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Li S, Zhang X, Zhao T, Liu N, Zhang Y, Wang P, Yang Z, Huhn T. Synthesis, in vitro antitumor evaluation and structure activity relationship of heptacoordinated amino-bis(Phenolato) Ti(IV) complexes stabilized by 2,6-dipicolinic acid. J Biol Inorg Chem 2024; 29:315-330. [PMID: 38722397 DOI: 10.1007/s00775-024-02059-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 02/22/2024] [Indexed: 05/24/2024]
Abstract
Eighteen novel Ti(IV) complexes stabilized by different chelating amino-bis(phenolato) (ONNO, ONON, ONOO) ligands and 2,6-dipicolinic acid as a second chelator were synthesized with isolated yields ranging from 79 to 93%. Complexes were characterized by 1H and 13C-NMR spectroscopy, as well as by HRMS and X-Ray diffraction analysis. The good to excellent aqueous stability of these Ti(IV) complexes can be modulated by the substitutions on the 2-position of the phenolato ligands. Most of the synthesized Ti(IV) complexes demonstrated potent inhibitory activity against Hela S3 and Hep G2 tumor cells. Among them, the naphthalenyl based Salan type 2j, 2-picolylamine based [ONON] type 2n and N-(2-hydroxyethyl) based [ONOO] type 2p demonstrated up to 40 folds enhanced cytotoxicity compared to cisplatin together with a significantly reduced activity against healthy AML12 cells. The three Ti(IV) complexes exhibited fast cellular uptake by Hela S3 cells and induced almost exclusively apoptosis. 2j could trigger higher level of ROS generation than 2p and 2n.
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Affiliation(s)
- Shanjia Li
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, People's Republic of China
| | - Xupeng Zhang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, People's Republic of China
| | - Tiankun Zhao
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, People's Republic of China.
| | - Nan Liu
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, People's Republic of China
| | - Yong Zhang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, People's Republic of China
| | - Peng Wang
- School of Chemistry, Sun Yat-Sen University, Guangzhou, 510006, People's Republic of China
| | - Zhongduo Yang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, People's Republic of China
| | - Thomas Huhn
- Fachbereich Chemie, Universität Konstanz, Universitätsstr. 10, 78457, Konstanz, Germany.
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Snegir S, Dappe YJ, Sysoiev D, Huhn T, Scheer E. Nonuniform STM Contrast of Self-Assembled Tri- n-octyl-triazatriangulenium Tetrafluoroborate on HOPG. ACS Omega 2023; 8:38766-38772. [PMID: 37867726 PMCID: PMC10586247 DOI: 10.1021/acsomega.3c06454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 09/21/2023] [Indexed: 10/24/2023]
Abstract
We have assembled 4,8,12-tri-n-octyl-4,8,12-triazatrianguleniumtetrafluoroborate (TATA-BF4) on highly oriented pyrolytic graphite (HOPG) and have studied the structure and tunneling properties of this self-assembled monolayer (SAM) using scanning tunneling microscopy (STM) under ambient conditions. We show that the triazatriangulenium cations TATA+ form hexagonally packed structures driven by the interaction between the aromatic core and the HOPG lattice, as evidenced by density functional theory (DFT) modeling. According to the DFT results, the three alkyl chains of the platform tend to follow the main crystallographic directions of HOPG, leading to a different STM appearance. The STM contrast of the SAM shows that the monolayer is formed by two types of species, namely, TATA+ with BF4- counterions on top and without them. The cationic TATA+ platform gives rise to a seemingly higher appearance than neutral TATA-BF4, in contrast to observations made on metallic substrates. The variation of the STM tunneling parameters does not change the relative difference of contrast, revealing the stability of both species on HOPG. DFT calculations show that TATA-BF4 on HOPG has sufficient binding energy to resist dissociation into TATA+ and BF4-, which might occur under the action of the electric field in the tunneling gap during STM scanning.
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Affiliation(s)
- Sergii Snegir
- Department
of Physics, University of Konstanz, Universitätsstraße 10, Konstanz 78464, Germany
| | - Yannick J. Dappe
- SPEC,
CEA, CNRS, Université Paris-Saclay, CEA Saclay, Gif-sur-Yvette Cédex 91191, France
| | - Dmytro Sysoiev
- Department
of Chemistry, University of Konstanz, Universitätsstraße 10, Konstanz 78464, Germany
| | - Thomas Huhn
- Department
of Chemistry, University of Konstanz, Universitätsstraße 10, Konstanz 78464, Germany
| | - Elke Scheer
- Department
of Physics, University of Konstanz, Universitätsstraße 10, Konstanz 78464, Germany
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3
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Zhao T, Wang P, Liu N, Zhao W, Yang M, Li S, Yang Z, Sun B, Huhn T. Synthesis and X-ray structure analysis of cytotoxic heptacoordinated Salan hafnium (IV) complexes stabilized with 2,6-dipicolinic acid. J Inorg Biochem 2023; 240:112094. [PMID: 36525714 DOI: 10.1016/j.jinorgbio.2022.112094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 11/13/2022] [Accepted: 12/04/2022] [Indexed: 12/13/2022]
Abstract
Four novel Salan Hf(IV) complexes stabilized by 2,6-dipicolinic acid (Dipic) were synthesized and characterized by 1H, 13C NMR and X-ray diffraction spectroscopy. These Hf(IV)bis-chelates could be obtained in good to excellent yields (88%-91%) and demonstrated rather good stability in aqueous media and on silica gel. [L2Hf(IV)Dipic4-H,Cl] containing steric bulk L2 were stable in about 10% H2O (H2O/THF (v/v)), however, [L1Hf(IV)Dipic4-H,Cl] with non-steric L1 could slowly dissociate and release nontoxic L1. [L1-2Hf(IV)Dipic4-Cl] showed excellent anti-tumoral activity in the range of cisplatin (Hela S3: IC50 = 3.5 ± 0.4 μM, Hep G2: IC50 = 11.2 ± 2.1 μM). In addition, the cellular uptake and apoptosis investigation of [L1Hf(IV)Dipic4-Cl] suggested a fast cellular uptake process against Hela S3 cells with an almost exclusive induced apoptosis cell death path.
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Affiliation(s)
- Tiankun Zhao
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China.
| | - Peng Wang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Nan Liu
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Wenzhuo Zhao
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Mingjun Yang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Shanjia Li
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Zhongduo Yang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Bolu Sun
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Thomas Huhn
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany
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Zhao T, Wang P, Zhang X, Liu N, Zhao W, Zhang Y, Yuan P, Li S, Yang M, Yang Z, Huhn T. Anti-tumoral Titanium (IV) Complexes Stabilized with Phenolato Ligands and Structure-Activity Relationship. Curr Top Med Chem 2023; 23:1835-1849. [PMID: 37151173 DOI: 10.2174/1568026623666230505104626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 03/19/2023] [Accepted: 03/21/2023] [Indexed: 05/09/2023]
Abstract
Titanocene dichloride and budotitane have opened a new chapter in medicinal chemistry of titanium(IV) complexes being novel non-platinum antitumor metallic agents. Numerous efforts have led to the discovery of the diamino bis-phenolato titanium(IV) complexes. Among which, the [ONNO] and [ONON] type ligands namely Salan, Salen and Salalen coordinated titanium(IV) alkoxyl complexes have demonstrated significantly enhanced aqueous stability, their in vitro and in vivo antitumor efficacy, mechanism of action, structure-activity relationships and combined tumor therapy have been intensively investigated. Replacement of the labile alkoxyls with a second chelator resulted in structural rigid titanium(IV) complexes, which showed exceedingly good aqueous stability and potent antitumor activity both in vitro and in vivo. The unique ligand system successfully allowed the access of isotopic [45Ti]Titanium(IV) complexes, post-synthetic modification, facile synthetic protocols and antitumor congeneric zirconium(IV) and hafnium(IV) complexes. This review presents recent research progress in the field of antitumor group 4 metal complexes stabilized with phenolato ligands; especially their structure-activity relationships are summarized.
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Affiliation(s)
- Tiankun Zhao
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Peng Wang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Xupeng Zhang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Nan Liu
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Wenzhuo Zhao
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Yong Zhang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Pengpeng Yuan
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Shanjia Li
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Mingjun Yang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Zhongduo Yang
- College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, P.R. China
| | - Thomas Huhn
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr, 10, D-78457, Konstanz, Germany
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Abstract
Regioselective arrangement of two groups of orthogonal reactivity in bowl-shaped as-indaceno[3,2,1,8,7,6-pqrstuv]picene (Idpc) was key for the synthesis of hetero-bis-functionalized Idpc derivatives. Halogen and methyl groups were positioned at specific positions in the rim area of Idpc at an early stage during the synthesis by functionalization of suitable precursors. Regioselective functionalization of the bowl's rim was then finally achieved either via consecutive Cu(I)-catalyzed azide-alkyne coupling (CuAAC) and C-C cross-coupling reactions or by C-C cross-coupling alone, giving access to either symmetric or non-symmetric bis-functionalized Idpc derivatives. The self-aggregation behavior of 9c in solution was investigated by recording a series of concentration-dependent NMR spectra. The aggregation constant of 9c was determined by a nonlinear least-squares treatment of the 1H NMR shift data to be 2.9 ± 0.2 M-1, and the formation of dimers was found to be the prevailing process.
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Affiliation(s)
- Johannes Bayer
- Fachbereich Chemie, Universität Konstanz, D-78457 Konstanz, Germany
| | - Thomas Huhn
- Fachbereich Chemie, Universität Konstanz, D-78457 Konstanz, Germany
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Snegir S, Dappe YJ, Sysoiev D, Pluchery O, Huhn T, Scheer E. Where do the counterions go? Tip-induced dissociation of self-assembled triazatriangulenium-based molecules on Au(111). Phys Chem Chem Phys 2021; 23:9930-9937. [PMID: 33861285 DOI: 10.1039/d1cp00221j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chemical coupling of functional molecules on top of the so-called platform molecules allows the formation of functional self-assembled monolayers (SAMs). An often-used example of such a platform is triazatriangulenium (TATA), which features an extended aromatic core providing good electronic contact to the underlying metal surface. Here, we present a study of the SAM formation of a TATA platform on Au(111) employing scanning tunneling microscopy (STM) under ambient atmospheric conditions. In solution, the TATA platform is stabilized by BF4 counterions, while after deposition on a gold substrate, the localization of the BF4 counterions remains unknown. We used 1,2,4-trichlorobenzene as a solvent of TATA-BF4 to induce SAM formation on a heated (∼50 °C) Au substrate. We show by STM how to detect and distinguish TATA-BF4 from TATA platforms, which lost their BF4 counterions. Finally, we observe a change of the counterion position on the SAM during the STM scanning, which we explain by an electric-field-induced decrease of the electrostatic interaction in TATA-BF4 on the surface. We applied DFT calculations to reveal the influence of the gold lattice and the electric field of the STM tip on the stability of TATA-BF4 physisorbed on the surface.
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Affiliation(s)
- S Snegir
- Department of Physics, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany.
| | - Y J Dappe
- SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette Cedex, France
| | - D Sysoiev
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany
| | - O Pluchery
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris (INSP), 4 place Jussieu, 75005 Paris, France
| | - T Huhn
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany
| | - E Scheer
- Department of Physics, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany.
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7
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Bayer J, Herberger J, Holz L, Winter RF, Huhn T. Geodesic-Planar Conjugates: Substituted Buckybowls-Synthesis, Photoluminescence and Electrochemistry. Chemistry 2020; 26:17546-17558. [PMID: 32846003 PMCID: PMC7839787 DOI: 10.1002/chem.202003605] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/25/2020] [Indexed: 12/16/2022]
Abstract
C-C cross coupling products of bowl-shaped as-indaceno[3,2,1,8,7,6-pqrstuv]picene (Idpc) and different planar arenes and ethynyl-arenes were synthesized. Photoluminescence as well as electrochemical properties of all products were investigated and complemented by time-dependent quantum chemical calculations. UV/Vis spectroelectrochemistry investigations of the directly linked (Idpc)2 indicated the absence of any intramolecular charge-transfer transition of intermittently formed (Idpc)2 .- . All coupling products showed fluorescence. Ferrocene-1-yl-Idpc was structurally characterized by X-ray diffraction and is a rare example of a ferrocene-containing buckybowl exhibiting luminescence.
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Affiliation(s)
- Johannes Bayer
- Fachbereich ChemieUniversität KonstanzUniversitätsstr. 1078457KonstanzGermany
| | - Jan Herberger
- Fachbereich ChemieUniversität KonstanzUniversitätsstr. 1078457KonstanzGermany
| | - Lukas Holz
- Fachbereich ChemieUniversität KonstanzUniversitätsstr. 1078457KonstanzGermany
| | - Rainer F. Winter
- Fachbereich ChemieUniversität KonstanzUniversitätsstr. 1078457KonstanzGermany
| | - Thomas Huhn
- Fachbereich ChemieUniversität KonstanzUniversitätsstr. 1078457KonstanzGermany
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Xie X, Spiteller D, Huhn T, Schink B, Müller N. Desulfatiglans anilini Initiates Degradation of Aniline With the Production of Phenylphosphoamidate and 4-Aminobenzoate as Intermediates Through Synthases and Carboxylases From Different Gene Clusters. Front Microbiol 2020; 11:2064. [PMID: 33013754 PMCID: PMC7500099 DOI: 10.3389/fmicb.2020.02064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 08/05/2020] [Indexed: 01/22/2023] Open
Abstract
The anaerobic degradation of aniline was studied in the sulfate-reducing bacterium Desulfatiglans anilini. Our aim was to identify the genes and their proteins that are required for the initial activation of aniline as well as to characterize intermediates of this reaction. Aniline-induced genes were revealed by comparison of the proteomes of D. anilini grown with different substrates (aniline, 4-aminobenzoate, phenol, and benzoate). Most genes encoding proteins that were highly abundant in aniline- or 4-aminobenzoate-grown D. anilini cells but not in phenol- or benzoate-grown cells were located in the putative gene clusters ani (aniline degradation), hcr (4-hydroxybenzoyl-CoA reductase) and phe (phenol degradation). Of these putative gene clusters, only the phe gene cluster has been studied previously. Based on the differential proteome analysis, four candidate genes coding for kinase subunits and carboxylase subunits were suspected to be responsible for the initial conversion of aniline to 4-aminobenzoate. These genes were cloned and overproduced in E. coli. The recombinant proteins were obtained in inclusion bodies but could be refolded successfully. Two subunits of phenylphosphoamidate synthase and two carboxylase subunits converted aniline to 4-aminobenzoate with phenylphosphoamidate as intermediate under consumption of ATP. Only when both carboxylase subunits, one from gene cluster ani and the other from gene cluster phe, were combined, phenylphosphoamidate was converted to 4-aminobenzoate in vitro, with Mn2+, K+, and FMN as co-factors. Thus, aniline is degraded by the anaerobic bacterium D. anilini only by recruiting genes for the enzymatic machinery from different gene clusters. We conclude, that D. anilini carboxylates aniline to 4-aminobenzoate via phenylphosphoamidate as an energy rich intermediate analogous to the degradation of phenol to 4-hydroxybenzoate via phenylphosphate.
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Affiliation(s)
- Xiaoman Xie
- Department of Biology, Universität Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology, Konstanz, Germany
| | - Dieter Spiteller
- Department of Biology, Universität Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology, Konstanz, Germany
| | - Thomas Huhn
- Konstanz Research School Chemical Biology, Konstanz, Germany.,Department of Chemistry, Universität Konstanz, Konstanz, Germany
| | - Bernhard Schink
- Department of Biology, Universität Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology, Konstanz, Germany
| | - Nicolai Müller
- Department of Biology, Universität Konstanz, Konstanz, Germany
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Lenyk B, Schöps V, Boneberg J, Kabdulov M, Huhn T, Scheer E, Offenhäusser A, Mayer D. Surface Plasmon-Enhanced Switching Kinetics of Molecular Photochromic Films on Gold Nanohole Arrays. Nano Lett 2020; 20:5243-5250. [PMID: 32520573 DOI: 10.1021/acs.nanolett.0c01569] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Diarylethene molecules are discussed as possible optical switches, which can reversibly transition between completely conjugated (closed) and nonconjugated (open) forms with different electrical conductance and optical absorbance, by exposure to UV and visible light. However, in general the opening reaction exhibits much lower quantum yield than the closing process, hindering their usage in optoelectronic devices. To enhance the opening process, which is supported by visible light, we employ the plasmonic field enhancement of gold films perforated with nanoholes. We show that gold nanohole arrays reveal strong optical transmission in the visible range (∼60%) and pronounced enhancement of field intensities, resulting in around 50% faster switching kinetics of the molecular species in comparison with quartz substrates. The experimental UV-vis measurements are verified with finite-difference time-domain simulation that confirm the obtained results. Thus, we propose gold nanohole arrays as transparent and conductive plasmonic material that accelerates visible-light-triggered chemical reactions including molecular switching.
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Affiliation(s)
- Bohdan Lenyk
- Institute of Biological Information Processing (IBI-3), Forschungszentrum Jülich, 52428 Jülich, Germany
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
| | - Volker Schöps
- Institute of Biological Information Processing (IBI-3), Forschungszentrum Jülich, 52428 Jülich, Germany
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
| | - Johannes Boneberg
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
| | - Mikhail Kabdulov
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Thomas Huhn
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Elke Scheer
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
| | - Andreas Offenhäusser
- Institute of Biological Information Processing (IBI-3), Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Dirk Mayer
- Institute of Biological Information Processing (IBI-3), Forschungszentrum Jülich, 52428 Jülich, Germany
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Sysoiev D, Huhn T. Basic enemies of photochromism: irreversible transformation of fluorinated diarylethenes to polyenic enamines and enols. Photochem Photobiol Sci 2020; 19:1511-1516. [DOI: 10.1039/d0pp00292e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Elongating the π-system of perfluoro-diarylethenes under basic conditions inevitably leads to variable amounts of non-photochromic seven-ring containing byproducts.
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Affiliation(s)
- Dmytro Sysoiev
- Fachbereich Chemie
- Universität Konstanz
- 78464 Konstanz
- Germany
| | - Thomas Huhn
- Fachbereich Chemie
- Universität Konstanz
- 78464 Konstanz
- Germany
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Koo J, Jang Y, Martin L, Kim D, Jeong H, Kang K, Lee W, Kim J, Hwang WT, Xiang D, Scheer E, Kabdulov M, Huhn T, Pauly F, Lee T. Unidirectional Real-Time Photoswitching of Diarylethene Molecular Monolayer Junctions with Multilayer Graphene Electrodes. ACS Appl Mater Interfaces 2019; 11:11645-11653. [PMID: 30821955 DOI: 10.1021/acsami.8b19372] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We fabricate and characterize vertical molecular junctions consisting of self-assembled monolayers of diarylethene (DAE) contacted by a multilayer graphene (MLG) electrode on the top and gold on the bottom. The DAE molecular junctions show two stable electrical states, a closed state (high conductance) or an open state (low conductance), which are created upon illumination with UV or visible light, respectively. For the Au-DAE-MLG junction structure, we observe that the current levels between the two conductance states are separated by 2 orders of magnitude. However, in a real-time measurement, we observe only unidirectional switching behavior from the open to the closed state.
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Affiliation(s)
- Jeongmin Koo
- Department of Physics and Astronomy, and Institute of Applied Physics , Seoul National University , Seoul 08826 , Korea
| | - Yeonsik Jang
- Department of Physics and Astronomy, and Institute of Applied Physics , Seoul National University , Seoul 08826 , Korea
| | - León Martin
- Okinawa Institute of Science and Technology Graduate University , Onna-son, Okinawa 904-0495 , Japan
| | | | - Hyunhak Jeong
- Department of Physics and Astronomy, and Institute of Applied Physics , Seoul National University , Seoul 08826 , Korea
| | - Keehoon Kang
- Department of Physics and Astronomy, and Institute of Applied Physics , Seoul National University , Seoul 08826 , Korea
| | - Woocheol Lee
- Department of Physics and Astronomy, and Institute of Applied Physics , Seoul National University , Seoul 08826 , Korea
| | - Junwoo Kim
- Department of Physics and Astronomy, and Institute of Applied Physics , Seoul National University , Seoul 08826 , Korea
| | - Wang-Taek Hwang
- Department of Physics and Astronomy, and Institute of Applied Physics , Seoul National University , Seoul 08826 , Korea
| | - Dong Xiang
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, College of Electronic Information and Optical Engineering , Nankai University , 300071 Tianjin , China
| | | | | | | | - Fabian Pauly
- Okinawa Institute of Science and Technology Graduate University , Onna-son, Okinawa 904-0495 , Japan
| | - Takhee Lee
- Department of Physics and Astronomy, and Institute of Applied Physics , Seoul National University , Seoul 08826 , Korea
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Burrichter A, Denger K, Franchini P, Huhn T, Müller N, Spiteller D, Schleheck D. Anaerobic Degradation of the Plant Sugar Sulfoquinovose Concomitant With H 2S Production: Escherichia coli K-12 and Desulfovibrio sp. Strain DF1 as Co-culture Model. Front Microbiol 2018; 9:2792. [PMID: 30546350 PMCID: PMC6278857 DOI: 10.3389/fmicb.2018.02792] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 10/30/2018] [Indexed: 11/13/2022] Open
Abstract
Sulfoquinovose (SQ, 6-deoxy-6-sulfoglucose) is produced by plants and other phototrophs and its biodegradation is a relevant component of the biogeochemical carbon and sulfur cycles. SQ is known to be degraded by aerobic bacterial consortia in two tiers via C3-organosulfonates as transient intermediates to CO2, water and sulfate. In this study, we present a first laboratory model for anaerobic degradation of SQ by bacterial consortia in two tiers to acetate and hydrogen sulfide (H2S). For the first tier, SQ-degrading Escherichia coli K-12 was used. It catalyzes the fermentation of SQ to 2,3-dihydroxypropane-1-sulfonate (DHPS), succinate, acetate and formate, thus, a novel type of mixed-acid fermentation. It employs the characterized SQ Embden-Meyerhof-Parnas pathway, as confirmed by mutational and proteomic analyses. For the second tier, a DHPS-degrading Desulfovibrio sp. isolate from anaerobic sewage sludge was used, strain DF1. It catalyzes another novel fermentation, of the DHPS to acetate and H2S. Its DHPS desulfonation pathway was identified by differential proteomics and demonstrated by heterologously produced enzymes: DHPS is oxidized via 3-sulfolactaldehyde to 3-sulfolactate (SL) by two NAD+-dependent dehydrogenases (DhpA, SlaB); the SL is cleaved by an SL sulfite-lyase known from aerobic bacteria (SuyAB) to pyruvate and sulfite. The pyruvate is oxidized to acetate, while the sulfite is used as electron acceptor in respiration and reduced to H2S. In conclusion, anaerobic sulfidogenic SQ degradation was demonstrated as a novel link in the biogeochemical sulfur cycle. SQ is also a constituent of the green-vegetable diet of herbivores and omnivores and H2S production in the intestinal microbiome has many recognized and potential contributions to human health and disease. Hence, it is important to examine bacterial SQ degradation also in the human intestinal microbiome, in relation to H2S production, dietary conditions and human health.
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Affiliation(s)
- Anna Burrichter
- Department of Biology, University of Konstanz, Konstanz, Germany.,The Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Karin Denger
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Paolo Franchini
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Thomas Huhn
- The Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany.,Department of Chemistry, University of Konstanz, Konstanz, Germany
| | - Nicolai Müller
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Dieter Spiteller
- Department of Biology, University of Konstanz, Konstanz, Germany.,The Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
| | - David Schleheck
- Department of Biology, University of Konstanz, Konstanz, Germany.,The Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
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13
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Siemes E, Nevskyi O, Sysoiev D, Turnhoff SK, Oppermann A, Huhn T, Richtering W, Wöll D. Nanoscopic Visualization of Cross-Linking Density in Polymer Networks with Diarylethene Photoswitches. Angew Chem Int Ed Engl 2018; 57:12280-12284. [DOI: 10.1002/anie.201807741] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 07/27/2018] [Indexed: 12/22/2022]
Affiliation(s)
- Eric Siemes
- Institute for Physical Chemistry; RWTH Aachen University; Landoltweg 2 52074 Aachen Germany
| | - Oleksii Nevskyi
- Institute for Physical Chemistry; RWTH Aachen University; Landoltweg 2 52074 Aachen Germany
| | - Dmytro Sysoiev
- Department of Chemistry; University of Konstanz; Universitätsstrasse 10 78464 Konstanz Germany
| | - Sarah K. Turnhoff
- Institute for Physical Chemistry; RWTH Aachen University; Landoltweg 2 52074 Aachen Germany
| | - Alex Oppermann
- Institute for Physical Chemistry; RWTH Aachen University; Landoltweg 2 52074 Aachen Germany
| | - Thomas Huhn
- Department of Chemistry; University of Konstanz; Universitätsstrasse 10 78464 Konstanz Germany
| | - Walter Richtering
- Institute for Physical Chemistry; RWTH Aachen University; Landoltweg 2 52074 Aachen Germany
| | - Dominik Wöll
- Institute for Physical Chemistry; RWTH Aachen University; Landoltweg 2 52074 Aachen Germany
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14
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Siemes E, Nevskyi O, Sysoiev D, Turnhoff SK, Oppermann A, Huhn T, Richtering W, Wöll D. Nanoskopische Bildgebung der Vernetzungsdichte in Polymernetzwerken mittels Diarylethen-Photoschaltern. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201807741] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Eric Siemes
- Institut für Physikalische Chemie; RWTH Aachen; Landoltweg 2 52074 Aachen Deutschland
| | - Oleksii Nevskyi
- Institut für Physikalische Chemie; RWTH Aachen; Landoltweg 2 52074 Aachen Deutschland
| | - Dmytro Sysoiev
- Fachbereich Chemie; Universität Konstanz; Universitätsstraße 10 78464 Konstanz Deutschland
| | - Sarah K. Turnhoff
- Institut für Physikalische Chemie; RWTH Aachen; Landoltweg 2 52074 Aachen Deutschland
| | - Alex Oppermann
- Institut für Physikalische Chemie; RWTH Aachen; Landoltweg 2 52074 Aachen Deutschland
| | - Thomas Huhn
- Fachbereich Chemie; Universität Konstanz; Universitätsstraße 10 78464 Konstanz Deutschland
| | - Walter Richtering
- Institut für Physikalische Chemie; RWTH Aachen; Landoltweg 2 52074 Aachen Deutschland
| | - Dominik Wöll
- Institut für Physikalische Chemie; RWTH Aachen; Landoltweg 2 52074 Aachen Deutschland
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15
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Nevskyi O, Sysoiev D, Dreier J, Stein SC, Oppermann A, Lemken F, Janke T, Enderlein J, Testa I, Huhn T, Wöll D. Fluorescent Diarylethene Photoswitches-A Universal Tool for Super-Resolution Microscopy in Nanostructured Materials. Small 2018; 14:1703333. [PMID: 29325203 DOI: 10.1002/smll.201703333] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/03/2017] [Indexed: 06/07/2023]
Abstract
Super-resolution fluorescence microscopy allows for unprecedented in situ visualization of biological structures, but its application to materials science has so far been comparatively limited. One of the main reasons is the lack of powerful dyes that allow for labeling and photoswitching in materials science systems. In this study it is shown that appropriate substitution of diarylethenes bearing a fluorescent closed and dark open form paves the way for imaging nanostructured materials with three of the most popular super-resolution fluorescence microscopy methods that are based on different concepts to achieve imaging beyond the diffraction limit of light. The key to obtain optimal resolution lies in a proper control over the photochemistry of the photoswitches and its adaption to the system to be imaged. It is hoped that the present work will provide researchers with a guide to choose the best photoswitch derivative for super-resolution microscopy in materials science, just like the correct choice of a Swiss Army Knife's tool is essential to fulfill a given task.
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Affiliation(s)
- Oleksii Nevskyi
- Institute for Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074, Aachen, Germany
| | - Dmytro Sysoiev
- Department of Chemistry, University of Konstanz, Universitätsstr. 10, 78464, Konstanz, Germany
| | - Jes Dreier
- Science for Life Laboratory, KTH Royal Institute of Technology, Tomtebodavägen 23A, 17121, Solna, Sweden
| | - Simon Christoph Stein
- III. Institute of Physics - Biophysics, Georg-August University, Friedrich-Hund-Platz 1, 37077, Göttingen, Germany
| | - Alex Oppermann
- Institute for Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074, Aachen, Germany
| | - Florian Lemken
- Institute for Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074, Aachen, Germany
| | - Tobias Janke
- Institute for Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074, Aachen, Germany
| | - Jörg Enderlein
- III. Institute of Physics - Biophysics, Georg-August University, Friedrich-Hund-Platz 1, 37077, Göttingen, Germany
| | - Ilaria Testa
- Science for Life Laboratory, KTH Royal Institute of Technology, Tomtebodavägen 23A, 17121, Solna, Sweden
| | - Thomas Huhn
- Department of Chemistry, University of Konstanz, Universitätsstr. 10, 78464, Konstanz, Germany
| | - Dominik Wöll
- Institute for Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074, Aachen, Germany
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16
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Schneider F, Zhao T, Huhn T. Cytotoxic heteroleptic heptacoordinate salan zirconium(iv)-bis-chelates - synthesis, aqueous stability and X-ray structure analysis. Chem Commun (Camb) 2018; 52:10151-4. [PMID: 27459052 DOI: 10.1039/c6cc05359a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein we report the synthesis and structural characterization of a series of novel Zr(iv)salan complexes. The initial metalation product [(L1)2Zr] is highly water sensitive while ligand exchanged [L1Zr(dipic)] hydrolyses slowly with a bis-hydroxo Zr(iv) species identified by MS as an intermediate. [L1Zr(dipic)] is cytotoxic in the range of cisplatin against two human carcinoma cell lines.
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Affiliation(s)
- Fabian Schneider
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany.
| | - Tiankun Zhao
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany.
| | - Thomas Huhn
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany.
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17
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Schöps V, Lenyk B, Huhn T, Boneberg J, Scheer E, Offenhäusser A, Mayer D. Facile, non-destructive characterization of 2d photonic crystals using UV-vis-spectroscopy. Phys Chem Chem Phys 2018; 20:4340-4346. [DOI: 10.1039/c7cp07498k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The quality of particle monolayers and size evolution of their particles during dry etching can be monitored by radiative losses of photonic modes into dielectric substrates.
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Affiliation(s)
- V. Schöps
- Department of Physics
- University of Konstanz
- 78457 Konstanz
- Germany
- Institute of Complex Systems (ICS-8)
| | - B. Lenyk
- Department of Physics
- University of Konstanz
- 78457 Konstanz
- Germany
- Institute of Complex Systems (ICS-8)
| | - T. Huhn
- Department of Chemistry
- University of Konstanz
- 78457 Konstanz
- Germany
| | - J. Boneberg
- Department of Physics
- University of Konstanz
- 78457 Konstanz
- Germany
| | - E. Scheer
- Department of Physics
- University of Konstanz
- 78457 Konstanz
- Germany
| | - A. Offenhäusser
- Institute of Complex Systems (ICS-8)
- Bioelectronics
- Forschungszentrum Jülich
- 52428 Jülich
- Germany
| | - D. Mayer
- Institute of Complex Systems (ICS-8)
- Bioelectronics
- Forschungszentrum Jülich
- 52428 Jülich
- Germany
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18
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Kim Y, Bahoosh SG, Sysoiev D, Huhn T, Pauly F, Scheer E. Inelastic electron tunneling spectroscopy of difurylethene-based photochromic single-molecule junctions. Beilstein J Nanotechnol 2017; 8:2606-2614. [PMID: 29259875 PMCID: PMC5727803 DOI: 10.3762/bjnano.8.261] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 11/17/2017] [Indexed: 06/07/2023]
Abstract
Diarylethene-derived molecules alter their electronic structure upon transformation between the open and closed forms of the diarylethene core, when exposed to ultraviolet (UV) or visible light. This transformation results in a significant variation of electrical conductance and vibrational properties of corresponding molecular junctions. We report here a combined experimental and theoretical analysis of charge transport through diarylethene-derived single-molecule devices, which are created using the mechanically controlled break-junction technique. Inelastic electron tunneling (IET) spectroscopy measurements performed at 4.2 K are compared with first-principles calculations in the two distinct forms of diarylethenes connected to gold electrodes. The combined approach clearly demonstrates that the IET spectra of single-molecule junctions show specific vibrational features that can be used to identify different isomeric molecular states by transport experiments.
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Affiliation(s)
- Youngsang Kim
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Lam Research, Fremont, California 94538, United States
| | - Safa G Bahoosh
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
| | - Dmytro Sysoiev
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Thomas Huhn
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Fabian Pauly
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
- Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa 904-0395, Japan
| | - Elke Scheer
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
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19
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Reecht G, Lotze C, Sysoiev D, Huhn T, Franke KJ. Disentangling electron- and electric-field-induced ring-closing reactions in a diarylethene derivative on Ag(1 1 1). J Phys Condens Matter 2017; 29:294001. [PMID: 28557794 DOI: 10.1088/1361-648x/aa75c1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Using scanning tunneling microscopy and spectroscopy we investigate the adsorption properties and ring-closing reaction of a diarylethene derivative (C5F-4Py) on a Ag(1 1 1) surface. We identify an electron-induced reaction mechanism, with a quantum yield varying from 10-14-10-9 per electron upon variation of the bias voltage from 1-2 V. We ascribe the drastic increase in switching efficiency to a resonant enhancement upon tunneling through molecular orbitals. Additionally, we resolve the ring-closing reaction even in the absence of a current passing through the molecule. In this case the electric-field can modify the reaction barrier, leading to a finite switching probability at 4.8 K. A detailed analysis of the switching events shows that a simple plate-capacitor model for the tip-surface junction is insufficient to explain the distance dependence of the switching voltage. Instead, describing the tip as a sphere is in agreement with the findings. We resolve small differences in the adsorption configuration of the closed isomer, when comparing the electron- and field-induced switching product.
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Affiliation(s)
- Gaël Reecht
- Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
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20
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Snegir S, Khodko A, Sysoiev D, Lacaze E, Pluchery O, Huhn T. Optical properties of gold nanoparticles decorated with furan-based diarylethene photochromic molecules. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2017.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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21
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El-Guebaly L, Huhn T, Rowcliffe A, Malang S. Design Challenges and Activation Concerns for ARIES Vacuum Vessel. Fusion Science and Technology 2017. [DOI: 10.13182/fst64-449] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- L. El-Guebaly
- University of Wisconsin, 1500 Engineering Dr., Madison, WI 53706, USA
| | - T. Huhn
- University of Wisconsin, 1500 Engineering Dr., Madison, WI 53706, USA
| | | | - S. Malang
- Fusion Nuclear Technology Consulting, Germany
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22
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Khodko A, Khomenko V, Shynkarenko Y, Mamuta O, Kapitanchuk O, Sysoiev D, Kachalova N, Huhn T, Snegir S. Ultrafast ring-closing reaction dynamics of a photochromic furan-based difurylethene. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2016.12.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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23
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Reecht G, Lotze C, Sysoiev D, Huhn T, Franke K. Visualizing the Role of Molecular Orbitals in Charge Transport through Individual Diarylethene Isomers. ACS Nano 2016; 10:10555-10562. [PMID: 27775886 PMCID: PMC5135228 DOI: 10.1021/acsnano.6b06559] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023]
Abstract
Diarylethene molecules are prototype molecular switches with their two isomeric forms exhibiting strikingly different conductance, while maintaining similar length. We employed low-temperature scanning tunneling microscopy (STM) to resolve the energy and the spatial extend of the molecular orbitals of the open and closed isomers when lying on a Au(111) surface. We find an intriguing difference in the extension of the respective HOMOs and a peculiar energy splitting of the formerly degenerate LUMO of the open isomer. We then lift the two isomers with the tip of the STM and measure the current through the individual molecules. By a simple analytical model of the transport, we show that the previously determined orbital characteristics are essential ingredients for the complete understanding of the transport properties. We also succeeded in switching the suspended molecules by the current, while switching the ones which are in direct contact to the surface occurs nonlocally with the help of the electric field of the tip.
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Affiliation(s)
- Gaël Reecht
- Institut
für Experimentalphysik, Freie Universität
Berlin, Arnimallee 14, Berlin 14195, Germany
| | - Christian Lotze
- Institut
für Experimentalphysik, Freie Universität
Berlin, Arnimallee 14, Berlin 14195, Germany
| | - Dmytro Sysoiev
- Fachbereich
Chemie, Universität Konstanz, Universitätsstraße 10, Konstanz 78457, Germany
| | - Thomas Huhn
- Fachbereich
Chemie, Universität Konstanz, Universitätsstraße 10, Konstanz 78457, Germany
| | - Katharina
J. Franke
- Institut
für Experimentalphysik, Freie Universität
Berlin, Arnimallee 14, Berlin 14195, Germany
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24
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Nevskyi O, Sysoiev D, Oppermann A, Huhn T, Wöll D. Nanoscopic Visualization of Soft Matter Using Fluorescent Diarylethene Photoswitches. Angew Chem Int Ed Engl 2016; 55:12698-702. [PMID: 27619176 DOI: 10.1002/anie.201606791] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Indexed: 11/07/2022]
Abstract
The in situ imaging of soft matter is of paramount importance for a detailed understanding of functionality on the nanoscopic scale. Although super-resolution fluorescence microscopy methods with their unprecedented imaging capabilities have revolutionized research in the life sciences, this potential has been far less exploited in materials science. One of the main obstacles for a more universal application of super-resolved fluorescence microscopy methods is the limitation of readily available suitable dyes to overcome the diffraction limit. Here, we report a novel diarylethene-based photoswitch with a highly fluorescent closed and a nonfluorescent open form. Its photophysical properties, switching behavior, and high photostability make the dye an ideal candidate for photoactivation localization microscopy (PALM). It is capable of resolving apolar structures with an accuracy far beyond the diffraction limit of optical light in cylindrical micelles formed by amphiphilic block copolymers.
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Affiliation(s)
- Oleksii Nevskyi
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074, Aachen, Germany
| | - Dmytro Sysoiev
- Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78464, Konstanz, Germany
| | - Alex Oppermann
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074, Aachen, Germany
| | - Thomas Huhn
- Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78464, Konstanz, Germany
| | - Dominik Wöll
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074, Aachen, Germany.
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25
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Nevskyi O, Sysoiev D, Oppermann A, Huhn T, Wöll D. Nanoskopische Bildgebung weicher Materie mittels fluoreszierender Diarylethen-Photoschalter. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201606791] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Oleksii Nevskyi
- Institut für Physikalische Chemie; RWTH Aachen University; Landoltweg 2 52074 Aachen Deutschland
| | - Dmytro Sysoiev
- Fachbereich Chemie; Universität Konstanz; Universitätsstraße 10 78464 Konstanz Deutschland
| | - Alex Oppermann
- Institut für Physikalische Chemie; RWTH Aachen University; Landoltweg 2 52074 Aachen Deutschland
| | - Thomas Huhn
- Fachbereich Chemie; Universität Konstanz; Universitätsstraße 10 78464 Konstanz Deutschland
| | - Dominik Wöll
- Institut für Physikalische Chemie; RWTH Aachen University; Landoltweg 2 52074 Aachen Deutschland
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26
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Hayakawa R, Karimi MA, Wolf J, Huhn T, Zöllner MS, Herrmann C, Scheer E. Large Magnetoresistance in Single-Radical Molecular Junctions. Nano Lett 2016; 16:4960-4967. [PMID: 27458666 DOI: 10.1021/acs.nanolett.6b01595] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Organic radicals are promising building blocks for molecular spintronics. Little is known about the role of unpaired electrons for electron transport at the single-molecule level. Here, we examine the impact of magnetic fields on electron transport in single oligo(p-phenyleneethynylene) (OPE)-based radical molecular junctions, which are formed with a mechanically controllable break-junction technique at a low temperature of 4.2 K. Surprisingly huge positive magnetoresistances (MRs) of 16 to 287% are visible for a magnetic field of 4 T, and the values are at least 1 order of magnitude larger than those of the analogous pristine OPE (2-4%). Rigorous analysis of the MR and of current-voltage and inelastic electron-tunneling spectroscopy measurements reveal an effective reduction of the electronic coupling between the current-carrying molecular orbital and the electrodes with increasing magnetic field. We suggest that the large MR for the single-radical molecular junctions might be ascribed to a loss of phase coherence of the charge carriers induced by the magnetic field. Although further investigations are required to reveal the mechanism underlying the strong MR, our findings provide a potential approach for tuning charge transport in metal-molecule junctions with organic radicals.
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Affiliation(s)
- Ryoma Hayakawa
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science , 1-1 Namiki, Tsukuba 305-0044, Japan
| | | | | | | | - Martin Sebastian Zöllner
- Institute for Inorganic and Applied Chemistry, University of Hamburg , Martin-Luther-King-Platz 6, 20146 Hamburg, Germany
| | - Carmen Herrmann
- Institute for Inorganic and Applied Chemistry, University of Hamburg , Martin-Luther-King-Platz 6, 20146 Hamburg, Germany
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27
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Luka-Guth K, Hambsch S, Bloch A, Ehrenreich P, Briechle BM, Kilibarda F, Sendler T, Sysoiev D, Huhn T, Erbe A, Scheer E. Role of solvents in the electronic transport properties of single-molecule junctions. Beilstein J Nanotechnol 2016; 7:1055-67. [PMID: 27547624 PMCID: PMC4979908 DOI: 10.3762/bjnano.7.99] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 06/07/2016] [Indexed: 06/06/2023]
Abstract
We report on an experimental study of the charge transport through tunnel gaps formed by adjustable gold electrodes immersed into different solvents that are commonly used in the field of molecular electronics (ethanol, toluene, mesitylene, 1,2,4-trichlorobenzene, isopropanol, toluene/tetrahydrofuran mixtures) for the study of single-molecule contacts of functional molecules. We present measurements of the conductance as a function of gap width, conductance histograms as well as current-voltage characteristics of narrow gaps and discuss them in terms of the Simmons model, which is the standard model for describing transport via tunnel barriers, and the resonant single-level model, often applied to single-molecule junctions. One of our conclusions is that stable junctions may form from solvents as well and that both conductance-distance traces and current-voltage characteristics have to be studied to distinguish between contacts of solvent molecules and of molecules under study.
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Affiliation(s)
| | - Sebastian Hambsch
- Physics Department, University of Konstanz, D-78457 Konstanz, Germany
| | - Andreas Bloch
- Physics Department, University of Konstanz, D-78457 Konstanz, Germany
| | | | | | - Filip Kilibarda
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, D-01328 Dresden, Germany
| | - Torsten Sendler
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, D-01328 Dresden, Germany
| | - Dmytro Sysoiev
- Chemistry Department, University of Konstanz, D-78457 Konstanz, Germany
| | - Thomas Huhn
- Chemistry Department, University of Konstanz, D-78457 Konstanz, Germany
| | - Artur Erbe
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, D-01328 Dresden, Germany
| | - Elke Scheer
- Physics Department, University of Konstanz, D-78457 Konstanz, Germany
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Pesch T, Schuhwerk H, Wyrsch P, Immel T, Dirks W, Bürkle A, Huhn T, Beneke S. Differential cytotoxicity induced by the Titanium(IV)Salan complex Tc52 in G2-phase independent of DNA damage. BMC Cancer 2016; 16:469. [PMID: 27412346 PMCID: PMC4944496 DOI: 10.1186/s12885-016-2538-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 07/08/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Chemotherapy is one of the major treatment modalities for cancer. Metal-based compounds such as derivatives of cisplatin are in the front line of therapy against a subset of cancers, but their use is restricted by severe side-effects and the induction of resistance in treated tumors. Subsequent research focused on development of cytotoxic metal-complexes without cross-resistance to cisplatin and reduced side-effects. This led to the discovery of first-generation titanium(IV)salan complexes, which reached clinical trials but lacked efficacy. New-generation titanium (IV)salan-complexes show promising anti-tumor activity in mice, but their molecular mechanism of cytotoxicity is completely unknown. METHODS Four different human cell lines were analyzed in their responses to a toxic (Tc52) and a structurally highly related but non-toxic (Tc53) titanium(IV)salan complex. Viability assays were used to reveal a suitable treatment range, flow-cytometry analysis was performed to monitor the impact of dosage and treatment time on cell-cycle distribution and cell death. Potential DNA strand break induction and crosslinking was investigated by immunostaining of damage markers as well as automated fluorometric analysis of DNA unwinding. Changes in nuclear morphology were analyzed by DAPI staining. Acidic beta-galactosidase activity together with morphological changes was monitored to detect cellular senescence. Western blotting was used to analyze induction of pro-apoptotic markers such as activated caspase7 and cleavage of PARP1, and general stress kinase p38. RESULTS Here we show that the titanium(IV)salan Tc52 is effective in inducing cell death in the lower micromolar range. Surprisingly, Tc52 does not target DNA contrary to expectations deduced from the reported activity of other titanium complexes. Instead, Tc52 application interferes with progression from G2-phase into mitosis and induces apoptotic cell death in tested tumor cells. Contrarily, human fibroblasts undergo senescence in a time and dose-dependent manner. As deduced from fluorescence studies, the potential cellular target seems to be the cytoskeleton. CONCLUSIONS In summary, we could demonstrate in four different human cell lines that tumor cells were specifically killed without induction of major cytotoxicity in non-tumorigenic cells. Absence of DNA damaging activity and the cell-cycle block in G2 instead of mitosis makes Tc52 an attractive compound for further investigations in cancer treatment.
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Affiliation(s)
- Theresa Pesch
- University of Zurich, Institute of Veterinary Pharmacology and Toxicology, 8057, Zurich, Switzerland
| | - Harald Schuhwerk
- University of Konstanz, Molecular Toxicology Group, 78457, Konstanz, Germany.,Present address: Leibniz Institute for Age Research: FLI, Beutenbergstr. 11, 07745, Jena, Germany
| | - Philippe Wyrsch
- University of Zurich, Institute of Veterinary Pharmacology and Toxicology, 8057, Zurich, Switzerland
| | - Timo Immel
- Department of Chemistry, University of Konstanz, 78457, Konstanz, Germany.,Present address: Lanxess, 41539, Dormagen, Germany
| | - Wilhelm Dirks
- Leibniz Institute DSMZ, Molecular Biology Group, 38124, Braunschweig, Germany
| | - Alexander Bürkle
- University of Konstanz, Molecular Toxicology Group, 78457, Konstanz, Germany
| | - Thomas Huhn
- Department of Chemistry, University of Konstanz, 78457, Konstanz, Germany
| | - Sascha Beneke
- University of Zurich, Institute of Veterinary Pharmacology and Toxicology, 8057, Zurich, Switzerland. .,Present address: Department of Biology, University of Konstanz, Ecotoxicology Group, 78457, Konstanz, Germany.
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Zhao T, Grützke M, Götz KH, Druzhenko T, Huhn T. Synthesis and X-ray structure analysis of cytotoxic heptacoordinate sulfonamide salan titanium(IV)-bis-chelates. Dalton Trans 2016; 44:16475-85. [PMID: 26325575 DOI: 10.1039/c5dt01618e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of novel sulfonamide substituted heteroleptic salan titanium(IV)-bis-chelates complexed to 2,6-pyridinedicarboxylic acid were synthesized, structurally characterized and evaluated for their anticancer activity against two human carcinoma cell lines. All cytotoxic complexes showed complete inhibition of cell growth at active concentration, two complexes based on pyrrolidine and azepane substituted sulfonamides displayed IC50 values below 1.7 μM and are more cytotoxic than cisplatin in both tested cell lines. The azepane substituted complex [L3Ti(dipic)] exhibited excellent activity with an IC50 value of 0.5 ± 0.1 μM in Hela S3 and 1.0 ± 0.1 μM in Hep G2.
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Affiliation(s)
- Tiankun Zhao
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany.
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Verdonck R, De Haes W, Cardoen D, Menschaert G, Huhn T, Landuyt B, Baggerman G, Boonen K, Wenseleers T, Schoofs L. Fast and Reliable Quantitative Peptidomics with labelpepmatch. J Proteome Res 2016; 15:1080-9. [DOI: 10.1021/acs.jproteome.5b00845] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | - Gerben Menschaert
- Research
Group of Bio-informatics and Computational Genomics, Ghent University, Ghent, Belgium
| | - Thomas Huhn
- Chemistry
Department, University of Konstanz, Konstanz, Germany
| | | | - Geert Baggerman
- CFP/CeProMa, Antwerp University, Antwerp, Belgium
- Applied Bio & Molecular Systems, Vito, Mol, Belgium
| | - Kurt Boonen
- Biology
Department, KU Leuven, Leuven, Belgium
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Kastl J, Braun J, Prestel A, Möller HM, Huhn T, Mayer TU. Mad2 Inhibitor-1 (M2I-1): A Small Molecule Protein-Protein Interaction Inhibitor Targeting the Mitotic Spindle Assembly Checkpoint. ACS Chem Biol 2015; 10:1661-6. [PMID: 25978000 DOI: 10.1021/acschembio.5b00121] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The genetic integrity of each organism depends on the faithful segregation of its genome during mitosis. To meet this challenge, a cellular surveillance mechanism, termed the spindle assembly checkpoint (SAC), evolved that monitors the correct attachment of chromosomes and blocks progression through mitosis if corrections are needed. While the central role of the SAC for genome integrity is well established, its functional dissection has been hampered by the limited availability of appropriate small molecule inhibitors. Using a fluorescence polarization-based screen, we identify Mad2 inhibitor-1 (M2I-1), the first small molecule inhibitor targeting the binding of Mad2 to Cdc20, an essential protein-protein interaction (PPI) within the SAC. Based on computational and biochemical analyses, we propose that M2I-1 disturbs conformational dynamics of Mad2 critical for complex formation with Cdc20. Cellular studies revealed that M2I-1 weakens the SAC response, indicating that the compound might be active in cells. Thus, our study identifies the SAC specific complex formation between Mad2 and Cdc20 as a protein-protein interaction that can be targeted by small molecules.
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Affiliation(s)
- Johanna Kastl
- Department
of Biology and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstr. 10, 78462 Konstanz, Germany
| | - Joachim Braun
- Department
of Chemistry and Konstanz Research School Chemical-Biology (KoRS-CB), University of Konstanz, Universitätsstr. 10, 78462 Konstanz, Germany
| | - Andreas Prestel
- Department
of Chemistry and Konstanz Research School Chemical-Biology (KoRS-CB), University of Konstanz, Universitätsstr. 10, 78462 Konstanz, Germany
| | - Heiko M. Möller
- Department
of Chemistry and Konstanz Research School Chemical-Biology (KoRS-CB), University of Konstanz, Universitätsstr. 10, 78462 Konstanz, Germany
- Institute
of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany
| | - Thomas Huhn
- Department
of Chemistry and Konstanz Research School Chemical-Biology (KoRS-CB), University of Konstanz, Universitätsstr. 10, 78462 Konstanz, Germany
| | - Thomas U. Mayer
- Department
of Biology and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstr. 10, 78462 Konstanz, Germany
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Erler P, Schmitt P, Barth N, Irmler A, Bouvron S, Huhn T, Groth U, Pauly F, Gragnaniello L, Fonin M. Highly Ordered Surface Self-Assembly of Fe₄ Single Molecule Magnets. Nano Lett 2015; 15:4546-52. [PMID: 26086677 DOI: 10.1021/acs.nanolett.5b01120] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Single molecule magnets (SMMs) have attracted considerable attention due to low-temperature magnetic hysteresis and fascinating quantum effects. The investigation of these properties requires the possibility to deposit well-defined monolayers or spatially isolated molecules within a well-controlled adsorption geometry. Here we present a successful fabrication of self-organized arrays of Fe4 SMMs on hexagonal boron nitride (h-BN) on Rh(111) as template. Using a rational design of the ligand shell optimized for surface assembly and electrospray as a gentle deposition method, we demonstrate how to obtain ordered arrays of molecules forming perfect hexagonal superlattices of tunable size, from small islands to an almost perfect monolayer. High-resolution low temperature scanning tunneling microscopy (STM) reveals that the Fe4 molecule adsorbs on the substrate in a flat geometry, meaning that its magnetic easy axis is perpendicular to the surface. By scanning tunneling spectroscopy (STS) and density functional theory (DFT) calculations, we infer that the majority- and minority-spin components of the spin-split lowest unoccupied molecular orbital (LUMO) can be addressed separately on a submolecular level.
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Affiliation(s)
- Philipp Erler
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | | | - Nicole Barth
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Andreas Irmler
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Samuel Bouvron
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | | | | | - Fabian Pauly
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Luca Gragnaniello
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Mikhail Fonin
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
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Grützke M, Zhao T, Immel TA, Huhn T. Heptacoordinate Heteroleptic Salan (ONNO) and Thiosalan (OSSO) Titanium(IV) Complexes: Investigation of Stability and Cytotoxicity. Inorg Chem 2015; 54:6697-706. [PMID: 26151574 DOI: 10.1021/acs.inorgchem.5b00690] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Seven heptacoordinate titanium(IV) complexes were synthesized based on the concept of hetero-bis-chelate stabilization of salan (ONNO) and thiosalan (OSSO) titanium(IV)alkoxides with 2,6-pyridinedicarboxylic acid (dipic) and derivatives thereof. The resulting compounds were investigated in a solid by X-ray diffraction and in solution by NMR spectroscopy. A thiosalan (OSSO) titanium(IV) complex could be isolated and its conformational stabilization by dipic was shown by (1)H NMR spectroscopy to lead to nonfluxional behavior even at room temperature. The stability of selected complexes was assessed at pH 1.9, 6.8, and 12.1 by an UV-vis monitored hydrolysis study with >5 Mio. equivalents of water. Even at pH 12.1 [L(1)Ti(dipic)(1)] showed t1/2 of more than 2 days. The cytotoxicity of all compounds was investigated in two human carcinoma cell lines. IC50-values in the range of cisplatin were achieved by all tested compounds except for [L(4)Ti(dipic)(1)], which was proven to be nontoxic. The functionalization of dipic was thus well tolerated and did neither interfere with the stability nor the cytotoxicity of the heteroleptic complexes.
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Affiliation(s)
- Martin Grützke
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany
| | - Tiankun Zhao
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany
| | - Timo A Immel
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany
| | - Thomas Huhn
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstr. 10, D-78457 Konstanz, Germany
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Sendler T, Luka-Guth K, Wieser M, Lokamani, Wolf J, Helm M, Gemming S, Kerbusch J, Scheer E, Huhn T, Erbe A. Light-Induced Switching of Tunable Single-Molecule Junctions. Adv Sci (Weinh) 2015; 2:1500017. [PMID: 27980936 PMCID: PMC5115361 DOI: 10.1002/advs.201500017] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/13/2015] [Indexed: 12/12/2023]
Abstract
A major goal of molecular electronics is the development and implementation of devices such as single-molecular switches. Here, measurements are presented that show the controlled in situ switching of diarylethene molecules from their nonconductive to conductive state in contact to gold nanoelectrodes via controlled light irradiation. Both the conductance and the quantum yield for switching of these molecules are within a range making the molecules suitable for actual devices. The conductance of the molecular junctions in the opened and closed states is characterized and the molecular level E0, which dominates the current transport in the closed state, and its level broadening Γ are identified. The obtained results show a clear light-induced ring forming isomerization of the single-molecule junctions. Electron withdrawing side-groups lead to a reduction of conductance, but do not influence the efficiency of the switching mechanism. Quantum chemical calculations of the light-induced switching processes correlate these observations with the fundamentally different low-lying electronic states of the opened and closed forms and their comparably small modification by electron-withdrawing substituents. This full characterization of a molecular switch operated in a molecular junction is an important step toward the development of real molecular electronics devices.
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Affiliation(s)
- Torsten Sendler
- Helmholtz-Zentrum Dresden - Rossendorf Bautzner Landstraße 400 01328 Dresden Germany
| | | | - Matthias Wieser
- Helmholtz-Zentrum Dresden - Rossendorf Bautzner Landstraße 400 01328 Dresden Germany
| | - Lokamani
- Institute for Materials Science and Max Bergmann Center of Biomaterials Dresden Technische Universität Dresden 01062 Dresden Germany
| | - Jannic Wolf
- Fachbereich Chemie Universität Konstanz 78457 Konstanz Germany
| | - Manfred Helm
- Helmholtz-Zentrum Dresden - Rossendorf Bautzner Landstraße 40001328 Dresden Germany; Center for Advancing Electronics Dresden Technische Universität Dresden 01062 Dresden Germany
| | - Sibylle Gemming
- Helmholtz-Zentrum Dresden - Rossendorf Bautzner Landstraße 40001328 Dresden Germany; Faculty of Science Technische Universität Chemnitz 09107 Chemnitz Germany
| | - Jochen Kerbusch
- Helmholtz-Zentrum Dresden - Rossendorf Bautzner Landstraße 40001328 Dresden Germany; Center for Advancing Electronics Dresden Technische Universität Dresden 01062 Dresden Germany
| | - Elke Scheer
- Department of Physics Universität Konstanz 78457 Konstanz Germany
| | - Thomas Huhn
- Fachbereich Chemie Universität Konstanz 78457 Konstanz Germany
| | - Artur Erbe
- Helmholtz-Zentrum Dresden - Rossendorf Bautzner Landstraße 400 01328 Dresden Germany
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Abstract
Hexahydroindenes 10 are readily available in 3 steps with an overall yield of 41 – 45 % starting from the Hajos Wiechert ketone 1. Alkylation of the α,β-unsaturated ketone 1 at C-4 has been achieved by thioalkylation of the corresponding zinc dienolate 2 with α-chlorosulfides of type 3. Subsequent in situ reduction and desulfurization of the β-(phenylthio) ketones 4 leads directly to the 4-substituted hexahydroindene-5-ols 6 which can be deoxygenated via their mesylates to the hexahydroindenes 10.
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36
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Abstract
Double protonation (red) increases the ring-closing quantum yield Q⃑ of a molecular switch more than tenfold.
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Affiliation(s)
- Jannic Wolf
- Fachbereich Chemie
- Universität Konstanz
- D-78457 Konstanz
- Germany
| | - Thomas Huhn
- Fachbereich Chemie
- Universität Konstanz
- D-78457 Konstanz
- Germany
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37
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Kim D, Jeong H, Lee H, Hwang WT, Wolf J, Scheer E, Huhn T, Jeong H, Lee T. Flexible molecular-scale electronic devices composed of diarylethene photoswitching molecules. Adv Mater 2014; 26:3968-3973. [PMID: 24687399 DOI: 10.1002/adma.201306316] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 02/21/2014] [Indexed: 06/03/2023]
Affiliation(s)
- Dongku Kim
- Department of Physics and Astronomy and Institute of Applied Physics, Seoul National University, Seoul, 151-747, Korea
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Denger K, Weiss M, Felux AK, Schneider A, Mayer C, Spiteller D, Huhn T, Cook AM, Schleheck D. Sulphoglycolysis in Escherichia coli K-12 closes a gap in the biogeochemical sulphur cycle. Nature 2014; 507:114-7. [PMID: 24463506 DOI: 10.1038/nature12947] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 12/12/2013] [Indexed: 01/01/2023]
Abstract
Sulphoquinovose (SQ, 6-deoxy-6-sulphoglucose) has been known for 50 years as the polar headgroup of the plant sulpholipid in the photosynthetic membranes of all higher plants, mosses, ferns, algae and most photosynthetic bacteria. It is also found in some non-photosynthetic bacteria, and SQ is part of the surface layer of some Archaea. The estimated annual production of SQ is 10,000,000,000 tonnes (10 petagrams), thus it comprises a major portion of the organo-sulphur in nature, where SQ is degraded by bacteria. However, despite evidence for at least three different degradative pathways in bacteria, no enzymic reaction or gene in any pathway has been defined, although a sulphoglycolytic pathway has been proposed. Here we show that Escherichia coli K-12, the most widely studied prokaryotic model organism, performs sulphoglycolysis, in addition to standard glycolysis. SQ is catabolised through four newly discovered reactions that we established using purified, heterologously expressed enzymes: SQ isomerase, 6-deoxy-6-sulphofructose (SF) kinase, 6-deoxy-6-sulphofructose-1-phosphate (SFP) aldolase, and 3-sulpholactaldehyde (SLA) reductase. The enzymes are encoded in a ten-gene cluster, which probably also encodes regulation, transport and degradation of the whole sulpholipid; the gene cluster is present in almost all (>91%) available E. coli genomes, and is widespread in Enterobacteriaceae. The pathway yields dihydroxyacetone phosphate (DHAP), which powers energy conservation and growth of E. coli, and the sulphonate product 2,3-dihydroxypropane-1-sulphonate (DHPS), which is excreted. DHPS is mineralized by other bacteria, thus closing the sulphur cycle within a bacterial community.
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Affiliation(s)
- Karin Denger
- Department of Biology, University of Konstanz, D-78457 Konstanz, Germany
| | - Michael Weiss
- Konstanz Research School Chemical Biology, University of Konstanz, D-78457 Konstanz, Germany
| | - Ann-Katrin Felux
- Konstanz Research School Chemical Biology, University of Konstanz, D-78457 Konstanz, Germany
| | - Alexander Schneider
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, D-72076 Tübingen, Germany
| | - Christoph Mayer
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, D-72076 Tübingen, Germany
| | - Dieter Spiteller
- Department of Biology, University of Konstanz, D-78457 Konstanz, Germany
| | - Thomas Huhn
- Department of Chemistry, University of Konstanz, D-78457 Konstanz, Germany
| | - Alasdair M Cook
- Department of Biology, University of Konstanz, D-78457 Konstanz, Germany
| | - David Schleheck
- Department of Biology, University of Konstanz, D-78457 Konstanz, Germany
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Affiliation(s)
- Jannic Wolf
- Fachbereich Chemie, Universität Konstanz, D-78457 Konstanz, Germany
| | - Iris Eberspächer
- Fachbereich Chemie, Universität Konstanz, D-78457 Konstanz, Germany
| | - Ulrich Groth
- Fachbereich Chemie, Universität Konstanz, D-78457 Konstanz, Germany
| | - Thomas Huhn
- Fachbereich Chemie, Universität Konstanz, D-78457 Konstanz, Germany
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Sysoiev D, Yushchenko T, Scheer E, Groth U, Steiner UE, Exner TE, Huhn T. Pronounced effects on switching efficiency of diarylcycloalkenes upon cycloalkene ring contraction. Chem Commun (Camb) 2013; 48:11355-7. [PMID: 23073076 DOI: 10.1039/c2cc35726g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Several difurylperfluorocyclobutenes showing reversible photochromism were synthesized. In comparison to their cyclopentene homologues they show enhanced quantum yields for ring opening but reduced quantum yields for ring closure. X-ray structure analysis and quantum chemical calculations provide a conclusive explanation for such a behaviour.
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Affiliation(s)
- Dmytro Sysoiev
- Fachbereich Chemie, Universität Konstanz, D-78457 Konstanz, Germany
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Briechle BM, Kim Y, Ehrenreich P, Erbe A, Sysoiev D, Huhn T, Groth U, Scheer E. Current-voltage characteristics of single-molecule diarylethene junctions measured with adjustable gold electrodes in solution. Beilstein J Nanotechnol 2012; 3:798-808. [PMID: 23365792 PMCID: PMC3554105 DOI: 10.3762/bjnano.3.89] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2012] [Accepted: 11/12/2012] [Indexed: 06/01/2023]
Abstract
We report on an experimental analysis of the charge transport through sulfur-free photochromic molecular junctions. The conductance of individual molecules contacted with gold electrodes and the current-voltage characteristics of these junctions are measured in a mechanically controlled break-junction system at room temperature and in liquid environment. We compare the transport properties of a series of molecules, labeled TSC, MN, and 4Py, with the same switching core but varying side-arms and end-groups designed for providing the mechanical and electrical contact to the gold electrodes. We perform a detailed analysis of the transport properties of TSC in its open and closed states. We find rather broad distributions of conductance values in both states. The analysis, based on the assumption that the current is carried by a single dominating molecular orbital, reveals distinct differences between both states. We discuss the appearance of diode-like behavior for the particular species 4Py that features end-groups, which preferentially couple to the metal electrode by physisorption. We show that the energetic position of the molecular orbital varies as a function of the transmission. Finally, we show for the species MN that the use of two cyano end-groups on each side considerably enhances the coupling strength compared to the typical behavior of a single cyano group.
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Affiliation(s)
- Bernd M Briechle
- Physics Department, University of Konstanz, D-78457 Konstanz, Germany
| | - Youngsang Kim
- Physics Department, University of Konstanz, D-78457 Konstanz, Germany
| | | | - Artur Erbe
- Institute of Ion Beam Physics and Materials Research, Helmholtzzentrum Dresden-Rossendorf, D-01328 Dresden, Germany
| | - Dmytro Sysoiev
- Chemistry Department, University of Konstanz, D-78457 Konstanz, Germany
| | - Thomas Huhn
- Chemistry Department, University of Konstanz, D-78457 Konstanz, Germany
| | - Ulrich Groth
- Chemistry Department, University of Konstanz, D-78457 Konstanz, Germany
| | - Elke Scheer
- Physics Department, University of Konstanz, D-78457 Konstanz, Germany
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Kim Y, Hellmuth TJ, Sysoiev D, Pauly F, Pietsch T, Wolf J, Erbe A, Huhn T, Groth U, Steiner UE, Scheer E. Charge transport characteristics of diarylethene photoswitching single-molecule junctions. Nano Lett 2012; 12:3736-42. [PMID: 22734823 DOI: 10.1021/nl3015523] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
We report on the experimental analysis of the charge transport through single-molecule junctions of the open and closed isomers of photoswitching molecules. Sulfur-free diarylethene molecules are developed and studied via electrical and optical measurements as well as density functional theory calculations. The single-molecule conductance and the current-voltage characteristics are measured in a mechanically controlled break-junction system at low temperatures. Comparing the results with the single-level transport model, we find an unexpected behavior of the current-dominating molecular orbital upon isomerization. We show that both the side chains and end groups of the molecules are crucial to understand the charge transport mechanism of photoswitching molecular junctions.
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Affiliation(s)
- Youngsang Kim
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
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Denger K, Huhn T, Hollemeyer K, Schleheck D, Cook AM. Sulfoquinovose degraded by pure cultures of bacteria with release of C3-organosulfonates: complete degradation in two-member communities. FEMS Microbiol Lett 2012; 328:39-45. [PMID: 22150877 DOI: 10.1111/j.1574-6968.2011.02477.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Revised: 11/28/2011] [Accepted: 11/28/2011] [Indexed: 11/29/2022] Open
Abstract
Sulfoquinovose (SQ, 6-deoxy-6-sulfoglucose) was synthesized chemically. An HPLC-ELSD method to separate SQ and other chromophore-free sulfonates, e.g. 2,3-dihydroxypropane-1-sulfonate (DHPS), was developed. A set of 10 genome-sequenced, sulfonate-utilizing bacteria did not utilize SQ, but an isolate, Pseudomonas putida SQ1, from an enrichment culture did so. The molar growth yield with SQ was half of that with glucose, and 1 mol 3-sulfolactate (mol SQ)(-1) was formed during growth. The 3-sulfolactate was degraded by the addition of Paracoccus pantotrophus NKNCYSA, and the sulfonate sulfur was recovered quantitatively as sulfate. Another isolate, Klebsiella oxytoca TauN1, could utilize SQ, forming 1 mol DHPS (mol SQ)(-1) ; the molar growth yield with SQ was half of that with glucose. This DHPS could be degraded by Cupriavidus pinatubonensis JMP134, with quantitative recovery of the sulfonate sulfur as sulfate. We presume that SQ can be degraded by communities in the environment.
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Affiliation(s)
- Karin Denger
- Department of Biology, University of Konstanz, Konstanz, Germany
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Immel TA, Grützke M, Späte AK, Groth U, Öhlschläger P, Huhn T. Synthesis and X-ray structure analysis of a heptacoordinate titanium(iv)-bis-chelate with enhanced in vivo antitumor efficacy. Chem Commun (Camb) 2012; 48:5790-2. [DOI: 10.1039/c2cc31624b] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Immel TA, Grützke M, Batroff E, Groth U, Huhn T. Cytotoxic dinuclear titanium-salan complexes: structural and biological characterization. J Inorg Biochem 2011; 106:68-75. [PMID: 22112842 DOI: 10.1016/j.jinorgbio.2011.08.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 08/24/2011] [Accepted: 08/26/2011] [Indexed: 11/24/2022]
Abstract
Controlled hydrolysis of donor-substituted titanium-salan complexes led to the formation of well-defined dinuclear complexes. Structure determination by means of X-ray and NMR-studies revealed the presence of a single μ-oxo bridge and one labile alkoxide ligand per titanium center. Concomitant cytotoxicity assays of the isolated dinuclear complexes showed cytotoxicities in the low micro-molar region, surpassing in this respect even their monomeric ancestors, thus making them possible highly active metabolites of titanium-salan anti-cancer drugs.
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Affiliation(s)
- Timo A Immel
- Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Konstanz, Germany
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46
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Sysoiev D, Fedoseev A, Kim Y, Exner TE, Boneberg J, Huhn T, Leiderer P, Scheer E, Groth U, Steiner UE. Synthesis and Photoswitching Studies of Difurylperfluorocyclopentenes with Extended π-Systems. Chemistry 2011; 17:6663-72. [DOI: 10.1002/chem.201003716] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Indexed: 11/07/2022]
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Abstract
To discover chemical probes to further under-stand the function of individual DNA polymerases, we established a generally applicable high-throughput screening. By applying this technique we discovered three novel inhibitor classes of human DNA polymerase λ (DNA Pol λ), a key enzyme to maintain the genetic integrity of the genome. The rhodanines, classified as an excellent drug scaffold, were found to be the most potent inhibitors for DNA Pol λ. Importantly, they are up to 10 times less active against the highly similar DNA polymerase β. We investigated basic structure activity relationships. Furthermore, the rhodanines showed pharmacological activity in two human cancer cell lines. So the here reported small molecules could serve as useful DNA Pol λ probes and might serve as starting point to develop novel therapeutic agents.
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Affiliation(s)
- Tobias Strittmatter
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
| | - Bettina Bareth
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
| | - Timo A. Immel
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
| | - Thomas Huhn
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
| | - Thomas U. Mayer
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
| | - Andreas Marx
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
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Immel TA, Groth U, Huhn T, Öhlschläger P. Titanium salan complexes displays strong antitumor properties in vitro and in vivo in mice. PLoS One 2011; 6:e17869. [PMID: 21445304 PMCID: PMC3061874 DOI: 10.1371/journal.pone.0017869] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Accepted: 02/11/2011] [Indexed: 01/27/2023] Open
Abstract
The anticancer activity of titanium complexes has been known since the groundbreaking studies of Köpf and Köpf-Maier on titanocen dichloride. Unfortunately, possibly due to their fast hydrolysis, derivatives of titanocen dichloride failed in clinical studies. Recently, the new family of titanium salan complexes containing tetradentate ONNO ligands with anti-cancer properties has been discovered. These salan complexes are much more stabile in aqueous media. In this study we describe the biological activity of two titanium salan complexes in a mouse model of cervical cancer. High efficiency of this promising complex family was demonstrated for the first time in vivo. From these data we conclude that titanium salan complexes display very strong antitumor properties exhibiting only minor side effects. Our results may influence the chemotherapy with metallo therapeutics in the future.
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Affiliation(s)
- Timo A Immel
- Department of Chemistry and Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
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Immel TA, Martin JT, Dürr CJ, Groth U, Huhn T. Dimethyl titanocene Y: A valuable precursor for libraries of cytotoxic titanocene derivatives. J Inorg Biochem 2010; 104:863-7. [DOI: 10.1016/j.jinorgbio.2010.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Revised: 04/06/2010] [Accepted: 04/08/2010] [Indexed: 11/28/2022]
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Zotti LA, Kirchner T, Cuevas JC, Pauly F, Huhn T, Scheer E, Erbe A. Revealing the role of anchoring groups in the electrical conduction through single-molecule junctions. Small 2010; 6:1529-35. [PMID: 20578111 DOI: 10.1002/smll.200902227] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A combined experimental and theoretical study is presented revealing the influence of metal-molecule coupling on electronic transport through single-molecule junctions. Transport experiments through tolane molecules attached to gold electrodes via thiol, nitro, and cyano anchoring groups are performed. By fitting the experimental current-voltage characteristics to a single-level tunneling model, we extract both the position of the molecular orbital closest to the Fermi energy and the strength of the metal-molecule coupling. The values found for these parameters are rationalized with the help of density-functional-theory-based transport calculations. In particular, these calculations show that the anchoring groups determine the junction conductance by controlling not only the strength of the coupling to the metal but also the position of the relevant molecular energy levels.
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Affiliation(s)
- Linda A Zotti
- Departamento de Física Teórica de la Materia Condensada Universidad Autónoma de Madrid 28049 Madrid, Spain
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