link molecules into a supramolecular chain along the a-axis direction.

  17. Biological Activity and Molecular Structures of Bis(benzimidazole and Trithiocyanurate Complexes

    Directory of Open Access Journals (Sweden)

    Pavel Kopel

    2015-06-01

    Full Text Available 1-(1H-Benzimidazol-2-yl-N-(1H-benzimidazol-2-ylmethylmethanamine (abb and 2-(1H-benzimidazol-2-ylmethylsulfanylmethyl-1H-benzimidazole (tbb have been prepared and characterized by elemental analysis. These bis(benzimidazoles have been further used in combination with trithiocyanuric acid for the preparation of complexes. The crystal and molecular structures of two of them have been solved. Each nickel atom in the structure of trinuclear complex [Ni3(abb3(H2O3(μ-ttc](ClO43·3H2O·EtOH (1, where ttcH3 = trithiocyanuric acid, is coordinated with three N atoms of abb, the N,S donor set of ttc anion and an oxygen of a water molecule. The crystal of [(tbbH2(ttcH22(ttcH3(H2O] (2 is composed of a protonated bis(benzimidazole, two ttcH2 anions, ttcH3 and water. The structure is stabilized by a network of hydrogen bonds. These compounds were primarily synthesized for their potential antimicrobial activity and hence their possible use in the treatment of infections caused by bacteria or yeasts (fungi. The antimicrobial and antifungal activity of the prepared compounds have been evaluated on a wide spectrum of bacterial and yeast strains and clinical specimens isolated from patients with infectious wounds and the best antimicrobial properties were observed in strains after the use of ligand abb and complex 1, when at least 80% growth inhibition was achieved.

  18. Novel benzimidazole derivatives as corrosion inhibitors of mild steel in the acidic media. Part II: Theoretical studies

    International Nuclear Information System (INIS)

    Cao, Ziyi; Tang, Yongming; Cang, Hui; Xu, Jinqiu; Lu, Gang; Jing, Wenheng

    2014-01-01

    Highlights: • Quantum chemical and MD studies of benzimidazole derivatives inhibitors. • Inhibition effectiveness depends on the ability to accept electrons. • Active sites of adsorption are mainly centralized on imidazole rings. • Steric effect results in the non-planar adsorption of BBIA and TBIA. - Abstract: In this paper, the adsorption behavior and inhibition mechanism of 2-aminomethyl benzimidazole (ABI), bis(2-benzimidazolylmethyl) amine (BBIA) and tri-(2-benzimidazolylmethyl) amine (TBIA) on the surface of mild steel were studied by quantum chemical calculations and molecular dynamics (MD) simulations. It was found that the three molecules show the similar ability to donate electrons while the difference in inhibition performance should mainly be attributed to the difference in accepting electrons. MD simulations show that steric effect between the benzimidazole segments significantly affects the adsorptive configurations of the molecules on Fe (1 0 0) surface

  19. Synthesis and Photophysical Characterizations of Thermal -Stable Naphthalene Benzimidazoles

    OpenAIRE

    Erten Ela, Şule; Özçelik, Serdar; Eren, Ersin

    2011-01-01

    Microwave-assisted synthesis, photophysical and electrochemical properties of thermal-stable naphthalene benzimidazoles and naphthalimides are studied in this paper. Microwave-assisted synthesis of naphthalene benzimidazoles provide higher yields than the conventional thermal synthesis. Comparative photophysical properties of naphthalene benzimidazoles and naphthalimides are revealed that conjugation of electron-donating group onto naphthalimide moiety increases fluorescence ...

  20. Organic conjugated small molecule materials based optical probe for rapid, colorimetric and UV-vis spectral detection of phosphorylated protein in placental tissue.

    Science.gov (United States)

    Wang, Yanfang; Yang, Na; Liu, Yi

    2018-04-05

    A novel organic small molecule with D-Pi-A structure was prepared, which was found to be a promising colorimetric and ratiometric UV-vis spetral probe for detection of phosphorylated proteins with the help of tetravalent zirconium ion. Such optical probe based on chromophore WYF-1 shows a rapid response (within 10s) and high selectivity and sensitivity for phosphorylated proteins, giving distinct colorimetric and ratiometric UV-vis changes at 720 and 560nm. The detection limit for phosphorylated proteins was estimated to be 100nM. In addition, detection of phosphorylated proteins in placental tissue samples with this probe was successfully applied, which indicates that this probe holds great potential for phosphorylated proteins detection. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Activity of cationically substituted bis-benzimidazoles against experimental Pneumocystis carinii pneumonia.

    Science.gov (United States)

    Tidwell, R R; Jones, S K; Naiman, N A; Berger, L C; Brake, W B; Dykstra, C C; Hall, J E

    1993-01-01

    On the basis of a previously observed correlation between the antimicrobial activity and DNA binding strength of dicationic molecules, a series of 10 dicationically substituted bis-benzimidazoles were tested for activity in the rat model of Pneumocystis carinii pneumonia. One of the compounds, 1,4-bis[5-(2-imidazolinyl)-2-benzimidazolyl]butane, was found to be more potent and less toxic than pentamidine. PMID:8215291

  2. Synthesis and photophysical characterizations of thermal-stable naphthalene benzimidazoles.

    Science.gov (United States)

    Erten-Ela, Sule; Ozcelik, Serdar; Eren, Esin

    2011-07-01

    Microwave-assisted synthesis, photophysical and electrochemical properties of thermal-stable naphthalene benzimidazoles and naphthalimides are studied in this paper. Microwave-assisted synthesis of naphthalene benzimidazoles provide higher yields than the conventional thermal synthesis. Comparative photophysical properties of naphthalene benzimidazoles and naphthalimides are revealed that conjugation of electron-donating group onto naphthalimide moiety increases fluorescence quantum yields. Fluorophore-solvent interactions are also investigated using Lippert-Mataga equation for naphthalimides and naphthalene benzimidazoles. Thermal stabilities of naphthalene benzimidazoles are better than naphthalimides due to increased aromaticity. The experimental E(LUMO) levels of naphthalene benzimidazoles are found to be between 3.15 and 3.28 eV. Therefore, naphthalene benzimidazole derivatives consisting of anchoring groups are promising materials in organic dye sensitized solar cells. © Springer Science+Business Media, LLC 2011

  3. Transcription-factor-mediated DNA looping probed by high-resolution, single-molecule imaging in live E. coli cells.

    Directory of Open Access Journals (Sweden)

    Zach Hensel

    Full Text Available DNA looping mediated by transcription factors plays critical roles in prokaryotic gene regulation. The "genetic switch" of bacteriophage λ determines whether a prophage stays incorporated in the E. coli chromosome or enters the lytic cycle of phage propagation and cell lysis. Past studies have shown that long-range DNA interactions between the operator sequences O(R and O(L (separated by 2.3 kb, mediated by the λ repressor CI (accession number P03034, play key roles in regulating the λ switch. In vitro, it was demonstrated that DNA segments harboring the operator sequences formed loops in the presence of CI, but CI-mediated DNA looping has not been directly visualized in vivo, hindering a deep understanding of the corresponding dynamics in realistic cellular environments. We report a high-resolution, single-molecule imaging method to probe CI-mediated DNA looping in live E. coli cells. We labeled two DNA loci with differently colored fluorescent fusion proteins and tracked their separations in real time with ∼40 nm accuracy, enabling the first direct analysis of transcription-factor-mediated DNA looping in live cells. Combining looping measurements with measurements of CI expression levels in different operator mutants, we show quantitatively that DNA looping activates transcription and enhances repression. Further, we estimated the upper bound of the rate of conformational change from the unlooped to the looped state, and discuss how chromosome compaction may impact looping kinetics. Our results provide insights into transcription-factor-mediated DNA looping in a variety of operator and CI mutant backgrounds in vivo, and our methodology can be applied to a broad range of questions regarding chromosome conformations in prokaryotes and higher organisms.

  4. Small molecule probes finely differentiate between various ds- and ss-DNA and RNA by fluorescence, CD and NMR response

    Energy Technology Data Exchange (ETDEWEB)

    Crnolatac, Ivo; Rogan, Iva; Majić, Boris; Tomić, Sanja [Division of Organic Chemistry and Biochemistry, Division of Physical Chemistry, Ruđer Bošković Institute, P.O. Box 180, 10002 Zagreb (Croatia); Deligeorgiev, Todor [Faculty of Chemistry and Pharmacy, University of Sofia (Bulgaria); Horvat, Gordan [Department of Physical Chemistry, Faculty of Science/Chemistry, Horvatovac 102A, HR-10000 Zagreb (Croatia); Makuc, Damjan; Plavec, Janez [Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, Ljubljana (Slovenia); EN-FIST Centre of Excellence, Trg Osvobodilne Fronte 13, Ljubljana (Slovenia); Pescitelli, Gennaro [Department of Chemistry, University of Pisa, Via Moruzzi 13, Pisa (Italy); Piantanida, Ivo, E-mail: pianta@irb.hr [Division of Organic Chemistry and Biochemistry, Division of Physical Chemistry, Ruđer Bošković Institute, P.O. Box 180, 10002 Zagreb (Croatia)

    2016-10-12

    Two small molecules showed intriguing properties of analytical multipurpose probes, whereby one chromophore gives different signal for many different DNA/RNA by application of several highly sensitive spectroscopic methods. Dyes revealed pronounced fluorescence ratiomeric differentiation between ds-AU-RNA, AT-DNA and GC-DNA in approximate order 10:8:1. Particularly interesting, dyes showed specific fluorimetric response for poly rA even at 10-fold excess of any other ss-RNA, and moreover such emission selectivity is preserved in multicomponent ss-RNA mixtures. The dyes also showed specific chiral recognition of poly rU in respect to the other ss-RNA by induced CD (ICD) pattern in visible range (400–500 nm), which was attributed to the dye-side-chain contribution to binding (confirmed by absence of any ICD band for reference compound lacking side-chain). Most intriguingly, minor difference in the side-chain attached to dye chromophore resulted in opposite sign of dye-ICD pattern, whereby differences in NMR NOESY contacts and proton chemical shifts between two dye/oligo rU complexes combined with MD simulations and CD calculations attributed observed bisignate ICD to the dimeric dye aggregate within oligo rU. - Highlights: • Novel dyes emit fluorescence only for poly rA even at high excess of all other ss-RNA. • Fluorescence response for AT-DNA is 8 times stronger than for GC-DNA. • Florescence induced by ds-RNA is 20% stronger that emission induced by ds-DNA. • Intrinsically non-chiral, dyes show strong and characteristic ICD response for poly rU.

  5. Thermostability and photophysical properties of mixed-ligand carboxylate/benzimidazole Zn(II)-coordination polymers

    International Nuclear Information System (INIS)

    Barros, Bráulio Silva; Chojnacki, Jaroslaw; Macêdo Soares, Antonia Alice; Kulesza, Joanna; Lourenço da Luz, Leonis; Júnior, Severino Alves

    2015-01-01

    The reaction between Zn(NO 3 ) 2 ·6H 2 O or Zn(CH 3 COO) 2 ·2H 2 O and isophthalic acid (1,3-H 2 bdc) in the presence of benzimidazole (Hbzim) in dimethylformamide (DMF)/ethanol (EtOH)/H 2 O solvent mixture at room temperature yielded two structurally different coordination polymers: [Zn 2 (1,3-bdc) 2 (Hbzim) 2 ] (1) and [Zn 2 (1,3-bdc)(bzim) 2 ] (2). (1) is a 2D-layered framework with a molecule of benzimidazole coordinated to the Zn center, whereas (2) is a 3D framework with benzimidazolate species acting as a co-ligand and bridging two Zn(II) ions. Reactions performed at 90 °C led to the formation of coordination polymers structurally similar to (2), independently of the Zn(II) source used. In the absence of benzimidazole, the reaction between ZnAc 2 .2H 2 O and 1,3-H 2 bdc at 90 °C resulted in the formation of (3), a 3D coordination polymer Zn(HCOO) 3 (Me 2 NH 2 + ). It was observed that the thermostability and the photophysical properties of (1) and (2) are strongly dependent on the coordination modes and packing of benzimidazole in the solid state. These materials present photoluminescence in the wide range of the spectrum, from UV to IR. A full understanding of a physical process occurring in these intriguing systems, including complete energy level diagrams with possible transitions were provided. - Graphical abstract: Display Omitted - Highlights: • Structurally different Zn(II)-coordination polymers were prepared. • The formation of frameworks was counter anion and temperature dependent. • Photoluminescence in the wide range of the spectrum, from UV to IR was observed. • Thermostability and luminescence depended on bzim packing in the structure

  6. Simple, mild, and highly efficient synthesis of 2-substituted benzimidazoles and bis-benzimidazoles

    OpenAIRE

    Eren,Bilge; Bekdemir,Yunus

    2014-01-01

    A new convenient method for preparation of 2-substituted benzimidazoles and bis-benzimidazoles is presented. In this method, o-phenylenediamines were condensed with bisulfite adducts of various aldehydes and di-aldehydes under neat conditions by microwave heating. The results were also compared with results of synthesis by conventional heating under reflux. Structures of the products were confirmed by infrared, ¹H- and 13C-NMR spectroscopy. Short reaction times, good yields, easy purification...

  7. Generation of radiation by benzimidazoles in various aggregate states

    Energy Technology Data Exchange (ETDEWEB)

    Gruzinsky, V V; Degtyarenko, K M; Shalaev, V K; Kopylova, T N; Verkhovsky, V S; Tarasenko, V F; Melochenko, S V

    1983-04-01

    Lasing has been obtained on the solutions of new derivatives of benzimidazole (Bi): 2-phenyl-Bi (the band maximum lambda/sub r.max/ = 341/347 nm), 2-n-tolyl-Bi (344 nm) and 2-(4'-biphenilyl) Bi (366/374 nm). Compounds of this class provide a perspective basis for laser radiation covering of a wide spectrum region. Lasing has been obtained on the vapors of 2-(4'-biphenilyl)Bi (361.2 nm) and 2-(n-tolyl) Bi (336.3 nm) with pentane stabilizer of excited states. High volatility, photostability and laser-action over wide concentration ranges determine the efficiency of using the new class of compounds - chain arylbenzimitazoles - in lasers based on complex molecule vapors.

  8. DNA-Compatible Nitro Reduction and Synthesis of Benzimidazoles.

    Science.gov (United States)

    Du, Huang-Chi; Huang, Hongbing

    2017-10-18

    DNA-encoded chemical libraries have emerged as a cost-effective alternative to high-throughput screening (HTS) for hit identification in drug discovery. A key factor for productive DNA-encoded libraries is the chemical diversity of the small molecule moiety attached to an encoding DNA oligomer. The library structure diversity is often limited to DNA-compatible chemical reactions in aqueous media. Herein, we describe a facile process for reducing aryl nitro groups to aryl amines. The new protocol offers simple operation and circumvents the pyrophoric potential of the conventional method (Raney nickel). The reaction is performed in aqueous solution and does not compromise DNA structural integrity. The utility of this method is demonstrated by the versatile synthesis of benzimidazoles on DNA.

  9. Reaction-based small-molecule fluorescent probes for dynamic detection of ROS and transient redox changes in living cells and small animals.

    Science.gov (United States)

    Lü, Rui

    2017-09-01

    Dynamic detection of transient redox changes in living cells and animals has broad implications for human health and disease diagnosis, because intracellular redox homeostasis regulated by reactive oxygen species (ROS) plays important role in cell functions, normal physiological functions and some serious human diseases (e.g., cancer, Alzheimer's disease, diabetes, etc.) usually have close relationship with the intracellular redox status. Small-molecule ROS-responsive fluorescent probes can act as powerful tools for dynamic detection of ROS and redox changes in living cells and animals through fluorescence imaging techniques; and great advances have been achieved recently in the design and synthesis of small-molecule ROS-responsive fluorescent probes. This article highlights up-to-date achievements in designing and using the reaction-based small-molecule fluorescent probes (with high sensitivity and selectivity to ROS and redox cycles) in the dynamic detection of ROS and transient redox changes in living cells and animals through fluorescence imaging. Copyright © 2017. Published by Elsevier Ltd.

  10. Dibromido[1,1′-dibutyl-2,2′-(pentane-1,1-diyldi-1H-benzimidazole]copper(II

    Directory of Open Access Journals (Sweden)

    Robert T. Stibrany

    2010-07-01

    Full Text Available In the title compound, [CuBr2(C27H36N4], the CuII ion exhibits a distorted tetrahedral coordination geometry provided by two bromide ions and by chelation of two imine N-atom donors from a bis(benzimidazole ligand. Chelation results in a six-membered boat-shaped ring which links the benzimidazole groups. Each bis(benzimidazole fragment contains three n-butyl substituents, two of which have the expected trans conformation; the third exhibits the higher-energy cis conformation, an orientation consistent with several short intramolecular C—H...Br interactions. Essentially planar (r.m.s. deviations of 0.0101 and 0.0183 Å benzimidazole groups are oriented so as to give the bis(benzimidazole fragment a V-shaped appearance in profile with the cis and trans n-butyl groups directed to opposite sides of the planes. In the crystal, columns of molecules along the b-axis direction form layers parallel to the (202 planes. Within a given column, the molecules are linked by C—H...Br hydrogen bonds. The molecules in adjacent columns are also linked by intermolecular C—H...π interactions, forming a three-dimensional network.

  11. Electrons as probes of dynamics in molecules and clusters: A contribution from Time Dependent Density Functional Theory

    International Nuclear Information System (INIS)

    Wopperer, P.; Dinh, P.M.; Reinhard, P.-G.; Suraud, E.

    2015-01-01

    There are various ways to analyze the dynamical response of clusters and molecules to electromagnetic perturbations. Particularly rich information can be obtained from measuring the properties of electrons emitted in the course of the excitation dynamics. Such an analysis of electron signals covers observables such as total ionization, Photo-Electron Spectra (PES), Photoelectron Angular Distributions (PAD), and ideally combined PES/PAD. It has a long history in molecular physics and was increasingly used in cluster physics as well. Recent progress in the design of new light sources (high intensity, high frequency, ultra short pulses) opens new possibilities for measurements and thus has renewed the interest on these observables, especially for the analysis of various dynamical scenarios, well beyond a simple access to electronic density of states. This, in turn, has motivated many theoretical investigations of the dynamics of electronic emission for molecules and clusters up to such a complex and interesting system as C 60 . A theoretical tool of choice is here Time-Dependent Density Functional Theory (TDDFT) propagated in real time and on a spatial grid, and augmented by a Self-Interaction Correction (SIC). This provides a pertinent, robust, and efficient description of electronic emission including the detailed pattern of PES and PAD. A direct comparison between experiments and well founded elaborate microscopic theories is thus readily possible, at variance with more demanding observables such as for example fragmentation or dissociation cross sections. The purpose of this paper is to describe the theoretical tools developed on the basis of real-time and real-space TDDFT and to address in a realistic manner the analysis of electronic emission following irradiation of clusters and molecules by various laser pulses. After a general introduction, we shall present in a second part the available experimental results motivating such studies, starting from the simplest

  12. Facile Synthesis of N -Substituted Benzimidazoles

    NARCIS (Netherlands)

    Kurhade, Santosh; Rossetti, Arianna; Dömling, Alexander

    2016-01-01

    A particularly mild and efficient one-pot synthesis of N-substituted benzimidazole derivatives was developed. 2-Fluoro-5-nitrophenylisocyanide reacts with a diverse set of primary amines to afford the respective products in moderate to very good yield (35-95%; 20 examples).

  13. 2-(4-Hydroxyphenyl-1H-benzimidazol-3-ium chloride monohydrate

    Directory of Open Access Journals (Sweden)

    Jazmin E. González-Padilla

    2013-09-01

    Full Text Available The title molecular salt, C13H11N2O+·Cl−·H2O, crystallizes as a monohydrate. In the cation, the phenol and benzimidazole rings are almost coplanar, making a dihedral angle of 3.18 (4°. The chloride anion and benzimidazole cation are linked by two N+—H...Cl− hydrogen bonds, forming chains propagating along [010]. These chains are linked through O—H...Cl hydrogen bonds involving the water molecule and the chloride anion, which form a diamond core, giving rise to the formation of two-dimensional networks lying parallel to (10-2. Two π–π interactions involving the imidazolium ring with the benzene and phenol rings [centroid–centroid distances = 3.859 (3 and 3.602 (3 Å, respectively], contribute to this second dimension. A strong O—H...O hydrogen bond involving the water molecule and the phenol substituent on the benzimidazole unit links the networks, forming a three-dimensional structure.

  14. Probing the emitter site of Renilla luciferase using small organic molecules; an attempt to understand the molecular architecture of the emitter site.

    Science.gov (United States)

    Salehi, Farajollah; Emamzadeh, Rahman; Nazari, Mahboobeh; Rasa, Seyed Mohammad Mahdi

    2016-12-01

    Renilla luciferase is a sensitive enzyme and has wide applications in biotechnology such as drug screening. Previous studies have tried to show the catalytic residues, nevertheless, the accurate architecture and molecular behavior of its emitter site remains uncharacterized. In this study, the activity of Renilla luciferase, in the presence of two small organic molecules including dimethyl sulfoxide (DMSO) and isopropanol was considered and the structure was studied by circular dichroism (CD) and fluorescence spectroscopy. Moreover, the interaction of small organic molecules with the Renilla luciferase was studied using molecular dynamics simulations. Kinetics studies showed that at low concentration of DMSO (16.6-66mM) and isopropanol (19.3-76mM) the K m changed and a competitive inhibition pattern was observed. Moreover, spectroscopy studies reveled that the changes of activity of Renilla luciferase in the presence of low concentrations of small organic molecules was not associated with structural collapse or severe changes in the enzyme conformation. Molecular dynamics simulations indicated that DMSO and isopropanol, as probing molecules, were both able to bind to the emitter site and remained with the residues of the emitter site. Based on the probing data, the architecture of the emitter site in the "non-binding" model was proposed. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Orthorhombic polymorph of 4-[(1H-benzimidazol-1-ylmethyl]benzoic acid

    Directory of Open Access Journals (Sweden)

    Hai-Wei Kuai

    2011-11-01

    Full Text Available We reported recently the first polymorph of the title compound [Kuai & Cheng (2011a. Acta Cryst., E67, o2787]. A second polymorph of the title compound, C15H12N2O2, was unexpectedly obtained by the hydrothermal reaction of the title compound with manganese chloride in the presence of potassium hydroxide at 413 K. The benzimidazole ring system is almost planar, with a maximum deviation from the mean plane of 0.015 (2 Å. The benzimidazole and benzene rings are inclined at a dihedral angle of 79.00 (1°. In the crystal, adjacent molecules are connected through O—H...N hydrogen bonds into a one-dimensional chain along the [001] direction.

  16. Spektrální vlastnosti benzimidazolů

    OpenAIRE

    Lukešová, Marie

    2010-01-01

    Spectral Properties of Benzimidazoles Marie Lukešová Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Abstract: This diploma thesis deals with the spectral properties of benzimidazoles. Most of benzimidazoles are anthelmintic active drug, used primarily in veterinary medicine. Some substances are used as fungicides. The main aim of this study was to clarify the influence of solvents on the absorption spectra and especially on ...

  17. Subunits of highly Fluorescent Protein R-Phycoerythrin as Probes for Cell Imaging and Single-Molecule Detection

    Energy Technology Data Exchange (ETDEWEB)

    Isailovic, Dragan [Iowa State Univ., Ames, IA (United States)

    2005-01-01

    The purposes of our research were: (1) To characterize subunits of highly fluorescent protein R-Phycoerythrin (R-PE) and check their suitability for single-molecule detection (SMD) and cell imaging, (2) To extend the use of R-PE subunits through design of similar proteins that will be used as probes for microscopy and spectral imaging in a single cell, and (3) To demonstrate a high-throughput spectral imaging method that will rival spectral flow cytometry in the analysis of individual cells. We first demonstrated that R-PE subunits have spectroscopic and structural characteristics that make them suitable for SMD. Subunits were isolated from R-PE by high-performance liquid chromatography (HPLC) and detected as single molecules by total internal reflection fluorescence microscopy (TIRFM). In addition, R-PE subunits and their enzymatic digests were characterized by several separation and detection methods including HPLC, capillary electrophoresis, sodium dodecyl sulfate-polyacrilamide gel electrophoresis (SDS-PAGE) and HPLC-electrospray ionization mass spectrometry (ESI-MS). Favorable absorption and fluorescence of the R-PE subunits and digest peptides originate from phycoerythrobilin (PEB) and phycourobilin (PUB) chromophores that are covalently attached to cysteine residues. High absorption coefficients and strong fluorescence (even under denaturing conditions), broad excitation and emission fluorescence spectra in the visible region of electromagnetic spectrum, and relatively low molecular weights make these molecules suitable for use as fluorescence labels of biomolecules and cells. We further designed fluorescent proteins both in vitro and in vivo (in Escherichia coli) based on the highly specific attachment of PEB chromophore to genetically expressed apo-subunits of R-PE. In one example, apo-alpha and apo-beta R-PE subunits were cloned from red algae Polisiphonia boldii (P. boldii), and expressed in E. coli. Although expressed apo-subunits formed inclusion

  18. Synthesis of Aminofuran-Linked Benzimidazoles and Cyanopyrrole-Fused Benzimidazoles by Condition-Based Skeletal Divergence.

    Science.gov (United States)

    Hsu, Wei-Shun; Tsai, Min-Huan; Barve, Indrajeet J; Yellol, Gorakh S; Sun, Chung-Ming

    2017-07-10

    A condition-based skeletal divergent synthesis was explored to achieve skeletal diversity in two component condensation reaction. Cyanomethyl benzimidazole was reacted with α-bromoketone under thermal conditions to furnish 2-aminofuranyl-benzimidazoles, while the same reaction afforded 3-cyano-benzopyrrolo-imidazoles under microwave irradiation. Two nonequivalent nucleophilic centers on benzimidazole moiety were manipulated elegantly by different reaction conditions to achieve the skeletal diversity.

  19. Above-room-temperature ferroelectricity and antiferroelectricity in benzimidazoles

    Science.gov (United States)

    Horiuchi, Sachio; Kagawa, Fumitaka; Hatahara, Kensuke; Kobayashi, Kensuke; Kumai, Reiji; Murakami, Youichi; Tokura, Yoshinori

    2012-12-01

    The imidazole unit is chemically stable and ubiquitous in biological systems; its proton donor and acceptor moieties easily bind molecules into a dipolar chain. Here we demonstrate that chains of these amphoteric molecules can often be bistable in electric polarity and electrically switchable, even in the crystalline state, through proton tautomerization. Polarization-electric field (P-E) hysteresis experiments reveal a high electric polarization ranging from 5 to 10 μC cm-2 at room temperature. Of these molecules, 2-methylbenzimidazole allows ferroelectric switching in two dimensions due to its pseudo-tetragonal crystal symmetry. The ferroelectricity is also thermally robust up to 400 K, as is that of 5,6-dichloro-2-methylbenzimidazole (up to ~373 K). In contrast, three other benzimidazoles exhibit double P-E hysteresis curves characteristic of antiferroelectricity. The diversity of imidazole substituents is likely to stimulate a systematic exploration of various structure-property relationships and domain engineering in the quest for lead- and rare-metal-free ferroelectric devices.

  20. Vibrational dynamics of adsorbed molecules under conditions of photodesorption: Pump-probe SFG spectra of CO/Pt(111)

    Science.gov (United States)

    Fournier, Frédéric; Zheng, Wanquan; Carrez, Serge; Dubost, Henri; Bourguignon, Bernard

    2004-09-01

    Interaction of CO adsorbed on Pt(111) with electrons and phonons is studied experimentally by means of a pump-probe experiment where CO is probed by IR+visible sum frequency generation under a pump laser intensity that allows photodesorption. Vibrational spectra of CO internal stretch are obtained as a function of pump-probe delay. A two-temperature and anharmonic coupling model is used to extract from the spectra the real time variations of CO peak frequency and dephasing time. The main conclusions are the following: (i) The CO stretch is perturbed by two low-frequency modes, assigned to frustrated rotation and frustrated translation. (ii) The frustrated rotation is directly coupled to electrons photoexcited in Pt(111) by the pump laser. (iii) There is no evidence of Pt-CO stretch excitation in the spectra. The implications for the photodesorption dynamics are discussed.

  1. Bioorthogonal cyclization-mediated in situ self-assembly of small-molecule probes for imaging caspase activity in vivo

    Science.gov (United States)

    Ye, Deju; Shuhendler, Adam J.; Cui, Lina; Tong, Ling; Tee, Sui Seng; Tikhomirov, Grigory; Felsher, Dean W.; Rao, Jianghong

    2014-06-01

    Directed self-assembly of small molecules in living systems could enable a myriad of applications in biology and medicine, and already this has been used widely to synthesize supramolecules and nano/microstructures in solution and in living cells. However, controlling the self-assembly of synthetic small molecules in living animals is challenging because of the complex and dynamic in vivo physiological environment. Here we employ an optimized first-order bioorthogonal cyclization reaction to control the self-assembly of a fluorescent small molecule, and demonstrate its in vivo applicability by imaging caspase-3/7 activity in human tumour xenograft mouse models of chemotherapy. The fluorescent nanoparticles assembled in situ were imaged successfully in both apoptotic cells and tumour tissues using three-dimensional structured illumination microscopy. This strategy combines the advantages offered by small molecules with those of nanomaterials and should find widespread use for non-invasive imaging of enzyme activity in vivo.

  2. Simple, mild, and highly efficient synthesis of 2-substituted benzimidazoles and bis-benzimidazoles

    Energy Technology Data Exchange (ETDEWEB)

    Eren, Bilge, E-mail: bilge.eren@bilecik.edu.tr [Faculty of Science and Arts, Department of Chemistry, Bilecik Seyh Edebali University, (Turkey); Bekdemir, Yunus [Faculty of Science and Arts, Canik Basari University, Samsun (Turkey)

    2014-07-01

    A new convenient method for preparation of 2-substituted benzimidazoles and bis-benzimidazoles is presented. In this method, o-phenylenediamines were condensed with bisulfite adducts of various aldehydes and di-aldehydes under neat conditions by microwave heating. The results were also compared with results of synthesis by conventional heating under reflux. Structures of the products were confirmed by infrared, {sup 1}H- and {sup 13}C-NMR spectroscopy. Short reaction times, good yields, easy purification of products, and mild reaction conditions are the main advantages of this method. (author)

  3. Simple, mild, and highly efficient synthesis of 2-substituted benzimidazoles and bis-benzimidazoles

    International Nuclear Information System (INIS)

    Eren, Bilge; Bekdemir, Yunus

    2014-01-01

    A new convenient method for preparation of 2-substituted benzimidazoles and bis-benzimidazoles is presented. In this method, o-phenylenediamines were condensed with bisulfite adducts of various aldehydes and di-aldehydes under neat conditions by microwave heating. The results were also compared with results of synthesis by conventional heating under reflux. Structures of the products were confirmed by infrared, 1 H- and 13 C-NMR spectroscopy. Short reaction times, good yields, easy purification of products, and mild reaction conditions are the main advantages of this method. (author)

  4. Simple, mild, and highly efficient synthesis of 2-substituted benzimidazoles and bis-benzimidazoles

    Directory of Open Access Journals (Sweden)

    Bilge Eren

    2014-01-01

    Full Text Available A new convenient method for preparation of 2-substituted benzimidazoles and bis-benzimidazoles is presented. In this method, o-phenylenediamines were condensed with bisulfite adducts of various aldehydes and di-aldehydes under neat conditions by microwave heating. The results were also compared with results of synthesis by conventional heating under reflux. Structures of the products were confirmed by infrared, ¹H- and 13C-NMR spectroscopy. Short reaction times, good yields, easy purification of products, and mild reaction conditions are the main advantages of this method.

  5. Poly(imide benzimidazole)s for high temperature polymer electrolyte membrane fuel cells

    DEFF Research Database (Denmark)

    Yuan, Sen; Guo, Xiaoxia; Aili, David

    2014-01-01

    A series of poly(imide benzimidazole) random copolymers (PIBIs) was synthesized by condensation polymerization of biphenyl-4,4'-diyldi(oxo)-4,4'-bis(1,8-naphthalenedicarboxylic anhydride) (BPNDA), 2-(4-aminophenyl)-5-aminobenzimidazole (APABI) and 4,4'diaminodiphenyl ether (ODA) in m-cresol in th......A series of poly(imide benzimidazole) random copolymers (PIBIs) was synthesized by condensation polymerization of biphenyl-4,4'-diyldi(oxo)-4,4'-bis(1,8-naphthalenedicarboxylic anhydride) (BPNDA), 2-(4-aminophenyl)-5-aminobenzimidazole (APABI) and 4,4'diaminodiphenyl ether (ODA) in m...

  6. 1-ethyl gallate-2-substituted phenoxymethyl benzimidazoles: synthesis, molecular structure, antimicrobial activities and complex with cr(iii)

    International Nuclear Information System (INIS)

    Zhao, L.; Wu, J.; Wu, J.; Wang, Z.; Gu, H.

    2017-01-01

    The design of gallate and benzimidazole containing derivatives is expected to produce new bioactive molecules with multiple applications. Here the synthesis of eight novel benzimidazole compounds containing ethyl gallate and substituted phenoxymethyl units are reported. Firstly, the ring closure reaction between o-phenylendiamine and substituted phenoxyacetic acids resulted in 2-substituted phenoxymethyl benzimidazoles that were then modified by the N-hydroxyethylation with 2-chloroethyl alcohol under a phase transfer catalysis condition. The obtained 1-hydroxyethyl-2-substituted phenoxymethyl benzimidazoles were finally translated into the target title compounds 8a-h by an indirect esterification method in which three O-H groups of gallic acid were first protected by acetyls and deprotected after the esterification reaction by adding hydrazine hydrate. The structures of the title products 8a-h were fully characterized and confirmed by elemental analysis, MS, IR, 1H-NMR, 13C-NMR and single crystal X-ray diffraction techniques. Antimicrobial tests by inhibition zones indicated that these compounds exhibited diverse inhibitory effects against the test bacteria and fungi, and the type and position of the substituent groups in the phenoxymethyl moieties had obvious influence on their antimicrobial activities. Furthermore, the Cr(III) complex of 8h was synthesized, and various spectral, elemental and thermal analysis results confirmed that the central Cr(III) atom coordinated with adjacent hydroxyl groups of two 8h ligands, nitrate and H2O, respectively. (author)

  7. Synthesis of benzimidazoles via iridium-catalyzed acceptorless dehydrogenative coupling.

    Science.gov (United States)

    Sun, Xiang; Lv, Xiao-Hui; Ye, Lin-Miao; Hu, Yu; Chen, Yan-Yan; Zhang, Xue-Jing; Yan, Ming

    2015-07-21

    Iridium-catalyzed acceptorless dehydrogenative coupling of tertiary amines and arylamines has been developed. A number of benzimidazoles were prepared in good yields. An iridium-mediated C-H activation mechanism is suggested. This finding represents a novel strategy for the synthesis of benzimidazoles.

  8. Preferential adsorption of NH3 gas molecules on MWCNT defect sites probed using in situ Raman spectroscopy

    CSIR Research Space (South Africa)

    Chimowa, George

    2017-06-01

    Full Text Available The preferential adsorption of NH(sub3) gas molecules on multi-walled carbon nanotubes (MWCNTs) was studied using in situ Raman spectroscopy. It was observed that the full widths at half maximum of the G band and the intensity ratio I(sub2D...

  9. 5-[(E-(2-Hydroxybenzylideneamino]-1H-1,3-benzimidazole-2(3H-thione

    Directory of Open Access Journals (Sweden)

    Hoong-Kun Fun

    2011-01-01

    Full Text Available There are two molecules in the asymmetric unit of the title compound, C14H11N3OS. In each, the benzimidazole ring system is essentially planar, with maximum deviations of 0.010 (2 and 0.006 (2 Å, and makes dihedral angles of 8.70 (9 and 13.75 (8°, respectively, with the hydroxy-substituted benzene rings. Each molecule adopts an E configuration about the central C=N double bond. In the crystal, the two independent molecules are connected via intermolecular N—H...S hydrogen bonds, forming dimers. Furthermore, the dimers are connected by N—H...O hydrogen bonds into molecular ribbons along the c axis. There is an intramolecular O—H...N hydrogen bond in each molecule, which generates an S(6 ring motif.

  10. Iminodiacetic acid derivatives of benzimidazole. Synthesis of N-(benzimidazol-2-ylmethyl)iminodiacetic acids

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, F C; Wilson, J G [Australian Atomic Energy Commission Research Establishment, Lucas Heights. Isotope Div.

    1983-01-01

    Ten new N-(2-benzimidazolylmethyl)iminodiacetic acids (BIMIDA) have been synthesized from the corresponding o-phenylenediamines via intermediate 2-chloromethyl and 2-aminomethyl benzimidazoles as ligands for Tc-99m. Anomalies associated with the synthesis of the iodo-substituted compound are described.

  11. An efficient one-pot two catalyst system in the construction of 2-substituted benzimidazoles: synthesis of benzimidazo[1,2-c]quinazolines.

    Science.gov (United States)

    Cimarelli, Cristina; Di Nicola, Matteo; Diomedi, Simone; Giovannini, Riccardo; Hamprecht, Dieter; Properzi, Roberta; Sorana, Federico; Marcantoni, Enrico

    2015-12-28

    The benzimidazole core is a common moiety in a large number of natural products and pharmacologically active small molecules. The synthesis of novel benzimidazole derivatives remains a main focus in medicinal research. In continuation of the efforts towards Ce(III) catalysts for organic transformations, we observed for the first time the activity of the iodide ion and copper cation in activating CeCl3·7H2O in the selective formation of prototypical 2-substituted benzimidazoles. The one-pot CeCl3·7H2O-CuI catalytic system procedure includes the cyclo-dehydrogenation of aniline Schiff's bases, generated in situ from the condensation of 1,2-phenylenediamine and aldehydes, followed by the oxidation with iodine, which works as a hydrogen sponge. Mild reaction conditions, good to excellent yields, and clean reactions make the procedure a useful contribution to the synthesis of biologically active fused heterocycles containing benzimidazoquinazolines.

  12. Defining the RNA Internal Loops Preferred by Benzimidazole Derivatives via Two-Dimensional Combinatorial Screening and Computational Analysis

    Science.gov (United States)

    Velagapudi, Sai Pradeep; Seedhouse, Steven J.; French, Jonathan

    2011-01-01

    RNA is an important therapeutic target, however, RNA targets are generally underexploited due to a lack of understanding of the small molecules that bind RNA and the RNA motifs that bind small molecules. Herein, we describe the identification of the RNA internal loops derived from a 4096-member 3×3 nucleotide loop library that are the most specific and highest affinity binders to a series of four designer, drug-like benzimidazoles. These studies establish a potentially general protocol to define the highest affinity and most specific RNA motif targets for heterocyclic small molecules. Such information could be used to target functionally important RNAs in genomic sequence. PMID:21604752

  13. Predicting Organic Cation Sorption Coefficients: Accounting for Competition from Sorbed Inorganic Cations Using a Simple Probe Molecule.

    Science.gov (United States)

    Jolin, William C; Goyetche, Reaha; Carter, Katherine; Medina, John; Vasudevan, Dharni; MacKay, Allison A

    2017-06-06

    With the increasing number of emerging contaminants that are cationic at environmentally relevant pH values, there is a need for robust predictive models of organic cation sorption coefficients (K d ). Current predictive models fail to account for the differences in the identity, abundance, and affinity of surface-associated inorganic exchange ions naturally present at negatively charged receptor sites on environmental solids. To better understand how organic cation sorption is influenced by surface-associated inorganic exchange ions, sorption coefficients of 10 organic cations (including eight pharmaceuticals and two simple probe organic amines) were determined for six homoionic forms of the aluminosilicate mineral, montmorillonite. Organic cation sorption coefficients exhibited consistent trends for all compounds across the various homoionic clays with sorption coefficients (K d ) decreasing as follows: K d Na + > K d NH 4 + ≥ K d K + > K d Ca 2+ ≥ K d Mg 2+ > K d Al 3+ . This trend for competition between organic cations and exchangeable inorganic cations is consistent with the inorganic cation selectivity sequence, determined for exchange between inorganic ions. Such consistent trends in competition between organic and inorganic cations suggested that a simple probe cation, such as phenyltrimethylammonium or benzylamine, could capture soil-to-soil variations in native inorganic cation identity and abundance for the prediction of organic cation sorption to soils and soil minerals. Indeed, sorption of two pharmaceutical compounds to 30 soils was better described by phenyltrimethylammonium sorption than by measures of benzylamine sorption, effective cation exchange capacity alone, or a model from the literature (Droge, S., and Goss, K. Environ. Sci. Technol. 2013, 47, 14224). A hybrid approach integrating structural scaling factors derived from this literature model of organic cation sorption, along with phenyltrimethylammonium K d values, allowed for

  14. Adsorption of a cationic dye molecule on polystyrene microspheres in colloids: effect of surface charge and composition probed by second harmonic generation.

    Science.gov (United States)

    Eckenrode, Heather M; Jen, Shih-Hui; Han, Jun; Yeh, An-Gong; Dai, Hai-Lung

    2005-03-17

    Nonlinear optical probe, second harmonic generation (SHG), of the adsorption of the dye molecule malachite green (MG), in cationic form at pH polystyrene microspheres in aqueous solution is used to study the effect of surface charge and composition on molecular adsorption. Three types of polystyrene microspheres with different surface composition are investigated: (1) a sulfate terminated, anionic surface, (2) a neutral surface without any functional group termination, and (3) an amine terminated, cationic surface. The cationic dye was found to adsorb at all three surfaces, regardless of surface charge. The adsorption free energies, DeltaG's, measured for the three surfaces are -12.67, -12.39, and -10.46 kcal/mol, respectively, with the trend as expected from the charge interactions. The adsorption density on the anionic surface, where attractive charge-charge interaction dominates, is determined by the surface negative charge density. The adsorption densities on the neutral and cationic surfaces are on the other hand higher, perhaps as a result of a balance between minimizing repulsive charge interaction and maximizing attractive molecule-substrate and intermolecular interactions. The relative strength of the SH intensity per molecule, in combination of a model calculation, reveals that the C(2) axis of the MG molecule is nearly perpendicular to the surface on the anionic surface and tilts away from the surface norm when the surface is neutral and further away when cationic. Changing the pH of the solution may alter the surface charge and subsequently affect the adsorption configuration and SH intensity.

  15. Look fast: Crystallization of conjugated molecules during solution shearing probed in-situ and in real time by X-ray scattering

    KAUST Repository

    Smilgies, Detlef Matthias; Li, Ruipeng; Giri, Gaurav; Chou, Kang Wei; Diao, Ying; Bao, Zhenan; Amassian, Aram

    2012-01-01

    High-speed solution shearing, in which a drop of dissolved material is spread by a coating knife onto the substrate, has emerged as a versatile, yet simple coating technique to prepare high-mobility organic thin film transistors. Solution shearing and subsequent drying and crystallization of a thin film of conjugated molecules is probed in situ using microbeam grazing incidence wide-angle X-ray scattering (μGIWAXS). We demonstrate the advantages of this approach to study solution based crystal nucleation and growth, and identify casting parameter combinations to cast highly ordered and laterally aligned molecular thin films. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Look fast: Crystallization of conjugated molecules during solution shearing probed in-situ and in real time by X-ray scattering

    KAUST Repository

    Smilgies, Detlef Matthias

    2012-12-20

    High-speed solution shearing, in which a drop of dissolved material is spread by a coating knife onto the substrate, has emerged as a versatile, yet simple coating technique to prepare high-mobility organic thin film transistors. Solution shearing and subsequent drying and crystallization of a thin film of conjugated molecules is probed in situ using microbeam grazing incidence wide-angle X-ray scattering (μGIWAXS). We demonstrate the advantages of this approach to study solution based crystal nucleation and growth, and identify casting parameter combinations to cast highly ordered and laterally aligned molecular thin films. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Local 3d Electronic Structures of Co-Based Complexes with Medicinal Molecules Probed by Soft X-ray Absorption

    Science.gov (United States)

    Yamagami, Kohei; Fujiwara, Hidenori; Imada, Shin; Kadono, Toshiharu; Yamanaka, Keisuke; Muro, Takayuki; Tanaka, Arata; Itai, Takuma; Yoshinari, Nobuto; Konno, Takumi; Sekiyama, Akira

    2017-07-01

    We have examined the local 3d electronic structures of Co-Au multinuclear complexes with the medicinal molecules d-penicillaminate (d-pen) [Co{Au(PPh3)(d-pen)}2]ClO4 and [Co3{Au3(tdme)(d-pen)3}2] by Co L2,3-edge soft X-ray absorption (XAS) spectroscopy, where PPh3 denotes triphenylphosphine and tdme stands for 1,1,1-tris[(diphenylphosphino)methyl]ethane. The Co L2,3-edge XAS spectra indicate the localized ionic 3d electronic states in both materials. The experimental spectra are well explained by spectral simulation for a localized Co ion under ligand fields with the full multiplet theory, which verifies that the ions are in the low-spin Co3+ state in the former compound and in the high-spin Co2+ state in the latter.

  18. First hyperpolarizability in a new benzimidazole derivative

    International Nuclear Information System (INIS)

    Rodembusch, Fabiano Severo; Buckup, Tiago; Segala, Maximiliano; Tavares, Luciana; Correia, Ricardo Rego Bordalo; Stefani, Valter

    2004-01-01

    A new benzimidazole, 2-(4'-amino-2'-hydroxyphenyl)-6-nitrobenzimidazole (LEN), with promising applications in nonlinear optics were synthesized, purified and characterized by classical techniques. The UV-Vis and steady-state fluorescence of LEN in solution were applied in order to characterize the photophysical behaviour of this new fluorescent dye. The Hyper-Rayleigh Scattering study indicates a remarkable increase in the β absolute value (1197.3 ± 1.2 x 10 -30 esu) of the LEN in acetone at 1064 nm, when comparing with a previously described benzoxazole (BO6). The ratio between the experimental β and the maximum theoretical value using a two-level model was also improved by a factor 6. Ab initio and semi-empirical calculations of the dipole moments and the first hyperpolarizability are also presented. The enhancement in the experimental hyperpolarizability value in relation to BO6 is explained in terms of the benzimidazolic ring basicity and a prototropic effect (annular tautomerism) present in the LEN, identified as a resonance-assisted hydrogen bond, which leads to a stronger electronic delocalization

  19. Eu(III)-functionalized MIL-124 as fluorescent probe for highly selectively sensing ions and organic small molecules especially for Fe(III) and Fe(II).

    Science.gov (United States)

    Xu, Xiao-Yu; Yan, Bing

    2015-01-14

    A layerlike MOF (MIL-124, orGa2(OH)4(C9O6H4)) has been prepared and chosen as a parent compound to encapsulate Eu(3+) cations by one uncoordinated carbonyl group in its pores. The Eu(3+)-incorporated sample (Eu(3+)@MIL-124) is fully characterized, which shows excellent luminescence and good fluorescence stability in water or other organic solvents. Subsequently, we choose Eu(3+)@MIL-124 as sensitive probe for sensing metal ions, anions, and organic small molecules because of its robust framework. Studying of the luminescence properties reveals that the complex Eu(3+)@MIL-124 was developed as a highly selective and sensitive probe for detection of Fe(3+) (detection limit, 0.28 μM) and Fe(2+) ions through fluorescence quenching of Eu(3+) and MOF over other metal ions. In connection to this, a probable sensing mechanism was also discussed in this paper. In addition, when Eu(3+)@MIL-124 was immersed in the different anions solutions and organic solvents, it also shows highly selective for Cr2O7(2-)(detection limit, 0.15 μM)and acetone. Remarkably, it is the first Eu-doped MOF to exhibit an excellent ability for the detection of Fe(3+) and Fe(2+) in an aqueous environment without any structural disintegration of the framework.

  20. The discussion of descriptors for the QSAR model and molecular dynamics simulation of benzimidazole derivatives as corrosion inhibitors

    International Nuclear Information System (INIS)

    Li, Lu; Zhang, Xiuhui; Gong, Shida; Zhao, Hongxia; Bai, Yang; Li, Qianshu; Ji, Lin

    2015-01-01

    Graphical abstract: - Highlights: • Aromaticity is used as a descriptor in QSAR model to describe corrosion inhibition. • Improved calculation of I and A is correlated well with inhibition efficiencies. • Binding energies were calculated using a realistic corrosion environment. • Nonlinear QSAR model was built by support vector machine with radial basis function. • Six designed benzimidazole molecules are predicted with high inhibition efficiencies. - Abstract: The corrosion inhibition performances of 20 protonated benzimidazole derivatives were studied using theoretical methods. Nuclear Independent Chemical Shift (NICS), the measurement of aromaticity, demonstrated good correlation with inhibition efficiencies and was used as a descriptor. Binding energies were calculated on the basis of molecular dynamics simulations using a realistic corrosive environment. Some improved descriptors correlate well with experimental inhibition efficiencies. A reliable nonlinear quantitative structure–activity relationship model was constructed by a support vector machine approach. The correlation coefficient and root-mean-square error were 0.96 and 6.79%, respectively. Additionally, six new benzimidazole molecules were designed, and their inhibition efficiencies were predicted.

  1. Synthesis and characterisation of ruthenium(III) complexes with benzimidazole derivatives

    International Nuclear Information System (INIS)

    Vyas, P.C.; Kaur, N.; Goel, A.K.; Vyas, S.

    1995-01-01

    Complexes of ruthenium trichloride with biologically important benzimidazole derivatives, viz., 2-(hydroxy methyl) benzimidazole, 2-(l-hydroxy ethyl) benzimidazole, 2-(mercapto methyl) benzimidazole, 2-(l-mercapto ethyl) benzimidazole, and 2,2'-bis-benzimidazole have been synthesized by reacting the above metal chloride and ligands respectively in 1:3 molar ratio. These complexes are characterised on the basis of elemental analysis, molar conductance data, room temperature, magnetic moment values, electronic spectral and IR spectral studies. (author). 17 refs., 2 tabs

  2. Probing the rate-determining region of the potential energy surface for a prototypical ion-molecule reaction.

    Science.gov (United States)

    Xie, Changjian; Liu, Xinguo; Sweeny, Brendan C; Miller, Thomas M; Ard, Shaun G; Shuman, Nicholas S; Viggiano, Albert A; Guo, Hua

    2018-03-13

    We report a joint experimental-theoretical study of the F -  + HCl → HF + Cl - reaction kinetics. The experimental measurement of the rate coefficient at several temperatures was made using the selected ion flow tube method. Theoretical rate coefficients are calculated using the quasi-classical trajectory method on a newly developed global potential energy surface, obtained by fitting a large number of high-level ab initio points with augmentation of long-range electrostatic terms. In addition to good agreement between experiment and theory, analyses suggest that the ion-molecule reaction rate is significantly affected by shorter-range interactions, in addition to the traditionally recognized ion-dipole and ion-induced dipole terms. Furthermore, the statistical nature of the reaction is assessed by comparing the measured and calculated HF product vibrational state distributions to that predicted by the phase space theory.This article is part of the theme issue 'Modern theoretical chemistry'. © 2018 The Author(s).

  3. Infrared absorption by molecular gases as a probe of nanoporous silica xerogel and molecule-surface collisions: Low-pressure results

    Science.gov (United States)

    Vander Auwera, J.; Ngo, N. H.; El Hamzaoui, H.; Capoen, B.; Bouazaoui, M.; Ausset, P.; Boulet, C.; Hartmann, J.-M.

    2013-10-01

    Transmission spectra of gases confined (but not adsorbed) within the pores of a 1.4-cm-thick silica xerogel sample have been recorded between 2.5 and 5 μm using a high-resolution Fourier transform spectrometer. This was done for pure CO, CO2, N2O, H2O, and CH4 at room temperature and pressures of a few hectopascals. Least-squares fits of measured absorption lines provide the optical-path lengths within the confined (LC) and free (LF) gas inside the absorption cell and the half width at half maximum ΓC of the lines of the confined gases. The values of LC and LF retrieved using numerous transitions of all studied species are very consistent. Furthermore, LC is in satisfactory agreement with values obtained from independent measurements, thus showing that reliable information on the open porosity volume can be retrieved from an optical experiment. The values of ΓC, here resulting from collisions of the molecules with the inner surfaces of the xerogel pores, are practically independent of the line for each gas and inversely proportional to the square root of the probed-molecule molar mass. This is a strong indication that, for the studied transitions, a single collision of a molecule with a pore surface is sufficient to change its rotational state. A previously proposed simple model, used for the prediction of the line shape, leads to satisfactory agreement with the observations. It also enables a determination of the average pore size, bringing information complementary to that obtained from nitrogen adsorption porosimetry.

  4. QSAR Analysis of 2-Amino or 2-Methyl-1-Substituted Benzimidazoles Against Pseudomonas aeruginosa

    Science.gov (United States)

    Podunavac-Kuzmanović, Sanja O.; Cvetković, Dragoljub D.; Barna, Dijana J.

    2009-01-01

    A set of benzimidazole derivatives were tested for their inhibitory activities against the Gram-negative bacterium Pseudomonas aeruginosa and minimum inhibitory concentrations were determined for all the compounds. Quantitative structure activity relationship (QSAR) analysis was applied to fourteen of the abovementioned derivatives using a combination of various physicochemical, steric, electronic, and structural molecular descriptors. A multiple linear regression (MLR) procedure was used to model the relationships between molecular descriptors and the antibacterial activity of the benzimidazole derivatives. The stepwise regression method was used to derive the most significant models as a calibration model for predicting the inhibitory activity of this class of molecules. The best QSAR models were further validated by a leave one out technique as well as by the calculation of statistical parameters for the established theoretical models. To confirm the predictive power of the models, an external set of molecules was used. High agreement between experimental and predicted inhibitory values, obtained in the validation procedure, indicated the good quality of the derived QSAR models. PMID:19468332

  5. Dioxouranium(VI) complexes with benzimidazole and benzoxazole derivatives

    International Nuclear Information System (INIS)

    Mansingh, P.S.; Dash, K.C.

    1995-01-01

    UO 2 LηX 2 [X = NO 3 ,NCS and 0.5 SO 4 and when n = 2, L = 2-(2-hydroxyphyenyl) benzimidazole (HPBI) or 2-(2-aminophenyl) benzimidazole(APBI) and for n=1, L = 2-(2-pyridyl) benzoxazole (PBO)] were synthesized and characterized by several physico chemical techniques including molar conductance data, IR, 1 H and 13 C NMR and thermogravimetric analysis. (author). 5 refs

  6. Boric Acid Catalyzed Convenient Synthesis of Benzimidazoles in Aqueous Media

    OpenAIRE

    Poor Heravi, Mohammad Reza; Ashori, Marjan

    2013-01-01

    Synthesis of benzimidazoles has been developed by the o-phenylenediamine with aldehydes using boric acid an efficient catalyst under mild reaction conditions in aqueous media. The product is applicable to aryl and heteroaryl aldehydes. This reaction led to the formation of benzimidazoles new derivatives in good yields. The FT-IR, 19F-NMR, 1H-NMR, 13C-NMR spectra and elemental analysis confirm the structure of compounds.

  7. Boric Acid Catalyzed Convenient Synthesis of Benzimidazoles in Aqueous Media

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Poor Heravi

    2013-01-01

    Full Text Available Synthesis of benzimidazoles has been developed by the o-phenylenediamine with aldehydes using boric acid an efficient catalyst under mild reaction conditions in aqueous media. The product is applicable to aryl and heteroaryl aldehydes. This reaction led to the formation of benzimidazoles new derivatives in good yields. The FT-IR, 19F-NMR, 1H-NMR, 13C-NMR spectra and elemental analysis confirm the structure of compounds.

  8. Radiation-induced conductivity of polynaphthoyl benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Tiutnev, A P; Berlin, A M; Saenko, V S; Rusanov, A L; Korshak, V V

    1985-01-01

    The nonstationary radiation-induced conductivity of polynaphthoyl benzimidazole, synthesized by single-stage high-temperature catalytic polycondensation, is investigated experimentally. It is shown that the radiation-induced conductivity of this material is characterized by an anomalous (non-Gaussian) transfer of excess charge carriers. The activation energy of the delayed component (0.1 ms after pulse termination) is determined to be 0.12 eV; the volt-ampere characteristic of this component is nonlinear, with the coefficient of nonlinearity increasing with the intensity of the external electric field. Experimental results are interpreted on the basis of the phenomenological theory of jump conductivity proposed by Zviagin. 15 references.

  9. Probing Interactions of N-Donor Molecules with Open Metal Sites within Paramagnetic Cr-MIL-101: A Solid-State NMR Spectroscopic and Density Functional Theory Study.

    Science.gov (United States)

    Wittmann, Thomas; Mondal, Arobendo; Tschense, Carsten B L; Wittmann, Johannes J; Klimm, Ottokar; Siegel, Renée; Corzilius, Björn; Weber, Birgit; Kaupp, Martin; Senker, Juergen

    2018-02-14

    Understanding host-guest interactions is one of the key requirements for adjusting properties in metal-organic frameworks (MOFs). In particular, systems with coordinatively unsaturated Lewis acidic metal sites feature highly selective adsorption processes. This is attributed to strong interactions with Lewis basic guest molecules. Here we show that a combination of 13 C MAS NMR spectroscopy with state-of-the-art density functional theory (DFT) calculations allows one to unravel the interactions of water, 2-aminopyridine, 3-aminopyridine, and diethylamine with the open metal sites in Cr-MIL-101. The 13 C MAS NMR spectra, obtained with ultrafast magic-angle spinning, are well resolved, with resonances distributed over 1000 ppm. They present a clear signature for each guest at the open metal sites. Based on competition experiments this leads to the following binding preference: water open metal sites, the NMR data offer additional information about the guest and framework dynamics. We expect that our strategy has the potential for probing the binding situation of adsorbate mixtures at the open metal sites of MOFs in general and thus accesses the microscopic interaction mechanisms for this important material class, which is essential for deriving structure-property relationships.

  10. 3,4-Dimethoxyphenyl bis-benzimidazole, a novel DNA topoisomerase inhibitor that preferentially targets Escherichia coli topoisomerase I

    Science.gov (United States)

    Bansal, Sandhya; Sinha, Devapriya; Singh, Manish; Cheng, Bokun; Tse-Dinh, Yuk-Ching; Tandon, Vibha

    2012-01-01

    Objectives Antibiotic resistance in bacterial pathogens is a serious clinical problem. Novel targets are needed to combat increasing drug resistance in Escherichia coli. Our objective is to demonstrate that 2-(3,4-dimethoxyphenyl)-5-[5-(4-methylpiperazin-1-yl)-1H-benzimidazol-2yl]-1H-benzimidazole (DMA) inhibits E. coli DNA topoisomerase I more strongly than human topoisomerase I. In addition, DMA is non-toxic to mammalian cells at antibiotic dosage level. Methods In the present study, we have established DMA as an antibacterial compound by determining MICs, post-antibiotic effects (PAEs) and MBCs for different standard as well as clinical strains of E. coli. We have described the differential catalytic inhibitory mechanism of bis-benzimidazole, DMA, for human and E. coli topoisomerase I and topoisomerase II by performing different assays, including relaxation assays, cleavage–religation assays, DNA unwinding assays, ethidium bromide displacement assays, decatenation assays and DNA gyrase supercoiling assays. Results DMA significantly inhibited bacterial growth at a very low concentration, but did not affect human cell viability at higher concentrations. Activity assays showed that it preferentially targeted E. coli topoisomerase I over human topoisomerase I, topoisomerase II and gyrase. Cleavage–religation assays confirmed DMA as a poison inhibitor of E. coli topoisomerase I. This study illuminates new properties of DMA, which may be further modified to develop an efficient topoisomerase inhibitor that is selective towards bacterial topoisomerase I. Conclusions This is the first report of a bis-benzimidazole acting as an E. coli topoisomerase I inhibitor. DMA is a safe, non-cytotoxic molecule to human cells at concentrations that are needed for antibacterial activity. PMID:22945915

  11. Discovery of genomic intervals that underlie nematode responses to benzimidazoles.

    Science.gov (United States)

    Zamanian, Mostafa; Cook, Daniel E; Zdraljevic, Stefan; Brady, Shannon C; Lee, Daehan; Lee, Junho; Andersen, Erik C

    2018-03-01

    Parasitic nematodes impose a debilitating health and economic burden across much of the world. Nematode resistance to anthelmintic drugs threatens parasite control efforts in both human and veterinary medicine. Despite this threat, the genetic landscape of potential resistance mechanisms to these critical drugs remains largely unexplored. Here, we exploit natural variation in the model nematodes Caenorhabditis elegans and Caenorhabditis briggsae to discover quantitative trait loci (QTL) that control sensitivity to benzimidazoles widely used in human and animal medicine. High-throughput phenotyping of albendazole, fenbendazole, mebendazole, and thiabendazole responses in panels of recombinant lines led to the discovery of over 15 QTL in C. elegans and four QTL in C. briggsae associated with divergent responses to these anthelmintics. Many of these QTL are conserved across benzimidazole derivatives, but others show drug and dose specificity. We used near-isogenic lines to recapitulate and narrow the C. elegans albendazole QTL of largest effect and identified candidate variants correlated with the resistance phenotype. These QTL do not overlap with known benzimidazole target resistance genes from parasitic nematodes and present specific new leads for the discovery of novel mechanisms of nematode benzimidazole resistance. Analyses of orthologous genes reveal conservation of candidate benzimidazole resistance genes in medically important parasitic nematodes. These data provide a basis for extending these approaches to other anthelmintic drug classes and a pathway towards validating new markers for anthelmintic resistance that can be deployed to improve parasite disease control.

  12. Evaluation of the Membrane Permeability (PAMPA and Skin) of Benzimidazoles with Potential Cannabinoid Activity and their Relation with the Biopharmaceutics Classification System (BCS)

    OpenAIRE

    Alvarez-Figueroa, M. Javiera; Pessoa-Mahana, C. David; Palavecino-González, M. Elisa; Mella-Raipán, Jaime; Espinosa-Bustos, Cristián; Lagos-Muñoz, Manuel E.

    2011-01-01

    The permeability of five benzimidazole derivates with potential cannabinoid activity was determined in two models of membranes, parallel artificial membrane permeability assay (PAMPA) and skin, in order to study the relationship of the physicochemical properties of the molecules and characteristics of the membranes with the permeability defined by the Biopharmaceutics Classification System. It was established that the PAMPA intestinal absorption method is a good predictor for classifying thes...

  13. [Benzimidazole and its derivatives--from fungicides to designer drugs. A new occupational and environmental hazards].

    Science.gov (United States)

    Lutz, Piotr

    2012-01-01

    Benzimidazole and benzimidazole derivatives play an important role in controlling various fungal pathogens. The benzimidazoles are also used to treat nematode and trematode infections in humans and animals. It acts by binding to the microtubules and stopping hyphal growth. It also binds to the spindle microtubules and blocks nuclear division. The most popular fungicide is carbendazim. The fungicide is used to control plant diseases in cereals and fruits. Laboratory studies have shown that carbendazim cause infertility and destroy the testicles of laboratory animals. Other benzimidazole derivatives are used as a preservative in paint, textile, papermaking, leather industry, and warehousing practices, as well as a preservative of fruits. Occupational exposure to benzimidazole may occur through inhalation and dermal contact with those compounds at workplaces where benzimidazole is used or produced. Some of the benzimidazoles are common environmental pollutants. They are often found in food and fruit products. Some of the benzimidazoles, like a astemizole or esomeprazole have found applications in diverse therapeutical areas. Despite of the clear advantages afforded by the use of benzimidazole derivatives, they share a danger potential. The most hazardous, however, are new illegally synthesed psychoactive drugs known as designer drugs. Some of them, like nitazene, etonitazene or clonitazene belong to benzimidazole derivatives. Laboratory animal studies revealed that etonitazene produced very similar effects in central nervous system as those observed after morphine administration. Considering etonitazene's properties, it seems reasonable to expected that long-term exposure to other benzimidazole derivatives may result in drug abuse and development of drug dependence.

  14. Potential radiosensitizing agents. 5. 2-Substituted benzimidazole derivatives

    International Nuclear Information System (INIS)

    Gupta, R.P.; Larroquette, C.A.; Agrawal, K.C.

    1982-01-01

    A series of 2-substituted benzimidazoles and their derivatives have been synthesized and tested for their ability to selectively sensitize hypoxic Chinese hamster cells (V-79) toward the lethal effect of ionizing radiation. These compounds were prepared by reacting the 2-substituted benzimidazoles with 1,2-epoxy-3-methoxypropane in the presence of potassium carbonate. Reaction of the 2-nitro and 2-methylfonyl analogue with the epoxide also yielded a cyclized material, which was confirmed to be a benzimidazo[2,1-b]oxazole. In an attempt to increase the electron affinity, 5- or 6-nitro-2-substituted-benzimidazoles were also synthesized and then reacted with the epoxide to yield the corresponding 1-substituted derivatives. The results of the biological tests for the radiosensitizing activity of these agents against Chinese hamster cells (V-79) in culture indicated that the 2-nitro-substituted analogues were the most effective sensitizers in this series

  15. Synthesis and biological evaluation of 2-substituted benzimidazole derivatives

    Directory of Open Access Journals (Sweden)

    Gurusamy Mariappan

    2015-09-01

    Full Text Available A novel series of 2-substituted benzimidazole derivatives (3a–3j were synthesized by the reaction of 2-chloro methyl benzimidazole with substituted primary aromatic amines. All the compounds were characterized by UV, IR, 1H NMR, mass spectral data and CHN elemental analysis. The synthesized derivatives were screened for analgesic and anti-inflammatory activities. All the compounds showed significant effect at 100 mg/kg p.o. and the experimental data are statistically significant at p < 0.01 level.

  16. Coordination compounds of metals with imidazoles and benzimidazoles

    International Nuclear Information System (INIS)

    Novikova, G.A.; Molodkin, A.K.; Kukalenko, S.S.

    1988-01-01

    Methods of preparation, composition and structure of UO 2 2+ , Th 4+ , Mo 3+ , Cd 2+ , Ln 3+ metal ion complexes with imidazoles and benzimidazoles are considered in reviews of native and foreign literature of up to 1985. Complexes are customarily prepared by direct interaction of ligands with inorganic salts in different organic solvents. Complex composition is defined by the nature of complexing metal and inorganic salt anion, ligand volume and basicity, as well as solvent characteristics. Effect of R substituent in imidazole and benzimidazole side chain on composition of coordination compounds is considered

  17. Benzimidazole grafted polybenzimidazoles for proton exchange membrane fuel cells

    DEFF Research Database (Denmark)

    Yang, Jingshuai; Aili, David; Li, Qingfeng

    2013-01-01

    High molecular weight polybenzimidazole (PBI) was synthesized and grafted with benzimidazole pendant groups. The high molecular weight of PBI resulted in good film-forming properties and superior tensile strength. With a phosphoric acid doping level (ADL) of 13.1, a tensile strength of 16 MPa...... was achieved at room temperature. Grafting of benzimidazole moieties onto the PBI macromolecular chain introduced additional basic sites which allowed the membrane to achieve higher phosphoric acid uptakes. A molar acid conductivity, defined as the specific conductivity of each mole of doping acid...

  18. Rhenium(V) complexing with benzimidazole in acidic media

    International Nuclear Information System (INIS)

    Zakaeva, R.Sh.; Gagieva, S.Ch.; Kaloev, N.I.; Bukov, N.N.; Panyushkin, V.T.

    2003-01-01

    Coordination compounds of rhenium(V) with 1H-benzimidazole (L) separated from acid media: (HL) 2 [ReOX 5 ](H 2 O) n and [ReOL x X y (H 2 O) z ](H 2 O) n (HL and L - protonated and deprotonated forms of benzimidazole; X = Cl - , Br - ) were studied by the methods of IR spectroscopy, 1 H NMR spectroscopy and thermal gravimetric analysis. Methods of ligand coordination in the complexes are discussed on the basis of data obtained [ru

  19. The 2D Selfassembly of Benzimidazole and its Co-crystallization

    Science.gov (United States)

    Costa, Paulo; Teeter, Jacob; Kunkel, Donna; Sinitskii, Alexander; Enders, Axel

    Benzimidazoles (BI) are organic molecules that form ferroelectric crystals. Key to their ferroelectric behavior are the switchable N . . . HN type bonds and how they couple to the electron system of the molecules. We attempted to crystallize BI on various metal surfaces and studied them using STM. We observed that on Au and Ag, BI joins into zipper chains characteristic of its bulk structure that can pack into a continuous 2D layer. Because the dipole of BI lies in the direction of its switchable hydrogen bond, these zippers should in principle have reversible polarizations that point along the direction they run. BI's crystallization is reminiscent to how croconic acid (CA) crystallizes in 2D using O . . . HO bonding, suggesting that these molecules may be able to co-crystallize through OH . . . N bonds. This would present the opportunity to modify BI's properties, such as the energy needed to switch a hydrogen from a donor to acceptor site. When co-deposited, CA and BI successfully combine into a co-crystal formed by building blocks consisting of 2 CA and 2 BI molecules. These findings demonstrate the usefulness of using STM as a preliminary check to verify if two molecules are compatible with each other without having to attempt crystallization with multiple solvents and mixing methods.

  20. Benzimidazole condensed ring systems 10 (1). Synthesis and cytotoxic activity of some pyrido[1,2-a]benzimidazoles.

    Science.gov (United States)

    Badawey, E S; Kappe, T

    1995-01-01

    As a part of research project on the synthesis of a number of pyrido[1,2-a]benzimidazole derivatives with possible antineoplastic activity and as a result of the interesting antineoplastic activity recorded for one such compounds (NSC 649900), some new pyrido[1,2-a]benzimidazoles were prepared and evaluated for such activity. Compound (11, NSC 660334) exhibited a moderate in vitro antineoplastic activity especially against most of the leukemia cell lines, while compound (10, VM30309) showed a good cytotoxic activity against Artina salina larvae (IC50 = 1.75 micrograms/ml).

  1. Structure-activity relationships of benzimidazole-based glutaminyl cyclase inhibitors featuring a heteroaryl scaffold.

    Science.gov (United States)

    Ramsbeck, Daniel; Buchholz, Mirko; Koch, Birgit; Böhme, Livia; Hoffmann, Torsten; Demuth, Hans-Ulrich; Heiser, Ulrich

    2013-09-12

    Glutaminyl cyclase (hQC) has emerged as a new potential target for the treatment of Alzheimer's disease (AD). The inhibition of hQC prevents of the formation of the Aβ3(pE)-40,42 species which were shown to be of elevated neurotoxicity and are likely to act as a seeding core, leading to an accelerated formation of Aβ-oligomers and fibrils. This work presents a new class of inhibitors of hQC, resulting from a pharmacophore-based screen. Hit molecules were identified, containing benzimidazole as the metal binding group connected to 1,3,4-oxadiazole as the central scaffold. The subsequent optimization resulted in benzimidazolyl-1,3,4-thiadiazoles and -1,2,3-triazoles with an inhibitory potency in the nanomolar range. Further investigation into the potential binding mode of the new compound classes combined molecular docking and site directed mutagenesis studies.

  2. Crystal structures of HIV-1 nonnucleoside reverse transcriptase inhibitors: N-benzyl-4-methyl-benzimidazoles

    Science.gov (United States)

    Ziółkowska, Natasza E.; Michejda, Christopher J.; Bujacz, Grzegorz D.

    2009-07-01

    HIV-1 nonnucleoside reverse transcriptase inhibitors are potentially specific and effective drugs in AIDS therapy. The presence of two aromatic systems with an angled orientation in the molecule of the inhibitor is crucial for interactions with HIV-1 RT. The inhibitor drives like a wedge into the cluster of aromatic residues of RT HIV-1 and restrains the enzyme in a conformation that blocks the chemical step of nucleotide incorporation. Structural studies provide useful information for designing new, more active inhibitors. The crystal structures of four NNRTIs are presented here. The investigated compounds are derivatives of N-benzyl-4-methyl-benzimidazole with various aliphatic and aromatic substituents at carbon 2 positions and a 2,6-dihalogeno-substituted N-benzyl moiety. Structural data reported here show that the conformation of the investigated compounds is relatively rigid. Such feature is important for the nonnucleoside inhibitor binding to HIV-1 reverse transcriptase.

  3. Glutathione transferase-mediated benzimidazole-resistance in Fusarium graminearum.

    Science.gov (United States)

    Sevastos, A; Labrou, N E; Flouri, F; Malandrakis, A

    2017-09-01

    Fusarium graminearum laboratory mutants moderately (MR) and highly (HR) benzimidazole-resistant, carrying or not target-site mutations at the β 2 -tubulin gene were utilized in an attempt to elucidate the biochemical mechanism(s) underlying the unique BZM-resistance paradigm of this fungal plant pathogen. Relative expression analysis in the presence or absence of carbendazim (methyl-2-benzimidazole carbamate) using a quantitative Real Time qPCR (RT-qPCR) revealed differences between resistant and the wild-type parental strain although no differences in expression levels of either β 1 - or β 2 -tubulin homologue genes were able to fully account for two of the highly resistant phenotypes. Glutathione transferase (GST)-mediated detoxification was shown to be -at least partly- responsible for the elevated resistance levels of a HR isolate bearing the β 2 -tubulin Phe200Tyr resistance mutation compared with another MR isolate carrying the same mutation. This benzimidazole-resistance mechanism is reported for the first time in F. graminearum. No indications of detoxification involved in benzimidazole resistance were found for the rest of the isolates as revealed by GST and glutathione peroxidase (GPx) activities and bioassays using monoxygenase and hydrolase detoxification enzyme inhibiting synergists. Interestingly, besides the Phe200Tyr mutation-carrying HR isolate, the remaining highly-carbendazim resistant phenotypes could not be associated with any of the target site modification/overproduction, detoxification or reduced uptake-increased efflux mechanisms. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. QSAR study of benzimidazole derivatives inhibition on escherichia ...

    African Journals Online (AJOL)

    The paper describes a quantitative structure-activity relationship (QSAR) study of IC50 values of benzimidazole derivatives on escherichia coli methionine aminopeptidase. The activity of the 32 inhibitors has been estimated by means of multiple linear regression (MLR) and artificial neural network (ANN) techniques.

  5. Uptake of benzimidazoles by Trichuris suis in vivo in pigs

    DEFF Research Database (Denmark)

    Hansen, Tina Vicky Alstrup; Friis, Christian; Nejsum, Peter

    2014-01-01

    It is recognized that the clinical efficacy of single dose benzimidazoles (BZs) against the nematode, Trichuris suis of pigs and the closely related Trichuris trichiura in humans is only poor to moderate. Recent in vitro studies have indicated that a low uptake of fenbendazole (FBZ) in T. suis may...

  6. The Synthesis of Dicationic Extended Bis-Benzimidazoles

    OpenAIRE

    Kang, Zhijan; Dykstra, Christine C.; Boykin, David W.

    2004-01-01

    The synthesis of extended dicationic bis-benzimidazoles starting from trans-1,2-bis(4-cyanophenyl)ethene and trans-1,2-bis(4-cyanophenyl)cyclopropane is reported. The target diamidines show significant in vitro activity against B. subtilis.

  7. Data on the effects of imidazo[1,2-a]benzimidazole and pyrimido[1,2-a]benzimidazole compounds on intraocular pressure of ocular normotensive rats

    Directory of Open Access Journals (Sweden)

    Adrian Julian Marcus

    2018-06-01

    Full Text Available This data is to document the intraocular pressure (IOP lowering activity of imidazo[1,2-a]benzimidazole and pyrimido[1,2-a]benzimidazole compounds in ocular normotensive rats. Effects of single drop application of imidazo[1,2-a]benzimidazole and pyrimido[1,2-a]benzimidazole compounds on IOP in ocular normotensive rats are presented at 3 different concentrations (0.1%, 0.2% and 0.4%. Time course of changes in IOP is presented over 6 h period post-instillation. The IOP lowering activities of test compounds were determined by assessing maximum decrease in IOP from baseline and corresponding control, duration of IOP lowering and area under curve (AUC of time versus response curve. Data shown here may serve as benchmarks for other researchers studying IOP-lowering effect of imidazo[1,2-a]benzimidazole and pyrimido[1,2-a]benzimidazole compounds and would be useful in determining therapeutic potential of these test compounds as IOP lowering agents. Keywords: Drug screening, Intraocular pressure, Intraocular pressure lowering activity, Imidazo[1,2-a]benzimidazoles, Pyrimido[1,2-a]benzimidazoles, Ocular normotensive rats, Rebound tonometry

  8. Design, synthesis and biological evaluation of novel hydroxy-phenyl-1H-benzimidazoles as radical scavengers and UV-protective agents.

    Science.gov (United States)

    Bino, Alessia; Baldisserotto, Anna; Scalambra, Emanuela; Dissette, Valeria; Vedaldi, Daniela Ester; Salvador, Alessia; Durini, Elisa; Manfredini, Stefano; Vertuani, Silvia

    2017-12-01

    An ever-increasing incidence of skin neoplastic diseases is registered. Therefore, it is important to protect the skin from the UV radiation that reaches the epidermis and dermis but also to block ROS generated by them. Our attention was attracted in developing new compounds provided with both UV filtering and antioxidant capacities. To this end, 2-phenyl-1H-benzimidazole-5-sulfonic acid (PBSA), a known UV filter, was selected as lead compound for its lack of antioxidant activity, high water solubility and good safety profile. PBSA was sequentially modified introducing hydroxyls on the phenyl ring and also substituting the functional group in position 5 of the benzimidazole ring. At the end of the synthetic study, a new, very potent class of antioxidants has been obtained. Surprisingly some of the developed molecules, while devoid of significant UV-filtering activity was endowed with potent UV-filtering booster capability if associated with known commercial UVB and UVA filters.

  9. A study of vibrational spectra and investigations of charge transfer and chemical bonding features of 2-chloro benzimidazole based on DFT computations

    Science.gov (United States)

    Muthunatesan, S.; Ragavendran, V.

    2015-01-01

    Benzimidazoles are bicyclic heteroatomic molecules. Polycyclic heteroatomic molecules have extensive coupling of different modes leading to strong coupling of force constants associated with the various chemical bonds of the molecules. To carry out a detailed vibrational spectroscopic analysis of such a bicyclic heteroatomic molecule, FT-IR and FT-Raman spectra of 2-chloro benzimidazole (CBZ) have been recorded in the condensed phase. Density Functional Theory calculations in the B3LYP/6-31G* level have been carried out to determine the optimized geometry and vibrational frequencies. In order to obtain a close agreement between theoretical and observed frequencies and hence to perform a reliable assignment, the theoretical DFT force field was transformed from Cartesian to local symmetry co-ordinates and then scaled empirically using SQM methodology. The SQM treatment resulted in a RMS deviation of 9.4 cm-1. For visual comparison, the observed and calculated spectra are presented on a common wavenumber scale. From the NBO analysis, the electron density (ED) charge transfers in the σ* and π* antibonding orbitals and second order delocalization energies E(2) confirms the occurrence of intramolecular charge transfer (ICT) within the molecule. The calculated Homo and Lumo energies show that charge transfer occurs within the molecule. The results obtained from the vibrational, NBO and HOMO-LUMO analyses have been properly tabulated.

  10. Synthesis and Analgesic Activity of Novel Derivatives of 1,2-Substituted Benzimidazoles

    Directory of Open Access Journals (Sweden)

    Shobhit Srivastava

    2013-01-01

    Full Text Available A series of novel 2-phenylhydrazinomethyl and 2-(2-hydroxyphenyl-benzimidazole derivatives substituted at the N1-position of benzimidazole nucleus were synthesized as well as screened for analgesic activity. Some of these compounds showed promising analgesic activity when compared with the standard drug diclofenac sodium. The incorporation of a phenylhydrazinomethyl nucleus at 2-position of benzimidazole compound gave a biologically active pharmacophore.

  11. Benzimidazole as Novel Therapy for Hormone-Refractory Metastatic Prostate Cancer

    Science.gov (United States)

    2011-05-01

    8 4 INTRODUCTION The focus of this project is to evaluate the anti-tumor effects of benzimidazoles as a...potential anti-metastatic prostate cancer therapy. We identified benzimidazoles , a class of anti-parasitic drug, in a drug screening process for...preferential anti-tumor activity on metastatic prostate cancer cells. We have data indicate that benzimidazoles have potent anti-tumor activities

  12. Quantum-chemical insight into structure-reactivity relationship in 4,5,6,7-tetrahalogeno-1H-benzimidazoles: a combined X-ray, DSC, DFT/QTAIM, Hirshfeld surface-based, and molecular docking approach.

    Science.gov (United States)

    Latosińska, Jolanta Natalia; Latosińska, Magdalena; Maurin, Jan Krzysztof; Orzeszko, Andrzej; Kazimierczuk, Zygmunt

    2014-03-20

    The weak interaction patterns in 4,5,6,7-tetrahalogeno-1H-benzimidazoles, protein kinase CK2 inhibitors, in solid state are studied by the X-ray method and quantum chemistry calculations. The crystal structures of 4,5,6,7-tetrachloro- and 4,5,6,7-tetrabromo-1H-benzimidazole are determined by X-ray diffraction and refined to a final R-factor of 3.07 and 3.03%, respectively, at room temperature. The compound 4,5,6,7-tetrabromo-1H-benzimidazole, which crystallizes in the I41/a space group, is found to be isostructural with previously studied 4,5,6,7-tetraiodo-1H-benzimidazole in contrast to 4,5,6,7-tetrachloro-1H-benzimidazole, which crystallizes as triclinic P1̅ with 4 molecules in elementary unit. For 4,5,6,7-tetrachloro-1H-benzimidazole, differential scanning calorimetry (DSC) revealed a second order glassy phase transition at Tg = 95°/106° (heating/cooling), an indication of frozen disorder. The lack of 3D isostructurality found in all 4,5,6,7-tetrahalogeno-1H-benzimidazoles is elucidated on the basis of the intra- and intermolecular interactions (hydrogen bonding, van der Waals contacts, and C-H···π interactions). The topological Bader's Quantum Theory of Atoms in Molecules (QTAIM) and Spackman's Hirshfeld surface-based approaches reveal equilibration of electrostatic matching and dispersion van der Waals interactions between molecules consistent with the crystal site-symmetry. The weakening of van der Waals forces accompanied by increasing strength of the hydrogen bond (N-H···N) result in a decrease in the crystal site-symmetry and a change in molecular packing in the crystalline state. Crystal packing motifs were investigated with the aid of Hirshfeld surface fingerprint plots. The ordering 4,5,6,7-tetraiodo > 4,5,6,7-tetrabromo > 4,5,6,7-tetrachloro > 4,5,6,7-tetrafluoro reflects not only a decrease in crystal symmetry but also increase in chemical reactivity (electronic activation), which could explain some changes in biological activity of

  13. Continuous-flow liquid microjunction surface sampling probe connected on-line with high-performance liquid chromatography/mass spectrometry for spatially resolved analysis of small molecules and proteins.

    Science.gov (United States)

    Van Berkel, Gary J; Kertesz, Vilmos

    2013-06-30

    A continuous-flow liquid microjunction surface sampling probe extracts soluble material from surfaces for direct ionization and detection by mass spectrometry. Demonstrated here is the on-line coupling of such a probe with high-performance liquid chromatography/mass spectrometry (HPLC/MS) enabling extraction, separation and detection of small molecules and proteins from surfaces in a spatially resolved (~0.5 mm diameter spots) manner. A continuous-flow liquid microjunction surface sampling probe was connected to a six-port, two-position valve for extract collection and injection to an HPLC column. A QTRAP® 5500 hybrid triple quadrupole linear ion trap equipped with a Turbo V™ ion source operated in positive electrospray ionization (ESI) mode was used for all experiments. The system operation was tested with the extraction, separation and detection of propranolol and associated metabolites from drug dosed tissues, caffeine from a coffee bean, cocaine from paper currency, and proteins from dried sheep blood spots on paper. Confirmed in the tissue were the parent drug and two different hydroxypropranolol glucuronides. The mass spectrometric response for these compounds from different locations in the liver showed an increase with increasing extraction time (5, 20 and 40 s). For on-line separation and detection/identification of extracted proteins from dried sheep blood spots, two major protein peaks dominated the chromatogram and could be correlated with the expected masses for the hemoglobin α and β chains. Spatially resolved sampling, separation, and detection of small molecules and proteins from surfaces can be accomplished using a continuous-flow liquid microjunction surface sampling probe coupled on-line with HPLC/MS detection. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

  14. 1-Hydroxyethyl-2-Substituted Phenoxymethyl Benzimidazoles: Synthesis and Crystal Structures

    International Nuclear Information System (INIS)

    Wu, J.; Wang, Z.; Gu, H.; Chen, W.; Zhao, L.; Zhao, C.

    2016-01-01

    Five novel 1-hydroxyethyl-2-substituted phenoxymethyl benzimidazoles c1-c5 were successfully synthesized by a three-step route. Firstly, five substituted phenoxymethyl acids a1-a5 were prepared by the O-carboxymethylation reaction of the starting substituted phenols under microwave irradiation. Then, these compounds reacted with o-phenylendiamine to get the key intermediates 2-substituted phenoxymethyl benzimidazoles b1-b5. At last, the target compounds were synthesized by the N-hydroxyethylation reaction of b1-b5 with 2-chloroethyl alcohol through the solid-liquid phase transfer catalysis method, where tetrabutyl ammonium bromide (TBAB) was used as the catalyst. The structures of the target compounds were well characterized and verified by elemental analysis, MS, IR, 1H NMR, 13C NMR and single crystal X-ray diffraction analysis. (author)

  15. Benzimidazole-Based Antibacterial Agents Against F. tularensis

    Science.gov (United States)

    Kumar, Kunal; Awasthi, Divya; Lee, Seung-Yub; Cummings, Jason E.; Knudson, Susan E.; Slayden, Richard A.; Ojima, Iwao

    2013-01-01

    Francisella tularensis is a highly virulent pathogenic bacterium. In order to identify novel potential antibacterial agents against F. tularensis, libraries of trisubstituted benzimidazoles were screened against F. tularensis LVS strain. In a preliminary screening assay, remarkably, 23 of 2,5,6- and 2,5,7-trisubstituted benzimidazoles showed excellent activity exhibiting greater than 90 % growth inhibition at 1 µg/mL. Among those hits, 21 compounds showed MIC90 values in the range of 0.35–48.6 µg/mL after accurate MIC determination. In ex-vivo efficacy assays, four of these compounds exhibited 2–3 Log reduction in colony forming units (CFU) per mL at concentrations of 10 and 50 µg/mL. PMID:23623254

  16. Vanadium (4) complexing in phase of adsorbent with benzimidazole groups

    Energy Technology Data Exchange (ETDEWEB)

    Shvoeva, O P; Kuchava, G P; Evtikova, G A; Belyaeva, V K; Myasoedova, G V; Marov, I N [AN SSSR, Moscow (USSR). Inst. Geokhimii i Analiticheskoj Khimii

    1989-04-01

    Equilibrium and kinetic characteristics of V{sup 4+} sorption by POLYORGS XI-H adsorbent with benzimidazole groups (BIm) are investigated. Using ESR method it is stated that (VO{sup 2+}):(BIm)1:2 complex, where VO{sup 2+} is combined with nitrogen atoms of two imidazole groups, is formed in adsorbent phase. The highest distribution factor of 4.7x10{sup 3} is attained at pH6.

  17. Vanadium (4) complexing in phase of adsorbent with benzimidazole groups

    International Nuclear Information System (INIS)

    Shvoeva, O.P.; Kuchava, G.P.; Evtikova, G.A.; Belyaeva, V.K.; Myasoedova, G.V.; Marov, I.N.

    1989-01-01

    Equilibrium and kinetic characteristics of V 4+ sorption by POLYORGS XI-H adsorbent with benzimidazole groups (BIm) are investigated. Using ESR method it is stated that [VO 2+ ]:[BIm]1:2 complex, where VO 2+ is combined with nitrogen atoms of two imidazole groups, is formed in adsorbent phase. The highest distribution factor of 4.7x10 3 is attained at pH6

  18. Design, Synthesis and Biological Evaluation of 2-(2-Amino-5(6-nitro-1H-benzimidazol-1-yl-N-arylacetamides as Antiprotozoal Agents

    Directory of Open Access Journals (Sweden)

    Emanuel Hernández-Núñez

    2017-04-01

    Full Text Available Parasitic diseases are a public health problem affecting millions of people worldwide. One of the scaffolds used in several drugs for the treatment of parasitic diseases is the benzimidazole moiety, a heterocyclic aromatic compound. This compound is a crucial pharmacophore group and is considered a privileged structure in medicinal chemistry. In this study, the benzimidazole core served as a model for the synthesis of a series of 2-(2-amino-5(6-nitro-1H-benzimidazol-1-yl-N-arylacetamides 1–8 as benznidazole analogues. The in silico pharmacological results calculated with PASS platform exhibited chemical structures highly similar to known antiprotozoal drugs. Compounds 1–8 when evaluated in silico for acute toxicity by oral dosing, were less toxic than benznidazole. The synthesis of compounds 1–8 were carried out through reaction of 5(6-nitro-1H-benzimidazol-2-amine (12 with 2-chlroactemides 10a–h, in the presence of K2CO3 and acetonitrile as solvent, showing an inseparable mixture of two regioisomers with the -NO2 group in position 5 or 6 with chemical yields of 60 to 94%. The prediction of the NMR spectra of molecule 1 coincided with the experimental chemical displacements of the regioisomers. Comparisons between the NMR prediction and the experimental data revealed that the regioisomer endo-1,6-NO2 predominated in the reaction. The in vitro antiparasitic activity of these compounds on intestinal unicellular parasites (Giardia intestinalis and Entamoeba histolytica and a urogenital tract parasite (Trichomonas vaginalis were tested. Compound 7 showed an IC50 of 3.95 μM and was 7 time more active against G. intestinalis than benznidazole. Compounds 7 and 8 showed 4 times more activity against T. vaginalis compared with benznidazole.

  19. SYNTHESIS, SPECTRAL AND THEORETICAL CHARACTERIZATION OF 5,6-DICHLORO/DIMETHYL-2-(2´,3´/2´,4´/2´,5´/3´,4´/3´,5´-DIMETHOXYPHENYL-1H-BENZIMIDAZOLES

    Directory of Open Access Journals (Sweden)

    Demet Gürbüz

    2016-12-01

    Full Text Available 5,6-Dichloro/dimethyl-2-(2´,3´/2´,4´/2´,5´/3´,4´/3´,5´-dimethoxyphenyl-1H-benzimidazoles were synthesized and characterized by using analytical data, FT-IR, FT-Raman, NMR, ESI-MS and fl uorescence spectroscopy. The optimized molecular geometry, zero point energy, dipole moment, ESE, band gap and charge distributions were calculated by Gaussian 09 using Density Functional Theory (DFT, RB3LYP with 6-31++G(d,p basis set. According to the calculations, the molecules have structures with various torsion angles between the benzimidazole and benzene rings from 9.7º to 47.8º. The calculated energy values with ZPE correction and DFT show that the methyl derivatives are more stable than the chloro forms. 3´,4´-Dimethoxy derivatives have higher decomposition points in comparison with the other compounds in series. The chlorine atoms of 5,6-dichloro-2- (2´,3´/2´,4´/2´,5´/3´,4´/3´,5´-dimethoxyphenyl-1H-benzimidazoles are positively charged whereas the C5 and C6 carbon atoms are negatively charged due to the attached chlorine atoms, in virtue of the electron withdrawing characteristic of the imidazole part of the benzimidazole ring. Also, some calculated prominent bond lengths and bond angles were discussed.

  20. Single-molecule pull-down (SiMPull) for new-age biochemistry: methodology and biochemical applications of single-molecule pull-down (SiMPull) for probing biomolecular interactions in crude cell extracts.

    Science.gov (United States)

    Aggarwal, Vasudha; Ha, Taekjip

    2014-11-01

    Macromolecular interactions play a central role in many biological processes. Protein-protein interactions have mostly been studied by co-immunoprecipitation, which cannot provide quantitative information on all possible molecular connections present in the complex. We will review a new approach that allows cellular proteins and biomolecular complexes to be studied in real-time at the single-molecule level. This technique is called single-molecule pull-down (SiMPull), because it integrates principles of conventional immunoprecipitation with the powerful single-molecule fluorescence microscopy. SiMPull is used to count how many of each protein is present in the physiological complexes found in cytosol and membranes. Concurrently, it serves as a single-molecule biochemical tool to perform functional studies on the pulled-down proteins. In this review, we will focus on the detailed methodology of SiMPull, its salient features and a wide range of biological applications in comparison with other biosensing tools. © 2014 WILEY Periodicals, Inc.

  1. Methyl 2-Benzamido-2-(1H-benzimidazol-1-ylmethoxyacetate

    Directory of Open Access Journals (Sweden)

    Alami Anouar

    2012-09-01

    Full Text Available The heterocyclic carboxylic α-aminoester methyl 2-benzamido-2-(1H-benzimidazol-1-ylmethoxyacetate is obtained by O-alkylation of methyl α-azido glycinate N-benzoylated with 1H-benzimidazol-1-ylmethanol.

  2. Benzimidazoles as benzamide replacements within cyclohexane-based CC chemokine receptor 2 (CCR2) antagonists.

    Science.gov (United States)

    Cherney, Robert J; Mo, Ruowei; Meyer, Dayton T; Pechulis, Anthony D; Guaciaro, Michael A; Lo, Yvonne C; Yang, Gengjie; Miller, Persymphonie B; Scherle, Peggy A; Zhao, Qihong; Cvijic, Mary Ellen; Barrish, Joel C; Decicco, Carl P; Carter, Percy H

    2012-10-01

    We describe the design, synthesis, and evaluation of benzimidazoles as benzamide replacements within a series of trisubstituted cyclohexane CCR2 antagonists. 7-Trifluoromethylbenzimidazoles displayed potent binding and functional antagonism of CCR2 while being selective over CCR3. These benzimidazoles were also incorporated into lactam-containing antagonists, thus completely eliminating the customary bis-amide. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. A bioassay for the detection of benzimidazoles reveals their presence in a range of environmental samples

    Directory of Open Access Journals (Sweden)

    Terence S Crofts

    2014-11-01

    Full Text Available Cobamides are a family of enzyme cofactors that include vitamin B12 (cobalamin and are produced solely by prokaryotes. Structural variability in the lower axial ligand has been observed in cobamides produced by diverse organisms. Of the three classes of lower ligands, the benzimidazoles are uniquely found in cobamides, whereas the purine and phenolic bases have additional biological functions. Many organisms acquire cobamides by salvaging and remodeling cobamides or their precursors from the environment. These processes require free benzimidazoles for incorporation as lower ligands, though the presence of benzimidazoles in the environment has not been previously investigated. Here, we report a new purification method and bioassay to measure the total free benzimidazole content of samples from microbial communities and laboratory media components. The bioassay relies on the calcofluor-bright phenotype of a bluB mutant of the model cobalamin-producing bacterium Sinorhizobium meliloti. The concentrations of individual benzimidazoles in these samples were measured by liquid chromatography-tandem mass spectrometry. Several benzimidazoles were detected in subpicomolar to subnanomolar concentrations in host-associated and environmental samples. In addition, benzimidazoles were found to be common contaminants of laboratory media components. These results suggest that benzimidazoles present in the environment and in laboratory media have the potential to influence microbial metabolic activities.

  4. Microwave-assisted synthesis of some nitro-benzimidazoles and their salicyl and isatin Schiff bases

    Directory of Open Access Journals (Sweden)

    F. Yılmaz

    2017-11-01

    Full Text Available A series of 5-nitrosubstituted benzimidazole and 6-nitro substituted benzimidazole derivatives were synthesized starting from iminoester hydrochloride and 4-nitro-o-phenylenediamine under microwave irradiation. The structure of newly synthesized compounds was confirmed by IR, 1H-NMR, 13C-NMR, LC-MS spectroscopy and elemental analysis.

  5. Probing into hybrid organic-molecule and InAs quantum-dots nanosystem with multistacked dots-in-a-well units

    DEFF Research Database (Denmark)

    Chen, Miaoxiang Max; Kobashi, Kazufumi

    2012-01-01

    Hybridizing air-stable organic-molecules with advanced III-V semiconductor quantum-dots (QDs) structures can be utilized to create a new generation of biochemical sensing devices. In order to enhance their optical performances, the active regions in these QDs structures commonly consist of multis......Hybridizing air-stable organic-molecules with advanced III-V semiconductor quantum-dots (QDs) structures can be utilized to create a new generation of biochemical sensing devices. In order to enhance their optical performances, the active regions in these QDs structures commonly consist...

  6. Benzimidazole acrylonitriles as multifunctional push-pull chromophores: Spectral characterisation, protonation equilibria and nanoaggregation in aqueous solutions

    Science.gov (United States)

    Horak, Ema; Vianello, Robert; Hranjec, Marijana; Krištafor, Svjetlana; Zamola, Grace Karminski; Steinberg, Ivana Murković

    2017-05-01

    Heterocyclic donor-π-acceptor molecular systems based on an N,N-dimethylamino phenylacrylonitrile benzimidazole skeleton have been characterised and are proposed for potential use in sensing applications. The benzimidazole moiety introduces a broad spectrum of useful multifunctional properties to the system including electron accepting ability, pH sensitivity and compatibility with biomolecules. The photophysical characterisation of the prototropic forms of these chromophores has been carried out in both solution and on immobilisation in polymer films. The experimental results are further supported by computational determination of pKa values. It is noticed that compound 3 forms nanoaggregates in aqueous solutions with aggregation-induced emission (AIE) at 600 nm. All the systems demonstrate spectral pH sensitivity in acidic media which shifts towards near-neutral values upon immobilisation in polymer films or upon aggregation in an aqueous environment (compound 3). The structure-property relationships of these functional chromophores, involving their spectral characteristics, acid-base equilibria, pKa values and aggregation effects have been determined. Potential applications of the molecules as pH and biomolecular sensors are proposed based on their pH sensitivity and AIE properties.

  7. Novel aminopyrimidinyl benzimidazoles as potentially antimicrobial agents: Design, synthesis and biological evaluation.

    Science.gov (United States)

    Liu, Han-Bo; Gao, Wei-Wei; Tangadanchu, Vijai Kumar Reddy; Zhou, Cheng-He; Geng, Rong-Xia

    2018-01-01

    A series of novel aminopyrimidinyl benzimidazoles as potentially antimicrobial agents were designed, synthesized and characterized by IR, NMR and HRMS spectra. The biological evaluation in vitro revealed that some of the target compounds exerted good antibacterial and antifungal activity in comparison with the reference drugs. Noticeably, compound 7d could effectively inhibit the growth of A. flavus, E. coli DH52 and MRSA with MIC values of 1, 1 and 8 μg/mL, respectively. Further studies revealed that pyrimidine derivative 7d could exhibit bactericidal mode of action against both Gram positive (S. aureus and MRSA) and Gram negative (P. aeruginosa) bacteria. The active molecule 7d showed low cell toxicity and did not obviously trigger the development of resistance in bacteria even after 16 passages. Furthermore, compound 7d was able to beneficially regulate reactive oxygen species (ROS) generation for an excellent safety profile. Molecular docking study revealed that compound 7d could bind with DNA gyrase by the formation of hydrogen bonds. The preliminary exploration for antimicrobial mechanism disclosed that compound 7d could effectively intercalate into calf thymus DNA to form a steady supramolecular complex, which might further block DNA replication to exert the powerful bioactivities. The binding investigation of compound 7d with human serum albumins (HSA) revealed that this molecule could be effectively transported by HSA. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  8. Dichlorido{2-[(5-methyl-1H-pyrazol-3-yl-κN2methyl]-1H-1,3-benzimidazole-κN3}zinc

    Directory of Open Access Journals (Sweden)

    Karim Chkirate

    2017-01-01

    Full Text Available The asymmetric unit of the title complex, [ZnCl2(C12H12N4], contains two independent molecules having similar conformations. The coordination about the ZnII atom is distorted tetrahedral, with the geometrical constraints of the chelating ligand responsible for the observed distortion. Each of the independent molecules forms chains in the crystal through pairs of N—H...Cl hydrogen bonds, using the pyrazole and benzimidazole N—H groups as donors. The first molecule forms chains running parallel to the b axis, while the other molecule affords the same kind of one-dimensional supramolecular structure parallel to the a axis. The structure was refined as a two-component twin with BASF = 0.0437 (4.

  9. Evaluation of the membrane permeability (PAMPA and skin) of benzimidazoles with potential cannabinoid activity and their relation with the Biopharmaceutics Classification System (BCS).

    Science.gov (United States)

    Alvarez-Figueroa, M Javiera; Pessoa-Mahana, C David; Palavecino-González, M Elisa; Mella-Raipán, Jaime; Espinosa-Bustos, Cristián; Lagos-Muñoz, Manuel E

    2011-06-01

    The permeability of five benzimidazole derivates with potential cannabinoid activity was determined in two models of membranes, parallel artificial membrane permeability assay (PAMPA) and skin, in order to study the relationship of the physicochemical properties of the molecules and characteristics of the membranes with the permeability defined by the Biopharmaceutics Classification System. It was established that the PAMPA intestinal absorption method is a good predictor for classifying these molecules as very permeable, independent of their thermodynamic solubility, if and only if these have a Log P(oct) value permeability is conditioned on the solubility of the molecule so that it can only serve as a model for classifying the permeability of molecules that possess high solubility (class I: high solubility, high permeability; class III: high solubility, low permeability).

  10. A Combined Probe-Molecule, Mössbauer, Nuclear Resonance Vibrational Spectroscopy, and Density Functional Theory Approach for Evaluation of Potential Iron Active Sites in an Oxygen Reduction Reaction Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Kneebone, Jared L. [Univ. of Rochester, Rochester, NY (United States); Daifuku, Stephanie L. [Univ. of Rochester, Rochester, NY (United States); Kehl, Jeffrey A. [Univ. of Rochester, Rochester, NY (United States); Wu, Gang [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chung, Hoon T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hu, Michael Y. [Argonne National Lab. (ANL), Argonne, IL (United States); Alp, E. Ercan [Argonne National Lab. (ANL), Argonne, IL (United States); More, Karren L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zelenay, Piotr [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Holby, Edward F. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Neidig, Michael L. [Univ. of Rochester, Rochester, NY (United States)

    2017-07-06

    While non-precious metal M-N-C (M = Fe or Co) catalysts have been developed that are effective for the oxygen reduction reaction in polymer electrolyte fuel cells, no consensus has yet been reached regarding the nature of the M sites in these heterogeneous catalysts that are responsible for reaction with dioxygen (O2). While multiple studies have developed correlations between Fe distributions in as-prepared catalysts and ORR activity, the direct identification of sites reactive towards O2 or O2-analog molecules remains a significant challenge. In the present study, we demonstrate a new approach to identifying and characterizing potential Fe active sites in complex ORR catalysts that combines an effective probe molecule (NO(g)) Mössbauer spectroscopy and nuclear resonance vibrational spectroscopy (NRVS) with density functional theory (DFT) calculations. Mössbauer spectroscopic studies demonstrate that NO(g) treatment of electrochemically reduced PANI-57Fe-C leads to selective reaction with only a sub-set of the Fe species present. Nuclear resonance vibrational spectroscopic studies identified new Fe-ligand vibrations associated with the site reactive towards NO(g). DFT calculations of vibrational properties of a small selection of previously proposed active site structures suggest that graphene zig-zag edge hosted Fe-N structures may be responsible for the observed vibrational behavior with NO(g) probe molecules. Moreover, such sites are likely also reactive to O2, possibly serving as the ORR active sites in the synthesized materials.

  11. Localization microscopy of DNA in situ using Vybrant{sup ®} DyeCycle™ Violet fluorescent probe: A new approach to study nuclear nanostructure at single molecule resolution

    Energy Technology Data Exchange (ETDEWEB)

    Żurek-Biesiada, Dominika [Laboratory of Cell Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków (Poland); Szczurek, Aleksander T. [Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz (Germany); Prakash, Kirti [Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz (Germany); Institute for Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, Im Neuenheimer Feld 364, D-69120 Heidelberg (Germany); Mohana, Giriram K. [Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz (Germany); Lee, Hyun-Keun [Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz (Germany); Department of Physics, University of Mainz (JGU), Staudingerweg 7, 55128 Mainz (Germany); Roignant, Jean-Yves [Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz (Germany); Birk, Udo J. [Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz (Germany); Department of Physics, University of Mainz (JGU), Staudingerweg 7, 55128 Mainz (Germany); Dobrucki, Jurek W., E-mail: jerzy.dobrucki@uj.edu.pl [Laboratory of Cell Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków (Poland); Cremer, Christoph, E-mail: c.cremer@imb-mainz.de [Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz (Germany); Institute for Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, Im Neuenheimer Feld 364, D-69120 Heidelberg (Germany); Department of Physics, University of Mainz (JGU), Staudingerweg 7, 55128 Mainz (Germany)

    2016-05-01

    Higher order chromatin structure is not only required to compact and spatially arrange long chromatids within a nucleus, but have also important functional roles, including control of gene expression and DNA processing. However, studies of chromatin nanostructures cannot be performed using conventional widefield and confocal microscopy because of the limited optical resolution. Various methods of superresolution microscopy have been described to overcome this difficulty, like structured illumination and single molecule localization microscopy. We report here that the standard DNA dye Vybrant{sup ®} DyeCycle™ Violet can be used to provide single molecule localization microscopy (SMLM) images of DNA in nuclei of fixed mammalian cells. This SMLM method enabled optical isolation and localization of large numbers of DNA-bound molecules, usually in excess of 10{sup 6} signals in one cell nucleus. The technique yielded high-quality images of nuclear DNA density, revealing subdiffraction chromatin structures of the size in the order of 100 nm; the interchromatin compartment was visualized at unprecedented optical resolution. The approach offers several advantages over previously described high resolution DNA imaging methods, including high specificity, an ability to record images using a single wavelength excitation, and a higher density of single molecule signals than reported in previous SMLM studies. The method is compatible with DNA/multicolor SMLM imaging which employs simple staining methods suited also for conventional optical microscopy. - Highlights: • Super-resolution imaging of nuclear DNA with Vybrant Violet and blue excitation. • 90nm resolution images of DNA structures in optically thick eukaryotic nuclei. • Enhanced resolution confirms the existence of DNA-free regions inside the nucleus. • Optimized imaging conditions enable multicolor super-resolution imaging.

  12. Probing DNA interactions with proteins using a single-molecule toolbox: inside the cell, in a test tube and in a computer.

    Science.gov (United States)

    Wollman, Adam J M; Miller, Helen; Zhou, Zhaokun; Leake, Mark C

    2015-04-01

    DNA-interacting proteins have roles in multiple processes, many operating as molecular machines which undergo dynamic meta-stable transitions to bring about their biological function. To fully understand this molecular heterogeneity, DNA and the proteins that bind to it must ideally be interrogated at a single molecule level in their native in vivo environments, in a time-resolved manner, fast enough to sample the molecular transitions across the free-energy landscape. Progress has been made over the past decade in utilizing cutting-edge tools of the physical sciences to address challenging biological questions concerning the function and modes of action of several different proteins which bind to DNA. These physiologically relevant assays are technically challenging but can be complemented by powerful and often more tractable in vitro experiments which confer advantages of the chemical environment with enhanced detection signal-to-noise of molecular signatures and transition events. In the present paper, we discuss a range of techniques we have developed to monitor DNA-protein interactions in vivo, in vitro and in silico. These include bespoke single-molecule fluorescence microscopy techniques to elucidate the architecture and dynamics of the bacterial replisome and the structural maintenance of bacterial chromosomes, as well as new computational tools to extract single-molecule molecular signatures from live cells to monitor stoichiometry, spatial localization and mobility in living cells. We also discuss recent developments from our laboratory made in vitro, complementing these in vivo studies, which combine optical and magnetic tweezers to manipulate and image single molecules of DNA, with and without bound protein, in a new super-resolution fluorescence microscope.

  13. Photodissociation of aligned CH3I and C6H3F2I molecules probed with time-resolved Coulomb explosion imaging by site-selective extreme ultraviolet ionization.

    Science.gov (United States)

    Amini, Kasra; Savelyev, Evgeny; Brauße, Felix; Berrah, Nora; Bomme, Cédric; Brouard, Mark; Burt, Michael; Christensen, Lauge; Düsterer, Stefan; Erk, Benjamin; Höppner, Hauke; Kierspel, Thomas; Krecinic, Faruk; Lauer, Alexandra; Lee, Jason W L; Müller, Maria; Müller, Erland; Mullins, Terence; Redlin, Harald; Schirmel, Nora; Thøgersen, Jan; Techert, Simone; Toleikis, Sven; Treusch, Rolf; Trippel, Sebastian; Ulmer, Anatoli; Vallance, Claire; Wiese, Joss; Johnsson, Per; Küpper, Jochen; Rudenko, Artem; Rouzée, Arnaud; Stapelfeldt, Henrik; Rolles, Daniel; Boll, Rebecca

    2018-01-01

    We explore time-resolved Coulomb explosion induced by intense, extreme ultraviolet (XUV) femtosecond pulses from a free-electron laser as a method to image photo-induced molecular dynamics in two molecules, iodomethane and 2,6-difluoroiodobenzene. At an excitation wavelength of 267 nm, the dominant reaction pathway in both molecules is neutral dissociation via cleavage of the carbon-iodine bond. This allows investigating the influence of the molecular environment on the absorption of an intense, femtosecond XUV pulse and the subsequent Coulomb explosion process. We find that the XUV probe pulse induces local inner-shell ionization of atomic iodine in dissociating iodomethane, in contrast to non-selective ionization of all photofragments in difluoroiodobenzene. The results reveal evidence of electron transfer from methyl and phenyl moieties to a multiply charged iodine ion. In addition, indications for ultrafast charge rearrangement on the phenyl radical are found, suggesting that time-resolved Coulomb explosion imaging is sensitive to the localization of charge in extended molecules.

  14. Passing Current through Touching Molecules

    DEFF Research Database (Denmark)

    Schull, G.; Frederiksen, Thomas; Brandbyge, Mads

    2009-01-01

    The charge flow from a single C-60 molecule to another one has been probed. The conformation and electronic states of both molecules on the contacting electrodes have been characterized using a cryogenic scanning tunneling microscope. While the contact conductance of a single molecule between two...

  15. Ionic conducting poly-benzimidazoles; Polybenzimidazoles conducteurs ioniques

    Energy Technology Data Exchange (ETDEWEB)

    Jouanneau, J

    2006-11-15

    Over the last years, many research works have been focused on new clean energy systems. Hydrogen fuel cell seems to be the most promising one. However, the large scale development of this technology is still limited by some key elements. One of them is the polymer electrolyte membrane 'Nafion' currently used, for which the ratio performance/cost is too low. The investigations we carried out during this thesis work are related to a new class of ionic conducting polymer, the sulfonated poly-benzimidazoles (sPBI). Poly-benzimidazoles (PBI) are aromatic heterocyclic polymers well-known for their excellent thermal and chemical stability. Ionic conduction properties are obtained by having strong acid groups (sulfonic acid SO{sub 3}H) on the macromolecular structure. For that purpose, we first synthesized sulfonated monomers. Their poly-condensation with an appropriate non-sulfonated co-monomer yields to sPBI with sulfonation range from 0 to 100 per cent. Three different sPBI structures were obtained, and verified by appropriate analytical techniques. We also showed that the protocol used for the synthesis resulted in high molecular weights polymers. We prepared ionic conducting membrane by casting sPBI solutions on glass plates. Their properties of stability, water swelling and ionic conductivity were investigated. Surprisingly, the behaviour of sPBI was quite different from the other sulfonated aromatic polymers with same amount of SO{sub 3}H, their stability was much higher, but their water swelling and ionic conductivity were quite low. We attributed these differences to strong ionic interactions between the sulfonic acid groups and the basic benzimidazole groups of our polymers. However, we managed to solve this problem synthesizing very highly sulfonated PBI, obtaining membranes with a good balance between all the properties necessary. (author)

  16. Steady state and time-resolved spectroscopic investigations on the photoreactions involved within the electronically excited electron acceptor 9-cyanoanthracene in presence of benzotriazole and benzimidazole donors

    International Nuclear Information System (INIS)

    Bhattacharya, Sudeshna; Bardhan, Munmun; Ganguly, Tapan

    2010-01-01

    The electrochemical, 'steady-state' and 'time-resolved' spectroscopic investigations were made on the well-known electron acceptor 9-cyanoanthracene (CNA) when interacted with the electron donors benzotriazole (BZT) and benzimidazole (BMI) molecules. Though electrochemical measurements indicate the thermodynamical possibility of occurrences of photoinduced electron transfer reactions within these reacting systems in the lowest excited singlet state (S 1 ) of the acceptor CNA but the steady-state and time-resolved measurements clearly demonstrate only the triplet-initiated charge separation reactions. It was reported earlier that in the cases of disubstituted indole molecules the occurrences of photoinduced electron transfer reactions were apparent both in the excited singlet and triplet states of the acceptor 9-cyanoanthracene, but the similarly structured present donor molecules benzotriazole (and benzimidazole) behave differently from indoles. The weak ground state complex formations within the presently studied reacting systems appear to be responsible for the observed static quenching phenomena as evidenced from the time-resolved fluorescence studies. Time-resolved spectroscopic investigations demonstrate the formation of the ground state of the reacting components (donor and acceptor) through recombination of triplet ion-pairs via formations of contact neutral radical produced by H-abstraction mechanism.

  17. Optical, thermal and electrical properties of polybenzimidazoles derived from substituted benzimidazoles

    Science.gov (United States)

    Anand, Siddeswaran; Muthusamy, Athianna

    2017-11-01

    Three benzimidazole monomers synthesized by condensing various substituted phenolic aldehydes with 4-methylphenylenediamine were converted in to polymers by oxidative polycondensation. The structure of the monomers and polymers were confirmed by various spectroscopic techniques. Electronic distribution of molecular frontier orbitals and optimized geometries of monomers were calculated by Gaussian 09 package. The spectral results showed that the repeating units are connected through both Csbnd C and Csbnd Osbnd C linkages. Both polymers and monomers are showing good fluorescence emission in blue region. The electrical conductivity of I2 doped PBIs was measured using two point probe technique. The conductivities of PBIs were compared on the basis of the charge densities obtained from Huckel method on imidazole nitrogen which is involved in iodine coordination. The conductivity of polymers increases with increase in iodine vapour contact time. The dielectric properties of the synthesized polymers have been investigated at different temperature and frequency. Among the PBIs, PBIOP is having greater thermal stability and is shown by high carbines residues of around 50% at 500 °C in thermogravimetric analysis.

  18. Synthesis of Benzimidazole Derivatives: As Anti-hypertensive Agents

    Directory of Open Access Journals (Sweden)

    Jat Rakesh Kumar

    2006-01-01

    Full Text Available A new series of non peptide angiotensin(A-II receptor antagonist has been prepared. This N-(biphenyl methyl imidazoles e.g. 5-substituted (amino -2- phenyl-1-(2ʼcarboxy biphenyl-4-yl benzimidazoles differ from the previously reported and related compounds in that they produce a potent hypertensive effect upon oral administration. The earlier series were generally active only when administered intravenously. It has been found that 2’-position of biphenyl is essential. Only ortho substituted acid possess both high affinity for the AII receptor and oral anti-hypertensive potency.

  19. Pulse radiolysis of 2-mercapto benzimidazole in aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Dey, G R; Naik, D B; Kishore, K; Moorthy, P N [Bhabha Atomic Research Centre, Bombay (India). Applied Chemistry Division

    1994-12-31

    The initial e{sub aq}{sup -}/H adducts of 2-mercapto benzimidazole(MBZ) ({lambda}{sub max} {approx} 370 nm) which are mild reductants react with parent compound to give an intermolecular 3-electron bonded species with {lambda}{sub max} at 590 nm. The rate constants for the reactions of MBZ with e{sub aq}{sup -} and OH radicals at pH 7 and with H-atoms at pH 2 were determined. OH radical reaction with MBZ gives an intramolecular 3-electron bonded species. (author). 2 refs., 2 figs., 1 tab.

  20. SMM-chemokines: a class of unnatural synthetic molecules as chemical probes of chemokine receptor biology and leads for therapeutic development.

    Science.gov (United States)

    Kumar, Santosh; Choi, Won-Tak; Dong, Chang-Zhi; Madani, Navid; Tian, Shaomin; Liu, Dongxiang; Wang, Youli; Pesavento, James; Wang, Jun; Fan, Xuejun; Yuan, Jian; Fritzsche, Wayne R; An, Jing; Sodroski, Joseph G; Richman, Douglas D; Huang, Ziwei

    2006-01-01

    Chemokines and their receptors play important roles in numerous physiological and pathological processes. To develop natural chemokines into receptor probes and inhibitors of pathological processes, the lack of chemokine-receptor selectivity must be overcome. Here, we apply chemical synthesis and the concept of modular modifications to generate unnatural synthetically and modularly modified (SMM)-chemokines that have high receptor selectivity and affinity, and reduced toxicity. A proof of the concept was shown by transforming the nonselective viral macrophage inflammatory protein-II into new analogs with enhanced selectivity and potency for CXCR4 or CCR5, two principal coreceptors for human immunodeficiency virus (HIV)-1 entry. These new analogs provided insights into receptor binding and signaling mechanisms and acted as potent HIV-1 inhibitors. These results support the concept of SMM-chemokines for studying and controlling the function of other chemokine receptors.

  1. Structure-activity relations of 2-(methylthio)benzimidazole by FTIR, FT-Raman, NMR, DFT and conceptual DFT methods.

    Science.gov (United States)

    Arjunan, V; Raj, Arushma; Ravindran, P; Mohan, S

    2014-01-24

    The vibrational fundamental modes of 2-(methylthio)benzimidazole (2MTBI) have been analysed by combining FTIR, FT-Raman and quantum chemical calculations. The structural parameters of the compound are determined from the optimised geometry by B3LYP with 6-31G(∗∗), 6-311++G(∗∗) and cc-pVTZ basis sets and giving energies, harmonic vibrational frequencies, depolarisation ratios, IR intensities and Raman activities. (1)H and (13)C NMR spectra have been analysed and (1)H and (13)C nuclear magnetic resonance chemical shifts are calculated using the gauge independent atomic orbital (GIAO) method. The structure-activity relationship of the compound is also investigated by conceptual DFT methods. The chemical reactivity and site selectivity of the molecule has been determined with the help of global and local reactivity descriptors. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. (Salicylato[tris(1-methyl-1H-benzimidazol-2-ylmethylamine]copper(II perchlorate dimethylformamide disolvate

    Directory of Open Access Journals (Sweden)

    Huilu Wu

    2008-01-01

    Full Text Available In the title complex, [Cu(C7H5O3(C27H27N7]ClO4·2C3H7NO, the CuII ion is five-coordinated by four N atoms from the tris(1-methyl-1H-benzimidazol-2-ylmethylamine ligand and an O atom of the monodentate salicylate ligand. The N4O donor set defines a coordination geometry intermediate between square-pyramidal and trigonal–bipyramidal. The crystal structure is stabilized by O—H...O interactions. The atoms of the aromatic ring of the salicylate ligand are disordered over two sites of equal occupancy. In addition, one of the dimethylformamide solvent molecules is partially disordered over two positions, of approximately equal occupancy.

  3. Probing into hybrid organic-molecule and InAs quantum-dots nanosystem with multistacked dots-in-a-well units

    Science.gov (United States)

    Chen, Miaoxiang; Kobashi, Kazufumi

    2012-09-01

    Hybridizing air-stable organic-molecules with advanced III-V semiconductor quantum-dots (QDs) structures can be utilized to create a new generation of biochemical sensing devices. In order to enhance their optical performances, the active regions in these QDs structures commonly consist of multistacked dots-in-a-well (DWELL) units. The effects of grafted molecules on the performances of the QDs structures with multistacked DWELLs, however, still remain unclear. Here, we show the significant improvements in the optical properties of InAs QDs in a hybrid nanosystem obtained by grafting biocompatible diazonium salt compound (amine donor) atop InAs QDs structure. Since its interface between the QDs structure and molecular monolayer retains an uncontaminated and non-oxidized condition, the nanosystem is an ideal platform to study the intrinsic properties of charge-carrier transport inside the system. Because of the complexity of the energy-levels in the QDs structure due to the existing surface QDs and DWELLs, selective excitation wavelengths (400, 633, and 885 nm, respectively) with different photo-energies are used to exactly analyze the complete charging mechanism in these QDs. A clear view of charge-carrier transfer inside the nanosystem is revealed by employing photoluminescence technique under selective-wavelength excitations. The present work provides new quantitative evidences for exploiting inorganic QDs applications in complex biological systems.

  4. Probing into hybrid organic-molecule and InAs quantum-dots nanosystem with multistacked dots-in-a-well units

    Energy Technology Data Exchange (ETDEWEB)

    Chen Miaoxiang [Department of Micro- and Nano technology, Technical University of Denmark, Orsteds Plads, 2800 Kgs. Lyngby (Denmark); Kobashi, Kazufumi [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 (Japan)

    2012-09-15

    Hybridizing air-stable organic-molecules with advanced III-V semiconductor quantum-dots (QDs) structures can be utilized to create a new generation of biochemical sensing devices. In order to enhance their optical performances, the active regions in these QDs structures commonly consist of multistacked dots-in-a-well (DWELL) units. The effects of grafted molecules on the performances of the QDs structures with multistacked DWELLs, however, still remain unclear. Here, we show the significant improvements in the optical properties of InAs QDs in a hybrid nanosystem obtained by grafting biocompatible diazonium salt compound (amine donor) atop InAs QDs structure. Since its interface between the QDs structure and molecular monolayer retains an uncontaminated and non-oxidized condition, the nanosystem is an ideal platform to study the intrinsic properties of charge-carrier transport inside the system. Because of the complexity of the energy-levels in the QDs structure due to the existing surface QDs and DWELLs, selective excitation wavelengths (400, 633, and 885 nm, respectively) with different photo-energies are used to exactly analyze the complete charging mechanism in these QDs. A clear view of charge-carrier transfer inside the nanosystem is revealed by employing photoluminescence technique under selective-wavelength excitations. The present work provides new quantitative evidences for exploiting inorganic QDs applications in complex biological systems.

  5. A single molecule assay to probe monovalent and multivalent bonds between hyaluronan and its key leukocyte receptor CD44 under force

    Science.gov (United States)

    Bano, Fouzia; Banerji, Suneale; Howarth, Mark; Jackson, David G.; Richter, Ralf P.

    2016-09-01

    Glycosaminoglycans (GAGs), a category of linear, anionic polysaccharides, are ubiquitous in the extracellular space, and important extrinsic regulators of cell function. Despite the recognized significance of mechanical stimuli in cellular communication, however, only few single molecule methods are currently available to study how monovalent and multivalent GAG·protein bonds respond to directed mechanical forces. Here, we have devised such a method, by combining purpose-designed surfaces that afford immobilization of GAGs and receptors at controlled nanoscale organizations with single molecule force spectroscopy (SMFS). We apply the method to study the interaction of the GAG polymer hyaluronan (HA) with CD44, its receptor in vascular endothelium. Individual bonds between HA and CD44 are remarkably resistant to rupture under force in comparison to their low binding affinity. Multiple bonds along a single HA chain rupture sequentially and independently under load. We also demonstrate how strong non-covalent bonds, which are versatile for controlled protein and GAG immobilization, can be effectively used as molecular anchors in SMFS. We thus establish a versatile method for analyzing the nanomechanics of GAG·protein interactions at the level of single GAG chains, which provides new molecular-level insight into the role of mechanical forces in the assembly and function of GAG-rich extracellular matrices.

  6. Characterisation of the acidity and the basicity of transition alumina by NMR and FTIR spectroscopy of adsorption of probe molecules; Caracterisation par RMN et infrarouge de molecules sondes adsorbees, de l'acidite et de la basicite d'alumines de transition

    Energy Technology Data Exchange (ETDEWEB)

    Mathonneau, E.

    2003-04-01

    This work has been devoted to characterization of the acidity and the basicity of the surface of transition alumina. Three different alumina (Alumina-{gamma}, -{delta} et -{theta} ({gamma}-Al, {delta}-Al, {theta}-Al)) have been studied by adsorption of probe molecules such trimethyl phosphine and carbon monoxide (acidity study); and tri-ethyl borane (basicity study). We emphasized that the acidity increases with an increasing pretreatment temperature where as the basicity decreases. Comparing quantitative results from the different probe molecules we could show an increasing strength acidity following: {gamma}-Al > {theta}-Al > {delta}-Al, and basicity following: {delta}-Al > {gamma}-Al > {theta}-Al. We could evaluate on a qualitative (nature and repartition) and on a quantitative point of view the impact of the transformations {gamma}-Al {yields} {delta}-Al and {gamma}-Al > {theta}-Al on the acid-basicity of the surface. We could also explain catalytic reactivity differences between alumina for the position isomerization of butene-1. (author)

  7. Multifunctional Poly(2,5-benzimidazole)/Carbon Nanotube Composite Films

    Science.gov (United States)

    2010-01-01

    Multifunctional Poly(2,5- benzimidazole )/Carbon Nanotube Composite Films JI-YE KANG,1 SOO-MI EO,1 IN-YUP JEON,1 YEONG SUK CHOI,2 LOON-SENG TAN,3 JONG...molecular-weight poly(2,5- benzimidazole ) (ABPBI). ABPBI/carbon nanotube (CNT) compo- sites were prepared via in situ polymerization of the AB-monomer in the...polymerization; multiwalled carbon nanotube (MWCNT); nano- composites; poly(2,5- benzimidazole ); (ABPBI); polycondensa- tion; poly(phosphoric acid); single-walled

  8. Benzimidazole as corrosion inhibitor for heat treated 6061 Al- SiCp composite in acetic acid

    International Nuclear Information System (INIS)

    Chacko, Melby; Nayak, Jagannath

    2015-01-01

    6061 Al-SiCpcomposite was solutionizedat 350 °C for 30 minutes and water quenched. It was then underaged at 140 °C (T6 treatment). The aging behaviour of the composite was studied using Rockwell B hardness measurement. Corrosion behaviour of the underaged sample was studied in different concentrations of acetic acid and at different temperatures. Benzimidazole at different concentrations was used for the inhibition studies. Inhibition efficiency of benzimidazole was calculated for different experimental conditions. Thermodynamic parameters were found out which suggested benzimidazole is an efficient inhibitor and it adsorbed on to the surface of composite by mixed adsorption where chemisorption is predominant. (paper)

  9. Probing the role of metal cations on the aggregation behavior of amyloid β-peptide at a single molecule level by AFM

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yang; Wang, Jianhua, E-mail: wjh@cqu.edu.cn; Liu, Chundong [Chongqing University, Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering (China)

    2016-09-15

    With the development of nanotechnology, understanding of intermolecular interactions on a single molecule level by atomic force spectroscopy (AFM) has played an important role in molecular biology and biomedical science. In recent years, some research suggested that the presence of metal cations is an important regulator in the processes of misfolding and aggregation of the amyloid β-protein (Aβ), which may be an important etiological factor of Alzheimer’s disease. However, the knowledge on the principle of interactions between Aβ and metal cations at the single molecule level is still poor understood. In this paper, the amyloid β-protein (Aβ) was fabricated on substrate of mixed thiol-modified gold nanoparticles using self-assembled monolayer method and the adhesion force in the longitudinal direction between metal cations and Aβ42 were investigated by AFM. The role of metal ions on Aβ aggregation is discussed from the perspective of single molecular force. The force results showed that the specific adhesion force F{sub i} and the nonspecific force F{sub 0} between a single Aβ–Aβ pair in control experiment were calculated as 42 ± 3 and 80 pN, respectively. However, F{sub i} between a single Aβ–Aβ pair in the presence of Cu{sup 2+}, Zn{sup 2+}, Ca{sup 2+} and Al{sup 3+} increased dramatically to 84 ± 6, 89 ± 3, 73 ± 5, 95 ± 5 pN successively, which indicated that unbinding between Aβ proteins is accelerated in the presence of metal cations. What is more, the imaging results showed that substoichiometric copper cations accelerate the formation of fibrils within 3 days. The combined atomic force spectroscopy and imaging analysis indicate that metal cations play a role in promoting the aggregating behavior of Aβ42.

  10. Probing the role of metal cations on the aggregation behavior of amyloid β-peptide at a single molecule level by AFM

    Science.gov (United States)

    Xie, Yang; Wang, Jianhua; Liu, Chundong

    2016-09-01

    With the development of nanotechnology, understanding of intermolecular interactions on a single molecule level by atomic force spectroscopy (AFM) has played an important role in molecular biology and biomedical science. In recent years, some research suggested that the presence of metal cations is an important regulator in the processes of misfolding and aggregation of the amyloid β-protein (Aβ), which may be an important etiological factor of Alzheimer's disease. However, the knowledge on the principle of interactions between Aβ and metal cations at the single molecule level is still poor understood. In this paper, the amyloid β-protein (Aβ) was fabricated on substrate of mixed thiol-modified gold nanoparticles using self-assembled monolayer method and the adhesion force in the longitudinal direction between metal cations and Aβ42 were investigated by AFM. The role of metal ions on Aβ aggregation is discussed from the perspective of single molecular force. The force results showed that the specific adhesion force F i and the nonspecific force F 0 between a single Aβ-Aβ pair in control experiment were calculated as 42 ± 3 and 80 pN, respectively. However, F i between a single Aβ-Aβ pair in the presence of Cu2+, Zn2+, Ca2+ and Al3+ increased dramatically to 84 ± 6, 89 ± 3, 73 ± 5, 95 ± 5 pN successively, which indicated that unbinding between Aβ proteins is accelerated in the presence of metal cations. What is more, the imaging results showed that substoichiometric copper cations accelerate the formation of fibrils within 3 days. The combined atomic force spectroscopy and imaging analysis indicate that metal cations play a role in promoting the aggregating behavior of Aβ42.

  11. Probing the role of metal cations on the aggregation behavior of amyloid β-peptide at a single molecule level by AFM

    International Nuclear Information System (INIS)

    Xie, Yang; Wang, Jianhua; Liu, Chundong

    2016-01-01

    With the development of nanotechnology, understanding of intermolecular interactions on a single molecule level by atomic force spectroscopy (AFM) has played an important role in molecular biology and biomedical science. In recent years, some research suggested that the presence of metal cations is an important regulator in the processes of misfolding and aggregation of the amyloid β-protein (Aβ), which may be an important etiological factor of Alzheimer’s disease. However, the knowledge on the principle of interactions between Aβ and metal cations at the single molecule level is still poor understood. In this paper, the amyloid β-protein (Aβ) was fabricated on substrate of mixed thiol-modified gold nanoparticles using self-assembled monolayer method and the adhesion force in the longitudinal direction between metal cations and Aβ42 were investigated by AFM. The role of metal ions on Aβ aggregation is discussed from the perspective of single molecular force. The force results showed that the specific adhesion force F_i and the nonspecific force F_0 between a single Aβ–Aβ pair in control experiment were calculated as 42 ± 3 and 80 pN, respectively. However, F_i between a single Aβ–Aβ pair in the presence of Cu"2"+, Zn"2"+, Ca"2"+ and Al"3"+ increased dramatically to 84 ± 6, 89 ± 3, 73 ± 5, 95 ± 5 pN successively, which indicated that unbinding between Aβ proteins is accelerated in the presence of metal cations. What is more, the imaging results showed that substoichiometric copper cations accelerate the formation of fibrils within 3 days. The combined atomic force spectroscopy and imaging analysis indicate that metal cations play a role in promoting the aggregating behavior of Aβ42.

  12. Mannich-Benzimidazole Derivatives as Antioxidant and Anticholinesterase Inhibitors: Synthesis, Biological Evaluations, and Molecular Docking Study.

    Science.gov (United States)

    Alpan, Ayşe Selcen; Sarıkaya, Görkem; Çoban, Güneş; Parlar, Sülünay; Armagan, Güliz; Alptüzün, Vildan

    2017-07-01

    A series of Mannich bases of benzimidazole derivatives having a phenolic group were designed to assess their anticholinesterase and antioxidant activities. The acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities were evaluated in vitro by using Ellman's method. According to the activity results, all of the compounds exhibited moderate to good AChE inhibitory activity (except for 2a), with IC 50 values ranging from 0.93 to 10.85 μM, and generally displayed moderate BuChE inhibitory activity. Also, most of the compounds were selective against BuChE. Compound 4b was the most active molecule on the AChE enzyme and also selective. In addition, we investigated the antioxidant effects of the synthesized compounds against FeCl 2 /ascorbic acid-induced oxidative stress in the rat brain in vitro, and the activity results showed that most of the compounds are effective as radical scavengers. Molecular docking studies and molecular dynamics simulations were also carried out. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. A Benzimidazole Proton Pump Inhibitor Increases Growth and Tolerance to Salt Stress in Tomato

    Directory of Open Access Journals (Sweden)

    Michael J. Van Oosten

    2017-07-01

    Full Text Available Pre-treatment of tomato plants with micromolar concentrations of omeprazole (OP, a benzimidazole proton pump inhibitor in mammalian systems, improves plant growth in terms of fresh weight of shoot and roots by 49 and 55% and dry weight by 54 and 105% under salt stress conditions (200 mM NaCl, respectively. Assessment of gas exchange, ion distribution, and gene expression profile in different organs strongly indicates that OP interferes with key components of the stress adaptation machinery, including hormonal control of root development (improving length and branching, protection of the photosynthetic system (improving quantum yield of photosystem II and regulation of ion homeostasis (improving the K+:Na+ ratio in leaves and roots. To our knowledge OP is one of the few known molecules that at micromolar concentrations manifests a dual function as growth enhancer and salt stress protectant. Therefore, OP can be used as new inducer of stress tolerance to better understand molecular and physiological stress adaptation paths in plants and to design new products to improve crop performance under suboptimal growth conditions.Highlight: Omeprazole enhances growth of tomato and increases tolerance to salinity stress through alterations of gene expression and ion uptake and transport.

  14. Modification of the radiation sensitivity of human tumour cells by a bis-benzimidazole derivative

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P J; Anderson, C O [Medical Research Council, Cambridge (UK)

    1984-10-01

    A comparison was made of the ability of either X-radiation or a DNA-specific ligand (the vital bis-benzimidazole dye; Hoechst 33342) to induce: cell killing, inhibition of de novo DNA synthesis, DNA strand breakage and the delay of cell division in human colon adenocarcinoma cells in vitro. Unlike radiation-induced cell killing, ligand-induced cytotoxicity appeared to be positively correlated with the extent of inhibition of de novo DNA synthesis-a feature consistent with the persistent binding of ligand molecules to nuclear DNA. Ligand-induced DNA strand-breaks disappeared slowly although ligand-treated cells retained apparently normal capacities to repair discrete radiogenic DNA strand-breaks. Pre-treatment of cells with Hoechst 33342 resulted in a dose-modifying enhancement of radiation resistance not associated with altered dosimetry for strand-break induction. However, radioresistance was accompanied by the protracted retention of cells in the G/sub 2/ phase of the cell cycle. We suggest that the results provide direct evidence that the retention of cells in G/sub 2/ phase is a sparing phenomenon and is triggered by the responses of chromatin domains to the presence of DNA damage.

  15. In Vitro Pharmacodynamics of Benzimidazole and Tetrahydropyrimidine Derivatives in European Bison Gastro-Intestinal Nematodes

    Directory of Open Access Journals (Sweden)

    Laura CĂTANĂ

    2017-11-01

    Full Text Available The present study was aimed to evaluate the efficacy of anthelmintic agents against intestinal nematodes found in European bison. It was performed between October 2016 and May 2017, using Egg Hatch Assay (EHA and Larval Development Assay (LDA. The parasites were obtained from faecal samples, harvested from bisons in Romania and Sweden. The efficacy of albendazole (ABZ, mebendazole (MBZ thiabendazole (TBZ and pyrantel (PYR was tested. In EHA, the maximum efficacy was observed in MBZ (EC50 = - 0.227 μg/ml, and then TBZ (EC50 = - 0.2228. ABZ had a weaker result, EC50 being 0.326 μg/ml. All tested benzimidazoles registered hatching percentages below 50%, reflecting the lack of parasitic resistance. MIC obtained in the LDA tests were 0.2144 μg/ml for TBZ, 0.2792 μg/ml for PYR, 0.5429 μg/ml for MBZ, while ABZ came last (MIC = 0.8187 μg/ml. The in vitro tests proved the antiparasitic molecules efficacy against bisons nematode population and a limited risk of inducing resistance phenomena.

  16. Triaryl Benzimidazoles as a New Class of Antibacterial Agents against Resistant Pathogenic Microorganisms.

    Science.gov (United States)

    Picconi, Pietro; Hind, Charlotte; Jamshidi, Shirin; Nahar, Kazi; Clifford, Melanie; Wand, Matthew E; Sutton, J Mark; Rahman, Khondaker Miraz

    2017-07-27

    A new class of nontoxic triaryl benzimidazole compounds, derived from existing classes of DNA minor groove binders, were designed, synthesized, and evaluated for their antibacterial activity against multidrug resistant (MDR) Gram-positive and Gram-negative species. Molecular modeling experiments suggest that the newly synthesized class cannot be accommodated within the minor groove of DNA due to a change in the shape of the molecules. Compounds 8, 13, and 14 were found to be the most active of the series, with MICs in the range of 0.5-4 μg/mL against the MDR Staphylococci and Enterococci species. Compound 13 showed moderate activity against the MDR Gram-negative strains, with MICs in the range of 16-32 μg/mL. Active compounds showed a bactericidal mode of action, and a mechanistic study suggested the inhibition of bacterial gyrase as the mechanism of action (MOA) of this chemical class. The MOA was further supported by the molecular modeling study.

  17. Antimalarial pyrido[1,2-a]benzimidazoles.

    Science.gov (United States)

    Ndakala, Albert J; Gessner, Richard K; Gitari, Patricia W; October, Natasha; White, Karen L; Hudson, Alan; Fakorede, Foluke; Shackleford, David M; Kaiser, Marcel; Yeates, Clive; Charman, Susan A; Chibale, Kelly

    2011-07-14

    A novel class of antimalarial pyrido[1,2-a]benzimidazoles were synthesized and evaluated for antiplasmodial activity and cytotoxicity following hits identified from screening commercially available compound collections. The most active of these, TDR86919 (4c), showed improved in vitro activity vs the drug-resistant K1 strain of Plasmodium falciparum relative to chloroquine (IC(50) = 0.047 μM v 0.17 μM); potency was retained against a range of drug-sensitive and drug-resistant strains, with negligible cytotoxicity against the mammalian (L-6) cell line (selectivity index of >600). 4c and several close analogues (as HCl or mesylate salts) showed significant efficacy in P. berghei infected mice following both intraperitoneal (ip) and oral (po) administration, with >90% inhibition of parasitemia, accompanied by an increase in the mean survival time (MSD). The pyrido[1,2-a]benzimidazoles appeared to be relatively slow acting in vivo compared to chloroquine, and metabolic stability of the alkylamino side chain was identified as a key issue in influencing in vivo activity.

  18. Direction of Intercalation of a bis-Ru(II) Complex to DNA Probed by a Minor Groove Binding Molecule 4',6-Diamidino-2-phenylindole

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Yoon Jung; Kim, Raeyeong; Chitrapriya, Nataraj; Kim, Seog K.; Bae, Inho [Yeungnam Univ., Gyeongsan (Korea, Republic of)

    2013-10-15

    Direction of intercalation to DNA of the planar dipyrido[3,2-a:2',3'-c]phenazine ligands (dppz) of a bis-Ru(II) complex namely, [Ru(1,10-phenanthroline){sub 2}dipyrido[3,2-a:2',3'-c]phenazine]{sup 2+} linkered by a 1,3-bis(4-pyridyl)propane, was investigated by probing the behavior of 4',6-diamidino-2-phenylindole (DAPI) that bound deep in the minor groove. Bis-intercalation of DPPZ resulted in a little blue shift and hyperchromism in DAPI absorption band, and a large decrease in DAPI fluorescence intensity which accompanied by an increase in the dppz emission intensity. Diminishing the intensity of the positive induced circular dichroism (CD) and linear dichroism (LD) were also observed. These spectral changes indicated that insertion of dppz ligand caused the change of the binding mode of DAPI, which probably moved to the exterior of DNA from the minor groove and interacted with the phospghate groups of DNA by electrostatic interaction. At the surface of DNA, DAPI binds at the phosphate groups of DNA by electrostatic attraction. Consequently, this observation indicated that the dppz ligand intercalated from the minor groove.

  19. Mobile Probing and Probes

    DEFF Research Database (Denmark)

    Duvaa, Uffe; Ørngreen, Rikke; Weinkouff Mathiasen, Anne-Gitte

    2013-01-01

    Mobile probing is a method, developed for learning about digital work situations, as an approach to discover new grounds. The method can be used when there is a need to know more about users and their work with certain tasks, but where users at the same time are distributed (in time and space......). Mobile probing was inspired by the cultural probe method, and was influenced by qualitative interview and inquiry approaches. The method has been used in two subsequent projects, involving school children (young adults at 15-17 years old) and employees (adults) in a consultancy company. Findings point...... to mobile probing being a flexible method for uncovering the unknowns, as a way of getting rich data to the analysis and design phases. On the other hand it is difficult to engage users to give in depth explanations, which seem easier in synchronous dialogs (whether online or face2face). The development...

  20. Mobile Probing and Probes

    DEFF Research Database (Denmark)

    Duvaa, Uffe; Ørngreen, Rikke; Weinkouff, Anne-Gitte

    2012-01-01

    Mobile probing is a method, which has been developed for learning about digital work situations, as an approach to discover new grounds. The method can be used when there is a need to know more about users and their work with certain tasks, but where users at the same time are distributed (in time...... and space). Mobile probing was inspired by the cultural probe method, and was influenced by qualitative interview and inquiry approaches. The method has been used in two subsequent projects, involving school children (young adults at 15-17 years old) and employees (adults) in a consultancy company. Findings...... point to mobile probing being a flexible method for uncovering the unknowns, as a way of getting rich data to the analysis and design phases. On the other hand it is difficult to engage users to give in depth explanations, which seem easier in synchronous dialogs (whether online or face2face...

  1. Investigation of REE perchlorates complexing with benzimidazole in aqua-dioxane media

    International Nuclear Information System (INIS)

    Akhrimenko, Z.M.; Panyushkin, V.T.; Ishbulatova, S.K.

    1992-01-01

    Stability constant (K 1 ) of complexes of rare earth perchlorates with benzimidazole were determined by the method of pH-metric titration. Nonmonotonous change in lgK 1 with rare earth ordinal number increase was revealed

  2. Efficient fluorescent deep-blue and hybrid white emitting devices based on carbazole/benzimidazole compound

    KAUST Repository

    Yang, Xiaohui; Zheng, Shijun; Bottger, Rebecca; Chae, HyunSik; Tanaka, Takeshi; Li, Sheng; Mochizuki, Amane; Jabbour, Ghassan E.

    2011-01-01

    We report the synthesis, photophysics, and electrochemical characterization of carbazole/benzimidazole-based compound (Cz-2pbb) and efficient fluorescent deep-blue light emitting devices based on Cz-2pbb with the peak external quantum efficiency

  3. Transport of anthelmintic benzimidazole drugs by breast cancer resistance protein (BCRP/ABCG2)

    NARCIS (Netherlands)

    Merino, G; Jonker, JW; Wagenaar, E; Pulido, MM; Molina, AJ; Alvarez, AI; Schinkel, AH

    Methylcarbamate benzimidazoles [albendazole (ABZ), fenbendazole (FBZ), and their respective sulfoxide derivatives, albendazole sulfoxide (ABZSO) and oxfendazole (OXF)] are therapeutically important anthelmintic agents with low bioavailability. We studied their in vitro interaction with the apical

  4. Fixation of carbon dioxide into dimethyl carbonate over titanium-based zeolitic thiophene-benzimidazolate framework

    Data.gov (United States)

    U.S. Environmental Protection Agency — A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon...

  5. L-shaped benzimidazole fluorophores: synthesis, characterization and optical response to bases, acids and anions.

    Science.gov (United States)

    Lirag, Rio Carlo; Le, Ha T M; Miljanić, Ognjen Š

    2013-05-14

    Nine L-shaped benzimidazole fluorophores have been synthesized, computationally evaluated and spectroscopically characterized. These "half-cruciform" fluorophores respond to bases, acids and anions through changes in fluorescence that vary from moderate to dramatic.

  6. Benzimidazole for the prevention of toxic effects of air pollutants on plants

    Energy Technology Data Exchange (ETDEWEB)

    Takaoka, I; Fukuda, M; Kitano, H; Shinohara, T

    1974-02-02

    Tobacco plants were sprayed with benzimidazole before being exposed to 30 ppM of photochemical oxidants for a period of two hours. The plants were observed 48 hours after exposure and found to have suffered no toxic effects from the oxidants. It may be concluded that benzimidazole is an effective agent for preventing the toxic effects of air pollutants, such as photochemical oxidants on plants.

  7. Study of the 14C benzimidazole distribution in mice after inter-peritoneal injection

    International Nuclear Information System (INIS)

    Tyortyalian, C.

    1965-01-01

    In order to provide further information on the mechanism of benzimidazole radioprotective activity, this work studies the tissual repartition in mice of this compound labelled with carbon 14. Experiments have showed that benzimidazole distribution is fast and homogeneous in all the tissues, but however affinity appears at the level of stomach and gastric content. Elimination is made through the urinary system and is very fast. (author) [fr

  8. Single molecule force spectroscopy for in-situ probing oridonin inhibited ROS-mediated EGF-EGFR interactions in living KYSE-150 cells.

    Science.gov (United States)

    Pi, Jiang; Jin, Hua; Jiang, Jinhuan; Yang, Fen; Cai, Huaihong; Yang, Peihui; Cai, Jiye; Chen, Zheng W

    2017-05-01

    As the active anticancer component of Rabdosia Rubescens, oridonin has been proved to show strong anticancer activity in cancer cells, which is also found to be closely related to its specific inhibition effects on the EGFR tyrosine kinase activity. In this study, atomic force microscopy based single molecule force spectroscopy (AFM-SMFS) was used for real-time and in-situ detection of EGF-EGFR interactions in living esophageal cancer KYSE-150 cells to evaluate the anticancer activity of oridonin for the first time. Oridonin was found to induce apoptosis and also reduce EGFR expression in KYSE-150 cells. AFM-SMFS results demonstrated that oridonin could inhibit the binding between EGF and EGFR in KYSE-150 cells by decreasing the unbinding force and binding probability for EGF-EGFR complexes, which was further proved to be closely associated with the intracellular ROS level. More precise mechanism studies based on AFM-SMFS demonstrated that oridonin treatment could decrease the energy barrier width, increase the dissociation off rate constant and decrease the activation energy of EGF-EGFR complexes in ROS dependent way, suggesting oridonin as a strong anticancer agent targeting EGF-EGFR interactions in cancer cells through ROS dependent mechanism. Our results not only suggested oridonin as a strong anticancer agent targeting EGF-EGFR interactions in ROS dependent mechanism, but also highlighted AFM-SMFS as a powerful technique for pharmacodynamic studies by detecting ligand-receptor interactions, which was also expected to be developed into a promising tool for the screening and mechanism studies of drugs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Oxidative polycondensation of benzimidazole using NaOCl: Synthesis, characterization, optical, thermal and electrical properties of polybenzimidazoles

    Science.gov (United States)

    Anand, Siddeswaran; Muthusamy, Athianna; Dineshkumar, Sengottuvelu; Chandrasekaran, J.

    2017-11-01

    A series of polybenzimidazole polymers, poly-2-(1H-benzo[d] imidazole-2-yl) phenol (PBIP2), poly-3-(1H-benzo[d] imidazole-2-yl) phenol (PBIP3) and poly-4-(1H-benzo[d] imidazole-2-yl) phenol (PBIP4) were synthesized by oxidative polycondensation of benzimidazole monomers 2-(1H-benzo [d] imidazole-2-yl) phenol (BIP2), 3-(1H-benzo [d] imidazole-2-yl) phenol (BIP3) and 4-(1H-benzo [d] imidazole-2-yl) phenol (BIP4). The structure of benzimidazoles monomers and polybenzimidazoles (PBI) were confirmed by various spectroscopic techniques. The quantum theoretical calculations of band gap energy values of monomers were done with DFT and are compared with its optical band gap energy values. Fluorescence spectra of these compounds showed maximum emission in blue region. The electrical conductivity of PBIs was measured by four-point probe technique and showed good electrical response on iodine doping and conductivity increases with increase iodine doping time. The differences in conductivities among the three PBIs are in accordance with the charge density on imidazole nitrogens calculated by Huckel method. The high carbines residue (∼40%) at 500 °C in thermo gravimetric analysis shows that the PBIs are having reasonably good thermal stability. Polymers have recorded high dielectric constant at low applied frequency of 50 Hz at 393 K. The I-V characteristics of polybenzimidazoles p-n diodes showed rectifying nature with a typical forward to reverse current in the range -4 to 4 V. The high n values are caused by non homogeneities and effect of series resistance.

  10. Antagonism in the extraction of uranium(VI) by the binary mixture of PC88A and benzimidazole

    International Nuclear Information System (INIS)

    Mukherjee, A.; Kamila, S.; Chakravortty, V.

    1999-01-01

    Extraction studies of uranium(VI) by the binary mixture of PC88A and benzimidazole show an antagonistic behavior in the concentration range 10 -5 -10 -6 M of PC88A and 0.005M of benzimidazole. Antagonism is observed due to the deprotonation of PC88A by benzimidazole forming an adduct resulting in the virtual removal of PC88A from the system. (author)

  11. Crystal structure of a complex of human chymase with its benzimidazole derived inhibitor

    International Nuclear Information System (INIS)

    Matsumoto, Yoshiyuki; Kakuda, Shinji; Koizumi, Masahiro; Mizuno, Tsuyoshi; Muroga, Yumiko; Kawamura, Takashi; Takimoto-Kamimura, Midori

    2013-01-01

    The crystal structure of human chymase complexed with a novel benzimidazole inhibitor, TJK002, was determined at 2.8 Å resolution. The present study shows that the benzimidazole ring of the inhibitor takes the stable stacking interaction with the protonated His57 in the catalytic domain of human chymase. The crystal structure of human chymase complexed with a novel benzimidazole inhibitor, TJK002, was determined at 2.8 Å resolution. The X-ray crystallographic study shows that the benzimidazole inhibitor forms a non-covalent interaction with the catalytic domain of human chymase. The hydrophobic fragment of the inhibitor occupies the S1 pocket. The carboxylic acid group of the inhibitor forms hydrogen bonds with the imidazole N(∊) atom of His57 and/or the O(γ) atom of Ser195 which are members of the catalytic triad. This imidazole ring of His57 induces π–π stacking to the benzene ring of the benzimidazole scaffold as P2 moiety. Fragment molecular orbital calculation of the atomic coordinates by X-ray crystallography shows that this imidazole ring of His57 could be protonated with the carboxyl group of Asp102 or hydroxyl group of Ser195 and the stacking interaction is stabilized. A new drug design strategy is proposed where the stacking to the protonated imidazole of the drug target protein with the benzimidazole scaffold inhibitor causes unpredicted potent inhibitory activity for some enzymes

  12. 5-Bromo-2-aryl benzimidazole derivatives as non-cytotoxic potential dual inhibitors of α-glucosidase and urease enzymes.

    Science.gov (United States)

    Arshad, Tanzila; Khan, Khalid Mohammed; Rasool, Najma; Salar, Uzma; Hussain, Shafqat; Asghar, Humna; Ashraf, Mohammed; Wadood, Abdul; Riaz, Muhammad; Perveen, Shahnaz; Taha, Muhammad; Ismail, Nor Hadiani

    2017-06-01

    On the basis of previous report on promising α-glucosidase inhibitory activity of 5-bromo-2-aryl benzimidazole derivatives, these derivatives were further screened for urease inhibitory and cytotoxicity activity in order to get more potent and non-cytotoxic potential dual inhibitor for the patients suffering from diabetes as well as peptic ulcer. In this study, all compounds showed varying degree of potency in the range of (IC 50 =8.15±0.03-354.67±0.19μM) as compared to standard thiourea (IC 50 =21.25±0.15μM). It is worth mentioning that derivatives 7 (IC 50 =12.07±0.05μM), 8 (IC 50 =10.57±0.12μM), 11 (IC 50 =13.76±0.02μM), 14 (IC 50 =15.70±0.12μM) and 22 (IC 50 =8.15±0.03μM) were found to be more potent inhibitors than standard. All compounds were also evaluated for cytotoxicity towards 3T3 mouse fibroblast cell line and found to be completely non-toxic. Previously benzimidazole 1-25 were also showed α-glucosidase inhibitory potential. In silico studies were performed on the lead molecules i.e.2, 7, 8, 11, 14, and 22, in order to rationalize the binding interaction of compounds with the active site of urease enzyme. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Nanostructured poly(benzimidazole membranes by N-alkylation

    Directory of Open Access Journals (Sweden)

    J. Weber

    2014-01-01

    Full Text Available Modification of poly(benzimidazole (PBI by N-alkylation leads to polymers capable of undergoing microphase separation. Polymers with different amounts of C18 alkyl chains have been prepared. The polymers were analyzed by spectroscopy, thermal analysis, electron microscopy and X-ray scattering. The impact of the amount of alkyl chains on the observed microphase separation was analyzed. Membranes prepared from the polymers do show microphase separation, as evidenced by scattering experiments. While no clear morphology could be derived for the domains in the native state, evidence for the formation of lamellar morphologies upon doping with phosphoric acid is provided. Finally, the proton conductivity of alkyl-modified PBI is compared with that of pure PBI, showing that the introduction of alkyl side chains does not result in significant conductivity changes.

  14. Antituberculosis: Synthesis and Antimycobacterial Activity of Novel Benzimidazole Derivatives

    Directory of Open Access Journals (Sweden)

    Yeong Keng Yoon

    2013-01-01

    Full Text Available A total of seven novel benzimidazoles were synthesized by a 4-step reaction starting from 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The synthesized compounds were screened for their antimycobacterial activity against M. tuberculosis H37Rv (MTB-H37Rv and INH-resistant M. tuberculosis (INHR-MTB strains using agar dilution method. Three of them displayed good activity with MIC of less than 0.2 μM. Compound ethyl 1-(2-(4-(4-(ethoxycarbonyl-2-aminophenylpiperazin-1-ylethyl-2-(4-(5-(4-fluorophenylpyridin-3-ylphenyl-1H-benzo[d]imidazole-5-carboxylate (5g was found to be the most active with MIC of 0.112 μM against MTB-H37Rv and 6.12 μM against INHR-MTB, respectively.

  15. Antibacterial activity of head-to-head bis-benzimidazoles.

    Science.gov (United States)

    Moreira, Joao B; Mann, John; Neidle, Stephen; McHugh, Timothy D; Taylor, Peter W

    2013-10-01

    Symmetric bis-benzimidazole (BBZ) conjugates were profiled for activity against a range of Gram-positive and Gram-negative bacteria. para-Substituted ethoxy, amino and methoxy derivatives displayed potent bacteriostatic activity against meticillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, streptococci and Listeria monocytogenes. Moderate to good activity was also found against mycobacteria; two compounds were strongly active against logarithmic phase and hypoxia-induced latent Mycobacterium tuberculosis. No compound displayed significant activity towards Gram-negative bacteria. Only high concentrations of antibacterial BBZs showed cytotoxic effects towards fibroblasts, and the most active compound was well tolerated by zebrafish embryos. Copyright © 2013 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  16. Seven benzimidazole pesticides combined at sub-threshold levels induce micronuclei in vitro

    Science.gov (United States)

    Ermler, Sibylle; Scholze, Martin; Kortenkamp, Andreas

    2013-01-01

    Benzimidazoles act by disrupting microtubule polymerisation and are capable of inducing the formation of micronuclei. Considering the similarities in their mechanisms of action (inhibition of microtubule assembly by binding to the colchicine-binding site on tubulin monomers), combination effects according to the principles of concentration addition might occur. If so, it is to be expected that several benzimidazoles contribute to micronucleus formation even when each single one is present at or below threshold levels. This would have profound implications for risk assessment, but the idea has never been tested rigorously. To fill this gap, we analysed micronucleus frequencies for seven benzimidazoles, including the fungicide benomyl, its metabolite carbendazim, the anthelmintics albendazole, albendazole oxide, flubendazole, mebendazole and oxibendazole. Thiabendazole was also tested but was inactive. We used the cytochalasin-blocked micronucleus assay with CHO-K1 cells according to OECD guidelines, and employed an automated micronucleus scoring system based on image analysis to establish quantitative concentration–response relationships for the seven active benzimidazoles. Based on this information, we predicted additive combination effects for a mixture of the seven benzimidazoles by using the concepts of concentration addition and independent action. The observed effects of the mixture agreed very well with those predicted by concentration addition. Independent action underestimated the observed combined effects by a large margin. With a mixture that combined all benzimidazoles at their estimated threshold concentrations for micronucleus induction, micronucleus frequencies of ~15.5% were observed, correctly anticipated by concentration addition. On the basis of independent action, this mixture was expected to produce no effects. Our data provide convincing evidence that concentration addition is applicable to combinations of benzimidazoles that form micronuclei

  17. Antiprotozoal activities of benzimidazoles and correlations with beta-tubulin sequence.

    Science.gov (United States)

    Katiyar, S K; Gordon, V R; McLaughlin, G L; Edlind, T D

    1994-01-01

    Benzimidazoles have been widely used since the 1960s as anthelmintic agents in veterinary and human medicine and as antifungal agents in agriculture. More recently, selected benzimidazole derivatives were shown to be active in vitro against two protozoan parasites, Trichomonas vaginalis and Giardia lamblia, and clinical studies with AIDS patients have suggested that microsporidia are susceptible as well. Here, we first present in vitro susceptibility data for T. vaginalis and G. lamblia using an expanded set of benzimidazole derivatives. Both parasites were highly susceptible to four derivatives, including mebendazole, flubendazole, and fenbendazole (50% inhibitory concentrations of 0.005 to 0.16 microgram/ml). These derivatives also had lethal activity that was time dependent: 90% of T. vaginalis cells failed to recover following a 20-h exposure to mebendazole at 0.17 microgram/ml. G. lamblia, but not T. vaginalis, was highly susceptible to five additional derivatives. Next, we examined in vitro activity of benzimidazoles against additional protozoan parasites: little or no activity was observed against Entamoeba histolytica, Leishmania major, and Acanthamoeba polyphaga. Since the microtubule protein beta-tubulin has been identified as the benzimidazole target in helminths and fungi, potential correlations between benzimidazole activity and beta-tubulin sequence were examined. This analysis included partial sequences (residues 108 to 259) from the organisms mentioned above, as well as the microsporidia Encephalitozoon hellem and Encephalitozoon cuniculi and the sporozoan Cryptosporidium parvum. beta-tubulin residues Glu-198 and, in particular, Phe-200 are strong predictors of benzimidazole susceptibility; both are present in Encephalitozoon spp. but absent in C. parvum. PMID:7811023

  18. Synthesis of benzimidazoles by potassium tert-butoxide-promoted intermolecular cyclization reaction of 2-iodoanilines with nitriles.

    Science.gov (United States)

    Xiang, Shi-Kai; Tan, Wen; Zhang, Dong-Xue; Tian, Xian-Li; Feng, Chun; Wang, Bi-Qin; Zhao, Ke-Qing; Hu, Ping; Yang, Hua

    2013-11-14

    The synthesis of benzimidazoles by intermolecular cyclization reaction of 2-iodoanilines with nitriles has been developed. These reactions proceeded without the aid of any transition metals or ligands and just using KOBu(t) as the base. A variety of substituted benzimidazole derivatives can be synthesized by the approach.

  19. Zirconyl (IV Nitrate as Efficient and Reusable Solid Lewis Acid Catalyst for the Synthesis of Benzimidazole Derivatives

    Directory of Open Access Journals (Sweden)

    Pratapsinha B. Gorepatil

    2013-01-01

    Full Text Available The present paper introduces a simple and efficient method for the synthesis of substituted benzimidazoles by heterocyclization of different o-phenylenediamines and substituted aromatic carboxylic acid/aldehyde in the presence of zirconyl nitrate as catalyst in ethanol under reflux, which produced excellent yield of corresponding benzimidazoles in a short reaction time with reusability of catalyst.

  20. Anion exchange membrane based on alkali doped poly(2,5-benzimidazole) for alkaline membrane fuel cell

    CSIR Research Space (South Africa)

    Luo, H

    2010-03-01

    Full Text Available was prepared. The alkali doped poly(2,5-benzimidazole) membrane is a promising candidate as anion exchange membrane for fuel cell application. The alkali doped poly(2,5-benzimidazole) membrane reached an anion conductivity of 2.3×10-2 S cm-1 at room temperature...

  1. Synthesis, crystal structure, spectroscopic characterization, Hirshfeld surface analysis, and DFT calculations of 1,4-dimethyl-2-oxo-pyrimido[1,2-a]benzimidazole hydrate

    Science.gov (United States)

    El Bakri, Youness; Anouar, El Hassane; Ramli, Youssef; Essassi, El Mokhtar; Mague, Joel T.

    2018-01-01

    Imidazopyrimidine derivatives are organic synthesized compounds with a pyrimido[1,2-a]benzimidazole as basic skeleton. They are known for their various biological properties and as an important class of compounds in medicinal chemistry. A new 1,4-dimethyl-2-oxo-pyrimido[1,2-a]benzimidazole hydrate derivative of the tilted group has been synthesized and characterized by spectroscopic techniques NMR and FT-IR; and by a single crystal X-ray diffraction. The X-ray results showed that the tricyclic core of the title compound, C12H11N3O·H2O, is almost planar. The molecules stack along the a-axis direction in head-to- tail fashion through π-stacking interactions involving all three rings. The stacks are tied together by direct Csbnd H⋯O hydrogen bonds and by Osbnd H⋯O, Osbnd N⋯N and Csbnd H⋯O hydrogen bonds with the lattice water. DFT calculations at B3LYP/6-311++G(d,p) in gas phase an polarizable continuum model have been carried out to predict the spectral and geometrical data of the tilted compound. The obtained results showed relatively good correlations between the predicted and experimental data with correlation coefficients higher than 98%.

  2. Process design of high-concentration benzimidazole wastewater treatment based on the molecular structure of contaminants.

    Science.gov (United States)

    Li, Chenru; Qian, Kun; Liu, Qinyao; Zhang, Qianyi; Yao, Chen; Song, Wei; Wang, Yihong

    2018-04-01

    Benzimidazole is an important intermediate in industry and it is usually difficult to be degraded by many treatment technologies. Looking for a highly effective, environment-friendly degradation process for benzimidazole wastewater is of great significance to reduce pollution. Based on the structure of contaminants, the micro-electrolysis (ME) coupled with the Fenton technique was chosen to degrade the industrial benzimidazole wastewater. Special feeding was applied to maintain the suitable hydrogen peroxide (H 2 O 2 ) concentration to produce the hydroxyl radicals (•OH) as much as possible and protect •OH from being quenched by excess H 2 O 2 according to the reaction mechanism. The results showed that this combined technique was highly efficient to decompose benzimidazole compounds. More chemical oxygen demand (COD) could be reduced when flow control was used, compared to the flow not being controlled. The COD removal rate could reach 85.2% at optimal parameters. Then the effluent of this process was combined with the existing biochemical system for further degradation. The studies of Ultraviolet Spectrophotometry, Fourier Transform Infrared Spectroscopy and Liquid Chromatography Mass Spectrometry showed that both 2-(a-Hydroxyethyl) benzimidazole and 2-Acetylbenzimidazole were decomposed to the isopropanolamine and aniline after the ME treatment; then the intermediates were oxidized into oxalic acid after the Fenton reaction.

  3. Evaluation of chromatographic columns packed with semi- and fully porous particles for benzimidazoles separation.

    Science.gov (United States)

    Gonzalo-Lumbreras, Raquel; Sanz-Landaluze, Jon; Cámara, Carmen

    2015-07-01

    The behavior of 15 benzimidazoles, including their main metabolites, using several C18 columns with standard or narrow-bore diameters and different particle size and type were evaluated. These commercial columns were selected because their differences could affect separation of benzimidazoles, and so they can be used as alternative columns. A simple screening method for the analysis of benzimidazole residues and their main metabolites was developed. First, the separation of benzimidazoles was optimized using a Kinetex C18 column; later, analytical performances of other columns using the above optimized conditions were compared and then individually re-optimized. Critical pairs resolution, analysis run time, column type and characteristics, and selectivity were considered for chromatographic columns comparison. Kinetex XB was selected because it provides the shortest analysis time and the best resolution of critical pairs. Using this column, the separation conditions were re-optimized using a factorial design. Separations obtained with the different columns tested can be applied to the analysis of specific benzimidazoles residues or other applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Probing the molecules of the mind

    African Journals Online (AJOL)

    Adele

    2005-01-10

    Jan 10, 2005 ... versa. In this way each strand of DNA is strongly bound through specific ... receptor array, and the behaviour of each cell is orchestrated by which ..... netic mechanisms operative during sleep, in which state cer- tain genes are ...

  5. The inhibition performance of long-chain alkyl-substituted benzimidazole derivatives for corrosion of mild steel in HCl

    International Nuclear Information System (INIS)

    Zhang, Dongqin; Tang, Yongming; Qi, Sijun; Dong, Dawei; Cang, Hui; Lu, Gang

    2016-01-01

    Highlights: • Inhibition performance of long-chain alkyl-substituted benzimidazole. • Benzimidazole segment donating electrons to metal surface. • Non-polar long chain enhancing inhibition by the barrier effect. • Molecular form of DBI more tightly adsorbs on the steel than its protonated form. - Abstract: The corrosion inhibition of a new benzimidazole derivative, 6-(dodecyloxy)-1H-benzo[d]imidazole (DBI), for mild steel in 1 M HCl was investigated in this paper. Computational chemistry was performed to explore the adsorption of DBI on metal surface. Inhibition performance of DBI is attributed to both the direct interaction of benzimidazole segment with iron surface and the barrier effect of the non-polar long chain against aggressive solution. Compared to the protonated form, the molecular form of DBI could more tightly interact with iron surface. These results show that the long-chain alkyl-substituted benzimidazole derivative is of great potential application as corrosion inhibitor.

  6. Molecule nanoweaver

    Science.gov (United States)

    Gerald, II; Rex, E [Brookfield, IL; Klingler, Robert J [Glenview, IL; Rathke, Jerome W [Homer Glen, IL; Diaz, Rocio [Chicago, IL; Vukovic, Lela [Westchester, IL

    2009-03-10

    A method, apparatus, and system for constructing uniform macroscopic films with tailored geometric assemblies of molecules on the nanometer scale. The method, apparatus, and system include providing starting molecules of selected character, applying one or more force fields to the molecules to cause them to order and condense with NMR spectra and images being used to monitor progress in creating the desired geometrical assembly and functionality of molecules that comprise the films.

  7. Polybenzimidazole Membranes Containing Benzimidazole Side Groups for High Temprature Polymer Electrolyte Membrane Fuel Cells

    DEFF Research Database (Denmark)

    Yang, Jingshuai; Li, Xueyuan; Xu, Yizin

    2013-01-01

    Polybenzimidazole (PBI) with a high molecular weight of 69,000 was first synthesized. It was afterwards grafted with benzimidazole pendant groups on the backbones. The acid doped benzimidaozle grafted PBI membranes were investigated and characterized including fuel cell tests at elevated temperat......Polybenzimidazole (PBI) with a high molecular weight of 69,000 was first synthesized. It was afterwards grafted with benzimidazole pendant groups on the backbones. The acid doped benzimidaozle grafted PBI membranes were investigated and characterized including fuel cell tests at elevated...... temperatures without humidification. At an acid doping level of 13.1 mol H3PO4 per average molar repeat unit, the PBI membranes with a benzimidazole grafting degree of 10.6% demonstrated a conductivity of 0.15 S cm-1 and a H2-air fuel cell peak power density of 378 mW cm-2 at 180 oC at ambient pressure without...

  8. Benzimidazoles: an ideal privileged drug scaffold for the design of multitargeted anti-inflammatory ligands.

    Science.gov (United States)

    Kaur, Gaganpreet; Kaur, Maninder; Silakari, Om

    2014-01-01

    The recent research area endeavors to discover ultimate multi-target ligands, an increasingly feasible and attractive alternative to existing mono-targeted drugs for treatment of complex, multi-factorial inflammation process which underlays plethora of debilitated health conditions. In order to improvise this option, exploration of relevant chemical core scaffold will be an utmost need. Privileged benzimidazole scaffold being historically versatile structural motif could offer a viable starting point in the search for novel multi-target ligands against multi-factorial inflammation process since, when appropriately substituted, it can selectively modulate diverse receptors, pathways and enzymes associated with the pathogenesis of inflammation. Despite this remarkable capability, the multi-target capacity of the benzimidazole scaffold remains largely unexploited. With this in focus, the present review article attempts to provide synopsis of published research to exemplify the valuable use of benzimidazole nucleus and focus on their suitability as starting scaffold to develop multi-targeted anti-inflammatory ligands.

  9. Organizing and addressing magnetic molecules.

    Science.gov (United States)

    Gatteschi, Dante; Cornia, Andrea; Mannini, Matteo; Sessoli, Roberta

    2009-04-20

    Magnetic molecules ranging from simple organic radicals to single-molecule magnets (SMMs) are intensively investigated for their potential applications in molecule-based information storage and processing. The goal of this Article is to review recent achievements in the organization of magnetic molecules on surfaces and in their individual probing and manipulation. We stress that the inherent fragility and redox sensitivity of most SMM complexes, combined with the noninnocent role played by the substrate, ask for a careful evaluation of the structural and electronic properties of deposited molecules going beyond routine methods for surface analysis. Detailed magnetic information can be directly obtained using X-ray magnetic circular dichroism or newly emerging scanning probe techniques with magnetic detection capabilities.

  10. Synthesis, electronic properties, antioxidant and antibacterial activity of some new benzimidazoles.

    Science.gov (United States)

    Mavrova, Anelia Ts; Yancheva, Denitsa; Anastassova, Neda; Anichina, Kamelya; Zvezdanovic, Jelena; Djordjevic, Aleksandra; Markovic, Dejan; Smelcerovic, Andrija

    2015-10-01

    Two groups of benzimidazole derivatives were synthesized using as precursors 5(6)-substituted 2-mercapto-benzimidazol-thiols and their antioxidant activity was investigated using TBA-MDA test. In the group of 1,3-disubstituted-benzimidazol-2-imines the highest lipid peroxidation inhibition effect 74.04% (IC₅₀=141.89 μg/mL) revealed ethyl [3-(2-ethoxy-2-oxoethyl)-2-imino-5-benzoyl-2,3-dihydro-1H-benzimdazol-1-yl]acetate 12 while in the group of 2-substituted-1,3-thiazolo[3,2-a]benzimidazolones the highest inhibition effect showed 2-(4-fluorobenzylidene)-7-(phenylcarbonyl)[1,3]thiazolo[3,2-a]benzimidazol-3(2H)-one 17 90.76% (IC₅₀=53.70 μg/mL). In order to estimate the capability of the studied benzimidazoles to act as radical scavengers the structure of the most active derivative within the both subseries was optimized at B3LYP/6-311++G(∗∗) level and the respective bond dissociation enthalpies were calculated. The appropriate models for the HAT and SET-mechanism of the antioxidant activity were proposed. The antibacterial activity of the compounds was evaluated against two Gram-positive bacteria (Bacillus subtilis ATCC 6633 and Staphylococcus aureus ATCC 6538) and three Gram-negative bacteria (Escherichia coli ATCC 8739, Pseudomonas aeruginosa ATCC 9027 and Salmonella abony NCTC 6017). 1,3-Diphenylpropyl-5-methyl-1,3-dihydro-2H-benzimidazol-2-imine 14 exhibited significant activity against B. subtilis, S. aureus, S. abony and E. coli (with MIC values of 0.125, 0.016, 0.50 and 0.50mg/mL, respectively). The group of thiazolobenzimidazolones did not reveal antibacterial activity against the tested strains. Copyright © 2015. Published by Elsevier Ltd.

  11. DTPA: Bis benzimidazole as multi model imaging agent

    International Nuclear Information System (INIS)

    Srivastava, Vikas; Tiwari, A.K.; Sharma, H.; Sharma, R.; Mishra, A.K.

    2010-01-01

    Full text: The DTPA bis benzimidazole analogue has been tested for radiopharmaceutical efficacy. The radiolabelling was found more then 98% after 8 hrs and blood kinetics was fast. The compound was also tested for optical imaging agent. The Eu 3+ ion has an absorption band in the visible spectrum (578-582 nm) whose wavelength is very sensitive to even small changes in the coordination environment. Although the intensity of this 7F0 → 5D0 transition is low, the bands are relatively narrow, which allows distinguishing different coordination states of the metal. For Eu 3+ complexes which have two differently hydrated forms in aqueous solution, one observes two absorption bands belonging to the two species. High-resolution UV-visible spectra were recorded in aqueous solutions which show a temperature invariant absorption with two distinct, temperature-dependent absorption bands. The intensity ratio of these two bands changes with temperature: the band at shorter wavelengths is decreasing very slightly, while that at longer wavelengths is increasing with the temperature. The ratio of the integrals of the two bands is related to the equilibrium constant, and its temperature dependence yields the reaction enthalpy and entropy

  12. Novel structural hybrids of pyrazolobenzothiazines with benzimidazoles as cholinesterase inhibitors.

    Science.gov (United States)

    Aslam, Sana; Zaib, Sumera; Ahmad, Matloob; Gardiner, John M; Ahmad, Aqeel; Hameed, Abdul; Furtmann, Norbert; Gütschow, Michael; Bajorath, Jürgen; Iqbal, Jamshed

    2014-05-06

    Two series of novel pyrazolobenzothiazine-based hybrid compounds were efficiently synthesized starting from saccharin sodium salt. Pyrazolo[4,3-c][1,2]benzothiazine scaffolds were N-arylated by using p-fluorobenzaldehyde, followed by the incorporation of a benzimidazole or similar ring systems by treatment with arylenediamines. These phenylene-connected hybrid compounds were investigated as potential inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Compounds 12d and 12k were the most potent AChE inhibitors with IC50 values of 11 and 13 nM, respectively, while 6j (IC50 = 17 nM) proved to be the most active inhibitor against BuChE with remarkable selectivity for BuChE over AChE. Molecular docking studies were also performed on human AChE and BuChE to suggest possible binding modes in which the inhibitor's extended structure is accommodated along the active site gorge of both enzymes. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  13. 99mTc labeled benzimidazole for detecting brain application

    International Nuclear Information System (INIS)

    Kumar, Nitin; Srivastava, V.; Tiwari, A.K.; Mishra, A.K.

    2010-01-01

    Full text: The synthesis and structure-activity relationship of a new class of Benzimidazole/Benzthiazole derivatives with low-nanomolar affinity for the Dopaminergic catachol and high selectivity versus the MAO receptor were found. Based on their chemical structure, four new derivatives which contain atoms to afford future labeling with PET isotopes, were synthesized and evaluated for enzyme activity. All the compound were tested for radiopharmaceutical efficacy. The % radiolabeling efficacy were found more than 95% after 24 hrs. The blood kinetics were found fast in nature which shows that this drug can be utilized for such application in which drug will go in longer time. The % reach in brain were found 3 to 5% which confirms that it can be utilized as brain imaging agent. The Enzyme kinetics of this compound has been studied spectrophotometrically at 25.0 deg C and at constant ionic strength of 0.10 mol dm-3. The products were identified by LCESI-MS technique and other spectral studies

  14. Discovery of a novel series of benzimidazole derivatives as diacylglycerol acyltransferase inhibitors.

    Science.gov (United States)

    Lee, Kyeong; Goo, Ja-Il; Jung, Hwa Young; Kim, Minkyoung; Boovanahalli, Shanthaveerappa K; Park, Hye Ran; Kim, Mun-Ock; Kim, Dong-Hyun; Lee, Hyun Sun; Choi, Yongseok

    2012-12-15

    A novel series of benzimidazole derivatives was prepared and evaluated for their diacylglycerol acyltransferase (DGAT) inhibitory activity using microsome from rat liver. Among the newly synthesized compounds, furfurylamine containing benzimidazole carboxamide 10j showed the most potent DGAT inhibitory effect (IC(50)=4.4 μM) and inhibited triglyceride formation in HepG2 cells. Furthermore, compound 10j reduced body weight gain of Institute of Cancer Research mice on a high-fat diet and decreased levels of total triglyceride, total cholesterol, and LDL-cholesterol in the blood accompanied with a significant increase in HDL-cholesterol level. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Regioselective Synthesis of Some Pyrazole Scaffolds Attached to Benzothiazole and Benzimidazole Moieties

    Directory of Open Access Journals (Sweden)

    Nabila A. Kheder

    2014-01-01

    Full Text Available Condensation of 2-(benzothiazol-2-ylacetonitrile (1 or 2-(1-methyl-1H-benzimidazol-2-ylacetonitrile (2 with thiophene-2-carbaldehyde afforded the corresponding acrylonitrile derivatives 3 or 4, respectively. The 1,3-dipolar cycloaddition reaction of the acrylonitrile 3 or 4 with nitrile-imine 6 gave novel pyrazole derivatives pendant to benzothiazole and benzimidazole. The pyrazoline derivative 7 was converted into the corresponding pyrazole derivative 11 via thermal elimination of hydrogen cyanide upon heating in sodium ethoxide solution. The structures of the synthesized products were confirmed by IR, 1H NMR, and mass spectral techniques.

  16. C2-Selective Branched Alkylation of Benzimidazoles by Rhodium(I)-Catalyzed C-H Activation.

    Science.gov (United States)

    Tran, Gaël; Confair, Danielle; Hesp, Kevin D; Mascitti, Vincent; Ellman, Jonathan A

    2017-09-01

    Herein, we report a Rh(I)/bisphosphine/K 3 PO 4 catalytic system allowing for the first time the selective branched C-H alkylation of benzimidazoles with Michael acceptors. Branched alkylation with N,N-dimethyl acrylamide was successfully applied to the alkylation of a broad range of benzimidazoles incorporating a variety of N-substituents and with both electron-rich and -poor functionality displayed at different sites of the arene. Moreover, the introduction of a quaternary carbon was achieved by alkylation with ethyl methacrylate. The method was also shown to be applicable to the C2-selective branched alkylation of azabenzimidazoles.

  17. Benzimidazole and its derivatives as corrosion inhibitors for mild steel in 1M HCl solution

    International Nuclear Information System (INIS)

    Aljourani, J.; Raeissi, K.; Golozar, M.A.

    2009-01-01

    In this paper, the inhibition ability of benzimidazole and its derivatives against the corrosion of mild steel in 1M HCl solution was studied. The change of impedance parameters observed by variation of inhibitors concentration within the range of 50-250 ppm was an indication of their adsorption. The thermodynamic adsorption parameters proposed that these inhibitors retard both cathodic and anodic processes through physical adsorption and blocking the active corrosion sites. The adsorption of these compounds obeyed the Langmuir's adsorption isotherm. The inhibition efficiency was increased with inhibitor concentration in the order of 2-mercaptobenzimidazole > 2-methylbenzimidazole > benzimidazole, which is in accordance with the variation of apparent activation energy of corrosion.

  18. Ball Milling Assisted Solvent and Catalyst Free Synthesis of Benzimidazoles and Their Derivatives.

    Science.gov (United States)

    El-Sayed, Taghreed H; Aboelnaga, Asmaa; Hagar, Mohamed

    2016-08-24

    Benzoic acid and o-phenylenediamine efficiently reacted under the green solvent-free Ball Milling method. Several reaction parameters were investigated such as rotation frequency; milling balls weight and milling time. The optimum reaction condition was milling with 56.6 g weight of balls at 20 Hz frequency for one hour milling time. The study was extended for synthesis of a series of benzimidazol-2-one or benzimidazol-2-thione using different aldehydes; carboxylic acids; urea; thiourea or ammonium thiocyanate with o-phenylenediamine. Moreover; the alkylation of benzimidazolone or benzimidazolthione using ethyl chloroacetate was also studied.

  19. The Influence of Substituents on the Tautomerism of Symmetrically Substituted 2,2'-Bis-benzimidazoles

    Directory of Open Access Journals (Sweden)

    Dall'Oglio Evandro

    2002-01-01

    Full Text Available The tautomerism of five symmetrically substituted 2,2'-bis-benzimidazoles [5(6,5'(6'-tetramethyl- (1; 5(6,5'(6'-dimethyl-(2; 5(6,5'(6'-dichloro- (3; 5(6,5'(6'-dimethoxy- (4 and 4(7,4'(7'-dimethyl-2,2'-bis-benzimidazole (5], was studied by means of ¹H NMR spectroscopy at variable temperatures, and the influence of the substituents on the energy barriers for tautomeric interconversion was interpreted with the aid of theoretical calculations.

  20. An Efficient Synthesis of 2-Substituted Benzimidazoles via Photocatalytic Condensation of o-Phenylenediamines and Aldehydes.

    Science.gov (United States)

    Kovvuri, Jeshma; Nagaraju, Burri; Kamal, Ahmed; Srivastava, Ajay K

    2016-10-10

    A photocatalytic method has been developed for the efficient synthesis of functionalized benzimidazoles. This protocol involves photocatalytic condensation of o-phenylenediamines with various aldehydes using the Rose Bengal as photocatalyst. The method was found to be general and was successfully employed for accessing pharmaceutically important benzimidazoles by the condensation of aromatic, heteroaromatic and aliphatic aldehydes with o-phenylenediamines, in good-to-excellent yields. Notably, the method was found to be effective for the condensation of less reactive heterocyclic aldehydes with o-phenylenediamines.

  1. Coordination compounds of metals with imidazoles and benzimidazoles. [Metals: V, Th, Mo, Cd, rare earths, etc

    Energy Technology Data Exchange (ETDEWEB)

    Novikova, G A; Molodkin, A K; Kukalenko, S S

    1988-12-01

    Methods of preparation, composition and structure of UO/sub 2//sup 2+/, Th/sup 4+/, Mo/sup 3+/, Cd/sup 2+/, Ln/sup 3+/ metal ion complexes with imidazoles and benzimidazoles are considered in reviews of native and foreign literature of up to 1985. Complexes are customarily prepared by direct interaction of ligands with inorganic salts in different organic solvents. Complex composition is defined by the nature of complexing metal and inorganic salt anion, ligand volume and basicity, as well as solvent characteristics. Effect of R substituent in imidazole and benzimidazole side chain on composition of coordination compounds is considered.

  2. In vitro activity of wALADin benzimidazoles against different life cycle stages of Plasmodium parasites.

    Science.gov (United States)

    Lentz, Christian S; Sattler, Julia M; Fendler, Martina; Gottwalt, Simon; Halls, Victoria S; Strassel, Silke; Arriens, Sandra; Hannam, Jeffrey S; Specht, Sabine; Famulok, Michael; Mueller, Ann-Kristin; Hoerauf, Achim; Pfarr, Kenneth M

    2015-01-01

    wALADin1 benzimidazoles are specific inhibitors of δ-aminolevulinic acid dehydratase from Wolbachia endobacteria of filarial nematodes. We report that wALADin1 and two derivatives killed blood stage Plasmodium falciparum in vitro (50% inhibitory concentrations, 39, 7.7, and 12.8 μM, respectively). One of these derivatives inhibited gliding motility of Plasmodium berghei ANKA infectious sporozoites with nanomolar affinity and blocked invasion into hepatocytes but did not affect intrahepatocytic replication. Hence, wALADin1 benzimidazoles are tools to study gliding motility and potential antiplasmodial drug candidates. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Lead optimization of 2-(piperidin-3-yl)-1H-benzimidazoles: identification of 2-morpholin- and 2-thiomorpholin-2-yl-1H-benzimidazoles as selective and CNS penetrating H₁-antihistamines for insomnia.

    Science.gov (United States)

    Ravula, Satheesh Babu; Yu, Jinghua; Tran, Joe A; Arellano, Melissa; Tucci, Fabio C; Moree, Wilna J; Li, Bin-Feng; Petroski, Robert E; Wen, Jianyun; Malany, Siobhan; Hoare, Samuel R J; Madan, Ajay; Crowe, Paul D; Beaton, Graham

    2012-01-01

    The structure-activity relationships of 2-(piperidin-3-yl)-1H-benzimidazoles, 2-morpholine and 2-thiomorpholin-2-yl-1H-benzimidazoles are described. In the lead optimization process, the pK(a) and/or logP of benzimidazole analogs were reduced either by attachment of polar substituents to the piperidine nitrogen or incorporation of heteroatoms into the piperidine heterocycle. Compounds 9a and 9b in the morpholine series and 10g in the thiomorpholine series demonstrated improved selectivity and CNS profiles compared to lead compound 2 and these are potential candidates for evaluation as sedative hypnotics. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Bis[2-(2-aminoethyl-1H-benzimidazole-κ2N2,N3](nitrato-κ2O,O′cobalt(II chloride trihydrate

    Directory of Open Access Journals (Sweden)

    Jing Zhao

    2012-06-01

    Full Text Available In the title compound, [Co(NO3(C9H11N32]Cl·3H2O, the CoII atom is coordinated by four N atoms from two chelating 2-(2-aminoethyl-1H-benzimidazole ligands and two O atoms from one nitrate anion in a distorted octahedral coordination environment. In the crystal, N—H...Cl, N—H...O, O—H...Cl and O—H...O hydrogen bonds link the complex cations, chloride anions and solvent water molecules into a three-dimensional network. π–π interactions between the imidazole and benzene rings and between the benzene rings are observed [centroid–centroid distances = 3.903 (3, 3.720 (3, 3.774 (3 and 3.926 (3 Å].

  5. Synthesis, crystal structure determination and antiproliferative activity of novel 2-amino-4-aryl-4,10-dihydro[1,3,5]triazino[1,2- a]benzimidazoles

    Science.gov (United States)

    Hranjec, Marijana; Pavlović, Gordana; Karminski-Zamola, Grace

    2012-01-01

    This manuscript describes the synthesis of novel 2-amino-4-aryl-4,10-dihydro-[1,3,5]triazino[1,2- a]benzimidazoles as hydrochloride salts 4a-n and 5b which were prepared in the reaction of cyclocondensation between 2-guanidinobenzimidazole and versatile heteroaromatic aldehydes. Structures of all prepared compounds have been studied by using 1H and 13C NMR, IR and UV/Vis spectroscopy. The crystal and molecular structure of 4f was determined by X-ray diffraction on single crystals. The molecule of 2-amino-4-(4'-methylphenyl)-4,10-dihydro[1,3,5]triazino[1,2- a]benzimidazole hydrochloride 4f (C 16H 16N 5+·Cl -) exists in the solid state in one of the possible tautomeric forms, being protonated at the one of the nitrogen atoms of the 1,4-dihydrotriazine ring. The molecule is highly delocalized within the 4,10-dihydro[1,3,5]triazino[1,2- a]benzimidazole moiety with the highest deviation from the plane for the methine carbon atom and the protonated nitrogen atom of the 1,4-dihydrotriazine ring. The cations are joined via N-H⋯N hydrogen bonds into R22(8) centrosymmetric dimers. Cation dimers are further connected with Cl - ions via N-H⋯Cl and C-H⋯Cl hydrogen bonds into 2D chains spreading along the b axis. The obtained single-crystal X-ray structure determination unequivocally confirms tautomeric form of the compound present in the solid-state and can represent tantative pattern for other prepared compounds. All prepared compounds were tested on their antiproliferative activity in vitro on several human cancer cell lines. Compound 4m was the most active one (IC 50 ≈ 20 μM), while compounds 4d, 4f, 4k, 4l4m showed moderate, but non-selective, antiproliferative activity with IC 50 25-60 μM.

  6. 2-(1H-Benzimidazol-2-yl-4,5,6,7-tetrahydro-2H-indazol-3-ol, a Benzimidazole Derivative, Inhibits T Cell Proliferation Involving H+/K+-ATPase Inhibition

    Directory of Open Access Journals (Sweden)

    Jin Liu

    2014-10-01

    Full Text Available In this study, a benzimidazole derivative named BMT-1 is revealed as a potential immunomodulatory agent. BMT-1 inhibits the activity of H+/K+-ATPases from anti-CD3/CD28 activated T cells. Furthermore, inhibition the H+/K+-ATPases by use of BMT-1 should lead to intracellular acidification, inhibiting T cell proliferation. To explore this possibility, the effect of BMT-1 on intracellular pH changes was examined by using BCECF as a pH-dependent fluorescent dye. Interestingly, increases in the pHi were observed in activated T cells, and T cells treated with BMT-1 showed a more acidic intracellular pH. Finally, BMT-1 targeted the H+/K+-ATPases and inhibited the proliferative response of anti-CD3/CD28-stimulated T cells. A cell cycle analysis indicated that BMT-1 arrested the cell cycle progression of activated T cells from the G1 to the S phase without affecting CD25 expression or interleukin-2 (IL-2 production; treating IL-2-dependent PBMCs with BMT-1 also led to the inhibition of cell proliferation. Taken together, these findings demonstrate that BMT-1 inhibits the proliferation of T cells by interfering with H+/K+-ATPases and down-regulating intracellular pHi. This molecule may be an interesting lead compound for the development of new immunomodulatory agents.

  7. Metabolic conversion of methyl benzimidazol 2 yl carbamate (MBC) in Aspergillus nidulans

    NARCIS (Netherlands)

    Davidse, L.C.

    1976-01-01

    Methyl benzimidazol 2 yl carbamate was metabolized by Aspergillus nidulans mycelium to two metabolites, one of which was identified as methyl 5 hydroxybenzimidazol 2 yl carbamate. This compound was further converted to a second metabolite which was not identified. Conversion rate was highest when

  8. Pressure injection of methyl 2-benzimidazole carbamate hydrochloride solution as a control for Dutch elm disease

    Science.gov (United States)

    Garold F. Gregory; Thomas W. Jones

    1973-01-01

    A preliminary evaluation of the effectiveness of injecting methyl 2-benzimidazole carbamate hydrochloride solution into elms for prevention or cure of Dutch elm disease is reported. Symptom development was diminished or prevented in elms injected with fungicide before inoculation. Symptom development was arrested in all crown-inoculated diseased trees injected with the...

  9. Triphenylamine based benzimidazole and benzothiazole: Synthesis and applications in fluorescent chemosensors and laser dyes

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yang [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Li, Bin, E-mail: libinteacher@163.com [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China); Zhang, Liming; Guan, Yunlong [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China)

    2014-01-15

    Triphenylamine based fluorescent dyes TPA-benzimidazole and TPA-benzothiazole have been designed and synthesized. The TPA-benzimidazole chemosensor was tested for a number of metal ions and found to exhibit binding affinity for Fe{sup 3+} and Hg{sup 2+} in acetonitrile, and the fluorescence quenching was achieved through a PET process. The appearance of an isosbestic point in absorption titrations and Job's plot analysis supported 1:1 stoichiometries for Fe{sup 3+} and Hg{sup 2+} ions. Laser experiments showed that under transversal pumping with a Q-switched Nd:YAG (355 nm) laser in toluene, TPA-benzothiazole exhibits efficient and stable amplified spontaneous emissions (ASE) at 436 nm. -- Highlights: • Triphenylamine based fluorescent dyes TPA-benzimidazole and TPA-benzothiazole have been designed and synthesized. • The TPA-benzimidazole exhibits binding affinity for Fe{sup 3+} and Hg{sup 2+} in acetonitrile and the fluorescence quenching was achieved through a PET process. • Under transversal pumping at 355 nm in toluene, TPA-benzothiazole exhibits efficient and stable amplified spontaneous emissions (ASE) in 436 nm.

  10. Potassium hydroxide/dimethyl sulfoxide promoted intramolecular cyclization for the synthesis of benzimidazol-2-ones.

    Science.gov (United States)

    Beyer, Astrid; Reucher, Christine M M; Bolm, Carsten

    2011-06-03

    A new protocol for intramolecular N-arylations of ureas to form benzimidazol-2-ones has been developed. The cyclization reaction occurs in the presence of KOH and DMSO at close to ambient temperature. Under these conditions the yields are high and a wide range of functional groups are tolerated.

  11. Novel fluorinated benzimidazole-based scaffolds and their anticancer activity in vitro

    Czech Academy of Sciences Publication Activity Database

    Bhambra, A.S.; Edgar, M.; Elsegood, M.R.J.; Horsburgh, L.; Kryštof, Vladimír; Lucas, P.D.; Mojally, M.; Teat, S. J.; Warwick, T.G.; Weaver, G.W.; Zeinali, F.

    2016-01-01

    Roč. 188, AUG (2016), s. 99-109 ISSN 0022-1139 R&D Projects: GA ČR(CZ) GA15-15264S Institutional support: RVO:61389030 Keywords : Anticancer activity * Benzimidazole * C-F activation Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.101, year: 2016

  12. Aminosilanes derived from 1H-benzimidazole-2(3H)-thione

    Energy Technology Data Exchange (ETDEWEB)

    Palomo-Molina, Juliana [Facultad de Ciencias Químicas, Universidad de Colima, Carretera Coquimatlán-Colima, Coquimatlán Colima 28400 (Mexico); García-Báez, Efrén V. [Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional, Avenida Acueducto s/n, Barrio La Laguna Ticomán, México DF 07340 (Mexico); Contreras, Rosalinda [Departamento de Química, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, México DF 07000 (Mexico); Barrio La Laguna Ticomán, México DF 07340 (Mexico); Pineda-Urbina, Kayim; Ramos-Organillo, Angel, E-mail: aaramos@ucol.mx [Facultad de Ciencias Químicas, Universidad de Colima, Carretera Coquimatlán-Colima, Coquimatlán Colima 28400 (Mexico)

    2015-08-12

    In two trimethylsilyl-substituted 1H-benzimidazole-2(3H)-thiones, noncovalent C—H⋯π interactions between the centroid of the benzmidazole system and the SiMe{sub 3} groups form helicoidal arrangements in one, and dimerization results in the formation of R{sub s} {sup 2}(8) rings via N—H⋯S interactions, along with parallel π–π interactions between imidazole and benzene rings, in the second compound. Two new molecular structures, namely 1,3-bis(trimethylsilyl)-1H-benzimidazole-2(3H)-thione, C{sub 13}H{sub 22}N{sub 2}SSi{sub 2}, (2), and 1-trimethylsilyl-1H-benzimidazole-2(3H)-thione, C{sub 10}H{sub 14}N{sub 2}SSi, (3), are reported. Both systems were derived from 1H-benzimidazole-2(3H)-thione. Noncovalent C—H⋯π interactions between the centroid of the benzmidazole system and the SiMe{sub 3} groups form helicoidal arrangements in (2). Dimerization of (3) results in the formation of R{sub 2}{sup 2}(8) rings via N—H⋯S interactions, along with parallel π–π interactions between imidazole and benzene rings.

  13. Silica Sulfuric Acid: An Eco-Friendly and Reusable Catalyst for Synthesis of Benzimidazole Derivatives

    Directory of Open Access Journals (Sweden)

    Bahareh Sadeghi

    2013-01-01

    Full Text Available Silica sulfuric acid (SiO2-OSO3H as an eco-friendly, readily available, and reusable catalyst is applied to benzimidazole derivatives synthesis under reflux in ethanol. The procedure is very simple and the products are isolated with an easy workup in good-to-excellent yields.

  14. Aminosilanes derived from 1H-benzimidazole-2(3H)-thione

    International Nuclear Information System (INIS)

    Palomo-Molina, Juliana; García-Báez, Efrén V.; Contreras, Rosalinda; Pineda-Urbina, Kayim; Ramos-Organillo, Angel

    2015-01-01

    In two trimethylsilyl-substituted 1H-benzimidazole-2(3H)-thiones, noncovalent C—H⋯π interactions between the centroid of the benzmidazole system and the SiMe 3 groups form helicoidal arrangements in one, and dimerization results in the formation of R s 2 (8) rings via N—H⋯S interactions, along with parallel π–π interactions between imidazole and benzene rings, in the second compound. Two new molecular structures, namely 1,3-bis(trimethylsilyl)-1H-benzimidazole-2(3H)-thione, C 13 H 22 N 2 SSi 2 , (2), and 1-trimethylsilyl-1H-benzimidazole-2(3H)-thione, C 10 H 14 N 2 SSi, (3), are reported. Both systems were derived from 1H-benzimidazole-2(3H)-thione. Noncovalent C—H⋯π interactions between the centroid of the benzmidazole system and the SiMe 3 groups form helicoidal arrangements in (2). Dimerization of (3) results in the formation of R 2 2 (8) rings via N—H⋯S interactions, along with parallel π–π interactions between imidazole and benzene rings

  15. Metal-containing Complexes of Lactams, Imidazoles, and Benzimidazoles and Their Biological Activity

    Science.gov (United States)

    Kukalenko, S. S.; Bovykin, B. A.; Shestakova, S. I.; Omel'chenko, A. M.

    1985-07-01

    The results of the latest investigations of the problem of the synthesis of metal-containing complexes of lactams, imidazoles, and benzimidazoles, their structure, and their stability in solutions are surveyed. Some data on their biological activity (pesticide and pharmacological) and the mechanism of their physiological action are presented. The bibliography includes 190 references.

  16. Metal-free TEMPO-promoted C(sp³)-H amination to afford multisubstituted benzimidazoles.

    Science.gov (United States)

    Xue, Ding; Long, Ya-Qiu

    2014-05-16

    An efficient TEMPO-air/cat. TEMPO-O2 oxidative protocol was developed to synthesize multisubstituted or fused tetracyclic benzimidazoles via a metal-free oxidative C-N coupling between the sp(3) C-H and free N-H of readily available N(1)-benzyl/alkyl-1,2-phenylenediamines.

  17. Antihelminthic benzimidazoles are novel HIF activators that prevent oxidative neuronal death via binding to tubulin.

    Science.gov (United States)

    Aleyasin, Hossein; Karuppagounder, Saravanan S; Kumar, Amit; Sleiman, Sama; Basso, Manuela; Ma, Thong; Siddiq, Ambreena; Chinta, Shankar J; Brochier, Camille; Langley, Brett; Haskew-Layton, Renee; Bane, Susan L; Riggins, Gregory J; Gazaryan, Irina; Starkov, Anatoly A; Andersen, Julie K; Ratan, Rajiv R

    2015-01-10

    Pharmacological activation of the adaptive response to hypoxia is a therapeutic strategy of growing interest for neurological conditions, including stroke, Huntington's disease, and Parkinson's disease. We screened a drug library with known safety in humans using a hippocampal neuroblast line expressing a reporter of hypoxia-inducible factor (HIF)-dependent transcription. Our screen identified more than 40 compounds with the ability to induce hypoxia response element-driven luciferase activity as well or better than deferoxamine, a canonical activator of hypoxic adaptation. Among the chemical entities identified, the antihelminthic benzimidazoles represented one pharmacophore that appeared multiple times in our screen. Secondary assays confirmed that antihelminthics stabilized the transcriptional activator HIF-1α and induced expression of a known HIF target gene, p21(cip1/waf1), in post-mitotic cortical neurons. The on-target effect of these agents in stimulating hypoxic signaling was binding to free tubulin. Moreover, antihelminthic benzimidazoles also abrogated oxidative stress-induced death in vitro, and this on-target effect also involves binding to free tubulin. These studies demonstrate that tubulin-binding drugs can activate a component of the hypoxic adaptive response, specifically the stabilization of HIF-1α and its downstream targets. Tubulin-binding drugs, including antihelminthic benzimidazoles, also abrogate oxidative neuronal death in primary neurons. Given their safety in humans and known ability to penetrate into the central nervous system, antihelminthic benzimidazoles may be considered viable candidates for treating diseases associated with oxidative neuronal death, including stroke.

  18. Benzimidazoles and benzoxazoles via the nucleophilic addition of anilines to nitroalkanes.

    Science.gov (United States)

    Aksenov, Alexander V; Smirnov, Alexander N; Aksenov, Nicolai A; Bijieva, Asiyat S; Aksenova, Inna V; Rubin, Michael

    2015-04-14

    PPA-induced umpolung triggers efficient nucleophilic addition of unactivated anilines to nitroalkanes to produce N-hydroxyimidamides. The latter undergo sequential acid-promoted cyclocondensation with ortho-OH or ortho-NHR moieties to afford benzoxazoles and benzimidazoles, respectively.

  19. Polyethylene glycol (PEG-400: An efficient medium for the synthesis of 1,2-disubstituted benzimidazoles

    Directory of Open Access Journals (Sweden)

    Raja Sekhar Mekala

    2015-12-01

    Full Text Available Polyethylene glycol (PEG-400 was found to be an inexpensive, non-toxic, and effective medium for the one-pot synthesis of 1,2-disubstituted benzimidazoles in excellent yields. Eco-friendliness, low cost, high yields, and recyclability of the PEG-400 are the important features of this protocol.

  20. Synthesis and study of rhenium (5) complexes with benzimidazole and rubeanic acid

    International Nuclear Information System (INIS)

    Basitova, S.M.; Yurina, R.D.; Kotegov, K.V.; Amindzhanov, A.A.

    1986-01-01

    Mixed rhenium (5) oxohalide complex compounds with benzimidazole and rubeanic acid are synthesized. Composition of the compounds obtained is established by IR spectroscpy thermal and chemical analyses. It is shown that rhenium (5) chloride compound stability to pyrolysis is rather lower than that of the corresponding bromide derivatives

  1. Triphenylamine based benzimidazole and benzothiazole: Synthesis and applications in fluorescent chemosensors and laser dyes

    International Nuclear Information System (INIS)

    Yang, Yang; Li, Bin; Zhang, Liming; Guan, Yunlong

    2014-01-01

    Triphenylamine based fluorescent dyes TPA-benzimidazole and TPA-benzothiazole have been designed and synthesized. The TPA-benzimidazole chemosensor was tested for a number of metal ions and found to exhibit binding affinity for Fe 3+ and Hg 2+ in acetonitrile, and the fluorescence quenching was achieved through a PET process. The appearance of an isosbestic point in absorption titrations and Job's plot analysis supported 1:1 stoichiometries for Fe 3+ and Hg 2+ ions. Laser experiments showed that under transversal pumping with a Q-switched Nd:YAG (355 nm) laser in toluene, TPA-benzothiazole exhibits efficient and stable amplified spontaneous emissions (ASE) at 436 nm. -- Highlights: • Triphenylamine based fluorescent dyes TPA-benzimidazole and TPA-benzothiazole have been designed and synthesized. • The TPA-benzimidazole exhibits binding affinity for Fe 3+ and Hg 2+ in acetonitrile and the fluorescence quenching was achieved through a PET process. • Under transversal pumping at 355 nm in toluene, TPA-benzothiazole exhibits efficient and stable amplified spontaneous emissions (ASE) in 436 nm

  2. Oxovanadium(IV) complexes with tridentate dibasic schiff base ligands and 2-(2'-pyridyl) benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, R N; Chakravortty, V; Dash, K C [Utkal Univ., Bhubaneswar (India). Dept. of Chemistry

    1991-05-01

    The present work deals with the monomeric, six-coordinated mixed-ligand complexes of oxovanadium(IV) with dibasic tridentate schiff base ligands(ONO donor set) and the bidentate chelating ligand 2-(2'-pyridyl)benzimidazole (PBH) containing N{sub 2} donor set. (author). 1 tab., 22 refs.

  3. Synthesis and study of rhenium (5) complexes with benzimidazole and rubeanic acid

    Energy Technology Data Exchange (ETDEWEB)

    Basitova, S M; Yurina, R D; Kotegov, K V; Amindzhanov, A A

    1986-01-01

    Mixed rhenium (5) oxohalide complex compounds with benzimidazole and rubeanic acid are synthesized. Composition of the compounds obtained is established by IR spectroscpy thermal and chemical analyses. It is shown that rhenium (5) chloride compound stability to pyrolysis is rather lower than that of the corresponding bromide derivatives.

  4. Resistance to benzimidazoles and levamisole in nematode parasites of sheep in Nyandarua district of Kenya

    DEFF Research Database (Denmark)

    Maingi, N.; Bjørn, H.; Gichohi, V.M.

    1998-01-01

    The occurrence of anthelmintic resistance on 25 sheep farms in the Nyandarua District of Kenya was investigated, using the faecal egg count reduction test (FECRT), the egg hatch assay (EHA) and a larval development assay (LDA). In the FECRT, resistance to both benzimidazoles (BZs) and levamisole...

  5. Sulfonated copolyimide membranes derived from a novel diamine monomer with pendant benzimidazole groups for fuel cells

    DEFF Research Database (Denmark)

    Li, Wei; Guo, Xiaoxia; Aili, David

    2015-01-01

    . A series of sulfonated copolyimides (SPI) are prepared via random copolymerizatio of 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA) with a new diamine monomer with pendant benzimidazole groups, 2,2'-bis(4-(1H-benzo[d]imidazol-2-yl)phenoxy)benzidine (BIPOB), and a sulfonated diamine monomer 4,4'-bis...

  6. Anion exchange membrane based on alkali doped poly(2,5-benzimidazole) for fuel cell

    CSIR Research Space (South Africa)

    Luo, H

    2012-02-01

    Full Text Available The properties of alkali doped poly(2,5-benzimidazole) membrane with different alkali doping level for fuel cell application is reported in this work. The alkali doping level played an important role for the ion conductivity of the membrane. The ion...

  7. Molecule Matters

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 4. Molecule Matters – van der Waals Molecules - History and Some Perspectives on Intermolecular Forces. E Arunan. Feature Article Volume 14 Issue 4 April 2009 pp 346-356 ...

  8. Molecular characterization, fitness and mycotoxin production of benzimidazole-resistant isolates of Penicillium expansum.

    Science.gov (United States)

    Malandrakis, Anastasios A; Markoglou, Anastasios N; Konstantinou, Sotiris; Doukas, Eleftherios G; Kalampokis, John F; Karaoglanidis, George S

    2013-04-01

    Penicillium expansum field-strains resistant to benzimidazole fungicides were isolated in high frequency from decayed apple fruit collected from packinghouses and processing industries located in the region of Imathia, N. Greece. In vitro fungitoxicity tests resulted in the identification of two different resistant phenotypes: highly (BEN-HR) and moderately (BEN-MR) carbendazim-resistant. Thirty seven percent of the isolated P. expansum strains belonged to the BEN-HR phenotype, carried no apparent fitness penalties and exhibited resistance levels higher than 60 based on EC50 values. Cross resistance studies with other benzimidazole fungicides showed that all BEN-HR and BEN-MR isolates were also less sensitive to benomyl and thiabendazole. Fungitoxicity tests on the response of BEN-HR isolates to fungicides belonging to other chemical classes revealed no cross-resistance relationships between benzimidazoles and the phenylpyrrole fludioxonil, the dicarboximide iprodione, the anilinopyrimidine cyprodinil, the QoI pyraclostrobin, the imidazole imazalil and the triazole tebuconazole, indicating that a target-site modification is probably responsible for the BEN-HR phenotype observed. Contrary to the above, some BEN-MR isolates exhibited an increased sensitivity to cyprodinil compared to benzimidazole-sensitive ones. BEN-MR isolates had fitness parameters similar to the benzimidazole-sensitive isolates except for conidia production which appeared significantly decreased. Analysis of mycotoxin production (patulin and citrinin) showed that all benzimidazole-resistant isolates produced mycotoxins at concentrations significantly higher than sensitive isolates both on culture medium and on artificially inoculated apple fruit. Comparison of the β-tubulin gene DNA sequence between resistant and sensitive isolates revealed a point mutation resulting from the E198A substitution of the corresponding protein in most but not all HR isolates tested. Molecular analysis of the

  9. A thiazepino[4,5-a]benzimidazole derivative hampers the RNA replication of Eurasian serotypes of foot-and-mouth disease virus.

    Science.gov (United States)

    Lefebvre, David J; De Vleeschauwer, Annebel R; Goris, Nesya; Van Borm, Steven; Chimirri, Alba; Monforte, Anna Maria; Valdazo-Gonzalez, Begona; King, Donald P; Neyts, Johan; De Clercq, Kris

    2014-12-12

    The stamping-out policy for the control of foot-and-mouth disease virus (FMDV) in countries that are free from FMD without vaccination has a dramatic socio-economic impact, huge animal welfare issues and may result in the loss of farm animal genetic resources. As an alternative to pre-emptive culling or emergency vaccination we further explore the possibility to use antiviral drugs in the event of an FMD outbreak. In the present study, we tested the in vitro cytotoxicity and anti-FMDV activity of 1,2,4,5-tetrahydro-[1,4]thiazepino[4,5-a]benzimidazole. The molecule was shown to inhibit the replication of reference strains of the Eurasian FMDV serotypes O, A, C and Asia but not the FMDV serotypes from the South African Territories (SAT) neither a related picornavirus, i.e. swine vesicular disease virus. The molecule can be added until 2h post inoculation in a 'single replication cycle experiment' without losing its antiviral activity. The genetic characterization of progressively selected resistant FMD viruses shows that the molecule presumably interacts with the non-structural 2C protein of FMDV. Further studies are required on the use of this molecule in vivo. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Study of the {sup 14}C benzimidazole distribution in mice after inter-peritoneal injection; Etude de la repartition du benzimidazole {sup 14}C chez la souris apres injection intraperitoneale

    Energy Technology Data Exchange (ETDEWEB)

    Tyortyalian, C [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1965-07-01

    In order to provide further information on the mechanism of benzimidazole radioprotective activity, this work studies the tissual repartition in mice of this compound labelled with carbon 14. Experiments have showed that benzimidazole distribution is fast and homogeneous in all the tissues, but however affinity appears at the level of stomach and gastric content. Elimination is made through the urinary system and is very fast. (author) [French] Dans le cadre de l'etude du mecanisme de l'action radioprotectrice du benzimidazole, ce travail a pour objet l'etude de la repartition tissulaire chez la souris de ce compose marque au carbone 14. L'experimentation a montre que le benzimidazole se repartit tres rapidement et de facon pratiquement homogene dans tous les tissus, avec toutefois une affinite paraissant se manifester au niveau de l'estomac et du contenu gastrique. L'elimination, qui se fait par voie urinaire, est tres rapide. (auteur)

  11. Energy storage and redistribution in molecules

    International Nuclear Information System (INIS)

    Hinze, J.

    1983-01-01

    This book presents information on the following topics: chemistry and spectroscopy of molecules at high levels of excitation; energy and phase randomization in large molecules as probed by laser spectroscopy; intramolecular processes in isolated polyatomic molecules; pulse-probe measurements in low-temperature, low-pressure SF 6 ; the photodissociation dynamics of H 2 S and CF 3 NO; photofragment spectroscopy of the NO 2 dissociation; preparation, laser spectroscopy and predissociation of alkali dimers in supersonic nozzle beams; excited states of small molecules - collisional quenching and photodissociation; quantum-state-resolved scattering of lithium hydride; and molecular negative ions

  12. Diversity-Oriented Synthesis of Coumarin-Linked Benzimidazoles via a One-Pot, Three-Step, Intramolecular Knoevenagel Cyclization.

    Science.gov (United States)

    Yao, Po-Hsin Eric; Kumar, Sunil; Liu, Yu-Li; Fang, Chiu-Ping; Liu, Chia-Chen; Sun, Chung-Ming

    2017-04-10

    Diversity-oriented synthesis of coumarin-linked benzimidazoles from N-(2-aminophenyl)-2-cyanoacetamide was achieved via a one-pot, three-step sequential reaction in excellent yields. In situ intramolecular cyclization of the cyanoacetamide afforded benzimidazoles which subsequently underwent a Knoevenagel condensation of the 2-cyanomethylbenzimidazoles with salicylaldehydes promoted by triethylamine to reach the target compounds. An important intermediate, 2-(2-imino-2H-chromen-3-yl)-1H-benzimidazole was characterized by X-ray analysis and further hydrolyzed to 2-(coumarin-3-yl)benzimidazole in acidic condition. Among the synthesized compounds, some were found to be promising inhibitors of porcine kidney d-amino acid oxidase (pkDAO).

  13. Microwave promoted simple, efficient and regioselective synthesis of trisubstituted imidazo[1,2-a]benzimidazoles on soluble support.

    Science.gov (United States)

    Chen, Li-Hsun; Hsiao, Ya-Shan; Yellol, Gorakh S; Sun, Chung-Ming

    2011-03-14

    An efficient microwave-assisted and soluble polymer-supported synthesis of medicinally important imidazole-fused benzimidazoles has been developed. The protocol involves the rapid condensation of polymer-bound amino benzimidazoles with various α-bromoketones and subsequent in situ intramolecular cyclization under microwave irradiation resulting in a one pot synthesis of imidazole interlacing benzimidazole polymer conjugates. The condensed product was obtained with excellent regioselectivity. The biologically interesting imidazo[1,2-a]benzimidazoles was released from polymer support at ambient temperature. Diversity in the triheterocyclic nucleus was achieved by the different substitutions at its 2, 3, and 9 positions. The new protocol has the advantages of short reaction time, easy workup process, excellent yields, reduced environmental impact, wide substrate scope and convenient procedure.

  14. Facile and Selective Synthesis of 2-Substituted Benzimidazoles Catalyzed by FeCl3/ Al2O3

    Directory of Open Access Journals (Sweden)

    Guo-Feng Chen

    2012-01-01

    Full Text Available 2-Substituted benzimidazoles were synthesized in a single pot from aromatic aldehydes and o-phenylenediamine catalyzed by FeCl3/ Al2O3 in DMF at ambient temperature attained good yields and high selectivity.

  15. In Situ formation of pentafluorophosphate benzimidazole anion stabilizes high-temperature performance of lithium-ion batteries

    International Nuclear Information System (INIS)

    Pradanawati, Sylvia Ayu; Wang, Fu-Ming; Rick, John

    2014-01-01

    Highlights: • A new pentafluorophosphate benzimidazole anion was formed by Lewis acid-base reaction. • This pentafluorophosphate benzimidazole anion is fabricated with the benzimidazole anion and PF 5 . • This pentafluorophosphate benzimidazole anion avoids the ominous side reactions that PF 5 reacts SEI to form LiF and HF at high temperature. • The additional pentafluorophosphate benzimidazole anion formation well maintains the battery performance at 60 °C measurement compares to the electrolyte only with contains the salt, LiPF 6 . - Abstract: Lithium salts play a critical role in initiating electrochemical reactions in Li-ion batteries. Single Li ions dissociate from bulk-salt and associate with carbonates to form a solid electrolyte interface (SEI) during the first charge-discharge of the battery. SEI formation and the chemical stability of salt must both be controlled and optimized to minimize irreversible reactions in SEI formation and to suppress the decomposition of the salt at high temperatures. This study synthesizes a new benzimidazole-based anion in the electrolyte. This anion, pentafluorophosphate benzimidazole, results from a Lewis acid-base reaction between the benzimidazole anion and PF 5 . The new pentafluorophosphate benzimidazole anion inhibits the decomposition of LiPF 6 by inhibiting PF 5 side reactions, which degrade the SEI, and lead to the formation of LiF and HF at high temperatures. In addition, the use of the pentafluorophosphate benzimidazole anion results in the formation of a modified SEI that is able to modify the battery's performance. Cyclic voltammetry, scanning electron microscopy, differential scanning calorimetry, electrochemical impedance spectroscopy, as well as charge-discharge and X-ray photoelectron spectroscopy measurements have been used to characterize the materials in this study. The formation of the pentafluorophosphate benzimidazole anion in the electrolyte caused a 14% decrease in the activation energy

  16. Effect of benzimidazol-derivatives on the DNA-protein binding formation after UV-radiation of chromatin

    International Nuclear Information System (INIS)

    Mil', E.M.; Binyukov, V.I.; Zhil'tsova, V.M.; Stolyarova, L.G.; Kuznetsov, Yu.V.

    1991-01-01

    Effect of benzimidazol-derivatives on the DNA-protein binding formation was studied after UV-radiation of chromatin. These derivatives were shown to protect chromatin from UV-induced DNA-protein binding formation. Structural analog contained two aminomethyl residuals sensibilized additional binding formation in chromatin. Results suggested, that benzimidazol interacted with DNA, while aminomethyl groups interacted with protein and sensibilized binding of DNA, whilt aminomethyl groups interacted with protein and sensibilized binding of DNA with histone H1

  17. Probe Storage

    NARCIS (Netherlands)

    Gemelli, Marcellino; Abelmann, Leon; Engelen, Johannes Bernardus Charles; Khatib, M.G.; Koelmans, W.W.; Zaboronski, Olog; Campardo, Giovanni; Tiziani, Federico; Laculo, Massimo

    2011-01-01

    This chapter gives an overview of probe-based data storage research over the last three decades, encompassing all aspects of a probe recording system. Following the division found in all mechanically addressed storage systems, the different subsystems (media, read/write heads, positioning, data

  18. Cultural probes

    DEFF Research Database (Denmark)

    Madsen, Jacob Østergaard

    The aim of this study was thus to explore cultural probes (Gaver, Boucher et al. 2004), as a possible methodical approach, supporting knowledge production on situated and contextual aspects of occupation.......The aim of this study was thus to explore cultural probes (Gaver, Boucher et al. 2004), as a possible methodical approach, supporting knowledge production on situated and contextual aspects of occupation....

  19. Optics and molecules on atom chips

    International Nuclear Information System (INIS)

    Tscherneck, M; Holmes, M E; Quinto-Su, P A; Haimberger, C; Kleinert, J; Bigelow, N P

    2005-01-01

    In this paper we will report on four experiments which have been carried out in the last year in our group. All of these experiments are necessary steps towards the trapping and probing of ultracold molecules on a chip surface

  20. Atkins' molecules

    CERN Document Server

    Atkins, Peters

    2003-01-01

    Originally published in 2003, this is the second edition of a title that was called 'the most beautiful chemistry book ever written'. In it, we see the molecules responsible for the experiences of our everyday life - including fabrics, drugs, plastics, explosives, detergents, fragrances, tastes, and sex. With engaging prose Peter Atkins gives a non-technical account of an incredible range of aspects of the world around us, showing unexpected connections, and giving an insight into how this amazing world can be understood in terms of the atoms and molecules from which it is built. The second edition includes dozens of extra molecules, graphical presentation, and an even more accessible and enthralling account of the molecules themselves.

  1. Interstellar Molecules

    Science.gov (United States)

    Solomon, Philip M.

    1973-01-01

    Radioastronomy reveals that clouds between the stars, once believed to consist of simple atoms, contain molecules as complex as seven atoms and may be the most massive objects in our Galaxy. (Author/DF)

  2. Regio- and Enantioselective N-Allylations of Imidazole, Benzimidazole, and Purine Heterocycles Catalyzed by Single-Component Metallacyclic Iridium Complexes

    Science.gov (United States)

    Stanley, Levi M.

    2010-01-01

    Highly regio- and enantioselective iridium-catalyzed N-allylations of benzimidazoles, imidazoles, and purines have been developed. N-Allylated benzimidazoles and imidazoles were isolated in high yields (up to 97%) with high branched-to-linear selectivity (up to 99:1) and enantioselectivity (up to 98% ee) from the reactions of benzimidazole and imidazole nucleophiles with unsymmetrical allylic carbonates in the presence of single component, ethylene-bound, metallacyclic iridium catalysts. N-Allylated purines were also obtained in high yields (up to 91%) with high N9:N7 selectivity (up to 96:4), high branched-to-linear selectivity (98:2), and high enantioselectivity (up to 98% ee) under similar conditions. The reactions encompass a range of benzimidazole, imidazole, and purine nucleophiles, as well as a variety of unsymmetrical aryl, heteroaryl, and aliphatic allylic carbonates. Competition experiments between common amine nucleophiles and the heterocyclic nitrogen nucleophiles studied in this work illustrate the effect of nucleophile pKa on the rate of iridium-catalyzed N-allylation reactions. Kinetic studies on the allylation of benzimidazole catalyzed by metallacyclic iridium-phosphoramidite complexes, in combination with studies on the deactivation of these catalysts in the presence of heterocyclic nucleophiles, provide insight into the effects of the structure of the phosphoramidite ligands on the stability of the metallacyclic catalysts. The data obtained from these studies has led to the development of N-allylations of benzimidazoles and imidazoles in the absence of an exogenous base. PMID:19480431

  3. Fluorescent silica hybrid materials containing benzimidazole dyes obtained by sol-gel method and high pressure processing

    International Nuclear Information System (INIS)

    Hoffmann, Helena Sofia; Stefani, Valter; Benvenutti, Edilson Valmir; Costa, Tania Maria Haas; Gallas, Marcia Russman

    2011-01-01

    Research highlights: → Sol-gel technique was used to obtain silica based hybrid materials containing benzimidazole dyes. → The sol-gel catalysts, HF and NaF, produce xerogels with different optical and textural characteristics. → High pressure technique (6.0 GPa) was used to produce fluorescent and transparent silica compacts with the dyes entrapped in closed pores, maintaining their optical properties. → The excited state intramolecular proton transfer (ESIPT) mechanism of benzimidazole dyes was studied by steady-state fluorescence spectroscopy for the monoliths, powders, and compacts. - Abstract: New silica hybrid materials were obtained by incorporation of two benzimidazole dyes in the silica network by sol-gel technique, using tetraethylorthosilicate (TEOS) as inorganic precursor. Several syntheses were performed with two catalysts (HF and NaF) producing powders and monoliths with different characteristics. The dye 2-(2'-hydroxy-5'-aminophenyl)benzimidazole was dispersed and physically adsorbed in the matrix, and the dye 2'(5'-N-(3-triethoxysilyl)propylurea-2'-hydroxyphenyl)benzimidazole was silylated, becoming chemically bonded to the silica network. High pressure technique was used to produce fluorescent and transparent silica compacts with the silylated and incorporated dye, at 6.0 GPa and room temperature. The excited state intramolecular proton transfer (ESIPT) mechanism of benzimidazole dyes was studied by steady-state fluorescence spectroscopy for the monoliths, powders, and compacts. The influence of the syntheses conditions was investigated by textural analysis using nitrogen adsorption isotherms.

  4. Exploring 2D and 3D QSARs of benzimidazole derivatives as transient receptor potential melastatin 8 (TRPM8 antagonists using MLR and kNN-MFA methodology

    Directory of Open Access Journals (Sweden)

    Kamlendra Singh Bhadoriya

    2016-09-01

    Full Text Available TRPM8 is now best known as a cold- and menthol-activated channel implicated in thermosensation. TRPM8 is specifically expressed in a subset of pain- and temperature-sensing neuron. TRPM8 plays a major role in the sensation of cold and cooling substances. TRPM8 is a potential new target for the treatment of painful conditions. Thus, TRPM8 antagonists represent a new, novel and potentially useful treatment strategy to treat various disease states such as urological disorders, asthma, COPD, prostate and colon cancers, and painful conditions related to cold, such as cold allodynia and cold hyperalgesia. Better tools such as potent and specific TRPM8 antagonists are mandatory as high unmet medical need for such progress. To achieve this objective quantitative structure–activity relationship (QSAR studies were carried out on a series of 25 benzimidazole-containing TRPM8 antagonists to investigate the structural requirements of their inhibitory activity against cTRPM8. The statistically significant best 2D-QSAR model having correlation coefficient r2 = 0.88 and cross-validated squared correlation coefficient q2 = 0.64 with external predictive ability of pred_r2 = 0.69 was developed by SW-MLR. The physico-chemical descriptors such as polarizabilityAHP, kappa2, XcompDipole, +vePotentialSurfaceArea, XKMostHydrophilic were found to show a significant correlation with biological activity in benzimidazole derivatives. Molecular field analysis was used to construct the best 3D-QSAR model using SW-kNN method, showing good correlative and predictive capabilities in terms of q2 = 0.81 and pred_r2 = 0.55. Developed kNN-MFA model highlighted the importance of shape of the molecules, i.e., steric & electrostatic descriptors at the grid points S_774 & E_1024 for TRPM8 receptor binding. These models (2D & 3D were found to yield reliable clues for further optimization of benzimidazole derivatives in the data set. The information rendered by 2D- and 3D

  5. Microwave-assisted RAFT polymerization of well-constructed magnetic surface molecularly imprinted polymers for specific recognition of benzimidazole residues

    Science.gov (United States)

    Chen, Fangfang; Wang, Jiayu; Chen, Huiru; Lu, Ruicong; Xie, Xiaoyu

    2018-03-01

    Magnetic nanoparticles have been widely used as support core for fast separation, which could be directly separated from complicated matrices using an external magnet in few minutes. Surface imprinting based on magnetic core has shown favorable adsorption and separation performance, including good adsorption capacity, fast adsorption kinetics and special selectivity adsorption. Reversible addition-fragmentation chain transfer (RAFT) is an ideal choice for producing well-defined complex architecture with mild reaction conditions. We herein describe the preparation of well-constructed magnetic molecularly imprinted polymers (MMIPs) for the recognition of benzimidazole (BMZ) residues via the microwave-assisted RAFT polymerization. The merits of RAFT polymerization assisting with microwave heating allowed successful and more efficient preparation of well-constructed imprinted coats. Moreover, the polymerization time dramatically shortened and was just 1/24th of the time taken by conventional heating. The results indicated that a uniform nanoscale imprinted layer was formed on the Fe3O4 core successfully, and enough saturation magnetization of MMIPs (16.53 emu g-1) was got for magnetic separation. The desirable adsorption capacity (30.18 μmol g-1) and high selectivity toward template molecule with a selectivity coefficient (k) of 13.85 of MMIPs were exhibited by the adsorption isothermal assay and competitive binding assay, respectively. A solid phase extraction enrichment approach was successfully established for the determination of four BMZ residues from apple samples using MMIPs coupled to HPLC. Overall, this study provides a versatile approach for highly efficient fabrication of well-constructed MMIPs for enrichment and determination of target molecules from complicated samples.

  6. Synthesis, pharmacological activity evaluation and molecular modeling of new polynuclear heterocyclic compounds containing benzimidazole derivatives.

    Science.gov (United States)

    Bassyouni, Fatma A; Saleh, Tamer S; ElHefnawi, Mahmoud M; Abd El-Moez, Sherein I; El-Senousy, Waled M; Abdel-Rehim, Mohamed E

    2012-12-01

    Novel heterocyclic compounds containing benzimidazole derivatives were synthesized from 2-(1H-benzimidazol-2-yl) acetonitrile (1) and arylhydrazononitrile derivative 2 was obtained via coupling of 1 with 4-methyl phenyldiazonium salt, which was then reacted with hydroxylamine hydrochloride to give amidooxime derivative 3. This product was cyclized into the corresponding oxadiazole derivative 4 upon reflux in acetic anhydride. Compound 4 was refluxed in DMF in the presence of triethylamine to give the corresponding 5-(1H-benzimidazol-2-yl)-2-p-tolyl-2H-1,2,3-triazol-4-amine 6. Treatment of compound 6 with ethyl chloroformate afforded 2,6-dihydro-2-(4-methylphenyl)-1,2,3-triazolo[4",5"-4',5']pyrimido[1,6-a]benzimidazole-5(4H)-one (8). 1,2-bis(2-cyanomethyl-1H-benzimidazol-1-yl)ethane-1,2-dione (10) was synthesized via the condensation reaction of 2-(1H-benzimidazol-2-yl) acetonitrile (1) and diethyloxalate. The reactivity of compound 10 towards some diamine reagents was studied. The in vitro antimicrobial activity of the synthesized compounds was investigated against several pathogenic bacterial strains such as Escherichia coli O157, Salmonella typhimurium, E. coli O119, S. paratyphi, Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes and Bacillus cereus. The results of MIC revealed that compounds 12a-c showed the most effective antimicrobial activity against tested strains. On the other hand, compounds 12a, b exhibited high activity against rotavirus Wa strain while compounds 12b, c exhibited high activity against adenovirus type 7. In silico target prediction, docking and validation of the compounds 12a-c were performed. The dialkylglycine decarboxylase bacterial enzyme was predicted as a potential bacterial target receptor using pharmacophore-based correspondence with previous leads; giving the highest normalized scores and a high correlation docking score with mean inhibition concentrations. A novel binding mechanism was predicted after docking

  7. Mobile probes

    DEFF Research Database (Denmark)

    Ørngreen, Rikke; Jørgensen, Anna Neustrup; Noesgaard, Signe Schack

    2016-01-01

    A project investigating the effectiveness of a collection of online resources for teachers' professional development used mobile probes as a data collection method. Teachers received questions and tasks on their mobile in a dialogic manner while in their everyday context as opposed...... to in an interview. This method provided valuable insight into the contextual use, i.e. how did the online resource transfer to the work practice. However, the research team also found that mobile probes may provide the scaffolding necessary for individual and peer learning at a very local (intra-school) community...... level. This paper is an initial investigation of how the mobile probes process proved to engage teachers in their efforts to improve teaching. It also highlights some of the barriers emerging when applying mobile probes as a scaffold for learning....

  8. Optical probe

    International Nuclear Information System (INIS)

    Denis, J.; Decaudin, J.M.

    1984-01-01

    The probe includes optical means of refractive index n, refracting an incident light beam from a medium with a refractive index n1>n and reflecting an incident light beam from a medium with a refractive index n2 [fr

  9. Adhesion molecules

    CERN Document Server

    Preedy, Victor R

    2016-01-01

    This book covers the structure and classification of adhesion molecules in relation to signaling pathways and gene expression. It discusses immunohistochemical localization, neutrophil migration, and junctional, functional, and inflammatory adhesion molecules in pathologies such as leukocyte decompression sickness and ischemia reperfusion injury. Highlighting the medical applications of current research, chapters cover diabetes, obesity, and metabolic syndrome; hypoxia; kidney disease; smoking, atrial fibrillation, and heart disease, the brain and dementia; and tumor proliferation. Finally, it looks at molecular imaging and bioinformatics, high-throughput technologies, and chemotherapy.

  10. Counting probe

    International Nuclear Information System (INIS)

    Matsumoto, Haruya; Kaya, Nobuyuki; Yuasa, Kazuhiro; Hayashi, Tomoaki

    1976-01-01

    Electron counting method has been devised and experimented for the purpose of measuring electron temperature and density, the most fundamental quantities to represent plasma conditions. Electron counting is a method to count the electrons in plasma directly by equipping a probe with the secondary electron multiplier. It has three advantages of adjustable sensitivity, high sensitivity of the secondary electron multiplier, and directional property. Sensitivity adjustment is performed by changing the size of collecting hole (pin hole) on the incident front of the multiplier. The probe is usable as a direct reading thermometer of electron temperature because it requires to collect very small amount of electrons, thus it doesn't disturb the surrounding plasma, and the narrow sweep width of the probe voltage is enough. Therefore it can measure anisotropy more sensitively than a Langmuir probe, and it can be used for very low density plasma. Though many problems remain on anisotropy, computer simulation has been carried out. Also it is planned to provide a Helmholtz coil in the vacuum chamber to eliminate the effect of earth magnetic field. In practical experiments, the measurement with a Langmuir probe and an emission probe mounted to the movable structure, the comparison with the results obtained in reverse magnetic field by using a Helmholtz coil, and the measurement of ionic sound wave are scheduled. (Wakatsuki, Y.)

  11. Thermodynamics of formation of cadmium dicarboxylate and carboxylate mixed complexes with benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Kharitonov, G V; Bolotov, V M; Kharitonova, R I [Voronezhskij Tekhnologicheskij Inst. (USSR)

    1980-01-01

    Thermodynamic parameters of the mixed complexing of cadmium propionate, butyrate, valerate, succinate, maleinate and malate with benzimidazole in 20 % aqUeous-ethanol solution of 0.1 M KNO/sub 3/ are studied using polarographic method. It is shown that stability of mixed complexes of cadmium carboxylates with benzimidazole is connected with the process enthalpy and is determined by covalency of the metal-carboxylate bond. Increasing length of hydrocarbon chain of acyl group of monobasic acids hampers amine coordination with central complexing agent (..delta..S<0). The presence of dicarboxylate-ion in the inner coordination sphere decreases the enthalpy and increases the entropy of the process (..delta..S>0).

  12. Synthesis and molecular structures of 1-hydroxyethyl-2-(p-substituted) phenoxymethyl benzimidazoles

    International Nuclear Information System (INIS)

    Wu, J.W.; Zhao, L.; Wang, Z.; Gu, H.; Chen, W.; Zhao, C.

    2016-01-01

    Five novel 1-hydroxyethyl-2-(p-substituted) phenoxymethyl benzimidazoles were synthesized by a three-step route. Under microwave irradiation, the p-substituted phenols were firstly O-carboxymethylated to prepare the corresponding p-substituted phenoxymethyl acids, which then reacted with o-phenylendiamine to get the key intermediates 2-(p-substituted) phenoxymethyl benzimidazole. Finally, the solid-liquid phase transfer catalysis method, where tetrabutyl ammonium bromide (TBAB) was used as the catalyst, was applied to synthesize the target compounds c/sub 1/-c/sub 5/ by the N-hydroxyethylation reaction with 2-chloroethyl alcohol. The structures of the obtained compounds were well characterized and confirmed by elemental analysis, MS, IR, /sup 1/H NMR, /sup 13/C NMR and single-crystal X-ray diffraction analysis. (author)

  13. Synthesis, QSAR, and Molecular Dynamics Simulation of Amidino-substituted Benzimidazoles as Dipeptidyl Peptidase III Inhibitors.

    Science.gov (United States)

    Rastija, Vesna; Agić, Dejan; Tomiš, Sanja; Nikolič, Sonja; Hranjec, Marijana; Grace, Karminski-Zamola; Abramić, Marija

    2015-01-01

    A molecular modeling study is performed on series of benzimidazol-based inhibitors of human dipeptidyl peptidase III (DPP III). An eight novel compounds were synthesized in excellent yields using green chemistry approach. This study is aimed to elucidate the structural features of benzimidazole derivatives required for antagonism of human DPP III activity using Quantitative Structure-Activity Relationship (QSAR) analysis, and to understand the mechanism of one of the most potent inhibitor binding into the active site of this enzyme, by molecular dynamics (MD) simulations. The best model obtained includes S3K and RDF045m descriptors which have explained 89.4 % of inhibitory activity. Depicted moiety for strong inhibition activity matches to the structure of most potent compound. MD simulation has revealed importance of imidazolinyl and phenyl groups in the mechanism of binding into the active site of human DPP III.

  14. Synthesis, biological evaluation and molecular modeling investigation of some new Benzimidazole analogs as antiviral agents

    International Nuclear Information System (INIS)

    Goda, Fatma E.; Tantawy, Atif S.; Abou-Zeid, Laila A.; Badr, Sahar M.; Selim, Khalid B.

    2008-01-01

    A set heterocyclic benzimidazole derivatives bearing 1, 3, 5-triazine group with different substituents at C-2 and C-5 of the benzimidazole ring have been synthesized and evaluated for their antiviral activities against HASV-1. The structures of these compounds have been established by analytical data, IR spectra, H NMR and mass spectra. Compounds 8a and 8b proved to be the most active antiherpetic agents in this study, at EC 50% concentrations of 2.9. 3.4 mg/ml, respectively. Computational evaluation of the quantum chemical descriptors such as hydrphobicity (log P), HOMO-LUMO and the gap energy were calculated and correlated with the antiviral activity. The tested compounds showed proper degree of hydrophobicity ( 5). The HOMO-LUMO gap energy values of the tested compounds are comparable with the observed values for the antiviral drug Acyclovir. (author)

  15. Molecule Matters

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 12. Molecule Matters - Dinitrogen. A G Samuelson J Jabadurai. Volume 16 Issue 12 ... Author Affiliations. A G Samuelson1 J Jabadurai1. Department of Inroganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India.

  16. Molecule Matters

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 9. Molecule Matters - A Chromium Compound with a Quintuple Bond. K C Kumara Swamy. Feature Article Volume 11 Issue 9 September 2006 pp 72-75. Fulltext. Click here to view fulltext PDF. Permanent link:

  17. Halide/pseudohalide complexes of cadmium(II) with benzimidazole: Synthesis, crystal structures and fluorescence properties

    Science.gov (United States)

    Zhao, Hai-Yan; Yang, Fu-Li; Li, Na; Wang, Xiao-Jing

    2017-11-01

    Two new dinuclear Cd(II) complexes, [CdL1Cl2]2·H2O (1) and [CdL1(N3)2]2·CH3OH (2) and one dicyanamide bridged one-dimensional polynuclear network [CdL1(μ1,5-dca)dca]n (3) of the potentially tridentate NNN-donor Schiff base 2-((1H-benzimidazol-2-yl-ethylimino)-methyl)pyridine (L1) and another dinucler Cd(II) complex [CdL2Cl(dca)]2 (4) of a similar NNN-donor Schiff base ligand 2-((1H-benzimidazol-2-yl-propylimino)-methyl)pyridine (L2), have been synthesized and characterized by elemental analyses, IR and single crystal X-ray crystallography. The ligands L1 and L2 are [1 + 1] condensation products of pyridine-2-carbaldehyde with 2-aminoethyl-1H-benzimidazole and 2-aminopropyl-1H-benzimidazole, respectively. In the complexes 1 and 4 the two Cd(II) centers are held together by the bridged chloride ligands, while in 2 the two Cd(II) centers are bridged by μ1,1-azide ions. Complex 3 has a one-dimensional infinite chain structure in which Cd(II) ions are bridged by single dicyanamide groups in end-to-end fashion. All the metal centers have a distorted octahedral geometry and H-bonding or π⋯π interactions are operative to bind the complex units in the solid state. Furthermore, these complexes have been investigated by thermogravimetric analyses and fluorescence spectra.

  18. Phosphorylated benzimedazoles. 8. Synthesis of phosphorylated with /sup 32/P benzimidazoles

    Energy Technology Data Exchange (ETDEWEB)

    Makarov, A M; Matevosyan, G L; Zavlin, P M [Leningradskij Sel' skokhozyajstvennyj Inst. (USSR)

    1983-03-01

    Accessible methods of synthesis and identification of phosphorylated benzimidazoles with specific activity close to the maximum permissible with labelled /sup 32/P are developed. These methods permit to determine the permissible residual amounts of the above preparations in nutrition products and the maximum permissible amounts of growth regulators in different objects of the environment, because it is impossible to detect, for example, tri(1-benzimidazolido)phosphate with other physico-chemical methods with the existing concentration of 10/sup -9/%.

  19. Mild and Efficient One Pot Synthesis of Imidazolinesand Benzimidazoles from Aldehydes

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2007-01-01

    Full Text Available A series of some imidazolines and benzimidazoles were synthesizedfrom various aldehydes and 1,2-diamines in the presence of ceric(IVammonium nitrate (CAN. The title compounds were prepared via one stepsynthesis method. The simplicity of the reaction conditions with shorterreaction time and with out use of column chromatography to get the pureproducts in high yields makes this method more attractive for organic chemists.

  20. 99mTc complexes of benzimidazole and benzoxazole ligands and their biodistribution studies

    International Nuclear Information System (INIS)

    Kothari, K.; Manju, S.; Pillai, M.R.A.; Rath, N.; Dash, K.C.; Sarma, H.D.

    1997-01-01

    Complexation studies of 2 (2' -hydroxyphenyl)benzimidazole (HPBI) and 2(2' -pyridyl)benzoxazole (PBO) with 99m Tc were carried out. The complexes were characterised by TLC, paper electrophoresis and solvent extraction. The ligand HPBI forms complex in high yield (>90%). Biodistribution studies carried out with 99m Tc-HPBI complex in Swiss Albino mice showed rapid clearance of the complex from blood and excretion of the activity through hepatobiliary system. (author). 2 refs., 1 fig., 3 tabs

  1. Complexes of molybdenum(III) with 2-(2'-pyridyl)benzimidazole

    International Nuclear Information System (INIS)

    Ghosh, S.P.; Prasad, K.M.

    1979-01-01

    Molybdenum(III) forms with 2-(2'-pyridyl) benzimidazole(LH) the trischelated complexes, [Mo(LH) 3 ]X 3 as well as the cationic-anionic complexes, [Mo(LH) 3 X 2 ] + [Mo(LH)X 4 ] - (X=Cl - ,Br - or NCS - ), depending on pH. These complexes have been synthesised and characterised from elemental analyses, i.r. and electronic spectra, magnetic moments and molar conductance. (auth.)

  2. Nanoscale methods for single-molecule electrochemistry.

    Science.gov (United States)

    Mathwig, Klaus; Aartsma, Thijs J; Canters, Gerard W; Lemay, Serge G

    2014-01-01

    The development of experiments capable of probing individual molecules has led to major breakthroughs in fields ranging from molecular electronics to biophysics, allowing direct tests of knowledge derived from macroscopic measurements and enabling new assays that probe population heterogeneities and internal molecular dynamics. Although still somewhat in their infancy, such methods are also being developed for probing molecular systems in solution using electrochemical transduction mechanisms. Here we outline the present status of this emerging field, concentrating in particular on optical methods, metal-molecule-metal junctions, and electrochemical nanofluidic devices.

  3. Novel organic dyes based on phenyl-substituted benzimidazole for dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Saltan, Gözde Murat [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Dinçalp, Haluk, E-mail: haluk.dincalp@cbu.edu.tr [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Kıran, Merve; Zafer, Ceylan [Solar Energy Institute, Ege University, Bornova, 35100 Izmir (Turkey); Erbaş, Seçil Çelik [Celal Bayar University, Materials Engineering Department, Faculty of Engineering, Yunus Emre, 45140 Manisa (Turkey)

    2015-08-01

    Two new sensitizers derived from benzimidazole core for dye-sensitized solar cell (DSSC) applications were designed and synthesized as D–π–A structures, in which two phenyl-substituted benzimidazole group, a phenyl ring and a cyanoacrylic acid were used as the electron donor, π-conjugated linkage and the electron acceptor, respectively. Effect of methoxy- and N,N-dimetylamino- moieties attached to the phenyl groups of benzimidazole were investigated by means of optical and photovoltaic measurements. The compounds exhibit broad absorption maximum at 387 nm with the tail extending up to 500 nm on TiO{sub 2}-coated thin film. The longer wavelength absorption band around 360 nm and the much longer decay components could be attributed to the existence of charge transfer state of the dyes in solutions. DSSC device fabricated by using methoxy substituted dye (BI5a) as a sensitizer shows much better incident photon-to-current conversion efficiency (IPCE) of 64% giving cell efficiency of 2.68%. - Graphical abstract: Display Omitted - Highlights: • Long decay times suggest the delayed fluorescence caused by the existence of ICT. • The best solar energy conversion efficiency was obtained for BI5a dye (2.68%). • More fluorescent BI5a dye gives higher photocurrent generation.

  4. Synthesis, antimicrobial and cytotoxic activity of novel azetidine-2-one derivatives of 1H-benzimidazole

    Directory of Open Access Journals (Sweden)

    Malleshappa Noolvi

    2014-04-01

    Full Text Available A series of 1-methyl-N-[(substituted-phenylmethylidene-1H-benzimidazol-2-amines (4a–4g were prepared via the formation of 1-methyl-1H-benzimidazol-2-amine (3, which was prepared by the cycloaddition of o-phenylenediamine (1 with cyanogen bromide in the presence of aqueous base followed by N-methylation with methyl iodide in the presence of anhydrous potassium carbonate in dry acetonitrile. Moreover, the four-membered β-lactam ring was introduced by the cycloaddition of 4a–4g and chloroacetyl chloride in the presence of triethylamine catalyst to give 3-chloro-1-(1-methyl-1H-benzimidazol-2-yl-(4′-substituted-phenylazetidin-2-one 5a–5g. A total of 14 compounds were synthesized and characterized by IR, 1H NMR, 13C NMR and Mass spectral technique, in addition they were evaluated for anti-bacterial and cytotoxic properties. Among the chemicals tested 4a, 4b, 5a, 5b, 5g exhibited good antibacterial activity and 5f, 5g shown good cytotoxic activity in vitro.

  5. Novel organic dyes based on phenyl-substituted benzimidazole for dye sensitized solar cells

    International Nuclear Information System (INIS)

    Saltan, Gözde Murat; Dinçalp, Haluk; Kıran, Merve; Zafer, Ceylan; Erbaş, Seçil Çelik

    2015-01-01

    Two new sensitizers derived from benzimidazole core for dye-sensitized solar cell (DSSC) applications were designed and synthesized as D–π–A structures, in which two phenyl-substituted benzimidazole group, a phenyl ring and a cyanoacrylic acid were used as the electron donor, π-conjugated linkage and the electron acceptor, respectively. Effect of methoxy- and N,N-dimetylamino- moieties attached to the phenyl groups of benzimidazole were investigated by means of optical and photovoltaic measurements. The compounds exhibit broad absorption maximum at 387 nm with the tail extending up to 500 nm on TiO 2 -coated thin film. The longer wavelength absorption band around 360 nm and the much longer decay components could be attributed to the existence of charge transfer state of the dyes in solutions. DSSC device fabricated by using methoxy substituted dye (BI5a) as a sensitizer shows much better incident photon-to-current conversion efficiency (IPCE) of 64% giving cell efficiency of 2.68%. - Graphical abstract: Display Omitted - Highlights: • Long decay times suggest the delayed fluorescence caused by the existence of ICT. • The best solar energy conversion efficiency was obtained for BI5a dye (2.68%). • More fluorescent BI5a dye gives higher photocurrent generation

  6. Design, synthesis, α-glucosidase inhibitory activity, molecular docking and QSAR studies of benzimidazole derivatives

    Science.gov (United States)

    Dinparast, Leila; Valizadeh, Hassan; Bahadori, Mir Babak; Soltani, Somaieh; Asghari, Behvar; Rashidi, Mohammad-Reza

    2016-06-01

    In this study the green, one-pot, solvent-free and selective synthesis of benzimidazole derivatives is reported. The reactions were catalyzed by ZnO/MgO containing ZnO nanoparticles as a highly effective, non-toxic and environmentally friendly catalyst. The structure of synthesized benzimidazoles was characterized using spectroscopic technics (FT-IR, 1HNMR, 13CNMR). Synthesized compounds were evaluated for their α-glucosidase inhibitory potential. Compounds 3c, 3e, 3l and 4n were potent inhibitors with IC50 values ranging from 60.7 to 168.4 μM. In silico studies were performed to explore the binding modes and interactions between enzyme and synthesized benzimidazoles. Developed linear QSAR model based on density and molecular weight could predict bioactivity of newly synthesized compounds well. Molecular docking studies revealed the availability of some hydrophobic interactions. In addition, the bioactivity of most potent compounds had good correlation with estimated free energy of binding (ΔGbinding) which was calculated according to docked best conformations.

  7. A Trisubstituted Benzimidazole Cell Division Inhibitor with Efficacy against Mycobacterium tuberculosis

    Science.gov (United States)

    Knudson, Susan E.; Awasthi, Divya; Kumar, Kunal; Carreau, Alexandra; Goullieux, Laurent; Lagrange, Sophie; Vermet, Hélèn; Ojima, Iwao; Slayden, Richard A.

    2014-01-01

    Trisubstituted benzimidazoles have demonstrated potency against Gram-positive and Gram-negative bacterial pathogens. Previously, a library of novel trisubstituted benzimidazoles was constructed for high throughput screening, and compounds were identified that exhibited potency against M. tuberculosis H37Rv and clinical isolates, and were not toxic to Vero cells. A new series of 2-cyclohexyl-5-acylamino-6-N, N-dimethylaminobenzimidazoles derivatives has been developed based on SAR studies. Screening identified compounds with potency against M. tuberculosis. A lead compound from this series, SB-P17G-A20, was discovered to have an MIC of 0.16 µg/mL and demonstrated efficacy in the TB murine acute model of infection based on the reduction of bacterial load in the lungs and spleen by 1.73±0.24 Log10 CFU and 2.68±Log10 CFU, respectively, when delivered at 50 mg/kg by intraperitoneal injection (IP) twice daily (bid). The activity of SB-P17G-A20 was determined to be concentration dependent and to have excellent stability in mouse and human plasma, and liver microsomes. Together, these studies demonstrate that SB-P17G-A20 has potency against M. tuberculosis clinical strains with varying susceptibility and efficacy in animal models of infection, and that trisubstituted benzimidazoles continue to be a platform for the development of novel inhibitors with efficacy. PMID:24736743

  8. Imidazoles and benzimidazoles as tubulin-modulators for anti-cancer therapy.

    Science.gov (United States)

    Torres, Fernando C; García-Rubiño, M Eugenia; Lozano-López, César; Kawano, Daniel F; Eifler-Lima, Vera L; von Poser, Gilsane L; Campos, Joaquín M

    2015-01-01

    Imidazoles and benzimidazoles are privileged heterocyclic bioactive compounds used with success in the clinical practice of innumerous diseases. Although there are many advancements in cancer therapy, microtubules remain as one of the few macromolecular targets validated for planning active anti-cancer compounds, and the design of drugs that modulate microtubule dynamics in unknown sites of tubulin is one of the goals of the medicinal chemistry. The discussion of the role of new and commercially available imidazole and benzimidazole derivatives as tubulin modulators is scattered throughout scientific literature, and indicates that these compounds have a tubulin modulation mechanism different from that of tubulin modulators clinically available, such as paclitaxel, docetaxel, vincristine and vinblastine. In fact, recent literature indicates that these derivatives inhibit microtubule formation binding to the colchicine site, present good pharmacokinetic properties and are capable of overcoming multidrug resistance in many cell lines. The understanding of the mechanisms involved in the imidazoles/benzimidazoles modulation of microtubule dynamics is very important to develop new strategies to overcome the resistance to anti-cancer drugs and to discover new biomarkers and targets for cancer chemotherapy.

  9. Novel trisubstituted benzimidazoles, targeting Mtb FtsZ, as a new class of antitubercular agents.

    Science.gov (United States)

    Kumar, Kunal; Awasthi, Divya; Lee, Seung-Yub; Zanardi, Ilaria; Ruzsicska, Bela; Knudson, Susan; Tonge, Peter J; Slayden, Richard A; Ojima, Iwao

    2011-01-13

    Libraries of novel trisubstituted benzimidazoles were created through rational drug design. A good number of these benzimidazoles exhibited promising MIC values in the range of 0.5-6 μg/mL (2-15 μM) for their antibacterial activity against Mtb H37Rv strain. Moreover, five of the lead compounds also exhibited excellent activity against clinical Mtb strains with different drug-resistance profiles. All lead compounds did not show appreciable cytotoxicity (IC(50) > 200 μM) against Vero cells, which inhibited Mtb FtsZ assembly in a dose dependent manner. The two lead compounds unexpectedly showed enhancement of the GTPase activity of Mtb FtsZ. The result strongly suggests that the increased GTPase activity destabilizes FtsZ assembly, leading to efficient inhibition of FtsZ polymerization and filament formation. The TEM and SEM analyses of Mtb FtsZ and Mtb cells, respectively, treated with a lead compound strongly suggest that lead benzimidazoles have a novel mechanism of action on the inhibition of Mtb FtsZ assembly and Z-ring formation.

  10. A trisubstituted benzimidazole cell division inhibitor with efficacy against Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Susan E Knudson

    Full Text Available Trisubstituted benzimidazoles have demonstrated potency against Gram-positive and Gram-negative bacterial pathogens. Previously, a library of novel trisubstituted benzimidazoles was constructed for high throughput screening, and compounds were identified that exhibited potency against M. tuberculosis H37Rv and clinical isolates, and were not toxic to Vero cells. A new series of 2-cyclohexyl-5-acylamino-6-N, N-dimethylaminobenzimidazoles derivatives has been developed based on SAR studies. Screening identified compounds with potency against M. tuberculosis. A lead compound from this series, SB-P17G-A20, was discovered to have an MIC of 0.16 µg/mL and demonstrated efficacy in the TB murine acute model of infection based on the reduction of bacterial load in the lungs and spleen by 1.73 ± 0.24 Log10 CFU and 2.68 ± Log10 CFU, respectively, when delivered at 50 mg/kg by intraperitoneal injection (IP twice daily (bid. The activity of SB-P17G-A20 was determined to be concentration dependent and to have excellent stability in mouse and human plasma, and liver microsomes. Together, these studies demonstrate that SB-P17G-A20 has potency against M. tuberculosis clinical strains with varying susceptibility and efficacy in animal models of infection, and that trisubstituted benzimidazoles continue to be a platform for the development of novel inhibitors with efficacy.

  11. Effect of chemicals (benzimidazole, methyl thiophanate and potassium) in reducing ozone injury to vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Shibukawa, S; Ota, Y

    1973-01-01

    Following the previous report on the effect of methyl thiophanate for reducing the damages of photochemical oxidants on agricultural produce, effective concentrations and time factors were studied, and the results were compared with that of benzimidazole. Spinach and radishes were grown in pots, and 21, 11, 6, and 3 days prior to ozone exposure tests, 6.25-100 micrograms of benzimidazole and 77.5-310 micrograms of methyl thiophanate solutions were injected into the various pot soils. Exposure to 0.25 ppm O/sub 3/ was given for four hours to spinach and for 2.5 hours to radishes. In all cases, benzimidazole showed a remarkable effect on reducing the damages of O/sub 3/, especially when injected 5-11 days prior to the exposure. Methyl thiophanate was very effective for radishes but had no effect on spinach. Whether this was due to an insufficient amount of chemicals or due to its selectivity is not clear at this stage of the experiments.

  12. Effect of substituted benzimidazoles on acid secretion in isolated and enriched guinea pig parietal cells.

    Science.gov (United States)

    Sewing, K F; Harms, P; Schulz, G; Hannemann, H

    1983-01-01

    The inhibitory effect of the three benzimidazole derivatives timoprazole, picoprazole, and omeprazole on histamine and dbcAMP stimulated 14C-aminopyrine accumulation (= H+ secretion) has been studied in isolated and enriched guinea-pig parietal cells. All compounds tested inhibited H+ secretion in a concentration dependent manner with IC50 values of 8.5 +/- 1.9 mumol/l for timoprazole, 3.9 +/- 0.7 mumol/l for picoprazole, and 0.13 +/- 0.03 mumol/l for omeprazole. The IC50 of timoprazole, when dbcAMP was used as a stimulus, did not differ significantly from that of histamine stimulation. The type of inhibition was of a non-competitive nature. The full acid response to histamine after temporary exposure of the cells to the benzimidazoles could be restored by washing the cells twice; this suggests that the inhibition is reversible. The data - among others - indicate that the properties of the benzimidazoles described here would allow these compounds to be used as effective antisecretagogues. PMID:6303916

  13. Growth Inhibition of Sporomusa ovata by Incorporation of Benzimidazole Bases into Cobamides

    Science.gov (United States)

    Mok, Kenny C.

    2013-01-01

    Phenolyl cobamides are unique members of a class of cobalt-containing cofactors that includes vitamin B12 (cobalamin). Cobamide cofactors facilitate diverse reactions in prokaryotes and eukaryotes. Phenolyl cobamides are structurally and chemically distinct from the more commonly used benzimidazolyl cobamides such as cobalamin, as the lower axial ligand is a phenolic group rather than a benzimidazole. The functional significance of this difference is not well understood. Here we show that in the bacterium Sporomusa ovata, the only organism known to synthesize phenolyl cobamides, several cobamide-dependent acetogenic metabolisms have a requirement or preference for phenolyl cobamides. The addition of benzimidazoles to S. ovata cultures results in a decrease in growth rate when grown on methanol, 3,4-dimethoxybenzoate, H2 plus CO2, or betaine. Suppression of native p-cresolyl cobamide synthesis and production of benzimidazolyl cobamides occur upon the addition of benzimidazoles, indicating that benzimidazolyl cobamides are not functionally equivalent to the phenolyl cobamide cofactors produced by S. ovata. We further show that S. ovata is capable of incorporating other phenolic compounds into cobamides that function in methanol metabolism. These results demonstrate that S. ovata can incorporate a wide range of compounds as cobamide lower ligands, despite its preference for phenolyl cobamides in the metabolism of certain energy substrates. To our knowledge, S. ovata is unique among cobamide-dependent organisms in its preferential utilization of phenolyl cobamides. PMID:23417488

  14. Synthesis and in Vitro Antiproliferative Evaluation of Some B-norcholesteryl Benzimidazole and Benzothiazole Derivatives

    Directory of Open Access Journals (Sweden)

    Jianguo Cui

    2015-04-01

    Full Text Available Taking orostanal (a compound from a Japanese marine sponge, Stelletta hiwasaensis as a lead compound, some novel B-norcholesteryl benzimidazole and benzothiazole derivatives were synthesized. The antiproliferative activity of the compounds against human cervical carcinoma (HeLa, human lung carcinoma (A549, human liver carcinoma cells (HEPG2 and normal kidney epithelial cells (HEK293T was assayed. The results revealed that the benzimidazole group was a better substituent than benzothiazole group for increasing the antiproliferative activity of compounds. 2-(3β′-Acetoxy-5β′-hydroxy-6′-B-norcholesterylbenzimidazole (9b with the structure of 6-benzimidazole displays the best antiproliferative activity to the cancer cells in all compounds, but is almost inactive to normal kidney epithelial cells (HEK293T. The assay of compound 9b to cancer cell apoptosis by flow cytometry showed that the compound was able to effectively induce cancer cell apoptosis. The research provided a theoretical reference for the exploration of new anti-cancer agents and may be useful for the design of novel chemotherapeutic drugs.

  15. DNA probes

    International Nuclear Information System (INIS)

    Castelino, J.

    1992-01-01

    The creation of DNA probes for detection of specific nucleotide segments differs from ligand detection in that it is a chemical rather than an immunological reaction. Complementary DNA or RNA is used in place of the antibody and is labelled with 32 P. So far, DNA probes have been successfully employed in the diagnosis of inherited disorders, infectious diseases, and for identification of human oncogenes. The latest approach to the diagnosis of communicable and parasitic infections is based on the use of deoxyribonucleic acid (DNA) probes. The genetic information of all cells is encoded by DNA and DNA probe approach to identification of pathogens is unique because the focus of the method is the nucleic acid content of the organism rather than the products that the nucleic acid encodes. Since every properly classified species has some unique nucleotide sequences that distinguish it from every other species, each organism's genetic composition is in essence a finger print that can be used for its identification. In addition to this specificity, DNA probes offer other advantages in that pathogens may be identified directly in clinical specimens

  16. DNA probes

    Energy Technology Data Exchange (ETDEWEB)

    Castelino, J

    1993-12-31

    The creation of DNA probes for detection of specific nucleotide segments differs from ligand detection in that it is a chemical rather than an immunological reaction. Complementary DNA or RNA is used in place of the antibody and is labelled with {sup 32}P. So far, DNA probes have been successfully employed in the diagnosis of inherited disorders, infectious diseases, and for identification of human oncogenes. The latest approach to the diagnosis of communicable and parasitic infections is based on the use of deoxyribonucleic acid (DNA) probes. The genetic information of all cells is encoded by DNA and DNA probe approach to identification of pathogens is unique because the focus of the method is the nucleic acid content of the organism rather than the products that the nucleic acid encodes. Since every properly classified species has some unique nucleotide sequences that distinguish it from every other species, each organism`s genetic composition is in essence a finger print that can be used for its identification. In addition to this specificity, DNA probes offer other advantages in that pathogens may be identified directly in clinical specimens 10 figs, 2 tabs

  17. Low power optical limiting studies on nanocrystalline benzimidazole ...

    Indian Academy of Sciences (India)

    Optical limiting studies were performed using the same laser source and the ... activities.7 However, for the last two decades much attention ... the substrate, to control the number of molecules striking the ..... ESA which is a common behaviour in CW regime. ... urable absorption whereas nonlinear refraction leads to self-.

  18. MPAI (mass probes aided ionization) method for total analysis of biomolecules by mass spectrometry.

    Science.gov (United States)

    Honda, Aki; Hayashi, Shinichiro; Hifumi, Hiroki; Honma, Yuya; Tanji, Noriyuki; Iwasawa, Naoko; Suzuki, Yoshio; Suzuki, Koji

    2007-01-01

    We have designed and synthesized various mass probes, which enable us to effectively ionize various molecules to be detected with mass spectrometry. We call the ionization method using mass probes the "MPAI (mass probes aided ionization)" method. We aim at the sensitive detection of various biological molecules, and also the detection of bio-molecules by a single mass spectrometry serially without changing the mechanical settings. Here, we review mass probes for small molecules with various functional groups and mass probes for proteins. Further, we introduce newly developed mass probes for proteins for highly sensitive detection.

  19. Synthesis of 1,2-Disubstituted Benzimidazoles in the Presence of SBA-Pr-SO3H as a Nano Solid Acid Catalyst

    Directory of Open Access Journals (Sweden)

    G. Mohammadi Ziarani

    2012-06-01

    Full Text Available In this article, simple, convenient synthesis of 2-aryl-1- arylmethyl-1H-1,3-benzimidazole (1,2-disubstituted benzimidazoles via condensation of 1,2-phenylenediamine and aromatic aldehydes using SBA-Pr-SO3H as a nanoporous solid acid catalyst in green protocol was reported.

  20. Conjugation of Benzylvanillin and Benzimidazole Structure Improves DNA Binding with Enhanced Antileukemic Properties

    Science.gov (United States)

    Al-Mudarris, Ban A.; Chen, Shih-Hsun; Liang, Po-Huang; Osman, Hasnah; Jamal Din, Shah Kamal Khan; Abdul Majid, Amin M. S.

    2013-01-01

    Benzyl-o-vanillin and benzimidazole nucleus serve as important pharmacophore in drug discovery. The benzyl vanillin (2-(benzyloxy)-3-methoxybenzaldehyde) compound shows anti-proliferative activity in HL60 leukemia cancer cells and can effect cell cycle progression at G2/M phase. Its apoptosis activity was due to disruption of mitochondrial functioning. In this study, we have studied a series of compounds consisting of benzyl vanillin and benzimidazole structures. We hypothesize that by fusing these two structures we can produce compounds that have better anticancer activity with improved specificity particularly towards the leukemia cell line. Here we explored the anticancer activity of three compounds namely 2-(2-benzyloxy-3-methoxyphenyl)-1H-benzimidazole, 2MP, N-1-(2-benzyloxy-3-methoxybenzyl)-2-(2-benzyloxy-3-methoxyphenyl)-1H-benzimidazole, 2XP, and (R) and (S)-1-(2-benzyloxy-3-methoxyphenyl)-2, 2, 2-trichloroethyl benzenesulfonate, 3BS and compared their activity to 2-benzyloxy-3-methoxybenzaldehyde, (Bn1), the parent compound. 2XP and 3BS induces cell death of U937 leukemic cell line through DNA fragmentation that lead to the intrinsic caspase 9 activation. DNA binding study primarily by the equilibrium binding titration assay followed by the Viscosity study reveal the DNA binding through groove region with intrinsic binding constant 7.39 µM/bp and 6.86 µM/bp for 3BS and 2XP respectively. 2XP and 3BS showed strong DNA binding activity by the UV titration method with the computational drug modeling showed that both 2XP and 3BS failed to form any electrostatic linkages except via hydrophobic interaction through the minor groove region of the nucleic acid. The benzylvanillin alone (Bn1) has weak anticancer activity even after it was combined with the benzimidazole (2MP), but after addition of another benzylvanillin structure (2XP), stronger activity was observed. Also, the combination of benzylvanillin with benzenesulfonate (3BS) significantly improved the

  1. Conductivity Probe

    Science.gov (United States)

    2008-01-01

    The Thermal and Electrical Conductivity Probe (TECP) for NASA's Phoenix Mars Lander took measurements in Martian soil and in the air. The needles on the end of the instrument were inserted into the Martian soil, allowing TECP to measure the propagation of both thermal and electrical energy. TECP also measured the humidity in the surrounding air. The needles on the probe are 15 millimeters (0.6 inch) long. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  2. Structure-activity studies of dicationically substituted bis-benzimidazoles against Giardia lamblia: correlation of antigiardial activity with DNA binding affinity and giardial topoisomerase II inhibition.

    Science.gov (United States)

    Bell, C A; Dykstra, C C; Naiman, N A; Cory, M; Fairley, T A; Tidwell, R R

    1993-01-01

    Nine dicationically substituted bis-benzimidazoles were examined for their in vitro activities against Giardia lamblia WB (ATCC 30957). The potential mechanisms of action of these compounds were evaluated by investigating the relationship among in vitro antigiardial activity and the affinity of the molecules for DNA and their ability to inhibit the activity of giardial topoisomerase II. Each compound demonstrated antigiardial activity, as measured by assessing the incorporation of [methyl-3H]thymidine by giardial trophozoites exposed to the test agents. Three compounds exhibited excellent in vitro antigiardial activities, with 50% inhibitory concentrations which compared very favorably with those of two currently used drugs, quinacrine HCl and metronidazole. Putative mechanisms of action for these compounds were suggested by the strong correlation observed among in vitro antigiardial activity and the affinity of the molecules for natural and synthetic DNA and their ability to inhibit the relaxation activity of giardial topoisomerase II. A strong correlation between the DNA binding affinity of these compounds and their inhibition of giardial topoisomerase II activity was also observed. Images PMID:8109934

  3. Probe specificity

    International Nuclear Information System (INIS)

    Laget, J.M.

    1986-11-01

    Specificity and complementarity of hadron and electron probes must be systematically developed to answer three questions currently asked in intermediate energy nuclear physics: what is nucleus structure at short distances, what is nature of short range correlations, what is three body force nature [fr

  4. 2-(1H-Benzimidazol-2-ylphenol

    Directory of Open Access Journals (Sweden)

    S. M. Prakash

    2014-02-01

    Full Text Available The title molecule, C13H10N2O, is essentially planar, the maximum deviation from the plane of the non-H atoms being 0.016 (2 Å. The imidazole ring makes a dihedral angle of 0.37 (13° with the attached benzene ring. An intramolecular O—H...N hydrogen bond generates an S(6 ring motif. In the crystal, molecules are linked through N—H...O hydrogen bonds, forming chains propagating in [001]. The crystal packing also features four π–π stacking interactions involving the imidazole ring, fused benzene ring and attached benzene ring system [centroid–centroid distances = 3.6106 (17, 3.6108 (17, 3.6666 (17 and 3.6668 (17 Å].

  5. Ionization probes of molecular structure and chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, P.M. [State Univ. of New York, Stony Brook (United States)

    1993-12-01

    Various photoionization processes provide very sensitive probes for the detection and understanding of the spectra of molecules relevant to combustion processes. The detection of ionization can be selective by using resonant multiphoton ionization or by exploiting the fact that different molecules have different sets of ionization potentials. Therefore, the structure and dynamics of individual molecules can be studied even in a mixed sample. The authors are continuing to develop methods for the selective spectroscopic detection of molecules by ionization, and to use these methods for the study of some molecules of combustion interest.

  6. Concurrent coordination of ligand in metal chloride complexes with 1-vinyl-2-(2-pyridyl)benzimidazole

    International Nuclear Information System (INIS)

    Bajkalov, L.V.; Domnina, E.S.

    1996-01-01

    The properties and structure of bivalent cadmium and 1-vinyl-2-(2-pyridyl)benzimidazole chloride complexes, which have been prepared for the first time, have been studied by the methods of potentiometric titration and PMR, 35 Cl NQR, UV and IR spectroscopy. For the complexes above di- and polymeric structures in crystal phase are suggested, where ligand plays the role of a bridge. N,N-bidentate ligand. In solution the complexes dissociate with formation of monomeric coordination compounds, their metal being bound by different ways, stemming from participation of N benzimidazole or pyridine fragment of the ligand. Adducts of ionic type with second sphere 1-vinyl-2-(2-pyridyl)benzimidazole cation have been obtained in the course of hydrochlorination of the complexes prepared

  7. Synthesis of benzimidazoles by PIDA-promoted direct C(sp2)-H imidation of N-arylamidines.

    Science.gov (United States)

    Huang, Jinbo; He, Yimiao; Wang, Yong; Zhu, Qiang

    2012-10-29

    A metal-free synthesis of diversified benzimidazoles from N-arylamidines through a phenyliodine(III) diacetate (PIDA) promoted intramolecular direct C(sp(2))-H imidation has been developed. The reaction proceeds smoothly at 0 °C or ambient temperature to provide the desired products in good to excellent yields. The synthesis of 2-alkyl- or 2-alkyl-fused benzimidazoles, which are generally inaccessible by similar Pd- or Cu-catalyzed approaches, can also be achieved. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. The synthesis of benzimidazoles and quinoxalines from aromatic diamines and alcohols by iridium-catalyzed acceptorless dehydrogenative alkylation.

    Science.gov (United States)

    Hille, Toni; Irrgang, Torsten; Kempe, Rhett

    2014-05-05

    Benzimidazoles and quinoxalines are important N-heteroaromatics with many applications in pharmaceutical and chemical industry. Here, the synthesis of both classes of compounds starting from aromatic diamines and alcohols (benzimidazoles) or diols (quinoxalines) is reported. The reactions proceed through acceptorless dehydrogenative condensation steps. Water and two equivalents of hydrogen are liberated in the course of the reactions. An Ir complex stabilized by the tridentate P^N^P ligand N(2) ,N(6) -bis(di-isopropylphosphino)pyridine-2,6-diamine revealed the highest catalytic activity for both reactions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Aqueous Synthesis of 1-H-2-Substituted Benzimidazoles via Transition-Metal-Free Intramolecular Amination of Aryl Iodides

    Directory of Open Access Journals (Sweden)

    Chunxia Chen

    2012-10-01

    Full Text Available A straightforward method has been developed for the synthesis of the benzimidazole ring system through a carbon-nitrogen cross-coupling reaction. In the presence of 2.0 equiv. of K2CO3 in water at 100 °C for 30 h, the intramolecular cyclization of N-(2-iodoarylbenzamidine provides benzimidazole derivatives in moderate to high yields. Remarkably, the procedure occurs exclusively in water and doesn’t require the use of any additional reagent/catalyst, rendering the methodology highly valuable from both environmental and economical points of view.

  10. Spectral intensities and bonding parameters for some praseodymium(III) and neodymium(III) complexes with benzimidazoles

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, P C; Ojha, C K; Mittal, S; Joshi, G K

    1988-09-01

    The electronic spectral intensity parameters (Judd-Ofelt; Tsub(lambda)) calculated from absorption spectral data for the complexes of praseodymium(III) and neodymium(III) nitrates with benzimidazole and 2-methyl-, 2-ethyl- and 2-n-propyl-benzimidazoles are reported. The conductance of these derivatives in dimethylformamide suggests 1:1 electrolytic nature. The infrared spectral data indicate the presence of Csub(2v) as well Dsub(2h)-nitrate ions in the complexes. The correlation of the intensity of hypersensitive transitions with bonding (nephelauxetic ratio and degree of covalency) parameters are also reported. (author). 13 refs., 2 tables.

  11. Cellular distribution, purification and electrophoretic properties of malate dehydrogenase in Trichuris ovis and inhibition by benzimidazoles and pyrimidine derivatives.

    Science.gov (United States)

    Sanchez-Moreno, M; Ortega, J E; Valero, A

    1989-12-01

    High levels of malate dehydrogenase were found in Trichuris ovis. Two molecular forms of the enzyme, of different cellular location and electrophoretic pattern, were isolated and purified. The activity of soluble malate dehydrogenase was greater than that of mitochondrial malate dehydrogenase. Both forms also displayed different electrophoretic profiles in comparison with purified extracts from goat (Capra hircus) liver. Substrate concentration directly affected enzyme activity. Host and parasite malate dehydrogenase activity were both inhibited by a series of benzimidazoles and pyrimidine-derived compounds, some of which markedly reduced parasite enzyme activity, but not host enzyme activity. Percentage inhibition by some pyrimidine derivatives was greater than that produced by benzimidazoles.

  12. Molecule Matters van der Waals Molecules

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 12. Molecule Matters van der Waals Molecules - Noble Gas Clusters are London Molecules! E Arunan. Feature Article Volume 14 Issue 12 December 2009 pp 1210-1222 ...

  13. Sorption-desorption characteristics of benzimidazole based fungicide 2-(4-fluorophenyl)-1h-benzimidazole on physicochemical properties of selected pakistani soils

    International Nuclear Information System (INIS)

    Ahmad, K.S.

    2014-01-01

    A batch equilibrium method has been utilized to investigate the sorption-desorption behavior of a versatile cost-effective fungicide2-(4-fluorophenyl)-1H-benzimidazole) FBNZ on four Pakistani soils geographically distant, from hilly to desert areas. FBNZ is a newly synthesized fungicide prepared in the laboratory and is cost effective than the commercially available fungicides. The adsorption and desorption data were fitted to the Freundlich equation, with values of na = 1, which points to a C-type isotherm. Sorption increases with soil organic carbon content, with greater degree of adsorption for hilly soil and least adsorption on sandy soil of Multan, Punjab. Desorption studies reveal that the adsorbed fungicide are firmly retained by soil particles and present a certain degree of irreversibility. The results indicate that the soil organic matters followed by clay content are the most important soil properties governing the fungicide sorption capacity. (author)

  14. Relationship of Resistance to Benzimidazole Fungicides with Mutation of β-Tubulin Gene in Venturia nashicola

    Directory of Open Access Journals (Sweden)

    Yeonsoo Kwak

    2017-06-01

    Full Text Available Pear scab caused by Venturia nashicola has been reported as an important disease of pear resulting in lowering the quality of pear fruits. In this study, it was conducted to investigate the relationship between resistance of V. nashicola and mutation of β-tubulin gene and the fungicide resistance in field isolate group in benzimidazole fungicides. Responce of V. nashicola to carbendazim could be classified into 3 groups as sensitive that does not grow at all on PDA amended with 0.16 μg/ml of carbendazim, low resistance that could not grow in 4.0 μg/ml medium, and high resistance that can grow even at 100 μg/ml. Thirty isolates of V. nashicola collected from 3 regions as Wonju, Naju, and Okcheon were highly resistant to carbendazim. Analysis of the nucleotide sequence of β-tubulin gene of V. nashicola showed that there was no difference in the nucleotide sequence between the sensitive and the low-resistant isolate, but GAG at codon 198 (glutamic acid was replaced with GCG (alanine in the high-resistant isolate. Among 10 isolates obtained from the Okcheon, 5 isolates showed the substitution of glycine for glutamic acid, which were resistant to carbendazim, but more sensitive to the mixture of carbendazim and diethofencarb than others. Through these results, all isolates of V. nashicola isolated in pear orchard were found to be resistant to benzimidazoles. Also, mutants E198A and E198G at β-tubulin were found to be important mechanisms of V. nashicola resistance against benzimidazole fungicides.

  15. (S-2-(2-Pyrrolidinio-1H-benzimidazol-3-ium dichloride monohydrate

    Directory of Open Access Journals (Sweden)

    Dai Jing

    2009-06-01

    Full Text Available In the title compound, C11H15N32+·2Cl−·H2O, one N atom of the imidazole ring and the N atom of the pyrrolidine ring are protonated. The crystal structure is stabilized by aromatic π–π interactions between the benzene rings of neighbouring benzimidazole systems [centroid–centroid duistance = 3.712 (2 Å]. The crystal structure is further stabilized by intermolecular N—H...Cl, O—H...Cl and N—H...O hydrogen bonds.

  16. Novel benzimidazole derivatives as phosphodiesterase 10A (PDE10A) inhibitors with improved metabolic stability.

    Science.gov (United States)

    Chino, Ayaka; Masuda, Naoyuki; Amano, Yasushi; Honbou, Kazuya; Mihara, Takuma; Yamazaki, Mayako; Tomishima, Masaki

    2014-07-01

    In this study, we report the identification of potent benzimidazoles as PDE10A inhibitors. We first identified imidazopyridine 1 as a high-throughput screening hit compound from an in-house library. Next, optimization of the imidazopyridine moiety to improve inhibitory activity gave imidazopyridinone 10b. Following further structure-activity relationship development by reducing lipophilicity and introducing substituents, we acquired 35, which exhibited both improved metabolic stability and reduced CYP3A4 time-dependent inhibition. Copyright © 2014. Published by Elsevier Ltd.

  17. Preparation and evaluation of some benzimidazole derivatives as antioxidants for local base oil

    Directory of Open Access Journals (Sweden)

    J.S. Basta

    2017-12-01

    Full Text Available Some benzimidazole derivatives, 2(1-H benzo(dimidazole-2-y1thio N-butyl acetamide Ia, 2(I-H benzo(dimidazole-2-ylthio N-octylacetamid Ib and 2(I-H benzo(dimidazole-2-yl thio N-dodecylactamide Ic were prepared and studied as antioxidants for base stock. The structure of these compounds was elucidated by elemental analysis, IR and 1H NMR spectroscopy. The inhibition efficiency of the prepared compounds was determined by studying the oxidation stability of the local base oil via the change in total acid number (TAN, viscosity and infrared (IR spectroscopy.

  18. Synthesis of (benzimidazol-2-yl)aniline derivatives as glycogen phosphorylase inhibitors.

    Science.gov (United States)

    Galal, Shadia A; Khattab, Muhammad; Andreadaki, Fotini; Chrysina, Evangelia D; Praly, Jean-Pierre; Ragab, Fatma A F; El Diwani, Hoda I

    2016-11-01

    A series of (benzimidazol-2-yl)-aniline (1) derivatives has been synthesized and evaluated as glycogen phosphorylase (GP) inhibitors. Kinetics studies revealed that compounds displaying a lateral heterocyclic residue with several heteroatoms (series 3 and 5) exhibited modest inhibitory properties with IC 50 values in the 400-600μM range. Arylsulfonyl derivatives 7 (Ar: phenyl) and 9 (Ar: o-nitrophenyl) of 1 exhibited the highest activity (series 2) among the studied compounds (IC 50 324μM and 357μM, respectively) with stronger effect than the p-tolyl analogue 8. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Complexes of molybdenum(III) with 2-(2'-pyridyl)benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, S P [Patna Univ. (India). Dept. of Chemistry; Prasad, K M [H.D. Jain Coll., Arrah (India). Dept. of Chemistry

    1979-07-01

    Molybdenum(III) forms with 2-(2'-pyridyl) benzimidazole(LH) the trischelated complexes, (Mo(LH)/sub 3/)X/sub 3/ as well as the cationic-anionic complexes, (Mo(LH)/sub 3/X/sub 2/)/sup +/ (Mo(LH)X/sub 4/)/sup -/(X=Cl/sup -/,Br/sup -/ or NCS/sup -/), depending on pH. These complexes have been synthesised and characterised from elemental analyses, i.r. and electronic spectra, magnetic moments and molar conductance.

  20. Quenching methods for background reduction in luminescence-based probe-target binding assays

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Hong [Los Alamos, NM; Goodwin, Peter M [Los Alamos, NM; Keller, Richard A [Los Alamos, NM; Nolan, Rhiannon L [Santa Fe, NM

    2007-04-10

    Background luminescence is reduced from a solution containing unbound luminescent probes, each having a first molecule that attaches to a target molecule and having an attached luminescent moiety, and luminescent probe/target adducts. Quenching capture reagent molecules are formed that are capable of forming an adduct with the unbound luminescent probes and having an attached quencher material effective to quench luminescence of the luminescent moiety. The quencher material of the capture reagent molecules is added to a solution of the luminescent probe/target adducts and binds in a proximity to the luminescent moiety of the unbound luminescent probes to quench luminescence from the luminescent moiety when the luminescent moiety is exposed to exciting illumination. The quencher capture reagent does not bind to probe molecules that are bound to target molecules and the probe/target adduct emission is not quenched.

  1. Probing the magnetic moments of [Mn{sup III}{sub 6}Cr{sup III}]{sup 3+} single-molecule magnets—A cross comparison of XMCD and spin-resolved electron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Helmstedt, Andreas, E-mail: helmstedt.andreas@gmail.com [Faculty of Physics, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld (Germany); Dohmeier, Niklas; Müller, Norbert; Gryzia, Aaron; Brechling, Armin; Heinzmann, Ulrich [Faculty of Physics, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld (Germany); Hoeke, Veronika; Krickemeyer, Erich; Glaser, Thorsten [Faculty of Chemistry, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld (Germany); Leicht, Philipp; Fonin, Mikhail [Fachbereich Physik, Universität Konstanz, Universitätsstr. 10, 78457 Konstanz (Germany); Tietze, Thomas [Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, 70569 Stuttgart (Germany); Joly, Loïc [Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, CNRS-Université de Strasbourg, BP 43, 23 rue du Loess, F-67034 Strasbourg Cedex 2 (France); Kuepper, Karsten [Institut für Festkörperphysik, Universität Ulm, 89069 Ulm (Germany)

    2015-01-15

    Highlights: • [Mn{sup III}{sub 6}Cr{sup III}]{sup 3+} single-molecule magnets are investigated. • XMCD and spin-resolved electron spectroscopy (SPES) results are compared. • A simple sum rule evaluation is performed for comparison. • Differences between SPES and XMCD results are discussed. • Influences of the magnetic field on the Mn L edge absorption are observed. - Abstract: Single-molecule magnets (SMM) of the [Mn{sup III}{sub 6}Cr{sup III}]{sup 3+} structural type prepared on Si and gold-coated glass substrates have been investigated by spin-resolved electron spectroscopy (SPES) and X-ray magnetic circular dichroism (XMCD) at the Mn L{sub 3,2} edge and in addition by XMCD at the Cr L{sub 3,2} edge using synchrotron radiation. Differences between the two methods are discussed. Despite its severe limitations for 3d transition metals, a spin sum rule evaluation is nevertheless performed for the Mn{sup III} centres in the [Mn{sup III}{sub 6}Cr{sup III}]{sup 3+} SMM to provide a simple means of comparing XMCD and spin-resolved electron spectroscopy results.

  2. An effective colorimetric and ratiometric fluorescent probe for bisulfite in aqueous solution

    International Nuclear Information System (INIS)

    Dai, Xi; Zhang, Tao; Du, Zhi-Fang; Cao, Xiang-Jian; Chen, Ming-Yu; Hu, Sheng-Wen; Miao, Jun-Ying; Zhao, Bao-Xiang

    2015-01-01

    We have developed the first two-photon colorimetric and ratiometric fluorescent probe, BICO, for the detection of bisulfite (HSO 3 − ) in aqueous solution. The probe contains coumarin and benzimidazole moieties and can detect HSO 3 − based on the Michael addition reaction with a limit of detection 5.3 × 10 −8  M in phosphate-buffered saline solution. The probe was used to detect bisulfite in tap water, sugar and dry white wine. Moreover, test strips were made and used easily. We successfully applied the probe to image living cells, using one-photon fluorescence imaging. BICO overcomes the limitations in sensitivity of previously reported probes and the solvation effect of bisulfite, which demonstrates its excellent value in practical application. - Highlights: • A colorimetric and ratiometric fluorescent probe was developed. • The probe could detect bisulfite in PBS buffer solution and real samples. • Bisulfite test paper was made to naked-eye detect bisulfite. • This probe successfully used to living cell imaging in ratiometric manner

  3. An effective colorimetric and ratiometric fluorescent probe for bisulfite in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Xi [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Zhang, Tao [Institute of Developmental Biology, School of Life Science, Shandong University, Jinan 250100 (China); Du, Zhi-Fang; Cao, Xiang-Jian; Chen, Ming-Yu [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Taishan College, Shandong University, Jinan 250100 (China); Hu, Sheng-Wen [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Miao, Jun-Ying, E-mail: miaojy@sdu.edu.cn [Institute of Developmental Biology, School of Life Science, Shandong University, Jinan 250100 (China); Zhao, Bao-Xiang, E-mail: bxzhao@sdu.edu.cn [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

    2015-08-12

    We have developed the first two-photon colorimetric and ratiometric fluorescent probe, BICO, for the detection of bisulfite (HSO{sub 3}{sup −}) in aqueous solution. The probe contains coumarin and benzimidazole moieties and can detect HSO{sub 3}{sup −} based on the Michael addition reaction with a limit of detection 5.3 × 10{sup −8} M in phosphate-buffered saline solution. The probe was used to detect bisulfite in tap water, sugar and dry white wine. Moreover, test strips were made and used easily. We successfully applied the probe to image living cells, using one-photon fluorescence imaging. BICO overcomes the limitations in sensitivity of previously reported probes and the solvation effect of bisulfite, which demonstrates its excellent value in practical application. - Highlights: • A colorimetric and ratiometric fluorescent probe was developed. • The probe could detect bisulfite in PBS buffer solution and real samples. • Bisulfite test paper was made to naked-eye detect bisulfite. • This probe successfully used to living cell imaging in ratiometric manner.

  4. Synthesis and properties of mixed-ligand ruthenium(II) complexes containing 2-(2-pyridyl)-benzimidazole and related ligands

    Energy Technology Data Exchange (ETDEWEB)

    Haga, M [Mie Univ., Tsu (Japan); Tanaka, T

    1979-07-01

    Mixed-ligand ruthenium(II) complexes of the (Ru(bpy)/sub 2/L)sup(n+) (ClO/sub 4/)sub(n) type, where bpy= 2,2'-bipyridine; L= 2-(2-pyridyl)-benzimidazole (PBImH) when n= 2, and L= 2-(2-pyridyl)-benzimidazolate (PBIm) and 2-(o-hydroxyphenyl)-benzimidazole (OBImH) when n= 1, were prepared. Anodic peak potentials and ruthenium-to-bipyridine charge transfer bands of these complexes are rationalized in terms of the donor ability of L.

  5. Synthesis and properties of mixed-ligand ruthenium(II) complexes containing 2-(2-pyridyl)-benzimidazole and related ligands

    International Nuclear Information System (INIS)

    Haga, Masaaki; Tanaka, Toshio.

    1979-01-01

    Mixed-ligand ruthenium(II) complexes of the [Ru(bpy) 2 L]sup(n+) (ClO 4 )sub(n) type, where bpy= 2,2'-bipyridine; L= 2-(2-pyridyl)-benzimidazole (PBImH) when n= 2, and L= 2-(2-pyridyl)-benzimidazolate (PBIm) and 2-(o-hydroxyphenyl)-benzimidazole (OBImH) when n= 1, were prepared. Anodic peak potentials and ruthenium-to-bipyridine charge transfer bands of these complexes are rationalized in terms of the donor ability of L. (author)

  6. Benzimidazole derivative small-molecule 991 enhances AMPK activity and glucose uptake induced by AICAR or contraction in skeletal muscle.

    Science.gov (United States)

    Bultot, Laurent; Jensen, Thomas E; Lai, Yu-Chiang; Madsen, Agnete L B; Collodet, Caterina; Kviklyte, Samanta; Deak, Maria; Yavari, Arash; Foretz, Marc; Ghaffari, Sahar; Bellahcene, Mohamed; Ashrafian, Houman; Rider, Mark H; Richter, Erik A; Sakamoto, Kei

    2016-10-01

    AMP-activated protein kinase (AMPK) plays diverse roles and coordinates complex metabolic pathways for maintenance of energy homeostasis. This could be explained by the fact that AMPK exists as multiple heterotrimer complexes comprising a catalytic α-subunit (α1 and α2) and regulatory β (β1 and β2)- and γ (γ1, γ2, γ3)-subunits, which are uniquely distributed across different cell types. There has been keen interest in developing specific and isoform-selective AMPK-activating drugs for therapeutic use and also as research tools. Moreover, establishing ways of enhancing cellular AMPK activity would be beneficial for both purposes. Here, we investigated if a recently described potent AMPK activator called 991, in combination with the commonly used activator 5-aminoimidazole-4-carboxamide riboside or contraction, further enhances AMPK activity and glucose transport in mouse skeletal muscle ex vivo. Given that the γ3-subunit is exclusively expressed in skeletal muscle and has been implicated in contraction-induced glucose transport, we measured the activity of AMPKγ3 as well as ubiquitously expressed γ1-containing complexes. We initially validated the specificity of the antibodies for the assessment of isoform-specific AMPK activity using AMPK-deficient mouse models. We observed that a low dose of 991 (5 μM) stimulated a modest or negligible activity of both γ1- and γ3-containing AMPK complexes. Strikingly, dual treatment with 991 and 5-aminoimidazole-4-carboxamide riboside or 991 and contraction profoundly enhanced AMPKγ1/γ3 complex activation and glucose transport compared with any of the single treatments. The study demonstrates the utility of a dual activator approach to achieve a greater activation of AMPK and downstream physiological responses in various cell types, including skeletal muscle. Copyright © 2016 the American Physiological Society.

  7. Benzimidazole derivative small-molecule 991 enhances AMPK activity and glucose uptake induced by AICAR or contraction in skeletal muscle

    DEFF Research Database (Denmark)

    Bultot, Laurent; Jensen, Thomas Elbenhardt; Lai, Yu-Chiang

    2016-01-01

    AMP-activated protein kinase (AMPK) plays diverse roles and coordinates complex metabolic pathways for maintenance of energy homeostasis. This could be explained by the fact that AMPK exists as multiple heterotrimer complexes comprising a catalytic α-subunit (α1 and α2) and regulatory β (β1 and β...

  8. Design, synthesis, molecular docking and biological evaluation of new dithiocarbamates substituted benzimidazole and chalcones as possible chemotherapeutic agents.

    Science.gov (United States)

    Bacharaju, Keerthana; Jambula, Swathi Reddy; Sivan, Sreekanth; Jyostnatangeda, Saritha; Manga, Vijjulatha

    2012-05-01

    A series of novel dithiocarbamates with benzimidazole and chalcone scaffold have been designed synthesised and evaluated for their antimitotic activity. Compounds 4c and 9d display the most promising antimitotic activity with IC(50) of 1.66 μM and 1.52 μM respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Synthesis of pyrido[1,2-a]benzimidazoles and other fused imidazole derivatives with a bridgehead nitrogen atom

    Science.gov (United States)

    Begunov, Roman S.; Ryzvanovich, Galina A.

    2013-01-01

    Main methods for the synthesis of fused imidazole derivatives with a bridgehead nitrogen atom are systematically considered and summarized. The reaction mechanisms that underlie the methods for the synthesis of pyrido[1,2-a]benzimidazoles and related compounds are described. Biological properties and mechanisms of the biological activity of fused azaheterocycles are discussed. The bibliography includes 152 references.

  10. An efficient solvent-free synthesis of imidazolines and benzimidazoles using K 4[Fe(CN 6] catalysis

    Directory of Open Access Journals (Sweden)

    Kabeer A. Shaikh

    2012-01-01

    Full Text Available Imidazolines and Benzimidazoles have been efficiently synthesized in high yields by treatment of 1,2-diamine with aldehydes using the metal co-ordinate complex K 4[Fe(CN 6] as a catalysis. The method was carried out under solvent free condition via oxidation of carbon-nitrogen bond. The process is green, mild and inexpensive.

  11. Synthesis and optical properties of novel pyrido[1,2-a]benzimidazole-containing 1,3,4-oxadiazole derivatives

    International Nuclear Information System (INIS)

    Yang He; Ge Yanqing; Jia Jiong; Wang Jianwu

    2011-01-01

    A series of novel substituted 1,3,4-oxadiazole derivatives containing pyrido[1,2-a]benzimidazole moiety were synthesized and characterized using FTIR, 1 H NMR, 13 C NMR, and HRMS. An efficient tandem reaction was employed as a key step in constructing the pyrido[1,2-a]benzimidazole moiety under very mild condition. The structure of compound 4a was established by X-ray crystallography. The UV-vis absorption and fluorescence spectral characteristics of these compounds were investigated in several solvents. Compounds 4a-i display similar absorptions, with absorption peaks ranging from 330 to 339 nm in acetonitrile, while the absorption maxima of compound 4j bearing a diphenylamino group on the benzene ring is red-shifted distinctly to 377 nm due to the strong electron-donating property of its substituent and extended π-conjugated system. All these target heterocyclic compounds present blue-green emissions (461-487 nm) in dilute solutions and show high quantum yields of fluorescence (φ PL =0.65-0.99) in dichloromethane. - Research Highlights: → The first report about the unique optical properties of pyrido[1,2-a]benzimidazole heteroaromatic compounds containing 1,3,4-oxadiazole unit. → Synthesis of pyrido[1,2-a]benzimidazole moiety via a novel efficient tandem reaction. → The target heterocyclic compounds showing high quantum yields of fluorescence, with great potential for use as fluorescent pigments and in optical/electro devices.

  12. Synthesis of amino ester-embedded benzimidazoles: a one-pot sequential protocol under metal-free neutral conditions.

    Science.gov (United States)

    Roy, Priyabrata; Bodhak, Chandan; Pramanik, Animesh

    2017-02-01

    A one-pot three-component protocol has been developed for the synthesis of amino ester-embedded benzimidazoles under metal-free neutral conditions. Sequentially, the methodology involves coupling of an amino ester with 1-fluoro-2-nitrobenzene, reduction of the coupled nitroarene by sodium dithionite, and cyclization of the corresponding diamine with an aldehyde.

  13. Cancer stem cells CD133 inhibition and cytotoxicity of certain 3-phenylthiazolo[3,2-a]benzimidazoles: design, direct synthesis, crystal study and in vitro biological evaluation.

    Science.gov (United States)

    Al-Ansary, Ghada H; Eldehna, Wagdy M; Ghabbour, Hazem A; Al-Rashood, Sara T A; Al-Rashood, Khalid A; Eladwy, Radwa A; Al-Dhfyan, Abdullah; Kabil, Maha M; Abdel-Aziz, Hatem A

    2017-12-01

    Cancer stem cells (CSCs) have been objects of intensive study since their identification in 1994. Adopting a structural rigidification approach, a novel series of 3-phenylthiazolo[3,2-a]benzimidazoles 4a-d was designed and synthesised, in an attempt to develop potent anticancer agent that can target the bulk of tumour cells and CSCs. The anti-proliferative activity of the synthesised compounds was evaluated against two cell lines, namely; colon cancer HT-29 and triple negative breast cancer MDA-MB-468 cell lines. Also, their inhibitory activity against the cell surface expression of CD133 was examined. In particular, compound 4b emerged as a promising hit molecule as it manifested good antineoplastic potency against both tested cell lines (IC 50  = 9 and 12 μM, respectively), beside its ability to inhibit the cell surface expression of CD133 by 50% suggesting a promising potential of effectively controlling the tumour by eradicating the tumour bulk and inhibiting the proliferation of the CSCs. Moreover, compounds 4a and 4c showed moderate activity against HT-29 (IC 50  = 21 and 29 μM, respectively) and MDA-MB-468 (IC 50  = 23 and 24 μM, respectively) cell lines, while they inhibited the CD133 expression by 14% and 48%, respectively. Finally, a single crystal X-ray diffraction was recorded for compound 4d.

  14. Fragment-based design of symmetrical bis-benzimidazoles as selective inhibitors of the trimethoprim-resistant, type II R67 dihydrofolate reductase.

    Science.gov (United States)

    Bastien, Dominic; Ebert, Maximilian C C J C; Forge, Delphine; Toulouse, Jacynthe; Kadnikova, Natalia; Perron, Florent; Mayence, Annie; Huang, Tien L; Vanden Eynde, Jean Jacques; Pelletier, Joelle N

    2012-04-12

    The continuously increasing use of trimethoprim as a common antibiotic for medical use and for prophylactic application in terrestrial and aquatic animal farming has increased its prevalence in the environment. This has been accompanied by increased drug resistance, generally in the form of alterations in the drug target, dihydrofolate reductase (DHFR). The most highly resistant variants of DHFR are known as type II DHFR, among which R67 DHFR is the most broadly studied variant. We report the first attempt at designing specific inhibitors to this emerging drug target by fragment-based design. The detection of inhibition in R67 DHFR was accompanied by parallel monitoring of the human DHFR, as an assessment of compound selectivity. By those means, small aromatic molecules of 150-250 g/mol (fragments) inhibiting R67 DHFR selectively in the low millimolar range were identified. More complex, symmetrical bis-benzimidazoles and a bis-carboxyphenyl were then assayed as fragment-based leads, which procured selective inhibition of the target in the low micromolar range (K(i) = 2-4 μM). The putative mode of inhibition is discussed according to molecular modeling supported by in vitro tests. © 2012 American Chemical Society

  15. Silane Cross-Linked Sulfonted Poly(Ether Ketone/Ether Benzimidazoles for Fuel Cell Applications

    Directory of Open Access Journals (Sweden)

    Zilu Yao

    2017-11-01

    Full Text Available γ-(2,3-epoxypropoxy propyltrimethoxysilane (KH-560 was incorporated in various proportions into side-chain-type sulfonated poly(ether ketone/ether benzimidazole (SPEKEBI as a crosslinker, to make membranes with high ion exchange capacities and excellent performance for direct methanol fuel cells (DMFCs. Systematical measurements including Fourier transform infrared (FT-IR, scanning electron microscopy-energy-dispersive and X-ray photoelectron spectroscopy (XPS proved the complete disappearance of epoxy groups in KH-560 and the existence of Si in the membranes. The resulting membranes showed increased mechanical strength and thermal stability compared to the unmodified sulfonated poly(ether ketone/ether benzimidazole membrane in appropriate doping amount. Meanwhile, the methanol permeability has decreased, leading to the increase of relative selectivities of SPEKEBI-x-SiO2 membranes. Furthermore, the H2/O2 cell performance of SPEKEBI-2.5-SiO2 membrane showed a much higher peak power density compared with the pure SPEKEBI memrbrane.

  16. Structure of eight molecular salts assembled from noncovalent bonding between carboxylic acids, imidazole, and benzimidazole

    Science.gov (United States)

    Jin, Shouwen; Zhang, Huan; Liu, Hui; Wen, Xianhong; Li, Minghui; Wang, Daqi

    2015-09-01

    Eight organic salts of imidazole/benzimidazole have been prepared with carboxylic acids as 2-methyl-2-phenoxypropanoic acid, α-ketoglutaric acid, 5-nitrosalicylic acid, isophthalic acid, 4-nitro-phthalic acid, and 3,5-dinitrosalicylic acid. The eight crystalline forms reported are proton-transfer compounds of which the crystals and compounds were characterized by X-ray diffraction analysis, IR, mp, and elemental analysis. These structures adopted hetero supramolecular synthons, with the most common R22(7) motif observed at salts 2, 3, 5, 6 and 8. Analysis of the crystal packing of 1-8 suggests that there are extensive strong Nsbnd H⋯O, and Osbnd H⋯O hydrogen bonds (charge assisted or neutral) between acid and imidazolyl components in all of the salts. Except the classical hydrogen bonding interactions, the secondary propagating interactions also play important roles in structure extension. This variety, coupled with the varying geometries and number of acidic groups of the acids utilized, has led to the creation of eight supramolecular arrays with 1D-3D structure. The role of weak and strong noncovalent interactions in the crystal packing is analyzed. The results presented herein indicate that the strength and directionality of the Nsbnd H⋯O, and Osbnd H⋯O hydrogen bonds between acids and imidazole/benzimidazole are sufficient to bring about the formation of organic salts.

  17. Microwave-assisted Synthesis of Benzimidazole Derivatives from Citronellal in Kaffir Lime (Citrus hystrix DC.) Oil

    Science.gov (United States)

    Sapri Ramadhan, Dwi; Warsito; Dhiaul Iftitah, Elvina

    2018-01-01

    Benzimidazoles are an important group of heterocyclic aromatic organic compound in the field of medicinal chemistry. It plays a very important role in pharmacological activity such as, analgesic, antiinflammatory, antibacterial, anti ungal, anti iral, antithelmenthic, anti convulsant, antihypertensive, and antiulcer. The synthesis of benzimidazole derivative under microwave irradiation of citronellal as raw material which is extracted from Citrus hystrix DC. (kaffir lime) leaves. The reaction using methanol and dichloromethane as solvent with variation of reaction time at 30, 40, 50, 60, and 70 minutes and mole ratio of citronellal to 1,2-phenylenediamine, 1:1, 1:1.5, and 1:2, respectively. Synthesis products was characterized by FT-IR and GC-MS. The optimum reaction time was obtained at 60 minutes in the present of dichloromethane and 1:2 mole ratio of citronellal to 1,2-phenylenediamine. The yield of the product is 42.19%. Structure of the synthesized compound were assigned on spectrum bands for C=N str at 1661 cm-1, C-N str at 1271 cm-1, C=C str of benzene ring at 1622 and 1456 cm-1 and C=C str of alkene at 1379 cm-1. GC-MS analysis showed single peak with retention time of 15.339 minute and m/z 242.

  18. Adsorption and desorption characteristic of benzimidazole based fungicide carbendazim in pakistani soils

    International Nuclear Information System (INIS)

    Ahmad, K.S.; Rashid, N.; Tazaiyen, S.; Nazar, M.F.

    2013-01-01

    A versatile cost-effective Benzimidazole based fungicide, Carbendazim (methyl 1H-benzimidazole-2 carboxylate ) has been utilized to investigate its sorption-desorption behaviour on physicochemical properties of geographical soils, ranging from hilly to desert areas of Pakistan, via batch equilibrium method. The data obtained in all tests showed that adsorption co-efficient isotherm for Carbendazim in four tested soil were well fitted the freundlich equation. Distribution co-efficient (K d ) parameters are low (3.59 to 11.60 ml micro g/sup -1/) indicating low adsorption. It was observed that Carbendazim showed a relatively greater degree of adsorption on soil samples (Soil 4) that were collected from northern hilly areas Ayubia, Khyber Pakhton khaw (KPK) (Silt loam) i.e.11.60 ml mu g/sup -1/ and least adsorption on sandy Soil of Multan Punjab(Soil 2). While other two soils 1 were collected from Murree region, a boarder of Punjab and KPK mountain area and Soil 3 from Tarnol, Islamabad. Desorption studies reveal that the adsorbed fungicide is firmly retained by soil particles and their adsorption are almost irreversible. The results indicate that soil organic matter (SOM) and appropriate pH also play key role in sorption capacity. (author)

  19. QSAR study of benzimidazole derivatives inhibition on escherichia coli methionine Aminopeptidase

    Directory of Open Access Journals (Sweden)

    Zahra Garkani-Nejad

    2010-06-01

    Full Text Available The paper describes a quantitative structure-activity relationship (QSAR study of IC50 values of benzimidazole derivatives on escherichia coli methionine aminopeptidase. The activity of the 32 inhibitors has been estimated by means of multiple linear regression (MLR and artificial neural network (ANN techniques. The results obtained using the MLR method indicate that the activity of derivatives of benzimidazoles on CoII-loaded escherichia coli methionine aminopeptidase depend on different parameters containing topological descriptors, Burden eigen values, 3D MoRSE descriptors and 2D autocorrelation descriptors. The best artificial neural network model is a fully-connected, feed forward back propagation network with a 5-4-1 architecture. Standard error for the training set using this network was 0.193 with correlation coefficient 0.996 and for the prediction set standard error was 1.41 with correlation coefficient 0.802. Comparison of the quality of the ANN with different MLR models showed that ANN has a better predictive power.

  20. Design and Synthesis of Benzimidazoles As Novel Corticotropin-Releasing Factor 1 Receptor Antagonists.

    Science.gov (United States)

    Mochizuki, Michiyo; Kori, Masakuni; Kobayashi, Katsumi; Yano, Takahiko; Sako, Yuu; Tanaka, Maiko; Kanzaki, Naoyuki; Gyorkos, Albert C; Corrette, Christopher P; Cho, Suk Young; Pratt, Scott A; Aso, Kazuyoshi

    2016-03-24

    Benzazole derivatives with a flexible aryl group bonded through a one-atom linker as a new scaffold for a corticotropin-releasing factor 1 (CRF1) receptor antagonist were designed, synthesized, and evaluated. We expected that structural diversity could be expanded beyond that of reported CRF1 receptor antagonists. In a structure-activity relationship study, 4-chloro-N(2)-(4-chloro-2-methoxy-6-methylphenyl)-1-methyl-N(7),N(7)-dipropyl-1H-benzimidazole-2,7-diamine 29g had the most potent binding activity against a human CRF1 receptor and the antagonistic activity (IC50 = 9.5 and 88 nM, respectively) without concerns regarding cytotoxicity at 30 μM. Potent CRF1 receptor-binding activity in brain in an ex vivo test and suppression of stress-induced activation of the hypothalamus-pituitary-adrenocortical (HPA) axis were also observed at 138 μmol/kg of compound 29g after oral administration in mice. Thus, the newly designed benzimidazole 29g showed in vivo CRF1 receptor antagonistic activity and good brain penetration, indicating that it is a promising lead for CRF1 receptor antagonist drug discovery research.

  1. Recent advances in developing small molecules targeting RNA.

    Science.gov (United States)

    Guan, Lirui; Disney, Matthew D

    2012-01-20

    RNAs are underexploited targets for small molecule drugs or chemical probes of function. This may be due, in part, to a fundamental lack of understanding of the types of small molecules that bind RNA specifically and the types of RNA motifs that specifically bind small molecules. In this review, we describe recent advances in the development and design of small molecules that bind to RNA and modulate function that aim to fill this void.

  2. Application of a Reverse Line Blot hybridisation assay for the species-specific identification of cyathostomins (Nematoda, Strongylida) from benzimidazole-treated horses in the Slovak Republic.

    Science.gov (United States)

    Cernanská, Dana; Paoletti, Barbara; Králová-Hromadová, Ivica; Iorio, Raffaella; Cudeková, Patrícia; Milillo, Piermarino; Traversa, Donato

    2009-03-09

    Five horse farms located in eastern Slovakia were investigated for the presence of benzimidazole-resistant strongyles by faecal egg count reduction test and egg hatch assay. Coprocultures were prepared for each farm from faecal samples taken pre- and post-treatment and harvested larvae were molecularly examined with a Reverse Line Blot assay. Faecal egg count reduction values ranged from 0 to 52.5% and all farms were positive for benzimidazole-resistant cyathostomins. Seven benzimidazole-resistant cyathostomin species were molecularly identified on farms before and also after treatment. These data demonstrate that resistance to benzimidazoles is well established in cyathostomin populations from horse farms in the Slovak Republic and that the molecular assay was able to determine the species-specific distribution of resistant cyathostomins under field conditions.

  3. The Synthesis and Biological Evaluation of N-Substituted 1H-Benzimidazol-2-yl-1H-pyrazole-3,5-diamines

    Czech Academy of Sciences Publication Activity Database

    Jedinák, L.; Kryštof, Vladimír; Cankař, P.

    2016-01-01

    Roč. 53, č. 2 (2016), s. 499-507 ISSN 0022-152X Institutional support: RVO:61389030 Keywords : ONE-POT SYNTHESIS * BENZIMIDAZOLE DERIVATIVES * EFFICIENT SYNTHESIS Subject RIV: CE - Biochemistry Impact factor: 0.893, year: 2016

  4. A concise synthesis of benzimidazoles via the microwave-assisted one-pot batch reaction of amino acids up to a 10-g scale.

    Science.gov (United States)

    Peng, Pai; Xiong, Jin-Feng; Mo, Guang-Zhen; Zheng, Jia-Li; Chen, Ren-Hong; Chen, Xiao-Yun; Wang, Zhao-Yang

    2014-10-01

    An efficient method for the synthesis of aminomethyl benzimidazoles is developed by using a one-pot batch reaction between amino acids and o-phenylenediamines. This reaction proceeds smoothly in an unmodified household microwave oven, even though scale-up is to 10 g. A desirable method for the quick synthesis of benzimidazoles, which are used as a kind of important intermediates in drug synthesis, is provided by the scale-up utilization of amino acid resource.

  5. In vitro susceptibilities of the AIDS-associated microsporidian Encephalitozoon intestinalis to albendazole, its sulfoxide metabolite, and 12 additional benzimidazole derivatives.

    OpenAIRE

    Katiyar, S K; Edlind, T D

    1997-01-01

    Recent reports have described the successful treatment of Encephalitozoon intestinalis infection in AIDS patients with albendazole. However, this compound is rapidly metabolized in vivo to albendazole sulfoxide, and furthermore it is only 1 of about 15 commercially developed benzimidazole derivatives. To compare the activities of albendazole, albendazole sulfoxide, and other benzimidazoles, an in vitro system involving infection of green monkey kidney cell (E6) monolayers with E. intestinalis...

  6. Nanomaterials and MRI molecular probe

    International Nuclear Information System (INIS)

    Inubushi, Toshiro

    2008-01-01

    This paper presents the current state and future prospect of enhancing probes in MRI which enable to image specific cells and molecules mainly from the aspect of cell trafficking. Although MRI requires such probes for specific imaging, it has an advantage that anatomical images are simultaneously available even during surgical operation without radiation exposure, differing from X-CT, -transillumination and positron emission tomography (PET). In the development of novel MRI molecular probes, the recent topic concerns the cell trafficking biology where cells related with transplantation and immunological therapy can be traced. Although superparamagnetic iron oxide (SPIO) has been used as a commercially available enhancer, this nanoparticle has problems like a difficulty to penetrate cell, cytotoxicity and others. For these, authors have developed the nanoparticle SPIO covered with silica shell, which can be chemically modified, e.g., by binding fluorescent pigments to possibly allow MR bimodal molecular imaging. For penetration of particles in cells, envelop of Sendai virus is used. PET-CT has been more popular these days; however, MRI is superior to CT for imaging soft tissues, and development of PET-MRI is actively under progress aiming the multi-modal imaging. At present, molecular probes for MRI are certainly not so many as those for PET and cooperative efforts to develop the probes are required in medical, technological and pharmaceutical fields. (R.T.)

  7. Aligning molecules with intense nonresonant laser fields

    DEFF Research Database (Denmark)

    Larsen, J.J.; Safvan, C.P.; Sakai, H.

    1999-01-01

    Molecules in a seeded supersonic beam are aligned by the interaction between an intense nonresonant linearly polarized laser field and the molecular polarizability. We demonstrate the general applicability of the scheme by aligning I2, ICl, CS2, CH3I, and C6H5I molecules. The alignment is probed...... by mass selective two dimensional imaging of the photofragment ions produced by femtosecond laser pulses. Calculations on the degree of alignment of I2 are in good agreement with the experiments. We discuss some future applications of laser aligned molecules....

  8. Crystal structures of eight 3D molecular adducts derived from bis-imidazole, bis(benzimidazole), and organic acids

    Science.gov (United States)

    Ding, Aihua; Jin, Shouwen; Jin, Shide; Hu, KaiKai; Lin, Zhihao; Liu, Hui; Wang, Daqi

    2018-01-01

    Cocrystallization of the bis(imidazole)/bis(benzimidazole) with a series of organic acids gave a total of eight molecular adducts with the compositions: (3,6-bis(imidazole-1-yl)pyridazine): (trichloroacetic acid)2(1) [(H2L1)2+ · (tca-)2, L1 = 3,6-bis(imidazole-1-yl)pyridazine, tca- = trichloroacetate], (bis(N-imidazolyl)methane): (suberic acid) (2) [(L2) · (H2suba), L2 = bis(N-imidazolyl)methane, H2suba = suberic acid], bis(N-imidazolyl)methane: (3-nitrophthalic acid): 3H2O (3) [(H2L2)2+ · (3-Hnpa-)2 · 3H2O, 3-Hnpa- = 3-nitro hydrogenphthalate], (bis(N-imidazolyl)butane)0.5: (4-nitrophthalic acid): H2O (4) [(H2L3)0.5+ · (4-Hnpa-)- · H2O, L3 = bis(N-imidazolyl)butane, 4-Hnpa- = 4-nitro hydrogenphthalate], (1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole): (3,5-dinitrosalicylic acid) (5) [(HL4) · (3,5-dns-), L4 = 1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole, 3,5-dns- = 3,5-dinitrosalicylate], (1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole): (3-nitrophthalic acid) (6) [(H2L4) · (3-npa2-), L4 = 1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole, 3-npa2-=3-nitrogenphthalate], (bis(N-imidazolyl)butane): (pamoic acid) (7) [(H2L3) · (pam), pam = pamoate], and (3,6-bis(imidazole-1-yl)pyridazine): (1,5-naphthalenedisulfonic acid) [(H2L1)2+ · (npda)2- = 1,5-naphthalenedisulfonate] (8). The eight adducts have been characterized by X-ray diffraction technique, infrared spectrum, and elemental analysis, and the melting points of all adducts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the eight investigated crystals both the end ring N in the bis(imidazole) moieties are protonated when the organic acids are deprotonated except 2, and 5, and the crystal packing is interpreted in terms of the strong ionic Nsbnd H⋯O H-bond between the imidazolium and the deprotonated acidic groups. Except the Nsbnd H⋯O H-bond, the Osbnd H⋯O H-bonds were also found at the salts 3, 4

  9. Single-molecule dynamics in nanofabricated traps

    Science.gov (United States)

    Cohen, Adam

    2009-03-01

    The Anti-Brownian Electrokinetic trap (ABEL trap) provides a means to immobilize a single fluorescent molecule in solution, without surface attachment chemistry. The ABEL trap works by tracking the Brownian motion of a single molecule, and applying feedback electric fields to induce an electrokinetic motion that approximately cancels the Brownian motion. We present a new design for the ABEL trap that allows smaller molecules to be trapped and more information to be extracted from the dynamics of a single molecule than was previously possible. In particular, we present strategies for extracting dynamically fluctuating mobilities and diffusion coefficients, as a means to probe dynamic changes in molecular charge and shape. If one trapped molecule is good, many trapped molecules are better. An array of single molecules in solution, each immobilized without surface attachment chemistry, provides an ideal test-bed for single-molecule analyses of intramolecular dynamics and intermolecular interactions. We present a technology for creating such an array, using a fused silica plate with nanofabricated dimples and a removable cover for sealing single molecules within the dimples. With this device one can watch the shape fluctuations of single molecules of DNA or study cooperative interactions in weakly associating protein complexes.

  10. Molecule Matters van der Waals Molecules

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 7. Molecule Matters van der Waals Molecules - Rg•••HF Complexes are Debye Molecules! E Arunan. Feature Article Volume 15 Issue 7 July 2010 pp 667-674. Fulltext. Click here to view fulltext PDF. Permanent link:

  11. Observing electron motion in molecules

    International Nuclear Information System (INIS)

    Chelkowski, S; Yudin, G L; Bandrauk, A D

    2006-01-01

    We study analytically the possibility for monitoring electron motion in a molecule using two ultrashort laser pulses. The first prepares a coherent superposition of two electronic molecular states whereas the second (attosecond pulse) photoionizes the molecule. We show that interesting information about electron dynamics can be obtained from measurement of the photoelectron spectra as a function of the time delay between two pulses. In particular, asymmetries in photoelectron angular distribution provide a simple signature of the electron motion within the initial time-dependent coherently coupled two molecular states. Both asymmetries and electron spectra show very strong two-centre interference patterns. We illustrate these effects using as an example a dissociating hydrogen molecular ion probed by the attosecond pulses

  12. (2-Benzoyl-1-phenylethenolato-κ2O,O′bis[2-(1-phenyl-1H-benzimidazol-2-ylphenyl-κC1]iridium(III dichloromethane disolvate

    Directory of Open Access Journals (Sweden)

    Stanislav I. Bezzubov

    2016-12-01

    Full Text Available We present here synthesis and crystal structure of a neutral IrIII complex, [Ir(C19H13N22(C15H11O2]·2CH2Cl2 or [Ir(C^N2O^O]·2CH2Cl2, where C^N is 1,2-diphenyl-1H-benzimidazole and O^O is 2-benzoyl-1-phenylethenolate. The coordination sphere of the IrIII atom, located on a twofold rotation axis, is that of a slighlty distorted C2N2O2 octahedron, with the N atoms in a trans configuration. In the crystal, complex molecules assemble through weak C—H...π interactions in the range 2.699 (3–2.892 (3 Å. The solvent CH2Cl2 molecules reside in channels aligned along the a axis and are connected to the complex molecules by C—H...O interactions.

  13. Amine-free melanin-concentrating hormone receptor 1 antagonists: Novel 1-(1H-benzimidazol-6-yl)pyridin-2(1H)-one derivatives and design to avoid CYP3A4 time-dependent inhibition.

    Science.gov (United States)

    Igawa, Hideyuki; Takahashi, Masashi; Shirasaki, Mikio; Kakegawa, Keiko; Kina, Asato; Ikoma, Minoru; Aida, Jumpei; Yasuma, Tsuneo; Okuda, Shoki; Kawata, Yayoi; Noguchi, Toshihiro; Yamamoto, Syunsuke; Fujioka, Yasushi; Kundu, Mrinalkanti; Khamrai, Uttam; Nakayama, Masaharu; Nagisa, Yasutaka; Kasai, Shizuo; Maekawa, Tsuyoshi

    2016-06-01

    Melanin-concentrating hormone (MCH) is an attractive target for antiobesity agents, and numerous drug discovery programs are dedicated to finding small-molecule MCH receptor 1 (MCHR1) antagonists. We recently reported novel pyridine-2(1H)-ones as aliphatic amine-free MCHR1 antagonists that structurally featured an imidazo[1,2-a]pyridine-based bicyclic motif. To investigate imidazopyridine variants with lower basicity and less potential to inhibit cytochrome P450 3A4 (CYP3A4), we designed pyridine-2(1H)-ones bearing various less basic bicyclic motifs. Among these, a lead compound 6a bearing a 1H-benzimidazole motif showed comparable binding affinity to MCHR1 to the corresponding imidazopyridine derivative 1. Optimization of 6a afforded a series of potent thiophene derivatives (6q-u); however, most of these were found to cause time-dependent inhibition (TDI) of CYP3A4. As bioactivation of thiophenes to form sulfoxide or epoxide species was considered to be a major cause of CYP3A4 TDI, we introduced electron withdrawing groups on the thiophene and found that a CF3 group on the ring or a Cl adjacent to the sulfur atom helped prevent CYP3A4 TDI. Consequently, 4-[(5-chlorothiophen-2-yl)methoxy]-1-(2-cyclopropyl-1-methyl-1H-benzimidazol-6-yl)pyridin-2(1H)-one (6s) was identified as a potent MCHR1 antagonist without the risk of CYP3A4 TDI, which exhibited a promising safety profile including low CYP3A4 inhibition and exerted significant antiobesity effects in diet-induced obese F344 rats. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Efficient fluorescent deep-blue and hybrid white emitting devices based on carbazole/benzimidazole compound

    KAUST Repository

    Yang, Xiaohui

    2011-07-28

    We report the synthesis, photophysics, and electrochemical characterization of carbazole/benzimidazole-based compound (Cz-2pbb) and efficient fluorescent deep-blue light emitting devices based on Cz-2pbb with the peak external quantum efficiency of 4.1% and Commission Internationale dÉnclairage coordinates of (0.16, 0.05). Efficient deep-blue emission as well as high triplet state energy of Cz-2pbb enables fabrication of hybrid white organic light emitting diodes with a single emissive layer. Hybrid white emitting devices based on Cz-2pbb show the peak external quantum efficiency exceeding 10% and power efficiency of 14.8 lm/W at a luminance of 500 cd/m2. © 2011 American Chemical Society.

  15. Synthesis and Anti-inflammatory Evaluation of Novel Benzimidazole and Imidazopyridine Derivatives.

    Science.gov (United States)

    Chen, Gaozhi; Liu, Zhiguo; Zhang, Yali; Shan, Xiaoou; Jiang, Lili; Zhao, Yunjie; He, Wenfei; Feng, Zhiguo; Yang, Shulin; Liang, Guang

    2013-01-10

    Sepsis, an acute inflammatory disease, remains the most common cause of death in intensive care units. A series of benzimidazole and imidazopyridine derivatives were synthesized and screened for anti-inflammatory activities, and the imidazopyridine series showed excellent inhibition of the expression of inflammatory cytokines in LPS-stimulated macrophages. Compounds X10, X12, X13, X14, and X15 inhibited TNF-α and IL-6 release in a dose-dependent manner, and X12 showed no cytotoxicity in hepatic cells. Furthermore, X12 exhibited a significant protection against LPS-induced septic death in mouse models. Together, these data present a series of new imidazopyridines with potential therapeutic effects in acute inflammatory diseases.

  16. Direct Synthesis of 7 nm Thick Zinc(II)-Benzimidazole-Acetate Metal-Organic Framework Nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Feng; Kumar, Prashant; Xu, Wenqian; Mkhoyan, K. Andre; Tsapatsis, Michael

    2018-01-09

    Two-dimensional metal-organic frameworks (MOFs) are promising candidates for high performance gas sepa-ration membranes. Currently, MOF nanosheets are mostly fabricated through delamination of layered MOFs, which often re-sults in a low yield of intact free-standing nanosheets. In this work, we present a direct synthesis method for zinc(II)-benzimidazole-acetate (Zn(Bim)OAc) MOF nanosheets. The obtained nanosheets have a lateral dimension of 600 nm when synthesized at room temperature. By adjusting the synthesis temperature, the morphology of obtained nanosheets can be readily tuned from nanosheets to nanobelts. A thickness of 7 nm is determined for Zn(Bim)OAc using high-angle annular dark-field scanning transmission electron microscopy, which makes these nanosheets promising building blocks of gas sepa-ration membranes.

  17. Benzimidazole derivatives: search for GI-friendly anti-inflammatory analgesic agents

    Directory of Open Access Journals (Sweden)

    Monika Gaba

    2015-07-01

    Full Text Available Non-steroidal anti-inflammatory drugs (NSAIDs have been successfully used for the alleviation of pain and inflammation in the past and continue to be used daily by millions of patients worldwide. However, gastrointestinal (GI toxicity associated with NSAIDs is an important medical and socioeconomic problem. Local generation of various reactive oxygen species plays a significant role in the formation of gastric ulceration associated with NSAIDs therapy. Co-medication of antioxidants along with NSAIDs has been found to be beneficial in the prevention of GI injury. This paper describes the synthesis and biological evaluation of N-1-(phenylsulfonyl-2-methylamino-substituted-1H-benzimidazole derivatives as anti-inflammatory analgesic agents with lower GI toxicity. Studies in vitro and in vivo demonstrated that the antioxidant activity of the test compounds decreased GI toxicity.

  18. Solubility improvement of an anthelmintic benzimidazole carbamate by association with dendrimers

    Directory of Open Access Journals (Sweden)

    L. Fernández

    2011-12-01

    Full Text Available The improvement of aqueous solubility of methyl (5-[propylthio]-1H-benzimidazol-2-yl carbamate, albendazole (ABZ using polyamidoamine (PAMAM dendrimers as solubility enhancers was investigated. Full generation PAMAM dendrimers with amine terminal groups, (G3, with hydroxyl terminal groups (G3OH and half generation PAMAM dendrimers with carboxylate terminal groups (G2.5 and G3.5, were chosen for this study. The nature of dendrimer-ABZ association was investigated by UV absorption, fluorescence emission measurements and by ¹H-NMR spectroscopy. The results obtained show that these polymeric structures have the capacity to enhance the solubility of ABZ, both lipophilic and specific hydrogen bond interactions contributing to the guest-host association. Although all studied dendrimers have hydrophobic internal nanoenvironments with similar dimensions, their surfaces differ significantly and the nature and the localization of the interactions involved in ABZ-dendrimer association depend on the type of terminal groups.

  19. Nonpeptidic angiotensin II AT₁ receptor antagonists derived from 6-substituted aminocarbonyl and acylamino benzimidazoles.

    Science.gov (United States)

    Zhang, Jun; Wang, Jin-Liang; Yu, Wei-Fa; Zhou, Zhi-Ming; Tao, Wen-Chang; Wang, Yi-Cheng; Xue, Wei-Zhe; Xu, Di; Hao, Li-Ping; Han, Xiao-Feng; Fei, Fan; Liu, Ting; Liang, Ai-Hua

    2013-11-01

    Both 6-substituted aminocarbonyl and acylamino benzimidazole derivatives were designed and synthesized as nonpeptidic angiotensin II AT₁ receptor antagonists. Compounds 6f, 6g, 11e, 11f, 11g, and 12 showed nanomolar AT₁ receptor binding affinity and high AT₁ receptor selectivity over AT₂ receptor in a preliminary pharmacological evaluation. Among them, the two most active compounds 6f (AT₁ IC₅₀ = 3 nM, AT₂ IC₅₀ > 10,000 nM, PA₂ = 8.51) and 11g (AT₁ IC₅₀ = 0.1 nM, AT₂ IC₅₀ = 149 nM, PA₂ = 8.43) exhibited good antagonistic activity in isolated rabbit aortic strip functional assay. In addition, they were orally active AT₁ receptor antagonists in spontaneous hypertensive rats. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. Microwave assisted synthesis and anti-lipase activity of some new fluorine-containing benzimidazoles.

    Science.gov (United States)

    Menteşe, E; Yilmaz, F; Ülker, S; Kahveci, B

    2015-01-01

    In this study, a new series of fluorine containing benzimidazoles (4a-l) and bisbenzimidazoles (6a-c, 8) were synthesized by the reaction of o-phenylenediamines with iminoester hydrochlorides (3a-l, 7) in methanol under microwave irradiation. The structures of these newly synthesized compounds were identified by IR, (1)H-NMR, (13)C-NMR, mass spectroscopy and elemental analysis data. The synthesized compounds were screened for their pancreatic lipase activities. Our results indicate that the compounds 6a, 6b and 6c can serve as an anti-lipase agent. The compounds 6b and 6c inhibited pancreatic lipase activity by 84.03% and 97.49% at a concentration of 3 µg/mL, respectively. © Georg Thieme Verlag KG Stuttgart · New York.

  1. A general method for tritium labelling of benzimidazole carbamates by catalytic exchange in dioxane solutions

    Energy Technology Data Exchange (ETDEWEB)

    Lacey, E [Commonwealth Scientific and Industrial Research Organization, Glebe, NSW (Australia). Div. of Animal Health, McMaster Lab.; Dawson, M [Sydney Univ. (Australia). Dept. of Pharmacy; Long, M A; Than, C [New South Wales Univ., Kensington (Australia). School of Chemistry

    1989-12-01

    Benzimidazole carbamates (BZCs) act as inhibitors of the tubulin-microtubule equilibria in eukaryotic organisms. Recently drug resistance to this class of compounds in helminth parasites has been shown to be due to a reduced ability of resistant tubulin to bind BZCs. In order to quantitate the nature of the tubulin-BZC interaction a general method for the specific tritium labelling of BZCs has been developed. The BZCs: mebendazole, oxfendazole, parbendazole, oxibendazole, albendazole and fenbendazole were labelled by catalytic exchange using palladium on calcium carbonate in pure dioxane at 60{sup 0}C under tritium gas. The position of label incorporation for tritiated albendazole was determined by tritium-NMR as the 4-position of benzimadazole nucleus. The yields for individual BZCs varied from 8 to 68% for a range of specific activity of 0.44 to 13.4 Ci/mmole. (author).

  2. Antioxidative and antiproliferative activities of novel pyrido[1,2-a]benzimidazoles.

    Science.gov (United States)

    Tireli, Martina; Starčević, Kristina; Martinović, Tamara; Pavelić, Sandra Kraljević; Karminski-Zamola, Grace; Hranjec, Marijana

    2017-02-01

    A series of pyrido[1,2-a]benzimidazoles has been designed, and novel examples are synthesized and evaluated for their potential antiproliferative activity against four human tumour cell lines-cervical (HeLa), colorectal (SW620), breast (MCF-7) and hepatocellular carcinoma (HepG2). In addition, their antioxidative potency has been evaluated by in vitro spectrophotometric assays. Preliminary structure-activity relationships among the synthesized compounds are discussed. Evaluation of their antioxidative capacity has shown that two compounds (25 and 26) possess promising reducing characteristics and free radical scavenging activity. Selective antiproliferative effect in the single-digit micromolar range was observed for compound 25 on MCF-7 [Formula: see text] and HeLa [Formula: see text] cell lines, comparable to the standards 5-fluorouracil and cisplatin. The combination of the radical scavenging activity and antiproliferative activity of compound 25 positions this compound as a potential lead candidate for further optimization.

  3. Application of QSAR models in analysis of antibacterial activity of some benzimidazole derivatives against Sarcina lutea

    Directory of Open Access Journals (Sweden)

    Podunavac-Kuzmanović Sanja O.

    2013-01-01

    Full Text Available In the present paper, a quantitative structure activity relationship (QSAR has been carried out on a series of 2-methyl and 2-aminobenzimidazole derivatives to identify the lipophilicity requirements for their inhibitory activity against bacteria Sarcina lutea. The tested compounds displayed in vitro antibacterial activity and minimum inhibitory concentration (MIC was determined for all compounds. The partition coefficients of the studied compounds were measured by the shake flask method (log P and by theoretical calculation (Clog P. The relationships between lipophilicity descriptors and antibacterial activities were investigated and the mathematical models have been developed as a calibration models for predicting the inhibitory activity of this class of compounds. The models were validated by leave-one-out (LOO technique as well as by the calculation of statistical parameters for the established models. Therefore, QSAR analysis reveals that lipophilicity descriptor govern the inhibitory activity of benzimidazoles studied against Sarcina lutea.

  4. Antibacterial activity of cobalt(II complexes with some benzimidazole derivatives

    Directory of Open Access Journals (Sweden)

    S. O. PODUNAVAC-KUZMANOVIC

    2008-12-01

    Full Text Available The antibacterial activities of cobalt(II complexes with two series of benzimidazoles were evaluated in vitro against three Gram-positive bacterial strains (Bacillus cereus, Staphylococcus aureus, and Sarcina lutea and one Gram-negative isolate (Pseudomonas aeruginosa. The minimum inhibitory concentration was determined for all the complexes. The majority of the investtigated complexes displayed in vitro inhibitory activity against very persistent bacteria. They were found to be more active against Gram-positive than Gram-negative bacteria. It may be concluded that the antibacterial activity of the compounds is related to the cell wall structure of the tested bacteria. Comparing the inhibitory activities of the tested complexes, it was found that the 1-substituted-2-aminobenzimidazole derivatives were more active than complexes of 1-substituted-2-amino-5,6-dimethylbenzimidazoles. The effect of chemical structure on the antibacterial activity is discussed.

  5. Synthesis and characterization of 2-substituted benzimidazoles and their evaluation as anticancer agent

    Science.gov (United States)

    Azam, Mohammad; Khan, Azmat Ali; Al-Resayes, Saud I.; Islam, Mohammad Shahidul; Saxena, Ajit Kumar; Dwivedi, Sourabh; Musarrat, Javed; Trzesowska-Kruszynska, Agata; Kruszynski, Rafal

    2015-05-01

    In this work, we report a series of benzimidazole derivatives synthesized from benzene-1,2-diamine and aryl-aldehydes at room temperature. The synthesized compounds have been characterized on the basis of elemental analysis and various spectroscopic studies viz., IR, 1H- and 13C-NMR, ESI-MS as well by X-ray single X-ray crystallographic study. Interaction of these compounds with CT-DNA has been examined with fluorescence experiments and showed significant binding ability. All the synthesized compounds have been screened for their antitumor activities against various human cancer cell lines viz., Human breast adenocarcinoma cell line (MCF-7), Human leukemia cell line (THP-1), Human prostate cancer cell lines (PC-3) and adenocarcinomic human alveolar basal epithelial cell lines (A-549). Interestingly, all the compounds showed significant anticancer activity.

  6. Bonding and energy parameters for Pr and Nd complexes of benzimidazoles

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, S; Vyas, P C; Oza, C K [Rajasthan Univ., Jaipur (India). Dept. of Chemistry

    1991-01-01

    Complexes of praseodymium(III) and neodymium(III) with benzimidazoles have been synthesized and characterized by their conductance and infrared spectral studies. The values of interelectronic repulsion, i.e. Slater-Condon (F{sub 2}, F{sub 4}, F{sub 6}), Racah (E{sup 1}, E{sup 2}, E{sup 3}) parameters and spin-orbit interaction referred as Lande' ({zeta}4f) parameters have been calculated from their electronic spectral data. A comparison of these parameters for the complexes with Pr{sup 3+} and Nd{sup 3+} free ion parameters is discussed. Using F{sub 2} values, the nephelauxetic ratio({Beta}) and bonding parameter(b{sup 1/2}) have beeen calculated. The relative variation of covalent bonding in the complexes has been reported. (author). 11 refs., 1 tab.

  7. Activities of several benzimidazoles and tubulin inhibitors against Giardia spp. in vitro.

    Science.gov (United States)

    Morgan, U M; Reynoldson, J A; Thompson, R C

    1993-01-01

    Previous studies in our laboratory have shown that albendazole is effective against Giardia spp. in vitro and in vivo, prompting an investigation of the effects of several related benzimidazoles (BZs) on the viability of this protozoan parasite. A range of BZs was tested, and their effects were compared with those of a number of microtubule inhibitors. The effects produced by the two types of drugs were markedly similar, namely, trophozoite detachment and distortion of morphology and general structure, indicating a potential antimicrotubule mode of action for BZs. Mebendazole, albendazole, and fenbendazole proved to be among the most effective BZs tested, exhibiting apparent irreversibility. Nocodazole, oxfendazole, and albendazole sulfoxide, among others, produced transient inhibitions only. Further studies are required to evaluate all available BZs and other antigiardial agents to ensure the development of the most effective and safest antigiardial agent possible. PMID:8452365

  8. Fluorescence tuning of 2-(1H-Benzimidazol-2-yl)phenol-ESIPT process

    International Nuclear Information System (INIS)

    Prakash, S.M.; Jayamoorthy, K.; Srinivasan, N.; Dhanalekshmi, K.I.

    2016-01-01

    Catalytic synthesis of potential chemosensor 2-(1H-Benzimidazol-2-yl)phenol (HBYP) has been prepared by three components cyclization reaction. It can behaves as a selective fluorescent sensor for the detection of Fe 3+ metal ion. HBYP has been characterized by 1 H NMR, 13 C NMR, mass spectral studies and elemental analysis. Single crystal XRD analysis has been carried out to confirm the structure of HBYP and it shows the imidazole ring is essentially planar and monoclinic crystal. Addition and increasing concentration of Fe 3+ ions into HBYP results dramatic fluorescence quenching. Other cations, including Ca 2+ , Co 2+ , Ni 2+ , Cd 2+ , Pb 2+ , Zn 2+ and Mg 2+ had little influence in the fluorescence intensity. Surprisingly reversible fluorescence enhancement has been observed with the addition of H 3 PO 4 due to the deactivation of iron complex.

  9. Synthesis, analytical analysis, and medicinal aspect of novel benzimidazoles and their metal complexes.

    Science.gov (United States)

    Agrawal, Sangeeta; Bhatnagar, Rishi Raj; Tiwari, Anjani; Srivastava, Rakesh; Sharma, Upasana

    2013-11-01

    Benzimidazole and their metal analogs that can act as multimodal agent and have non-peptidic CCK-B receptor antagonist were synthesized and characterized on the basis of spectroscopic techniques such as FT-IR, NMR, FAB-MS and also evaluated for biologic efficacy. The ligands showed binding to most of the organs, known to express CCK receptors in biodistribution studies. Cholecystokinin (CCK1 and CCK2) receptor binding affinities of these analogs (IC50) are 0.802 ± 0.007 for compound C and 0.326 ± 0.012 for compound D in rat pancreatic acini. These studies have provided a new template for further development of novel agents for various related diseases.

  10. Complexes of Zn(2) and Cd(2) with 2-methyl-benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Slyusarenko, K F; Artemenko, M V; Pokhodnya, G A; Kononenko, O.M. (Kievskij Tekhnologicheskij Inst. Pishchevoj Promyshlennosti (Ukrainian SSR))

    1978-07-01

    Coordination compounds of Zn(2) and Cd(2) salts with 2-methyl-benzimidazole (MBI) of 2MBIxMeX/sub 2/ composition, where Me is Zn (2), Cd (2); X is NO/sub 3//sup -/, CH/sub 3/COO/sup -/, CL/sup -/, Br/sup -/, I/sup -/, 1/2SO/sub 4//sup -2/, as well as acid compounds of (MBIH)/sub 2/(CdX/sub 4/) composition, where X is Cl/sup -/, Br/sup -/, I/sup -/, have been obtained and investigated. The synthetized compounds are of white colour, they are stable in air, soluble in alcohols, decomposed by water. Decomposition temperatures for most of the Cd(2) compounds lie above 250 deg C. Infrared spectra and diffractograms of these compounds have been studied. From the curves of radial distribution of atomic density, the ionic nature of the bonding of halide groups in the complexes has been established.

  11. Solubility improvement of an anthelmintic benzimidazole carbamate by association with dendrimers

    International Nuclear Information System (INIS)

    Fernandez, L.; Sigal, E.; Santo, M.; Otero, L.; Silber, J. J.

    2011-01-01

    The improvement of aqueous solubility of methyl (5-[propylthio]-1H-benzimidazole-2-yl) carbamate, albendazole (ABZ) using polyamidoamine (PAMAM) dendrimers as solubility enhancers was investigated. Full generation PAMAM dendrimers with amine terminal groups, (G3), with hydroxyl terminal groups (G3OH) and half generation PAMAM dendrimers with carboxylate terminal groups (G2.5 and G3.5), were chosen for this study. The nature of dendrimer-ABZ association was investigated by UV absorption, fluorescence emission measurements and by 1 H-NMR spectroscopy. The results obtained show that these polymeric structures have the capacity to enhance the solubility of ABZ, both lipophilic and specific hydrogen bond interactions contributing to the guest-host association. Although all studied dendrimers have hydrophobic internal nanoenvironments with similar dimensions, their surfaces differ significantly and the nature and the localization of the interactions involved in ABZ-dendrimer association depend on the type of terminal groups. (author)

  12. A general method for tritium labelling of benzimidazole carbamates by catalytic exchange in dioxane solutions

    International Nuclear Information System (INIS)

    Lacey, E.; Dawson, M.; Long, M.A.; Than, C.

    1989-01-01

    Benzimidazole carbamates (BZCs) act as inhibitors of the tubulin-microtubule equilibria in eukaryotic organisms. Recently drug resistance to this class of compounds in helminth parasites has been shown to be due to a reduced ability of resistant tubulin to bind BZCs. In order to quantitate the nature of the tubulin-BZC interaction a general method for the specific tritium labelling of BZCs has been developed. The BZCs: mebendazole, oxfendazole, parbendazole, oxibendazole, albendazole and fenbendazole were labelled by catalytic exchange using palladium on calcium carbonate in pure dioxane at 60 0 C under tritium gas. The position of label incorporation for tritiated albendazole was determined by tritium-NMR as the 4-position of benzimadazole nucleus. The yields for individual BZCs varied from 8 to 68% for a range of specific activity of 0.44 to 13.4 Ci/mmole. (author)

  13. Solubility improvement of an anthelmintic benzimidazole carbamate by association with dendrimers

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, L.; Sigal, E.; Santo, M., E-mail: msanto@exa.unrc.edu.ar [Departamento de Fisica, Facultad de Ciencias Exactas Fisicoquimicas y Naturales, Universidad Nacional de Rio Cuarto (Argentina); Otero, L.; Silber, J. J. [Departamento de Quimica. Facultad de Ciencias Exactas Fisicoquimicas y Naturales, Universidad Nacional de Rio Cuarto, Rio Cuarto (Argentina)

    2011-10-15

    The improvement of aqueous solubility of methyl (5-[propylthio]-1H-benzimidazole-2-yl) carbamate, albendazole (ABZ) using polyamidoamine (PAMAM) dendrimers as solubility enhancers was investigated. Full generation PAMAM dendrimers with amine terminal groups, (G3), with hydroxyl terminal groups (G3OH) and half generation PAMAM dendrimers with carboxylate terminal groups (G2.5 and G3.5), were chosen for this study. The nature of dendrimer-ABZ association was investigated by UV absorption, fluorescence emission measurements and by {sup 1}H-NMR spectroscopy. The results obtained show that these polymeric structures have the capacity to enhance the solubility of ABZ, both lipophilic and specific hydrogen bond interactions contributing to the guest-host association. Although all studied dendrimers have hydrophobic internal nanoenvironments with similar dimensions, their surfaces differ significantly and the nature and the localization of the interactions involved in ABZ-dendrimer association depend on the type of terminal groups. (author)

  14. EDITORIAL: Probing the nanoworld Probing the nanoworld

    Science.gov (United States)

    Miles, Mervyn

    2009-10-01

    In nanotechnology, it is the unique properties arising from nanometre-scale structures that lead not only to their technological importance but also to a better understanding of the underlying science. Over the last twenty years, material properties at the nanoscale have been dominated by the properties of carbon in the form of the C60 molecule, single- and multi-wall carbon nanotubes, nanodiamonds, and recently graphene. During this period, research published in the journal Nanotechnology has revealed the amazing mechanical properties of such materials as well as their remarkable electronic properties with the promise of new devices. Furthermore, nanoparticles, nanotubes, nanorods, and nanowires from metals and dielectrics have been characterized for their electronic, mechanical, optical, chemical and catalytic properties. Scanning probe microscopy (SPM) has become the main characterization technique and atomic force microscopy (AFM) the most frequently used SPM. Over the past twenty years, SPM techniques that were previously experimental in nature have become routine. At the same time, investigations using AFM continue to yield impressive results that demonstrate the great potential of this powerful imaging tool, particularly in close to physiological conditions. In this special issue a collaboration of researchers in Europe report the use of AFM to provide high-resolution topographical images of individual carbon nanotubes immobilized on various biological membranes, including a nuclear membrane for the first time (Lamprecht C et al 2009 Nanotechnology 20 434001). Other SPM developments such as high-speed AFM appear to be making a transition from specialist laboratories to the mainstream, and perhaps the same may be said for non-contact AFM. Looking to the future, characterisation techniques involving SPM and spectroscopy, such as tip-enhanced Raman spectroscopy, could emerge as everyday methods. In all these advanced techniques, routinely available probes will

  15. Proximal Probes Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Proximal Probes Facility consists of laboratories for microscopy, spectroscopy, and probing of nanostructured materials and their functional properties. At the...

  16. Probe Techniques. Introductory Remarks

    Energy Technology Data Exchange (ETDEWEB)

    Emeleus, K. G. [School of Physics and Applied Mathematics, Queen' s University, Belfast (United Kingdom)

    1968-04-15

    In this brief introduction to the session on probes, the history of theii development is first touched on briefly. Reference is then made to the significance of the work to be described by Medicus, for conductivity and recombination calculations, and by Lam and Su, for a wide range of medium and higher pressure plasmas. Finally, a number of other probe topics are mentioned, including multiple probes; probes in electronegative plasmas; resonance probes; probes in noisy discharges; probes as oscillation detectors; use of probes where space-charge is not negligible. (author)

  17. SULFONATED POLY(ARYLENE ETHER BENZIMIDAZOLE COPOLYMER MEMBRANE SYNTHESIS AND CHARACTERIZATION

    Directory of Open Access Journals (Sweden)

    Çağla TOSUN

    2015-05-01

    Full Text Available Hidrojenden elektrik enerjisi üretiminde kullanılan yakıt hücreleri, geleceğin çevre dostu ve yüksek verimli enerji üretimine alternatif olarak kabul görmektedirler. Nafion gibi perflorosülfonik asit bazlı membranlar polimer elektrolit membran yakıt hücreleri (PEMHY’nde sıklıkla kullanılmaktadırlar. Ancak Nafion membranların yüksek sıcaklıklarda proton iletkenliklerinin düşmesi ve fiyatlarının yüksek olması nedeniyle alternatif polimer elektrolit membran (PEM’lar üzerine araştırmalar devam etmektedir. Bu çalışmanın ilk aşamasında, disodyum-3,3’-disülfonat-4,4’-diklorodifenilsülfon (SDCDPS ve benzimidazol bisfenol (HPBI monomerlerinin sentezi gerçekleştirilmiştir. Daha sonra sentezlenen monomerlerden nükleofilik aromatik polikondenzasyon reaksiyonu ile poli(arilen eter benzimidazol kopolimeri sentezlenmiştir. Sentezlenen monomerlerin 1H NMR ve FTIR, kopolimerin ise 1H NMR, FTIR ve termogravimetrik analizleri (TGA gerçekleştirilmiştir. Yapılan analizler sonucunda kopolimerin sentezlendiği açıkça ortaya konulmuştur. TGA eğrisi sentezlenen kopolimerin ısıl kararlılığının yüksek olduğunu (~400 oC ve yüksek sıcaklık uygulamalarında kullanılabilirliğini göstermiştir

  18. Comparative plasma disposition kinetics of albendazole and its new benzimidazol prodrug in dog.

    Science.gov (United States)

    Khalil, Z; El Karbane, M; Faouzi, M E A; Ansar, M; Azougagh, M; El Harti, J; Taoufik, J

    2016-01-01

    The comparative pharmacokinetic behavior of albendazole (ABZ) and its new benzimidazol prodrug [1-tert-butyloxycarbonyl-5-propylthio-1-H-benzimidazol-2ylcarbamate of methyl] (ABZBoc), following their oral administration (10mg/kg) to healthy dogs was explored. Blood samples were obtained serially over a 24h period after treatment, then the plasma was analyzed by high-performance liquid chromatography (HPLC) to search the albendazole metabolites (ABZSO and ABZSO2). However, the albendazole parent drug was not detectable at any time after both treatments (ABZ and ABZBoc). By albendazole metabolites (ABZSO and ABZSO2) were the analytes recovered in the plasma after oral administration of ABZ and ABZBoc. Furthermore, some amounts of ABZBoc were also available in the plasma samples treated with this new produg. The plasma profile of each analyte followed a similar pattern after both treatments, the active metabolite (ABZSO) was the major analyte recovered in plasma (between 1 and 24h post-treatment). The pharmacokinetic parameters of both groups were calculated (Cmax, Tmax, t1/2, AUC0-›∞), and analyzed using the Student's t-test, Palbendazole metabolites (ABZSO, ABZSO2) between the group treated with albendazole (group A) and that treated with ABZBoc prodrug (group B). Hence, the levels of the various pharmacokinetics parameters were low in the group treated with prodrug, as well they did not reach equivalent concentrations to that of albendazole. These differences between albendazole and its new prodrug may be explained by the fact that ABZBoc prodrug was not effectively reduced in the intestine of dogs. Copyright © 2015 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.

  19. One-by-one single-molecule detection of mutated nucleobases by monitoring tunneling current using a DNA tip.

    Science.gov (United States)

    Bui, Phuc Tan; Nishino, Tomoaki; Shiigi, Hiroshi; Nagaoka, Tsutomu

    2015-01-31

    A DNA molecule was utilized as a probe tip to achieve single-molecule genetic diagnoses. Hybridization of the probe and target DNAs resulted in electron tunneling along the emergent double-stranded DNA. Simple stationary monitoring of the tunneling current leads to single-molecule DNA detection and discovery of base mismatches and methylation.

  20. 1-Benzyl-2-Phenylbenzimidazole (BPB, a Benzimidazole Derivative, Induces Cell Apoptosis in Human Chondrosarcoma through Intrinsic and Extrinsic Pathways

    Directory of Open Access Journals (Sweden)

    Ju-Fang Liu

    2012-12-01

    Full Text Available In this study, we investigated the anticancer effects of a new benzimidazole derivative, 1-benzyl-2-phenyl -benzimidazole (BPB, in human chondrosarcoma cells. BPB-mediated apoptosis was assessed by the MTT assay and flow cytometry analysis. The in vivo efficacy was examined in a JJ012 xenograft model. Here we found that BPB induced apoptosis in human chondrosarcoma cell lines (JJ012 and SW1353 but not in primary chondrocytes. BPB induced upregulation of Bax, Bad and Bak, downregulation of Bcl-2, Bid and Bcl-XL and dysfunction of mitochondria in chondrosarcoma. In addition, BPB also promoted cytosolic releases AIF and Endo G. Furthermore, it triggered extrinsic death receptor-dependent pathway, which was characterized by activating Fas, FADD and caspase-8. Most importantly, animal studies revealed a dramatic 40% reduction in tumor volume after 21 days of treatment. Thus, BPB may be a novel anticancer agent for the treatment of chondrosarcoma.

  1. Synthesis and Biological Evaluation of Novel Benzimidazole Derivatives Bearing a Heterocyclic Ring at 4/5 Position

    International Nuclear Information System (INIS)

    Wubulikasimu, Reyila; Yang, Yanbing; Xue, Fei; Luo, Xianjin; Shao, Dongping; Li, Yuhuan; Gao, Rongmei; Ye, Weidong

    2013-01-01

    A series of novel benzimidazole derivatives bearing a heterocyclic ring as oxadiazole (21-32), thiadiazole (33-34), triazole (35-36) were synthesized and evaluated for their activities against Coxsackie virus B3 and B6 in Vero cells. Compounds 21-26, 31-36 with moieties of 2'-pyridyl, 3'-pyridyl and 4'-pyridyl at the 2-position and oxadiazoles, thiadiazole, or triazole substituent at the 4- or 5-position generally displayed activities against CVB3 and CVB6. Especially compound 24 (IC 50 = 1.08 μg/mL, SI = 61.7 against CVB3) was the promising candidate as lead compound for anti-enteroviral drug. It was observed in the incorporation of heterocyclic rings in benzimidazole at the 5-position could enhance their biological activities

  2. Synthesis and properties of poly(aryl sulfone benzimidazole) and its copolymers for high temperature membrane electrolytes for fuel cells

    DEFF Research Database (Denmark)

    Yang, Jingshuai; Li, Qingfeng; Cleemann, Lars Nilausen

    2012-01-01

    Poly(aryl sulfone benzimidazole) (SO2PBI) and its copolymers with poly[2,2′-p-(phenylene)-5,5′-bibenzimidazole] (pPBI), termed as Co-SO2PBI, were synthesized with varied feeding ratios of 4,4′-sulfonyldibenzoic acid (SDBA) to terephthalic acid (TPA). Incorporation of the stiff para-phenylene and ......Poly(aryl sulfone benzimidazole) (SO2PBI) and its copolymers with poly[2,2′-p-(phenylene)-5,5′-bibenzimidazole] (pPBI), termed as Co-SO2PBI, were synthesized with varied feeding ratios of 4,4′-sulfonyldibenzoic acid (SDBA) to terephthalic acid (TPA). Incorporation of the stiff para...

  3. Design, synthesis and biological evaluation of 5-fluorouracil-derived benzimidazoles as novel type of potential antimicrobial agents.

    Science.gov (United States)

    Fang, Xue-Jie; Jeyakkumar, Ponmani; Avula, Srinivasa Rao; Zhou, Qian; Zhou, Cheng-He

    2016-06-01

    A series of 5-fluorouracil benzimidazoles as novel type of potential antimicrobial agents were designed and synthesized for the first time. Bioactive assay manifested that some of the prepared compounds exhibited good or even stronger antibacterial and antifungal activities against the tested strains in comparison with reference drugs norfloxacin, chloromycin and fluconazole. Noticeably, 3-fluorobenzyl benzimidazole derivative 5c gave remarkable antimicrobial activities against Saccharomyces cerevisiae, MRSA and Bacillus proteus with MIC values of 1, 2 and 4μg/mL, respectively. Experimental research revealed that compound 5c could effectively intercalate into calf thymus DNA to form compound 5c-DNA complex which might block DNA replication and thus exert antimicrobial activities. Molecular docking indicated that compound 5c should bind with DNA topoisomerase IA through three hydrogen bonds by the use of fluorine atom and oxygen atoms in 5-fluorouracil with the residue Lys 423. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Structural Modifications of Benzimidazoles via Multi-Step Synthesis and Their Impact on Sirtuin-Inhibitory Activity.

    Science.gov (United States)

    Yoon, Yeong Keng; Choon, Tan Soo

    2016-01-01

    Benzimidazole derivatives have been shown to possess sirtuin-inhibitory activity. In the continuous search for potent sirtuin inhibitors, systematic changes on the terminal benzene ring were performed on previously identified benzimidazole-based sirtuin inhibitors, to further investigate their structure-activity relationships. It was demonstrated that the sirtuin activities of these novel compounds followed the trend where meta-substituted compounds possessed markedly weaker potency than ortho- and para-substituted compounds, with the exception of halogenated substituents. Molecular docking studies were carried out to rationalize these observations. Apart from this, the methods used to synthesize the interesting compounds are also discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Impact of zeolite-Y framework on the geometry and reactivity of Ru (III) benzimidazole complexes - A DFT study

    Science.gov (United States)

    Selvaraj, Tamilmani; Rajalingam, Renganathan; Balasubramanian, Viswanathan

    2018-03-01

    A detailed comparative Density Functional Theory (DFT) study is made to understand the structural changes of the guest complex due to steric and electronic interactions with the host framework. In this study, Ru(III) benzimidazole and 2- ethyl Ru(III) benzimidazole complexes encapsulated in a supercage of zeolite Y. The zeolitic framework integrity is not disturbed by the intrusion of the large guest complex. A blue shift in the d-d transition observed in the UV-Visible spectroscopic studies of the zeolite encapsulated complexes and they shows a higher catalytic efficiency. Encapsulation of zeolite matrix makes the metal center more viable to nucleophilic attack and favors the phenol oxidation reaction. Based on the theoretical calculations, transition states and structures of reaction intermediates involved in the catalytic cycles are derived.

  6. Gold nanoparticles supported on titanium dioxide: an efficient catalyst for highly selective synthesis of benzoxazoles and benzimidazoles.

    Science.gov (United States)

    Tang, Lin; Guo, Xuefeng; Yang, Yu; Zha, Zhenggen; Wang, Zhiyong

    2014-06-11

    A highly efficient and selective reaction for the synthesis of 2-substituted benzoxazoles and benzimidazoles catalyzed by Au/TiO2 has been developed via two hydrogen-transfer processes. This reaction has a good tolerance to air and water, a wide substrate scope, and represents a new avenue for practical C-N and C-O bond formation. More importantly, no additional additives, oxidants and reductants are required for the reaction and the catalyst can be recovered and reused readily.

  7. NaHSO4-SiO2-Promoted Solvent-Free Synthesis of Benzoxazoles, Benzimidazoles, and Benzothiazole Derivatives

    Directory of Open Access Journals (Sweden)

    K. Ravi Kumar

    2013-01-01

    Full Text Available An efficient protocol has been developed for the preparation of a library of benzoxazole, benzimidazole, and benzothiazole derivatives from reactions of acyl chlorides with o-substituted aminoaromatics in the presence of catalytic amount of silica-supported sodium hydrogen sulphate under solvent-free conditions. Simple workup procedure, high yield, easy availability, reusability, and use of ecofriendly catalyst are some of the striking features of the present protocol.

  8. Synthesis of 4-(3-t-butylamino-2-hydroxypropoxy)- benzimidazol -2 (/sup 11/C)-one (CGP 12177)

    Energy Technology Data Exchange (ETDEWEB)

    Boullais, C; Crouzel, C; Syrota, A

    1986-05-01

    4-(3-t-butylamino-2-hydroxypropoxy)-benzimidazol-2 (/sup 11/C)-one (CGP 12177) was synthesized in a short time (30 min) and with a specific activity of 130 mCi/..mu..Mo1 for ..beta.. receptor studies by the positron emission tomography. The radioactive reagent was /sup 11/C-phosgene and the starting material 1-(3-t-butylamino-2-hydroxypropoxy)-2,3-diamino benzene.

  9. Design and synthesis of N₁-aryl-benzimidazoles 2-substituted as novel HIV-1 non-nucleoside reverse transcriptase inhibitors.

    Science.gov (United States)

    Monforte, Anna-Maria; Ferro, Stefania; De Luca, Laura; Lo Surdo, Giuseppa; Morreale, Francesca; Pannecouque, Christophe; Balzarini, Jan; Chimirri, Alba

    2014-02-15

    A series of novel N1-aryl-2-arylthioacetamido-benzimidazoles were synthesized and evaluated as inhibitors of human immunodeficiency virus type-1 (HIV-1). Some of them proved to be effective in inhibiting HIV-1 replication at submicromolar and nanomolar concentration acting as HIV-1 non-nucleoside RT inhibitors (NNRTIs), with low cytotoxicity. The preliminary structure-activity relationship (SAR) of these new derivatives was discussed and rationalized by docking studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Polystyrene-supported pyridinium chloroaluminate ionic liquid as a new heterogeneous Lewis acid catalyst for selective synthesis of benzimidazoles

    Directory of Open Access Journals (Sweden)

    Parvanak Boroujeni Kaveh

    2013-01-01

    Full Text Available Polystyrene-supported pyridinium chloroaluminate ionic liquid was prepared from the reaction of Merrifield resin with pyridine followed by reaction with aluminium chloride. This catalyst was used as a new chemoselective Lewis acid catalyst for the exclusive synthesis of 2-substituted benzimidazoles from the reaction of aldehydes with o-phenylenediamines. The catalyst is stable (as a bench top catalyst and can be easily recovered and reused without appreciable change in its efficiency.

  11. Genetically encoded fluorescent probe to visualize phosphatidylinositol

    Czech Academy of Sciences Publication Activity Database

    Eisenreichová, Andrea; Humpolíčková, Jana; Bouřa, Evžen

    2017-01-01

    Roč. 284, Suppl 1 (2017), s. 364-365 ISSN 1742-464X. [FEBS Congress /42./ From Molecules to Cells and Back. 10.09.2017-14.09.2017, Jerusalem] R&D Projects: GA ČR GJ15-21030Y; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : phosphatidylinositol * fluorescent probe Subject RIV: CE - Biochemistry

  12. Alternative energy production pathways in Taenia crassiceps cysticerci in vitro exposed to a benzimidazole derivative (RCB20).

    Science.gov (United States)

    Fraga, Carolina Miguel; Da Costa, Tatiane Luiza; De Castro, Ana Maria; Reynoso-Ducoing, Olivia; Ambrosio, Javier; Hernández-Campos, Alicia; Castillo, Rafael; Vinaud, Marina Clare

    2016-04-01

    Biochemical studies of benzimidazole derivatives are important to determine their mode of action and activity against parasites. The lack of antihelminthic alternatives to treat parasitic infections and albendazole resistance cases make the search for new antiparasitary drugs of utmost importance. The 6-chloro-5-(1-naphthyloxy)-2-(trifluoromethyl)-1H-benzimidazole (RCB20) is a benzimidazole derivative with promising effect. This study evaluated the effect of different concentrations of RCB20 in the alternative energetic pathway of in vitro Taenia crassiceps cysticerci. The parasites were in vitro exposed to 6.5 and 13 µM of RCB20 and albendazole sulfoxide (ABZSO). The quantification of acetate, acetoacetate, β-hydroxybutyrate, fumarate and propionate was performed by high-performance liquid chromatography. The quantification of urea, creatinine and total proteins was performed by spectrophotometry. The increase in β-hydroxybutyrate reflects the enhancement of the fatty acid oxidation in the treated groups. Volatile fatty acids secretion, acetate and propionate, was increased in the treated groups. The secretion mechanisms of the treated parasites were impaired due to organic acids increased concentrations in the cysticerci. It is possible to conclude that the metabolic effect on alternative energetic pathways is slightly increased in the parasites treated with RCB20 than the ones treated with ABZSO.

  13. Synthesis of substituted 2-(β-D-glucopyranosyl)-benzimidazoles and their evaluation as inhibitors of glycogen phosphorylase.

    Science.gov (United States)

    Bokor, Éva; Szilágyi, Enikő; Docsa, Tibor; Gergely, Pál; Somsák, László

    2013-11-15

    Microwave assisted condensation of O-perbenzoylated C-(β-d-glucopyranosyl)formic acid with 1,2-diaminobenzenes in the presence of triphenylphosphite gave the corresponding O-protected 2-(β-d-glucopyranosyl)-benzimidazoles in moderate yields. O-Perbenzoylated C-(β-d-glucopyranosyl)formamide and -thioformamide were transformed into the corresponding ethyl C-(β-d-glucopyranosyl)formimidate and -thioformimidate, respectively, by Et3O·BF4. Treatment of the formimidate with 1,2-diaminobenzenes afforded O-protected 2-(β-d-glucopyranosyl)-benzimidazoles in good to excellent yields. Similar reaction of the thioformimidate gave these compounds in lower yields. The O-benzoyl protecting groups were removed by the Zemplén protocol. These test compounds were assayed against rabbit muscle glycogen phosphorylase (GP) b, the prototype of liver GP, the rate limiting enzyme of glycogen degradation. The best inhibitors were 2-(β-d-glucopyranosyl)-4-methyl-benzimidazole (Ki=2.8μM) and 2-(β-d-glucopyranosyl)-naphtho[2,3-d]imidazole (Ki=2.1μM) exhibiting a ∼3-4 times stronger binding than the unsubstituted parent compound. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Improvement of surface wettability and interfacial adhesion of poly-(p-phenylene terephthalamide) by incorporation of the polyamide benzimidazole segment

    International Nuclear Information System (INIS)

    Cai Renqin; Peng Tao; Wang Fengde; Ye Guangdou; Xu Jianjun

    2011-01-01

    In order to investigate the effect of the polyamide benzimidazole group on the surface wettability and interfacial adhesion of fiber/matrix composites, surface features of two kinds of aramid fibers, poly (p-phenylene terephthalamide) fiber (Kevlar-49) and poly-(polyamide benzimidazole-co-p-phenylene terephthalamide) (DAFIII), have been analyzed by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and contact angle analysis (CAA) system, respectively. The results show that with the incorporation of the polyamide benzimidazole segment, more polar functional groups exist on DAFIII surface. The contact angles of water and diiodomethane on DAFIII surface get smaller. The surface free energy of DAFIII increases to 36.5 mJ/m 2 , which is 2.3% higher than that of Kevlar-49. In addition, DAFIII has a larger rough surface compared with that of Kevlar-49 due to different spinning processes. The interfacial shear strength (IFSS) of DAFIII/matrix composite is 25.7% higher than that of Kevlar-49/matrix composite, in agreement with the observed results from surface feature tests. SEM micrographs of failed micro-droplet specimens reveal a strong correlation between the fracture features and the observed test data.

  15. N-H···S Interaction Continues To Be an Enigma: Experimental and Computational Investigations of Hydrogen-Bonded Complexes of Benzimidazole with Thioethers.

    Science.gov (United States)

    Wategaonkar, Sanjay; Bhattacherjee, Aditi

    2018-05-03

    The N-H···S hydrogen bond, even though classified as an unconventional hydrogen bond, is found to bear important structural implications on protein structure and folding. In this article, we report a gas-phase study of the N-H···S hydrogen bond between the model compounds of histidine (benzimidazole, denoted BIM) and methionine (dimethyl sulfide, diethyl sulfide, and tetrahydrothiophene, denoted Me 2 S, Et 2 S, and THT, respectively). A combination of laser spectroscopic methods such as laser-induced fluorescence (LIF), two-color resonant two-photon ionization (2cR2PI), and fluorescence depletion by infrared spectroscopy (FDIR) is used in conjunction with DFT and ab initio calculations to characterize the nature of this prevalent H-bonding interaction in simple bimolecular complexes. A single conformer was found to exist for the BIM-Me 2 S complex, whereas the BIM-Et 2 S and BIM-THT complexes showed the presence of three and two conformers, respectively. These conformers were characterized on the basis of IR spectroscopic results and electronic structure calculations. Quantum theory of atoms in molecules (QTAIM), natural bond orbital (NBO), and energy decomposition (NEDA) analyses were performed to investigate the nature of the N-H···S H-bond. Comparison of the results with the N-H···O type of interactions in BIM and indole revealed that the strength of the N-H···S H-bond is similar to N-H···O in these binary gas-phase complexes.

  16. Inhibiting properties of benzimidazole films for Cu(II)/Cu(I) reduction in chloride media studied by RDE and EQCN techniques

    Energy Technology Data Exchange (ETDEWEB)

    Scendo, M. [Institute of Chemistry, Saint Cross Academy, ul. Checinska 5, 25020 Kielce (Poland)]. E-mail: scendo@pu.kielce.pl; Hepel, M. [Department of Chemistry, State University of New York, Potsdam, NY 13676, USA (United States)

    2007-08-15

    The effects of benzimidazole (BIM) and 2-methylbenzimidazole (MBIM) on the electroreduction of Cu(II) on a rotating Pt disk electrode in chloride media were investigated. These studies were undertaken in conjunction with earlier observation that these imidazole derivatives act as inhibitors of copper corrosion processes and are non-toxic. We have found that BIM and MBIM also form adsorption films on Pt, which are able to inhibit one-electron reduction of Cu(II) to Cu(I) and prevent the development of convective diffusion limiting current wave. The inhibition was found to be controlled by field-assisted mass transfer in the film. The ingress of Cu(II) species into the film was detected using the EQCN technique. The EQCN measurements indicate that small fraction of Cu(I) formed in the film by reduction of Cu(II) is retained in the film, most likely in the form of CuCl. The uptake of CuCl by inhibitor films diminishes in strongly inhibiting films (e.g., in acidic medium). The inhibition effectiveness of Cu(II) reduction process by Pt vertical bar BIM and Pt vertical bar MBIM films increases strongly with increasing acidity of the medium in the pH range from 3.0 to 1.0. The mechanism of this remarkable pH effect has been proposed. It is based on charge and pH-induced film restructuring, including changes in orientation and protonation of BIM molecules in the film.

  17. Slow, spontaneous degradation of lansoprazole, omeprazole and pantoprazole tablets: isolation and structural characterization of the toxic antioxidants 3H-benzimidazole-2-thiones.

    Science.gov (United States)

    Rajab, A; Touma, M; Rudler, H; Afonso, C; Seuleiman, M

    2013-09-01

    The spontaneous degradation of lansoprazole, omeprazole and pantoprazole tablets upon long-term and forced storage conditions was determined by high performance liquid chromatography (HPLC). The more abundant products could be isolated by liquid chromatography and their molecular weights determined by Mass Spectrometry (MS). Their structures, established according to their spectroscopic data, were compared to those of either the literature or of authentic samples. Thus lansoprazole led mainly to a mixture of 3H-benzimidazole-2-thione (2a) and 3H-benzimidazole-2-one (2c), omeprazole mainly to a mixture of 5-methoxy-3H-benzimidazole-2-thione (1a) and 2-hydroxymethyl-3, 5-dimethyl-4-methoxypyridine (1b), and pantoprazole, to 5-difluoromethoxy-3H-benzimidazole-2-thione (3a) and 2-hydroxymethyl-3, 4-dimethoxypyridine (3b). Although some of the degradation products had already been observed under different conditions, the detection of benzimidazole-2-thiones is unprecedented and their involvement as possible physiological, yet toxic antioxidants must be emphasized. Plausible, unified mechanisms for the formation of the different degradation products observed herein and in previous papers from the literature are suggested.

  18. Activity of benzimidazoles against Dientamoeba fragilis (Trichomonadida, Monocercomonadidae in vitro and correlation of beta-tubulin sequences as an indicator of resistance

    Directory of Open Access Journals (Sweden)

    Stark Damien

    2014-01-01

    Full Text Available Recently, Dientamoeba fragilis has emerged as a significant and common enteropathogen. The majority of patients with dientamoebiasis present with gastrointestinal complaints and chronic symptoms are common. Numerous studies have successfully demonstrated parasite clearance, coupled with complete resolution of clinical symptoms following treatment with various antiparasitic compounds. Despite this, there is very little in vitro susceptibility data available for the organism. Benzimidazoles are a class of antiparasitic drugs that are commonly used for the treatment of protozoan and helminthic infections. Susceptibility testing was undertaken on four D. fragilis clinical isolates against the following benzimidazoles: albendazole, flubendazole, mebendazole, nocodazole, triclabendazole and thiabendazole. The activities of the antiprotozoal compounds at concentrations ranging from 2 μg/mL to 500 μg/mL were determined via cell counts of D. fragilis grown in xenic culture. All tested drugs showed no efficacy. The beta-tubulin transcript was sequenced from two of the D. fragilis isolates and amino acid sequences predicted a susceptibility to benzimidazoles. This is the first study to report susceptibility profiles for benzimidazoles against D. fragilis, all of which were not active against the organism. This study also found that beta-tubulin sequences cannot be used as a reliable marker for resistance of benzimidazoles in D. fragilis.

  19. Activity of benzimidazoles against Dientamoeba fragilis (Trichomonadida, Monocercomonadidae) in vitro and correlation of beta-tubulin sequences as an indicator of resistance.

    Science.gov (United States)

    Stark, Damien; Barratt, Joel L N; Roberts, Tamalee; Marriott, Deborah; Harkness, John T; Ellis, John

    2014-01-01

    Recently, Dientamoeba fragilis has emerged as a significant and common enteropathogen. The majority of patients with dientamoebiasis present with gastrointestinal complaints and chronic symptoms are common. Numerous studies have successfully demonstrated parasite clearance, coupled with complete resolution of clinical symptoms following treatment with various antiparasitic compounds. Despite this, there is very little in vitro susceptibility data available for the organism. Benzimidazoles are a class of antiparasitic drugs that are commonly used for the treatment of protozoan and helminthic infections. Susceptibility testing was undertaken on four D. fragilis clinical isolates against the following benzimidazoles: albendazole, flubendazole, mebendazole, nocodazole, triclabendazole and thiabendazole. The activities of the antiprotozoal compounds at concentrations ranging from 2 μg/mL to 500 μg/mL were determined via cell counts of D. fragilis grown in xenic culture. All tested drugs showed no efficacy. The beta-tubulin transcript was sequenced from two of the D. fragilis isolates and amino acid sequences predicted a susceptibility to benzimidazoles. This is the first study to report susceptibility profiles for benzimidazoles against D. fragilis, all of which were not active against the organism. This study also found that beta-tubulin sequences cannot be used as a reliable marker for resistance of benzimidazoles in D. fragilis. D. Stark et al., published by EDP Sciences, 2014

  20. Probing the molecules of the mind | Mendelow | African Journal of ...

    African Journals Online (AJOL)

    The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like more information about how to print, save, and work with PDFs, Highwire Press provides a helpful Frequently Asked Questions about PDFs.

  1. Small Molecules from Spiders Used as Chemical Probes

    DEFF Research Database (Denmark)

    Olsen, Christian Adam; Kristensen, Anders S.; Strømgaard, Kristian

    2011-01-01

    Spiders are important species in ecological systems and as major predators of insects they are endowed with a plethora of low‐molecular‐weight natural products having intriguing biological activities. The isolation and biological characterization of these entities are well established, however......, only very recently have these compounds been used as templates for the design, synthesis, and biological evaluation of synthetic analogues. In contrast, the investigation of compounds responsible for chemical communication between spiders is far less developed, but recently new light has been shed onto...... the area of pheromones and allomones from spiders. Herein, we recapitulate these recent results, put them into perspective with previous findings, and provide an outlook for future studies of these chemotypes....

  2. Probing the molecules of the mind | Mendelow | African Journal of ...

    African Journals Online (AJOL)

    This review outlines basic principles of molecular medicine from the perspective of the human genome project and its role in enabling rapid progress in the understanding of molecular neuro-anatomy, physiology and pathology. These insights have facilitated rather than complicated the diagnostic process, and have paved ...

  3. Biological mechanisms, one molecule at a time

    Science.gov (United States)

    Tinoco, Ignacio; Gonzalez, Ruben L.

    2011-01-01

    The last 15 years have witnessed the development of tools that allow the observation and manipulation of single molecules. The rapidly expanding application of these technologies for investigating biological systems of ever-increasing complexity is revolutionizing our ability to probe the mechanisms of biological reactions. Here, we compare the mechanistic information available from single-molecule experiments with the information typically obtained from ensemble studies and show how these two experimental approaches interface with each other. We next present a basic overview of the toolkit for observing and manipulating biology one molecule at a time. We close by presenting a case study demonstrating the impact that single-molecule approaches have had on our understanding of one of life's most fundamental biochemical reactions: the translation of a messenger RNA into its encoded protein by the ribosome. PMID:21685361

  4. Mobile Game Probes

    DEFF Research Database (Denmark)

    Borup Lynggaard, Aviaja

    2006-01-01

    This paper will examine how probes can be useful for game designers in the preliminary phases of a design process. The work is based upon a case study concerning pervasive mobile phone games where Mobile Game Probes have emerged from the project. The new probes are aimed towards a specific target...... group and the goal is to specify the probes so they will cover the most relevant areas for our project. The Mobile Game Probes generated many interesting results and new issues occurred, since the probes came to be dynamic and favorable for the process in new ways....

  5. Raman Optical Activity of Biological Molecules

    Science.gov (United States)

    Blanch, Ewan W.; Barron, Laurence D.

    Now an incisive probe of biomolecular structure, Raman optical activity (ROA) measures a small difference in Raman scattering from chiral molecules in right- and left-circularly polarized light. As ROA spectra measure vibrational optical activity, they contain highly informative band structures sensitive to the secondary and tertiary structures of proteins, nucleic acids, viruses and carbohydrates as well as the absolute configurations of small molecules. In this review we present a survey of recent studies on biomolecular structure and dynamics using ROA and also a discussion of future applications of this powerful new technique in biomedical research.

  6. Hadronic molecules with hidden charm and bottom

    Directory of Open Access Journals (Sweden)

    Guo Feng-Kun

    2016-01-01

    Full Text Available Many of the new structures observed since 2003 in experiments in the heavy quarkonium mass region, such as the X(3872 and Zc (3900, are rather close to certain thresholds, and thus can be good candidates of hadronic molecules, which are loose bound systems of hadrons. We will discuss the consequences of heavy quark symmetry for hadronic molecules with heavy quarks. We will also emphasize that the hadronic molecular component of a given structure can be directly probed in long-distance processes, while the short-distance processes are not sensitive to it.

  7. Single Molecule Spectroscopy of Electron Transfer

    International Nuclear Information System (INIS)

    Holman, Michael; Zang, Ling; Liu, Ruchuan; Adams, David M.

    2009-01-01

    The objectives of this research are threefold: (1) to develop methods for the study electron transfer processes at the single molecule level, (2) to develop a series of modifiable and structurally well defined molecular and nanoparticle systems suitable for detailed single molecule/particle and bulk spectroscopic investigation, (3) to relate experiment to theory in order to elucidate the dependence of electron transfer processes on molecular and electronic structure, coupling and reorganization energies. We have begun the systematic development of single molecule spectroscopy (SMS) of electron transfer and summaries of recent studies are shown. There is a tremendous need for experiments designed to probe the discrete electronic and molecular dynamic fluctuations of single molecules near electrodes and at nanoparticle surfaces. Single molecule spectroscopy (SMS) has emerged as a powerful method to measure properties of individual molecules which would normally be obscured in ensemble-averaged measurement. Fluctuations in the fluorescence time trajectories contain detailed molecular level statistical and dynamical information of the system. The full distribution of a molecular property is revealed in the stochastic fluctuations, giving information about the range of possible behaviors that lead to the ensemble average. In the case of electron transfer, this level of understanding is particularly important to the field of molecular and nanoscale electronics: from a device-design standpoint, understanding and controlling this picture of the overall range of possible behaviors will likely prove to be as important as designing ia the ideal behavior of any given molecule.

  8. Synthesis of benzimidazole-grafted graphene oxide/multi-walled carbon nanotubes composite for supercapacitance application

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Rajesh Kr., E-mail: r05bhu@gmail.com [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore (Singapore); Xingjue, Wang [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore (Singapore); Kumar, Vinod [Department of Zoology, Banaras Hindu University, Varanasi (India); Srivastava, Anchal [Department of Physics, Banaras Hindu University, Varanasi (India); Singh, Vidya Nand [CSIR-National Physical Laboratory, New Delhi (India)

    2014-11-05

    Highlights: • We are reporting supercapacitance performance of BI-GO/MWCNTs composite. • The specific capacitance of BI-GO/MWCNTs is 275 and 460 F/g at 200 and 5 mV/s scan rate. • This composite has shown 224 F/g capacitance after 1300 cycles at 200 mV/s scan rate. - Abstract: We are reporting the fabrication, characterizations and supercapacitance performance of benzimidazole-grafted graphene oxide/multi-walled carbon nanotubes (BI-GO/MWCNTs) composite. The synthesis of BI-GO materials involves cyclization reaction of carboxylic groups on GO among the hydroxyl and amino groups on o-phenylenediamine. The BI-GO/MWCNTs composite has been fabricated via in situ reduction of BI-GO using hydrazine in presence of MWCNTs. Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Raman spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) have been used to characterize its surface and elemental composition. The uniform dispersion of MWCNTs with BI-GO helps to improve the charge transfer reaction during electrochemical process. The specific capacitance of BI-GO/MWCNTs composite is 275 and 460 F/g at 200 and 5 mV/s scan rate in 1 mol/L aqueous solution of H{sub 2}SO{sub 4}. This BI-GO/MWCNTs composite has shown 224 F/g capacitance after 1300 cycles at 200 mV/s scan rate, which represents its good electrochemical stability.

  9. Synthesis of benzimidazole-grafted graphene oxide/multi-walled carbon nanotubes composite for supercapacitance application

    International Nuclear Information System (INIS)

    Srivastava, Rajesh Kr.; Xingjue, Wang; Kumar, Vinod; Srivastava, Anchal; Singh, Vidya Nand

    2014-01-01

    Highlights: • We are reporting supercapacitance performance of BI-GO/MWCNTs composite. • The specific capacitance of BI-GO/MWCNTs is 275 and 460 F/g at 200 and 5 mV/s scan rate. • This composite has shown 224 F/g capacitance after 1300 cycles at 200 mV/s scan rate. - Abstract: We are reporting the fabrication, characterizations and supercapacitance performance of benzimidazole-grafted graphene oxide/multi-walled carbon nanotubes (BI-GO/MWCNTs) composite. The synthesis of BI-GO materials involves cyclization reaction of carboxylic groups on GO among the hydroxyl and amino groups on o-phenylenediamine. The BI-GO/MWCNTs composite has been fabricated via in situ reduction of BI-GO using hydrazine in presence of MWCNTs. Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Raman spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) have been used to characterize its surface and elemental composition. The uniform dispersion of MWCNTs with BI-GO helps to improve the charge transfer reaction during electrochemical process. The specific capacitance of BI-GO/MWCNTs composite is 275 and 460 F/g at 200 and 5 mV/s scan rate in 1 mol/L aqueous solution of H 2 SO 4 . This BI-GO/MWCNTs composite has shown 224 F/g capacitance after 1300 cycles at 200 mV/s scan rate, which represents its good electrochemical stability

  10. Estimation of the cost of large-scale school deworming programmes with benzimidazoles.

    Science.gov (United States)

    Montresor, A; Gabrielli, A F; Diarra, A; Engels, D

    2010-02-01

    This study estimates the cost of distributing benzimidazole tablets in the context of school deworming programmes: we analysed studies reporting the cost of school deworming from seven countries in four WHO regions. The estimated cost for drug procurement to cover one million children (including customs clearance and international transport) is approximately US$20000. The estimated financial costs (including the cost of training of personnel, drug transport, social mobilization and monitoring) is, on average, equivalent to US$33000 per million school-age children with minimal variation in different countries and continents. The estimated economic costs of distribution (including the time spent by teachers, and health personnel at central, provincial and district level) to cover one million children approximately corresponds to US$19000. This study shows the minimal cost of school deworming activities, but also shows the significant contribution (corresponding to a quarter of the entire cost of the programme) provided by health and education systems in endemic countries even in the case of drug donations and donor support of distribution costs. Copyright 2009 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  11. Methodology for determination of benzimidazolic fungicides residues in strawberry and lettuce by HPLC-DAD

    International Nuclear Information System (INIS)

    Dangond Araujo, Jose Jairo; Guerrero dallos, Jairo Arturo

    2006-01-01

    systemic fungicides like benzimidazolic compounds are used to protect several crops of fruits and vegetables. in this work a new method for analysis of Benomyl, carbendazim and thiabendazol in strawberry and lettuce by high performance liquid chromatography with diode array detector (HPLC-DAD) was validated. benomyl residues were determined after its conversion to carbendazim. pesticide residues were extracted from strawberry and lettuce samples with ethyl acetate and these extracts were cleaned up by gel permeation chromatography (GPC). final determination was carried out by HPLC-DAD in reverse phase column. the method is selective, specific, precise and accurate. the calibration curves show linearity over concentration range of 1.24 to 6.19 mg/kg, with detection limits of 0.40 and 0.27 mg/kg and quantification limits of 1.35 and 0.81 mg/kg for carbendazim and thiabendazole respectively. the recovery experiments yielding averages of 90 %. n o residues of these compounds were found in collected samples from specific areas of Cundinamarca, Colombia

  12. Preparation and proton conductivity of composite membranes based on sulfonated poly(phenylene oxide) and benzimidazole

    International Nuclear Information System (INIS)

    Liu Yifeng; Yu Qinchun; Wu Yihua

    2007-01-01

    The Bronsted acid-base composite membrane was prepared by entrapping benzimidazole in sulfonated poly(phenylene oxide) by tuning the doping ratios. Their thermal stability, dynamic mechanical properties and proton conductivity were investigated under the conditions for intermediate temperature proton exchange membrane (PEM) fuel cell operation. In addition, investigation of activation energies of the SPPO-xBnIm at different relative humidity was also performed. TG-DTA curves reveal these SPPO-xBnIm composite materials had the high thermal stability. The proton conductivity of SPPO-xBnIm composite material increased with the temperature, and the highest proton conductivity of SPPO-xBnIm composite materials was found to be 8.93 x 10 -4 S/cm at 200 deg. C under 35% relative humidity (RH) with a 'doping rate' where x = 2. The SPPO-2BnIm composite membrane show higher storage moduli and loss moduli than SPPO. Tests in a hydrogen-air laboratory cell demonstrate the applicability of SPPO-2BnIm in PEMFCs at intermediate temperature under non-humidified conditions

  13. wALADin benzimidazoles differentially modulate the function of porphobilinogen synthase orthologs.

    Science.gov (United States)

    Lentz, Christian S; Halls, Victoria S; Hannam, Jeffrey S; Strassel, Silke; Lawrence, Sarah H; Jaffe, Eileen K; Famulok, Michael; Hoerauf, Achim; Pfarr, Kenneth M

    2014-03-27

    The heme biosynthesis enzyme porphobilinogen synthase (PBGS) is a potential drug target in several human pathogens. wALADin1 benzimidazoles have emerged as species-selective PBGS inhibitors against Wolbachia endobacteria of filarial worms. In the present study, we have systematically tested wALADins against PBGS orthologs from bacteria, protozoa, metazoa, and plants to elucidate the inhibitory spectrum. However, the effect of wALADin1 on different PBGS orthologs was not limited to inhibition: several orthologs were stimulated by wALADin1; others remained unaffected. We demonstrate that wALADins allosterically modulate the PBGS homooligomeric equilibrium with inhibition mediated by favoring low-activity oligomers, while 5-aminolevulinic acid, Mg(2+), or K(+) stabilized high-activity oligomers. Pseudomonas aeruginosa PBGS could be inhibited or stimulated by wALADin1 depending on these factors and pH. We have defined the wALADin chemotypes responsible for either inhibition or stimulation, facilitating the design of tailored PBGS modulators for potential application as antimicrobial agents, herbicides, or drugs for porphyric disorders.

  14. Benzimidazole resistance of sheep nematodes in Norway confirmed through controlled efficacy test

    Directory of Open Access Journals (Sweden)

    Domke Atle V

    2012-08-01

    Full Text Available Abstract Background Resistance against benzimidazoles (BZ has recently been detected in Norwegian sheep flocks through a large scale prevalence survey based on the faecal egg count reduction test (FECRT. The use of this test in combination with bulk larval culture only gives an indication of which gastrointestinal nematodes genera that are involved and these results have to be confirmed by a controlled efficacy test (CET to get accurate information about resistant nematodes populations at species level. A CET was therefore performed with larvae from two flocks where BZ resistance was previously detected through FECRT. Results The latter test confirmed the previous results in both flocks. In flock A, the BZ resistant nematode population consisted solely of Haemonchus contortus, whereas H. contortus and Teladorsagia circumcincta comprised the resistant worm population in flock B. Conclusions Some discrepancies that have been recorded between FECRT and CET results regarding time for post-treatment coproscopical examination and a temporary suppression of faecal egg excretion are discussed.

  15. 2-(2-Pyridyl) Benzimidazole Analogs and their beta-Glucuronidase Inhibitory Activity

    International Nuclear Information System (INIS)

    Kamil, A.; Noureen, S.

    2015-01-01

    Synthesis of 2-(2-Pyridyl) benzimidazole analogs 1-11 have been carried out and evaluated for in vitro beta-glucuronidase inhibitory potential. The compounds 4 (IC/sub 50/ = 4.06 ± 0.34 meuM), 5 (IC/sub 50/ = 09.63 ± 0.81 meuM), 1 (IC/sub 50/ = 19.66 ± 0.44 meuM), 7 (IC/sub 50/ = 24.75 ± 0.25 meuM), 6 (IC/sub 50/ = 26.30 ± 1.37 meuM), and 3 (IC/sub 50/ = 32.11 ± 0.89 meuM), showed beta-glucuronidase inhibitory activity superior to the standard D-saccharic acid 1,4-lactone, with (IC/sub 50/ = 48.4 ± 1.25 meuM). Based on structure-activity relationship, we discover a new class of potent beta-glucuronidase inhibitors. (author)

  16. Blocking of valinomycin-mediated bilayer membrane conductance by substituted benzimidazoles.

    Science.gov (United States)

    Kuo, K H; Fukuto, T R; Miller, T A; Bruner, L J

    1976-01-01

    Valinomycin selectively transports alkali cations, e.g. potassium ions, across lipid bilayer membranes. The blocking of this carrier-mediated transport by four substituted benzimidazoles has been investigated. The compounds are 4,5,6,7-tetrachloro-2-trifluoromethylbenzimidazole, (TTFB); 4,5,6,7,-tetrachloro-2-methylbenzimidazole, (TMB); 2-trifluoromethylbenzimidazole, (TFB); and 2-methylbenzimidazole, (MBM). Because of its low acidic dissociation constant (pKa = 5.04), the blocking efficiency of TTFB in both neutral and anionic forms in the aqueous phase could be studied. The compounds exhibit the blocking efficiency sequence, TTFB- greater than TTFB0 greater than TMB0 greater than TFB0 greater than MBM0. The corresponding scale of decreasing lipophilicity, as determined by octanol/water partitioning, is TTFB0 greater than TMB0 greater than TTFB- greater than TFB0 greater than MBM0. Comparison of neutral species establishes a positive correlation of blocking efficiency with lipophilicity, with the latter being conferred primarily by chlorination of the benzenoid nucleus. Anionic TTFB, on the other hand, is the most effective blocking agent studied in spite of the fact that its dissociation in the aqueous phase markedly impedes its entry (presumably as a neutral species) into a bulk hydrocarbon phase. This observation suggests that the blocking of valinomycin-mediated bilayer membrane conductance takes place at the membrane/solution interface. PMID:1247644

  17. Structural investigation of HIV-1 nonnucleoside reverse transcriptase inhibitors: 2-Aryl-substituted benzimidazoles

    Science.gov (United States)

    Ziółkowska, Natasza E.; Michejda, Christopher J.; Bujacz, Grzegorz D.

    2009-11-01

    Acquired immunodeficiency syndrome (AIDS) caused by the human immunodeficiency virus (HIV) is one of the most destructive epidemics in history. Inhibitors of HIV enzymes are the main targets to develop drugs against that disease. Nonnucleoside reverse transcriptase inhibitors of HIV-1 (NNRTIs) are potentially effective and nontoxic. Structural studies provide information necessary to design more active compounds. The crystal structures of four NNRTI derivatives of 2-aryl-substituted N-benzyl-benzimidazole are presented here. Analysis of the geometrical parameters shows that the structures of the investigated inhibitors are rigid. The important geometrical parameter is the dihedral angle between the planes of the π-electron systems of the benzymidazole and benzyl moieties. The values of these dihedral angles are in a narrow range for all investigated inhibitors. There is no significant difference between the structure of the free inhibitor and the inhibitor in the complex with RT HIV-1. X-ray structures of the investigated inhibitors are a good basis for modeling enzyme-inhibitor interactions in rational drug design.

  18. Genetic Analysis of Resistance to Benzimidazoles in Physarum: Differential Expression of β-Tubulin Genes

    Science.gov (United States)

    Burland, Timothy G.; Schedl, Tim; Gull, Keith; Dove, William F.

    1984-01-01

    Physarum displays two vegetative cell types, uninucleate myxamoebae and multinucleate plasmodia. Mutant myxamoebae of Physarum resistant to the antitubulin drug methylbenzimidazole-2-yl-carbamate (MBC) were isolated. All mutants tested were cross-resistant to other benzimidazoles but not to cycloheximide or emetine. Genetic analysis showed that mutation to MBC resistance can occur at any one of four unlinked loci, benA, benB, benC or benD. MBC resistance of benB and benD mutants was expressed in plasmodia, but benA and benC mutant plasmodia were MBC sensitive, suggesting that benA and benC encode myxamoeba-specific products. Myxamoebae carrying the recessive benD210 mutation express a β-tubulin with noval electrophoretic mobility, in addition to a β-tubulin with wild-type mobility. This and other evidence indicates that benD is a structural gene for β-tubulin, and that at least two β-tubulin genes are expressed in myxamoebae. Comparisons of the β-tubulins of wildtype and benD210 strains by gel electrophoresis revealed that, of the three (or more) β-tubulin genes expressed in Physarum, one, benD, is expressed in both myxamoebae and plasmodia, one is expressed specifically in myxamoebae and one is expressed specifically in plasmodia. However, mutation in only one gene, benD, is sufficient to confer MBC resistance on both myxamoebae and plasmodia. PMID:6479584

  19. Synthesis and potential cytotoxic activity of some new benzoxazoles, imidazoles, benzimidazoles and tetrazoles.

    Science.gov (United States)

    Arulmurugan, Subramaniyan; Kavitha, Helen P

    2013-06-01

    2 The present work deals with the synthesis of some novel heterocyclic compounds such as benzoxazoles , 7, 13 and 19, imidazoles 3, 8, 14 and 20, benzimidazoles 4, 9, 15 and 21, and tetrazoles 10, 16, and 22. The synthesized compounds were characterized by IR, 1H NMR, mass spectrometry and elemental analysis. The compounds were evaluated for cytotoxicity against human cancer cell lines such as MCF-7 (breast cancer) and HT-29 (colon cancer) by the MTT assay method. Among the tested compounds, 4,4'-sulfonylbis(N-(2-(1H-benzo[d]imidazol- -2-yl)ethyl)aniline (9), N-bis(2-(benzo[d]oxazol-2-yl)-ethyl)- 6-phenyl-1,3,5-triazine-2,4-diamine (13), N-bis(2-(1H-benzo[ d]imidazol-2-yl)ethyl)-6-phenyl-1,3,5-triazine-2,4-diamine (15) and N-tris(2-1H-benzo[d]imidazol-2-yl)ethyl)- 1,3,5-triazine-2,4,6-triamine (21) showed potent cytotoxicity.

  20. Estimation of the cost of large-scale school deworming programmes with benzimidazoles

    Science.gov (United States)

    Montresor, A.; Gabrielli, A.F.; Engels, D.

    2017-01-01

    Summary This study estimates the cost of distributing benzimidazole tablets in the context of school deworming programmes: we analysed studies reporting the cost of school deworming from seven countries in four WHO regions. The estimated cost for drug procurement to cover one million children (including customs clearance and international transport) is approximately US$20 000. The estimated financial costs (including the cost of training of personnel, drug transport, social mobilization and monitoring) is, on average, equivalent to US$33 000 per million school-age children with minimal variation in different countries and continents. The estimated economic costs of distribution (including the time spent by teachers, and health personnel at central, provincial and district level) to cover one million children approximately corresponds to US$19 000. This study shows the minimal cost of school deworming activities, but also shows the significant contribution (corresponding to a quarter of the entire cost of the programme) provided by health and education systems in endemic countries even in the case of drug donations and donor support of distribution costs. PMID:19926104

  1. Recent Advances in Target Characterization and Identification by Photoaffinity Probes

    Directory of Open Access Journals (Sweden)

    Sang J. Chung

    2013-08-01

    Full Text Available Target identification of biologically active molecules such as natural products, synthetic small molecules, peptides, and oligonucleotides mainly relies on affinity chromatography, activity-based probes, or photoaffinity labeling (PAL. Amongst them, activity-based probes and PAL have offered great advantages in target identification technology due to their ability to form covalent bonds with the corresponding targets. Activity-based probe technology mainly relies on the chemical reactivity of the target proteins, thereby limiting the majority of the biological targets to enzymes or proteins which display reactive residues at the probe-binding site. In general, the probes should bear a reactive moiety such as an epoxide, a Michael acceptor, or a reactive alkyl halide in their structures. On the other hand, photoaffinity probes (PAPs are composed of a target-specific ligand and a photoactivatable functional group. When bound to the corresponding target proteins and activated with wavelength-specific light, PAPs generate highly reactive chemical species that covalently cross-link proximal amino acid residues. This process is better known as PAL and is widely employed to identify cellular targets of biologically active molecules. This review highlights recent advances in target identification by PAL, with a focus on the structure and chemistry of the photoaffinity probes developed in the recent decade, coupled to the target proteins identified using these probes.

  2. Donated chemical probes for open science.

    Science.gov (United States)

    Müller, Susanne; Ackloo, Suzanne; Arrowsmith, Cheryl H; Bauser, Marcus; Baryza, Jeremy L; Blagg, Julian; Böttcher, Jark; Bountra, Chas; Brown, Peter J; Bunnage, Mark E; Carter, Adrian J; Damerell, David; Dötsch, Volker; Drewry, David H; Edwards, Aled M; Edwards, James; Elkins, Jon M; Fischer, Christian; Frye, Stephen V; Gollner, Andreas; Grimshaw, Charles E; IJzerman, Adriaan; Hanke, Thomas; Hartung, Ingo V; Hitchcock, Steve; Howe, Trevor; Hughes, Terry V; Laufer, Stefan; Li, Volkhart Mj; Liras, Spiros; Marsden, Brian D; Matsui, Hisanori; Mathias, John; O'Hagan, Ronan C; Owen, Dafydd R; Pande, Vineet; Rauh, Daniel; Rosenberg, Saul H; Roth, Bryan L; Schneider, Natalie S; Scholten, Cora; Singh Saikatendu, Kumar; Simeonov, Anton; Takizawa, Masayuki; Tse, Chris; Thompson, Paul R; Treiber, Daniel K; Viana, Amélia Yi; Wells, Carrow I; Willson, Timothy M; Zuercher, William J; Knapp, Stefan; Mueller-Fahrnow, Anke

    2018-04-20

    Potent, selective and broadly characterized small molecule modulators of protein function (chemical probes) are powerful research reagents. The pharmaceutical industry has generated many high-quality chemical probes and several of these have been made available to academia. However, probe-associated data and control compounds, such as inactive structurally related molecules and their associated data, are generally not accessible. The lack of data and guidance makes it difficult for researchers to decide which chemical tools to choose. Several pharmaceutical companies (AbbVie, Bayer, Boehringer Ingelheim, Janssen, MSD, Pfizer, and Takeda) have therefore entered into a pre-competitive collaboration to make available a large number of innovative high-quality probes, including all probe-associated data, control compounds and recommendations on use (https://openscienceprobes.sgc-frankfurt.de">https://openscienceprobes.sgc-frankfurt.dehttps://openscienceprobes.sgc-frankfurt.de/">/). Here we describe the chemical tools and target-related knowledge that have been made available, and encourage others to join the project. © 2018, Müller et al.

  3. Sensing single electrons with single molecules

    International Nuclear Information System (INIS)

    Plakhotnik, Taras

    2007-01-01

    We propose a new methodology for probing transport of just one electron, a process of great importance both in nature and in artificial devices. Our idea for locating a single electron is analogues to the conventional GPS where signals from several satellites are used to locate a macro object. Using fluorescent molecules as tiny sensors, it is possible to determine 3D displacement vector of an electron

  4. Synthesis of novel synthetic intermediates from the reaction of benzimidazole and triazole carbenes with ketenimines and their application in the construction of spiro-pyrroles.

    Science.gov (United States)

    Mo, Jun-Ming; Ma, Yang-Guang; Cheng, Ying

    2009-12-07

    2-(2-Alkoxycarbonyl-1-arylamino-1-propenyl)benzimidazolium and 5-(2-alkoxycarbonyl-1-arylamino-1-propenyl)triazolium salts were synthesized in good yields from the reaction of benzimidazole and triazole carbenes with ketenimines. Upon treatment with a base, both salts were converted into novel 1,3-dipoles which underwent [3+2] cycloaddition reactions with electron-deficient alkynes and allenes to produce benzimidazole-spiro-pyrroles or triazole-spiro-pyrroles. This work provides novel synthons for the construction of multifunctional spiro-pyrrole derivatives that are not easy accessible by other synthetic methods and are potentially amenable to further transformations.

  5. Highly efficient water-mediated approach to access benzazoles: metal catalyst and base-free synthesis of 2-substituted benzimidazoles, benzoxazoles, and benzothiazoles.

    Science.gov (United States)

    Bala, Manju; Verma, Praveen Kumar; Sharma, Deepika; Kumar, Neeraj; Singh, Bikram

    2015-05-01

    An efficient water-catalyzed method has been developed for the synthesis of 2-substituted benzimidazoles, benzoxazoles, and benzothiazoles in one step. The present method excludes the usage of toxic metal catalysts and bases to produce benzazoles in good to excellent yields. An efficient and versatile water-mediated method has been established for the synthesis of various 2-arylbenzazoles. The present protocol excludes the usage of any catalyst and additive provided excellent selectivities and yields with high functional group tolerance for the synthesis of 2-arylated benzimidazoles, benzoxazoles, and benzothiazoles. Benzazolones were also synthesized using similar reaction protocol.

  6. Complexes cobalt(II, zinc(II and copper(II with some newly synthesized benzimidazole derivatives and their antibacterial activity

    Directory of Open Access Journals (Sweden)

    S. O. PODUNAVAC-KUZMANOVIC

    1999-05-01

    Full Text Available The preparation and properties of some complexes of cobalt(II, zinc(II and copper(II with several newly synthesized benzimidazole derivatives (L are reported. The complexes, of the general formula [MCl2L2] (M=Co(II, Zn(II and [CuCl2L(H2O], have a tetrahedral structure. The complexes were characterized by elemental analysis, molar conductivity, magnetic susceptibility measurements, IR and absorption electronic spectra. The antibacterial activitiy of the benzimidazoles and their complexes was evaluated against Erwinia carotovora subsp. carotovora and Erwinia amylovora. The complexes were found to be more toxic than the ligands.

  7. Probe-diverse ptychography

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, I., E-mail: isaac.russellpeterson@rmit.edu.au [ARC Centre of Excellence for Coherent X-ray Science, the University of Melbourne, School of Physics, Victoria 3010 (Australia); Harder, R. [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Robinson, I.K. [Research Complex at Harwell, Didcot, Oxfordshire OX11 0DE (United Kingdom); London Centre for Nanotechnology, University College London, London WC1H 0AH (United Kingdom)

    2016-12-15

    We propose an extension of ptychography where the target sample is scanned separately through several probes with distinct amplitude and phase profiles and a diffraction image is recorded for each probe and each sample translation. The resulting probe-diverse dataset is used to iteratively retrieve high-resolution images of the sample and all probes simultaneously. The method is shown to yield significant improvement in the reconstructed sample image compared to the image obtained using the standard single-probe ptychographic phase-retrieval scheme.

  8. Traversing probe system

    International Nuclear Information System (INIS)

    Mashburn, D.N.; Stevens, R.H.; Woodall, H.C.

    1977-01-01

    This invention comprises a rotatable annular probe-positioner which carries at least one radially disposed sensing probe, such as a Pitot tube having a right-angled tip. The positioner can be coaxially and rotatably mounted within a compressor casing or the like and then actuated to orient the sensing probe as required to make measurements at selected stations in the annulus between the positioner and compressor casing. The positioner can be actuated to (a) selectively move the probe along its own axis, (b) adjust the yaw angle of the right-angled probe tip, and (c) revolve the probe about the axis common to the positioner and casing. A cam plate engages a cam-follower portion of the probe and normally rotates with the positioner. The positioner includes a first-motor-driven ring gear which effects slidable movement of the probe by rotating the positioner at a time when an external pneumatic cylinder is actuated to engage the cam plate and hold it stationary. When the pneumatic cylinder is not actuated, this ring gear can be driven to revolve the positioner and thus the probe to a desired circumferential location about the above-mentioned common axis. A second motor-driven ring gear included in the positioner can be driven to rotate the probe about its axis, thus adjusting the yaw angle of the probe tip. The positioner can be used in highly corrosive atmosphere, such as gaseous uranium hexafluoride. 10 claims, 6 figures

  9. Traversing probe system

    Science.gov (United States)

    Mashburn, Douglas N.; Stevens, Richard H.; Woodall, Harold C.

    1977-01-01

    This invention comprises a rotatable annular probe-positioner which carries at least one radially disposed sensing probe, such as a Pitot tube having a right-angled tip. The positioner can be coaxially and rotatably mounted within a compressor casing or the like and then actuated to orient the sensing probe as required to make measurements at selected stations in the annulus between the positioner and compressor casing. The positioner can be actuated to (a) selectively move the probe along its own axis, (b) adjust the yaw angle of the right-angled probe tip, and (c) revolve the probe about the axis common to the positioner and casing. A cam plate engages a cam-follower portion of the probe and normally rotates with the positioner. The positioner includes a first-motor-driven ring gear which effects slidable movement of the probe by rotating the positioner at a time when an external pneumatic cylinder is actuated to engage the cam plate and hold it stationary. When the pneumatic cylinder is not actuated, this ring gear can be driven to revolve the positioner and thus the probe to a desired circumferential location about the above-mentioned common axis. A second motor-driven ring gear included in the positioner can be driven to rotate the probe about its axis, thus adjusting the yaw angle of the probe tip. The positioner can be used in highly corrosive atmosphere, such as gaseous uranium hexafluoride.

  10. A Practical Green Synthesis and Biological Evaluation of Benzimidazoles Against Two Neglected Tropical Diseases: Chagas and Leishmaniasis.

    Science.gov (United States)

    Bandyopadhyay, Debashis; Samano, Selina; Villalobos-Rocha, Juan Carlos; Sanchez-Torres, Luvia Enid; Nogueda-Torres, Benjamin; Rivera, Gildardo; Banik, Bimal K

    2017-01-01

    Antimicrobial resistance is an ever-increasing problem throughout the world and has already reached severe proportions. Two very common neglected tropical diseases are Chagas' disease and leishmaniasis. Chagas' disease is a severe health problem, mainly in Latin America, causing approximately 50000 deaths a year and millions of people are infected. About 25-30% of the patients infected with Trypanosoma cruzi develop the chronic form of the disease. On the other hand, Leishmaniasis represents complex diseases with an important clinical and epidemiological diversity. It is endemic in 88 countries 72 of which are developing countries and it has been estimated that are 12 million people infected and 350 million are in areas with infection risk. On this basis, research on organic compounds that can be used against these two diseases is an important target. A very simple, green, and efficient protocol is developed in which bismuth nitrate pentahydrate is employed as a Lewis acid catalyst in aqueous media under microwave irradiation for the synthesis of various 2-aryl substituted benzimidazoles from aldehydes and o-phenylenediamine. Other salient features of this protocol include milder conditions, atom-economy, easy extraction, and no wastes. Nine 1H-benzimidazole derivatives (1-9) with substituents at positions 2 and 5 were synthesized and the structure of the compounds was elucidated by spectroscopic methods. The compounds were screened to identify whether they posses pharmacological activity against Chagas' disease and leishmaniasis. Compound 8 showed better activity than the control Nifurtimox against INC-5 Trypanosoma cruzi strain whereas compounds 3 and 9 have demonstrated potent leshmanicidal activity. A systematic green synthetic procedure and in vitro biological evaluation of nine 1H-benzimidazoles are described. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  11. Aromatic carboxylate effect on dimensionality of three bis(benzimidazole)-based cobalt(II) coordination polymers: Syntheses, structures and properties

    International Nuclear Information System (INIS)

    Zhang, Ju-Wen; Gong, Chun-Hua; Hou, Li-Li; Tian, Ai-Xiang; Wang, Xiu-Li

    2013-01-01

    Three new metal-organic coordination polymers [Co(4-bbc) 2 (bbbm)] (1), [Co(3,5-pdc)(bbbm)]·2H 2 O (2) and [Co(1,4-ndc)(bbbm)] (3) (4-Hbbc=4-bromobenzoic acid, 3,5-H 2 pdc=3,5-pyridinedicarboxylic acid, 1,4-H 2 ndc=1,4-naphthalenedicarboxylic acid and bbbm=1,1-(1,4-butanediyl)bis-1H-benzimidazole) were hydrothermally synthesized and structurally characterized. Polymer 1 is a 1D chain formed by the bbbm ligands and Co II ions. Polymer 2 exhibits a 2D network with a (3·4·5)(3 2 ·4·5·6 2 ·7 4 ) topology. Polymer 3 possesses a 3D three-fold interpenetrating framework. The versatile structures of title polymers indicate that the aromatic carboxylates have an important influence on the dimensionality of 1–3. Moreover, the thermal stability, electrochemical and luminescent properties of 1–3 were investigated. - graphical abstract: Three bis(benzimidazole)-based cobalt(II) coordination polymers tuned by aromatic carboxylates were hydrothermally synthesized and structurally characterized. The aromatic carboxylates play a key role in the dimensionality of three polymers. The electrochemical and luminescent properties of three polymers were investigated. Display Omitted - Highlights: • Three bis(benzimidazole)-based cobalt(II) coordination polymers tuned by aromatic carboxylates were obtained. • The aromatic carboxylates have an important influence on the dimensionality of three polymers. • The electrochemical and luminescent properties of three polymers were investigated

  12. Determination of benzimidazoles in meat samples by capillary zone electrophoresis tandem mass spectrometry following dispersive liquid-liquid microextraction.

    Science.gov (United States)

    Tejada-Casado, Carmen; Moreno-González, David; Lara, Francisco J; García-Campaña, Ana M; Del Olmo-Iruela, Monsalud

    2017-03-24

    A novel method based on capillary zone electrophoresis-tandem mass spectrometry has been proposed and validated for the identification and simultaneous quantification of twelve benzimidazoles in meat samples. Electrophoretic separation was carried out using 500mM formic acid (pH 2.2) as background electrolyte and applying a voltage of 25kV at 25°C. In order to improve the sensitivity, stacking mode injection was applied, using as injection solvent a mixture of 30:70 acetonitrile/water at 50mbar for 75s. Sensitivity enhancement factors from 74 to 317 were obtained under these conditions. Detection using an ion trap as analyzer, operating in multiple reactions monitoring mode was employed. The main MS/MS parameters as well as the composition of the sheath liquid and other electrospray variables were optimized in order to obtain the highest sensitivity and precision in conjunction with an unequivocal identification. The method was applied to poultry and pork muscle samples. The deproteinization of samples and extraction of benzimidazoles was carried out with acetonitrile. MgSO 4 and NaCl were added as salting-out agents. Subsequently, dispersive liquid-liquid microextraction was applied as clean up procedure. The organic layer (acetonitrile, used as dispersant) containing the benzimidazoles was mixed with the extractant (chloroform) and both were injected in water, producing a cloudy solution. Recoveries for fortified samples were higher than 70%, with relative standard deviations lower than 16% were obtained in all cases. The limits of detection were below 3μgkg -1 , demonstrating the applicability of this fast, simple, and environmentally friendly method. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Electrical resistivity probes

    Science.gov (United States)

    Lee, Ki Ha; Becker, Alex; Faybishenko, Boris A.; Solbau, Ray D.

    2003-10-21

    A miniaturized electrical resistivity (ER) probe based on a known current-voltage (I-V) electrode structure, the Wenner array, is designed for local (point) measurement. A pair of voltage measuring electrodes are positioned between a pair of current carrying electrodes. The electrodes are typically about 1 cm long, separated by 1 cm, so the probe is only about 1 inch long. The electrodes are mounted to a rigid tube with electrical wires in the tube and a sand bag may be placed around the electrodes to protect the electrodes. The probes can be positioned in a borehole or on the surface. The electrodes make contact with the surrounding medium. In a dual mode system, individual probes of a plurality of spaced probes can be used to measure local resistance, i.e. point measurements, but the system can select different probes to make interval measurements between probes and between boreholes.

  14. Design, synthesis and biological activity of 6-substituted carbamoyl benzimidazoles as new nonpeptidic angiotensin II AT₁ receptor antagonists.

    Science.gov (United States)

    Zhang, Jun; Wang, Jin-Liang; Zhou, Zhi-Ming; Li, Zhi-Huai; Xue, Wei-Zhe; Xu, Di; Hao, Li-Ping; Han, Xiao-Feng; Fei, Fan; Liu, Ting; Liang, Ai-Hua

    2012-07-15

    A series of 6-substituted carbamoyl benzimidazoles were designed and synthesised as new nonpeptidic angiotensin II AT(1) receptor antagonists. The preliminary pharmacological evaluation revealed a nanomolar AT(1) receptor binding affinity for all compounds in the series, and a potent antagonistic activity in an isolated rabbit aortic strip functional assay for compounds 6f, 6g, 6h and 6k was also demonstrated. Furthermore, evaluation in spontaneous hypertensive rats and a preliminary toxicity evaluation showed that compound 6g is an orally active AT(1) receptor antagonist with low toxicity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. A Bioinspired Catalytic Aerobic Oxidative C–H Functionalization of Primary Aliphatic Amines: Synthesis of 1,2-Disubstituted Benzimidazoles

    Science.gov (United States)

    Nguyen, Khac Minh Huy; Largeron, Martine

    2015-01-01

    Aerobic oxidative C–H functionalization of primary aliphatic amines has been accomplished with a biomimetic cooperative catalytic system to furnish 1,2-disubstituted benzimidazoles that play an important role as drug discovery targets. This one-pot atom-economical multistep process, which proceeds under mild conditions, with ambient air and equimolar amounts of each coupling partner, constitutes a convenient environmentally friendly strategy to functionalize non-activated aliphatic amines that remain challenging substrates for non-enzymatic catalytic aerobic systems. PMID:26206475

  16. A convergent approach to the total synthesis of telmisartan via a Suzuki cross-coupling reaction between two functionalized benzimidazoles.

    Science.gov (United States)

    Martin, Alex D; Siamaki, Ali R; Belecki, Katherine; Gupton, B Frank

    2015-02-06

    A direct and efficient total synthesis has been developed for telmisartan, a widely prescribed treatment for hypertension. This approach brings together two functionalized benzimidazoles using a high-yielding Suzuki reaction that can be catalyzed by either a homogeneous palladium source or graphene-supported palladium nanoparticles. The ability to perform the cross-coupling reaction was facilitated by the regio-controlled preparation of the 2-bromo-1-methylbenzimidazole precursor. This convergent approach provides telmisartan in an overall yield of 72% while circumventing many issues associated with previously reported processes.

  17. Preparation, characterization and catalytic application of CoFe2O4 nanoparticles in the synthesis of benzimidazoles

    Science.gov (United States)

    Borade, Ravikumar M.; Shinde, Pavan R.; Kale, Swati B.; Pawar, Rajendra P.

    2018-05-01

    A highly efficient magnetically recoverable cobalt ferrite nano-catalyst was prepared by sol-gel autocombustion method using glycine as green fuel. The prepared material has been characterized by X-ray powder diffraction and scanning. An investigation of its catalytic activity showed it to be a heterogeneous Lewis acid catalyst for the synthesis of substituted benzimidazoles. The aqueous ethanol used as green solvent for the reaction. The nm size range of these particles facilitates the catalysis process, as an increased surface area available for the reaction. The easy separation of the catalyst by an external magnet and their recovery and reuse in next cycle reaction are additional benefits.

  18. Solvent/oxidant-switchable synthesis of multisubstituted quinazolines and benzimidazoles via metal-free selective oxidative annulation of arylamidines.

    Science.gov (United States)

    Lin, Jian-Ping; Zhang, Feng-Hua; Long, Ya-Qiu

    2014-06-06

    A fast and simple divergent synthesis of multisubstituted quinazolines and benzimidazoles was developed from readily available amidines, via iodine(III)-promoted oxidative C(sp(3))-C(sp(2)) and C(sp(2))-N bond formation in nonpolar and polar solvents, respectively. Further selective synthesis of quinazolines in polar solvent was realized by TEMPO-catalyzed sp(3)C-H/sp(2)C-H direct coupling of the amidine with K2S2O8 as the oxidant. No metal, base, or other additives were needed.

  19. Efficient FeCl3/SiO2 as heterogeneous nanocatalysis for the synthesis of benzimidazoles under mild conditions

    Science.gov (United States)

    Taher, Mohammad Ali; Karami, Changiz; Arabi, Mehdi Sheikh; Ahmadian, Hossein; Karami, Yasaman

    2016-11-01

    Iron(III) supported on nano silica as a new catalyst has been synthesized. Structural properties of this complex have been studied by TEM, SEM and EDX. The average crystalline size of Iron(III) supported on nano silica is 30-50 nm. Catalytic activity of this catalyst has been investigated by synthesis of benzimidazoles from 1, 2-diaminobenzene and aromatic aldehydes, and also the other variables investigated such as the amount of catalyst, reaction temperature and the effect of various solvents are also studied. The present procedure offers several advantages such as short reaction time, simple workup, recovery and reusability of the catalyst.

  20. Proton-transfer lasers based on solid copolymers of modified 2-(2'-hydroxyphenyl)benzimidazoles with methacrylate monomers

    Science.gov (United States)

    Costela, A.; García-Moreno, I.; Mallavia, Ricardo; Amat-Guerri, F.; Barroso, J.; Sastre, R.

    1998-06-01

    We report on the lasing action of two newly synthesized 2-(2'-hydroxyphenyl) benzimidazole derivatives copolymerized with methyl methacrylate. The laser samples were transversely pumped with a N 2 laser at 337 nm. The influence on the proton-transfer laser performance of the distance between the chromophore group and the polymeric main chain and of the rigidity of the polymeric host matrix, were studied. Significant increases in lasing efficiency and photostability are demonstrated for some of the new materials, as compared to those previously obtained with related proton-transfer dyes also covalently bound to methacrylic monomers.