1
|
Sieroka N, Lossau T, Neudecker T. Emergent Properties in Chemistry - Relating Molecular Properties to Bulk Behavior. Chemistry 2024; 30:e202303868. [PMID: 38558443 DOI: 10.1002/chem.202303868] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Indexed: 04/04/2024]
Abstract
Certain properties of an object only emerge when a sufficient number of those objects are present in a definite arrangement. For example, one or two water molecules cannot said to be in a liquid state, but a drop of water can be. This concept of emergence has been studied extensively, but only occasionally discussed explicitly in the context of chemistry. In this paper, we aim to show the fruitfulness of the concept of emergence for chemical inquiry by considering four case studies of emergent chemical properties, i. e., the liquidity and freezing of water, structural properties of crystals, thermodynamical phase transitions and quantum mechanical phenomena. We show that some of these properties emerge gradually, some at discrete points, and some should be taken to emerge only when the number of constituents tends to infinity. We argue that studying the way in which chemical properties emerge presents a useful avenue for research that promises greater insight into the nature of those properties.
Collapse
Affiliation(s)
- Norman Sieroka
- University of Bremen, Institute for Philosophy, Enrique-Schmidt-Straße 7, D-28359, Bremen, Germany
- ETH Zurich, Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg, CH-8093, Zurich, Switzerland
| | - Tammo Lossau
- University of Bremen, Institute for Philosophy, Enrique-Schmidt-Straße 7, D-28359, Bremen, Germany
| | - Tim Neudecker
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359, Bremen, Germany
- Bremen Center for Computational Materials Science, Am Fallturm 1, D-28359, Bremen, Germany
- MAPEX Center for Materials and Processes, Bibliothekstraße 1, D-28359, Bremen, Germany
| |
Collapse
|
2
|
Wang H, Benter S, Dononelli W, Neudecker T. JEDI: A versatile code for strain analysis of molecular and periodic systems under deformation. J Chem Phys 2024; 160:152501. [PMID: 38639312 DOI: 10.1063/5.0199247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/07/2024] [Indexed: 04/20/2024] Open
Abstract
Stretching or compression can induce significant energetic, geometric, and spectroscopic changes in materials. To fully exploit these effects in the design of mechano- or piezo-chromic materials, self-healing polymers, and other mechanoresponsive devices, a detailed knowledge about the distribution of mechanical strain in the material is essential. Within the past decade, Judgement of Energy DIstribution (JEDI) analysis has emerged as a useful tool for this purpose. Based on the harmonic approximation, the strain energy in each bond length, bond angle, and dihedral angle of the deformed system is calculated using quantum chemical methods. This allows the identification of the force-bearing scaffold of the system, leading to an understanding of mechanochemical processes at the most fundamental level. Here, we present a publicly available code that generalizes the JEDI analysis, which has previously only been available for isolated molecules. Now, the code has been extended to two- and three-dimensional periodic systems, supramolecular clusters, and substructures of chemical systems under various types of deformation. Due to the implementation of JEDI into the Atomic Simulation Environment, the JEDI analysis can be interfaced with a plethora of program packages that allow the calculation of electronic energies for molecular systems and systems with periodic boundary conditions. The automated generation of a color-coded three-dimensional structure via the Visual Molecular Dynamics program allows insightful visual analyses of the force-bearing scaffold of the strained system.
Collapse
Affiliation(s)
- Henry Wang
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
| | - Sanna Benter
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
| | - Wilke Dononelli
- Hybrid Materials Interfaces Group, Am Fallturm 1, D-28359 Bremen, Germany
- Bremen Center for Computational Materials Science, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX Center for Materials and Processes, Bibliothekstraße 1, D-28359 Bremen, Germany
| | - Tim Neudecker
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
- Bremen Center for Computational Materials Science, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX Center for Materials and Processes, Bibliothekstraße 1, D-28359 Bremen, Germany
| |
Collapse
|
3
|
Pracht P, Grimme S, Bannwarth C, Bohle F, Ehlert S, Feldmann G, Gorges J, Müller M, Neudecker T, Plett C, Spicher S, Steinbach P, Wesołowski PA, Zeller F. CREST-A program for the exploration of low-energy molecular chemical space. J Chem Phys 2024; 160:114110. [PMID: 38511658 DOI: 10.1063/5.0197592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Accepted: 02/29/2024] [Indexed: 03/22/2024] Open
Abstract
Conformer-rotamer sampling tool (CREST) is an open-source program for the efficient and automated exploration of molecular chemical space. Originally developed in Pracht et al. [Phys. Chem. Chem. Phys. 22, 7169 (2020)] as an automated driver for calculations at the extended tight-binding level (xTB), it offers a variety of molecular- and metadynamics simulations, geometry optimization, and molecular structure analysis capabilities. Implemented algorithms include automated procedures for conformational sampling, explicit solvation studies, the calculation of absolute molecular entropy, and the identification of molecular protonation and deprotonation sites. Calculations are set up to run concurrently, providing efficient single-node parallelization. CREST is designed to require minimal user input and comes with an implementation of the GFNn-xTB Hamiltonians and the GFN-FF force-field. Furthermore, interfaces to any quantum chemistry and force-field software can easily be created. In this article, we present recent developments in the CREST code and show a selection of applications for the most important features of the program. An important novelty is the refactored calculation backend, which provides significant speed-up for sampling of small or medium-sized drug molecules and allows for more sophisticated setups, for example, quantum mechanics/molecular mechanics and minimum energy crossing point calculations.
Collapse
Affiliation(s)
- Philipp Pracht
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Christoph Bannwarth
- Institute for Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52056 Aachen, Germany
| | - Fabian Bohle
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Sebastian Ehlert
- AI4Science, Microsoft Research, Evert van de Beekstraat 354, 1118 CZ Schiphol, The Netherlands
| | - Gereon Feldmann
- Institute for Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52056 Aachen, Germany
| | - Johannes Gorges
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Marcel Müller
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Tim Neudecker
- Institute for Physical and Theoretical Chemistry, University of Bremen, 28359 Bremen, Germany
| | - Christoph Plett
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | | | - Pit Steinbach
- Institute for Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52056 Aachen, Germany
| | - Patryk A Wesołowski
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Felix Zeller
- Institute for Physical and Theoretical Chemistry, University of Bremen, 28359 Bremen, Germany
| |
Collapse
|
4
|
Weiß R, Zeller F, Neudecker T. Calculating high-pressure vibrational frequencies analytically with the extended hydrostatic compression force field approach. J Chem Phys 2024; 160:084101. [PMID: 38385509 DOI: 10.1063/5.0189887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/25/2024] [Indexed: 02/23/2024] Open
Abstract
We report the implementation of the analytical Hessian for the mechanochemical extended hydrostatic compression force field method in the Q-Chem program package. To verify the implementation, the analytical Hessian was compared with finite difference calculations. In addition, we calculated the pressure dependency of the Raman active vibrational modes of methane, ethane, and hydrogen, as well as all IR and Raman active modes of Buckminsterfullerene, and compared the results with experimental and theoretical data. Our implementation paves the way for the analysis of geometric points on a pressure-deformed potential energy surface and provides a straightforward model to calculate the vibrational properties of molecules under high pressure.
Collapse
Affiliation(s)
- Rahel Weiß
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
| | - Felix Zeller
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
| | - Tim Neudecker
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
- Bremen Center for Computational Materials Science, University of Bremen, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstraße 1, D-28359 Bremen, Germany
| |
Collapse
|
5
|
Appiarius Y, Míguez-Lago S, Puylaert P, Wolf N, Kumar S, Molkenthin M, Miguel D, Neudecker T, Juríček M, Campaña AG, Staubitz A. Boosting quantum yields and circularly polarized luminescence of penta- and hexahelicenes by doping with two BN-groups. Chem Sci 2024; 15:466-476. [PMID: 38179512 PMCID: PMC10762774 DOI: 10.1039/d3sc02685j] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 10/23/2023] [Indexed: 01/06/2024] Open
Abstract
The incorporation of boron-nitrogen (BN) units into polycyclic aromatic hydrocarbons (PAHs) as an isoelectronic replacement of two carbon atoms can significantly improve their optical properties, while the geometries are mostly retained. We report the first non-π-extended penta- and hexahelicenes comprising two aromatic 1,2-azaborinine rings. Comparing them with their all-carbon analogs regarding structural, spectral and (chir)optical properties allowed us to quantify the impact of the heteroatoms. In particular, BN-hexahelicene BN[6] exhibited a crystal structure congruent with its analog CC[6], but displayed a fivefold higher fluorescence quantum yield (φfl = 0.17) and an outstanding luminescence dissymmetry factor (|glum| = 1.33 × 10-2). Such an unusual magnification of both properties at the same time makes BN-helicenes suitable candidates as circularly polarized luminescence emitters for applications in materials science.
Collapse
Affiliation(s)
- Yannik Appiarius
- University of Bremen, Institute for Organic and Analytical Chemistry 28359 Bremen Germany
- University of Bremen, MAPEX Center for Materials and Processes 28359 Bremen Germany
| | - Sandra Míguez-Lago
- University of Granada, Department of Organic Chemistry, Unidad de Excelencia de Química 18071 Granada Spain
| | - Pim Puylaert
- University of Bremen, Institute for Inorganic Chemistry and Crystallography 28359 Bremen Germany
| | - Noah Wolf
- University of Bremen, Institute for Organic and Analytical Chemistry 28359 Bremen Germany
| | - Sourabh Kumar
- University of Bremen, Institute for Physical and Theoretical Chemistry 28359 Bremen Germany
| | - Martin Molkenthin
- University of Bremen, Institute for Organic and Analytical Chemistry 28359 Bremen Germany
| | - Delia Miguel
- University of Granada, Department of Physical Chemistry, Unidad de Excelencia de Química 18071 Granada Spain
| | - Tim Neudecker
- University of Bremen, MAPEX Center for Materials and Processes 28359 Bremen Germany
- University of Bremen, Institute for Physical and Theoretical Chemistry 28359 Bremen Germany
- University of Bremen, Bremen Center for Computational Materials Science 28359 Bremen Germany
| | - Michal Juríček
- University of Zurich, Department of Chemistry 8057 Zurich Switzerland
| | - Araceli G Campaña
- University of Granada, Department of Organic Chemistry, Unidad de Excelencia de Química 18071 Granada Spain
| | - Anne Staubitz
- University of Bremen, Institute for Organic and Analytical Chemistry 28359 Bremen Germany
- University of Bremen, MAPEX Center for Materials and Processes 28359 Bremen Germany
| |
Collapse
|
6
|
Gliese PJ, Appiarius Y, Scheele T, Lork E, Neudecker T, Staubitz A. Synthesis and crystal structure of 2-(anthracen-9-yl)-1-( tert-butyl-dimethyl-sil-yl)-3,6-di-hydro-1λ 4,2λ 4-aza-borinine. Acta Crystallogr E Crystallogr Commun 2023; 79:1012-1016. [PMID: 37936862 PMCID: PMC10626957 DOI: 10.1107/s2056989023008381] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 09/23/2023] [Indexed: 11/09/2023]
Abstract
The title compound, C24H30BNSi (I), is an asymmetric 1,2,3,6-tetra-hydro-1,2-aza-borinine consisting of a BN-substituted cyclo-hexa-diene analog with a B-anthracenyl substituent. A ring-closing metathesis with subsequent substitution of the obtained BCl 1,2-aza-borinine using anthracenyl lithium yielded the title compound I. The asymmetric unit (Z = 8) belongs to the ortho-rhom-bic space group Pbca and shows an elongated N-C bond compared to previously reported BN-1,4-cyclo-hexa-diene [Abbey et al. (2008 ▸) J. Am. Chem. Soc. 130, 7250-7252]. The primarily contributing surface inter-actions are H⋯H and C⋯H/H⋯C (as elucidated by Hirshfeld surface analysis) which are dominated by van der Waals forces. Moreover, the non-aromatic BN heterocycle and the protecting group exhibit intra- and inter-molecular C-H⋯π inter-actions, respectively, with the anthracenyl substituent.
Collapse
Affiliation(s)
- Philipp J. Gliese
- University of Bremen, Institute for Organic and Analytical Chemistry, 28359 Bremen, Germany
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
| | - Yannik Appiarius
- University of Bremen, Institute for Organic and Analytical Chemistry, 28359 Bremen, Germany
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
| | - Tarek Scheele
- University of Bremen, Institute for Physical and Theoretical Chemistry, 28359 Bremen, Germany
| | - Enno Lork
- University of Bremen, Institute for Inorganic Chemistry and Crystallography, 28359 Bremen, Germany
| | - Tim Neudecker
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute for Physical and Theoretical Chemistry, 28359 Bremen, Germany
- Bremen Center for Computational Materials Science, 28359 Bremen, Germany
| | - Anne Staubitz
- University of Bremen, Institute for Organic and Analytical Chemistry, 28359 Bremen, Germany
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
| |
Collapse
|
7
|
Scheele T, Neudecker T. Using oriented external electric fields to manipulate rupture forces of mechanophores. Phys Chem Chem Phys 2023; 25:28070-28077. [PMID: 37823201 DOI: 10.1039/d3cp03965j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
Abstract
Oriented external electric fields (OEEFs) can facilitate chemical reactions by selectively weakening bonds. This makes them a topic of interest in mechanochemistry, where mechanical force is used to rupture specific bonds in molecules. Using electronic structure calculations based on density functional theory (DFT), we investigate the effect of OEEFs on the mechanical force required to activate mechanophores. We demonstrate that OEEFs can greatly lower the rupture force of mechanophores, and that the degree of this effect highly depends on the angle relative to the mechanical force at which the field is being applied. The greatest lowering of the rupture force does not always occur at the point of perfect alignment between OEEF and the vector of mechanical force. Using natural bond orbital analysis, we show that mechanical force amplifies the effect that an OEEF has on the scissile bond of a mechanophore. By combining methods to simulate molecules in OEEFs with methods applying mechanical force, we present an effective tool for analyzing mechanophores in OEEFs and show that computationally determining optimal OEEFs for mechanophore activation can assist in the development of future experimental studies.
Collapse
Affiliation(s)
- Tarek Scheele
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany.
| | - Tim Neudecker
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany.
- Bremen Center for Computational Materials Science, University of Bremen, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstraße 1, D-28359 Bremen, Germany
| |
Collapse
|
8
|
Scheele T, Neudecker T. Investigating the accuracy of density functional methods for molecules in electric fields. J Chem Phys 2023; 159:124111. [PMID: 38127387 DOI: 10.1063/5.0164372] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 09/05/2023] [Indexed: 12/23/2023] Open
Abstract
The use of oriented external electric fields (OEEFs) as a potential tool for catalyzing chemical reactions has gained traction in recent years. Electronic structure calculations using OEEFs are commonly done using methods based on density functional theory (DFT), but until now, the performance of DFT methods for calculating molecules in OEEFs had not been assessed in a more general scope. Looking at the accuracy of molecular geometries, electronic energies, and electric dipole moments compared to accurate coupled-cluster with perturbative triples data, we have investigated a wide variety of density functionals using different basis sets to determine how well the individual functionals perform on various types of chemical bonds. We found that most functionals accurately calculate geometries in OEEFs and that small basis sets are sufficient in many cases. Calculations of electronic energies show a significant error introduced by the OEEF, which the use of a larger basis set helps mitigate. Our findings show that DFT methods can be used for accurate calculations in OEEFs, allowing researchers to make full use of the advantages that they bring.
Collapse
Affiliation(s)
- Tarek Scheele
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße NW2, D-28359 Bremen, Germany
| | - Tim Neudecker
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße NW2, D-28359 Bremen, Germany
- Bremen Center for Computational Materials Science, University of Bremen, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstraße 1, D-28359 Bremen, Germany
| |
Collapse
|
9
|
Wong J, Ganoe B, Liu X, Neudecker T, Lee J, Liang J, Wang Z, Li J, Rettig A, Head-Gordon T, Head-Gordon M. An in-silico NMR laboratory for nuclear magnetic shieldings computed via finite fields: Exploring nucleus-specific renormalizations of MP2 and MP3. J Chem Phys 2023; 158:164116. [PMID: 37114707 PMCID: PMC10148725 DOI: 10.1063/5.0145130] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
We developed and implemented a method-independent, fully numerical, finite difference approach to calculating nuclear magnetic resonance shieldings, using gauge-including atomic orbitals. The resulting capability can be used to explore non-standard methods, given only the energy as a function of finite-applied magnetic fields and nuclear spins. For example, standard second-order Møller-Plesset theory (MP2) has well-known efficacy for 1H and 13C shieldings and known limitations for other nuclei such as 15N and 17O. It is, therefore, interesting to seek methods that offer good accuracy for 15N and 17O shieldings without greatly increased compute costs, as well as exploring whether such methods can further improve 1H and 13C shieldings. Using a small molecule test set of 28 species, we assessed two alternatives: κ regularized MP2 (κ-MP2), which provides energy-dependent damping of large amplitudes, and MP2.X, which includes a variable fraction, X, of third-order correlation (MP3). The aug-cc-pVTZ basis was used, and coupled cluster with singles and doubles and perturbative triples [CCSD(T)] results were taken as reference values. Our κ-MP2 results reveal significant improvements over MP2 for 13C and 15N, with the optimal κ value being element-specific. κ-MP2 with κ = 2 offers a 30% rms error reduction over MP2. For 15N, κ-MP2 with κ = 1.1 provides a 90% error reduction vs MP2 and a 60% error reduction vs CCSD. On the other hand, MP2.X with a scaling factor of 0.6 outperformed CCSD for all heavy nuclei. These results can be understood as providing renormalization of doubles amplitudes to partially account for neglected triple and higher substitutions and offer promising opportunities for future applications.
Collapse
Affiliation(s)
- Jonathan Wong
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Brad Ganoe
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Xiao Liu
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Tim Neudecker
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Joonho Lee
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Jiashu Liang
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Zhe Wang
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Jie Li
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Adam Rettig
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | | | | |
Collapse
|
10
|
Kumar S, Weiß R, Zeller F, Neudecker T. Trapping the Transition State in a [2,3]-Sigmatropic Rearrangement by Applying Pressure. ACS Omega 2022; 7:45208-45214. [PMID: 36530272 PMCID: PMC9753542 DOI: 10.1021/acsomega.2c05664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/10/2022] [Indexed: 06/17/2023]
Abstract
Transition states are of central importance in chemistry. While they are, by definition, transient species, it has been shown before that it is possible to "trap" transition states by applying stretching forces. We here demonstrate that the task of transforming the transition state of a chemical reaction into a minimum on the potential energy surface can be achieved using hydrostatic pressure. We apply the computational extended hydrostatic compression force field (X-HCFF) approach to the educt of a [2,3]-sigmatropic rearrangement in both static and dynamic calculations and find that the five-membered cyclic transition state of this reaction becomes a minimum at pressures in the range between 100 and 150 GPa. Born-Oppenheimer molecular dynamics (BOMD) simulations suggest that slow decompression leads to a 70:30 mix of the product and the educt of the sigmatropic rearrangement. Our findings are discussed in terms of geometric parameters and electronic rearrangements throughout the reaction. To provide reference data for experimental investigations, we simulated the IR, Raman, and time-resolved UV/vis absorption spectra for the educt, transition state, and product. We speculate that the trapping of transition states by using pressure is generally possible if the transition state of a chemical reaction has a more condensed geometry than both the educt and the product, which paves the way for new ways of initiating chemical reactions.
Collapse
Affiliation(s)
- Sourabh Kumar
- Institute
for Physical and Theoretical Chemistry, University of Bremen, Leobener Straße NW2, D-28359 Bremen, Germany
| | - Rahel Weiß
- Institute
for Physical and Theoretical Chemistry, University of Bremen, Leobener Straße NW2, D-28359 Bremen, Germany
| | - Felix Zeller
- Institute
for Physical and Theoretical Chemistry, University of Bremen, Leobener Straße NW2, D-28359 Bremen, Germany
| | - Tim Neudecker
- Institute
for Physical and Theoretical Chemistry, University of Bremen, Leobener Straße NW2, D-28359 Bremen, Germany
- Bremen
Center for Computational Materials Science, University of Bremen, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX
Center for Materials and Processes, University
of Bremen, Bibliothekstraße
1, D-28359 Bremen, Germany
| |
Collapse
|
11
|
Hsieh CM, Grabbet B, Zeller F, Benter S, Scheele T, Sieroka N, Neudecker T. Can a Finite Chain of Hydrogen Cyanide Molecules Model a Crystal? Chemphyschem 2022; 23:e202200414. [PMID: 35946306 PMCID: PMC10087120 DOI: 10.1002/cphc.202200414] [Citation(s) in RCA: 1] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 08/09/2022] [Indexed: 01/05/2023]
Abstract
When calculating structural or spectroscopic properties of molecular crystals, the question arises whether it is sufficient to simulate only a single molecule or a small molecular cluster or whether the simulation of the entire crystal is indispensable. In this work we juxtapose calculations on the high-pressure structural properties of the (periodic) HCN crystal and chains of HCN molecules of finite length. We find that, in most cases, the behavior of the crystal can be reproduced by computational methods simulating only around 15 molecules. The pressure-induced lengthening of the C-H bond in HCN found in calculations on both the periodic and finite material are explained in terms of orbital interaction. Our results pave the way for a more thorough understanding of high-pressure structural properties of materials and give incentives for the design of materials that expand under pressure. In addition, they shed light on the complementarity between calculations on periodic materials and systems of finite size.
Collapse
Affiliation(s)
- Chieh-Min Hsieh
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße NW2, D-28359, Bremen, Germany
| | - Björn Grabbet
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße NW2, D-28359, Bremen, Germany.,Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Felix Zeller
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße NW2, D-28359, Bremen, Germany
| | - Sanna Benter
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße NW2, D-28359, Bremen, Germany.,Present address: Bergische Universität Wuppertal, Gaußstraße 20, D-42119, Wuppertal, Germany
| | - Tarek Scheele
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße NW2, D-28359, Bremen, Germany
| | - Norman Sieroka
- University of Bremen, Theoretical Philosophy, Enrique-Schmidt-Straße 7, D-28359, Bremen, Germany
| | - Tim Neudecker
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße NW2, D-28359, Bremen, Germany.,Bremen Center for Computational Materials Science, Am Fallturm 1, D-28359, Bremen, Germany.,MAPEX Center for Materials and Processes, Bibliothekstraße 1, D-28359, Bremen, Germany
| |
Collapse
|
12
|
Schrey H, Scheele T, Ulonska C, Nedder DL, Neudecker T, Spiteller P, Stadler M. Alliacane-Type Secondary Metabolites from Submerged Cultures of the Basidiomycete Clitocybe nebularis. J Nat Prod 2022; 85:2363-2371. [PMID: 36130285 DOI: 10.1021/acs.jnatprod.2c00554] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Seven sesquiterpenoids, named nebucanes A-G (1-7), featuring a rare alliacane scaffold with unprecedented furan or pyrrole functions, were isolated from the fermentation broth of Clitocybe nebularis. Their structures were established on the basis of 1D/2D NMR spectroscopic analyses, HR-(+)-ESIMS spectra, and comparison of measured and calculated CD spectra for determination of the absolute configuration. Assessing the biological activities, nebucane D (4) exhibited antifungal effects against Rhodotorula glutinis, while nebucane G (7) displayed significant cytotoxicity against MCF-7 and A431 cell lines.
Collapse
Affiliation(s)
- Hedda Schrey
- Department of Microbial Drugs, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | - Tarek Scheele
- Institute for Physical and Theoretical Chemistry, University of Bremen, Leobener Straße NW2, D-28359 Bremen, Germany
| | - Conrad Ulonska
- Department of Microbial Drugs, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | - Dana Leoni Nedder
- Department of Microbial Drugs, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Inhoffenstraße 7, 38124 Braunschweig, Germany
- Department of Biotechnology, Technische Universität Braunschweig, Universitätsplatz 2, 38106 Braunschweig, Germany
| | - Tim Neudecker
- Institute for Physical and Theoretical Chemistry, University of Bremen, Leobener Straße NW2, D-28359 Bremen, Germany
- Bremen Center for Computational Materials Science, University of Bremen, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstraße 1, D-28359 Bremen, Germany
| | - Peter Spiteller
- Institute for Organic and Analytical Chemistry, University of Bremen, Leobener Straße 7, 28359 Bremen, Germany
| | - Marc Stadler
- Department of Microbial Drugs, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Inhoffenstraße 7, 38124 Braunschweig, Germany
- Institute of Microbiology, Technische Universität Braunschweig, Universitätsplatz 2, 38106 Braunschweig, Germany
| |
Collapse
|
13
|
Zeller F, Berquist E, Epifanovsky E, Neudecker T. An efficient implementation of the GOSTSHYP pressure model by applying shell-bounding gaussian 1-electron-3-center integral screening. J Chem Phys 2022; 157:184802. [DOI: 10.1063/5.0124067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We implemented a screening algorithm for one-electron-three-center (1e3c) overlap integrals over contracted gaussian-type orbitals (CGTOs) into the Q-Chem program package. The respective bounds were derived using shell-bounding gaussians (SBGs) and the Obara-Saika recurrence relations. Using integral screening, we reduced the computational scaling of the Gaussians On Surface Tesserae Simulate HYdrostatic Pressure (GOSTSHYP) model in terms of calculation time and memory usage to a linear relationship with the tesserae used to discretize the surface area. Further code improvements allowed for additional performance boosts. To demonstrate the better performance, we calculated the compressebility of fullerenes up to C180, where we were originally limited to C40 due to the high RAM usage of GOSTSHYP.
Collapse
Affiliation(s)
- Felix Zeller
- University of Bremen Faculty 02 Biology Chemistry, Germany
| | | | | | - Tim Neudecker
- Institute for Physical and Theoretical Chemistry, University of Bremen, Germany
| |
Collapse
|
14
|
Appiarius Y, Gliese PJ, Segler SAW, Rusch P, Zhang J, Gates PJ, Pal R, Malaspina LA, Sugimoto K, Neudecker T, Bigall NC, Grabowsky S, Bakulin AA, Staubitz A. BN-Substitution in Dithienylpyrenes Prevents Excimer Formation in Solution and in the Solid State. J Phys Chem C Nanomater Interfaces 2022; 126:4563-4576. [PMID: 35299818 PMCID: PMC8919264 DOI: 10.1021/acs.jpcc.1c08812] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Boron-nitrogen substitutions in polycyclic aromatic hydrocarbons (PAHs) have a strong impact on the optical properties of the molecules due to a significantly more heterogeneous electron distribution. However, besides these single-molecule properties, the observed optical properties of PAHs critically depend on the degree of intermolecular interactions such as π-π-stacking, dipolar interactions, or the formation of dimers in the excited state. Pyrene is the most prominent example showing the latter as it exhibits a broadened and strongly bathochromically shifted emission band at high concentrations in solution compared to the respective monomers. In the solid state, the impact of intermolecular interactions is even higher as it determines the crystal packing crucially. In this work, a thiophene-flanked BN-pyrene (BNP) was synthesized and compared with its all-carbon analogue (CCP) in solution and in the solid state by means of crystallography, NMR spectroscopy, UV-vis spectroscopy, and photoluminescence (PL) spectroscopy. In solution, PL spectroscopy revealed the solvent-dependent presence of excimers of CCP at high concentrations. In contrast, no excimers were found in BNP. Clear differences were also observed in the single-crystal packing motifs. While CCP revealed overlapped pyrene planes with centroid distances in the range of classical π-stacking interactions, the BNP scaffolds were displaced and significantly more spatially separated.
Collapse
Affiliation(s)
- Yannik Appiarius
- Institute
for Analytical and Organic Chemistry, University
of Bremen, Leobener Straße 7, D-28359 Bremen, Germany
- MAPEX
Center for Materials and Processes, University
of Bremen, Bibliothekstraße
1, D-28359 Bremen, Germany
| | - Philipp J. Gliese
- Institute
for Analytical and Organic Chemistry, University
of Bremen, Leobener Straße 7, D-28359 Bremen, Germany
- MAPEX
Center for Materials and Processes, University
of Bremen, Bibliothekstraße
1, D-28359 Bremen, Germany
| | - Stephan A. W. Segler
- Institute
for Analytical and Organic Chemistry, University
of Bremen, Leobener Straße 7, D-28359 Bremen, Germany
- MAPEX
Center for Materials and Processes, University
of Bremen, Bibliothekstraße
1, D-28359 Bremen, Germany
| | - Pascal Rusch
- Institute
of Physical Chemistry and Electrochemistry, Leibniz University Hannover, Callinstraße 3a, D-30167 Hannover, Germany
- Cluster
of Excellence PhoenixD (Photonics, Optics, and Engineering—Innovation
Across Disciplines), Leibniz University
Hannover, D-30167 Hannover, Germany
| | - Jiangbin Zhang
- Cavendish
Laboratory, University of Cambridge, 19 J J Thomson Avenue, CB3 0HE Cambridge, U.K.
- College of
Advanced Interdisciplinary Studies, National
University of Defense Technology, 410073 Changsha, Hunan, China
| | - Paul J. Gates
- School
of Chemistry, University of Bristol, Cantock’s Close, BS8 1TS Bristol, U.K.
| | - Rumpa Pal
- Institute
of Inorganic Chemistry and Crystallography, University of Bremen, Leobener Straße 7, D-28359 Bremen, Germany
| | - Lorraine A. Malaspina
- Institute
of Inorganic Chemistry and Crystallography, University of Bremen, Leobener Straße 7, D-28359 Bremen, Germany
- Department
of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Kunihisa Sugimoto
- Japan Synchrotron
Radiation Research Institute (JASRI), 1-1-1, Kouto, Sayo-cho, Hyogo 679-5198, Japan
| | - Tim Neudecker
- MAPEX
Center for Materials and Processes, University
of Bremen, Bibliothekstraße
1, D-28359 Bremen, Germany
- Institute for Physical and Theoretical
Chemistry, University of Bremen, Leobener Straße 7, D-28359 Bremen, Germany
- Bremen Center for Computational Materials
Science, University of Bremen, Am Fallturm 1, D-28359 Bremen, Germany
| | - Nadja C. Bigall
- Institute
of Physical Chemistry and Electrochemistry, Leibniz University Hannover, Callinstraße 3a, D-30167 Hannover, Germany
- Cluster
of Excellence PhoenixD (Photonics, Optics, and Engineering—Innovation
Across Disciplines), Leibniz University
Hannover, D-30167 Hannover, Germany
| | - Simon Grabowsky
- Institute
of Inorganic Chemistry and Crystallography, University of Bremen, Leobener Straße 7, D-28359 Bremen, Germany
- Department
of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Artem A. Bakulin
- Cavendish
Laboratory, University of Cambridge, 19 J J Thomson Avenue, CB3 0HE Cambridge, U.K.
- Department of Chemistry, Imperial College
London, Imperial College Rd, SW7 2AZ London, U.K.
| | - Anne Staubitz
- Institute
for Analytical and Organic Chemistry, University
of Bremen, Leobener Straße 7, D-28359 Bremen, Germany
- MAPEX
Center for Materials and Processes, University
of Bremen, Bibliothekstraße
1, D-28359 Bremen, Germany
| |
Collapse
|
15
|
Verhaegen Y, Monteyne E, Neudecker T, Tulp I, Smagghe G, Cooreman K, Roose P, Parmentier K. Organotins in North Sea brown shrimp (Crangon crangon L.) after implementation of the TBT ban. Chemosphere 2012; 86:979-984. [PMID: 22154339 DOI: 10.1016/j.chemosphere.2011.11.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 11/09/2011] [Accepted: 11/11/2011] [Indexed: 05/31/2023]
Abstract
The organotin (OT) compounds tributyltin (TBT) and triphenyltin (TPhT) are potent biocides that have been used ubiquitously in antifouling paints and pesticides since the mid-1970s. These biocides are extremely toxic to marine life, particularly marine gastropod populations. The European Union therefore took measures to reduce the use of TBT-based antifouling paints on ships and ultimately banned these paints in 2003. Despite sufficient data on OT concentrations in marine gastropods, data are scarce for other species such as the North Sea brown shrimp (Crangon crangon), a dominant crustacean species in North Sea inshore benthic communities. The present study provides the first spatial overview of OT concentrations in North Sea brown shrimp. We have compared these data with historical concentrations in shrimp as well as with sediment concentrations. We have also addressed the effect on the shrimp stock and any human health risks associated with the OT concentrations found. TBT and TPhT in shrimp tail muscle ranged from 4 to 124 and from 1 to 24 μg kg(-1) DW, respectively. High levels are accumulated in estuarine areas and are clearly related with sediment concentrations (biota-sediment accumulation factor ~10). Levels have decreased approximately 10-fold since the ban took effect, coinciding with a recovery of the shrimp stock after 30 years of gradual regression. Furthermore, the OT levels found in brown shrimp no longer present a human health risk.
Collapse
Affiliation(s)
- Y Verhaegen
- Institute for Agricultural and Fisheries Research (ILVO), Animal Sciences Unit, Fisheries, Ankerstraat 1, 8400 Ostend, Belgium
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Neudecker T. Das Phänomen der Hormone. Von G. Venzmer. Econ Verlag, Düsseldorf, Wien 1971. 1. Aufl., 286 S., zahlr. Abb., geb. DM 18,-. CHEM UNSERER ZEIT 2004. [DOI: 10.1002/ciuz.19720060506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
17
|
Affiliation(s)
- T Neudecker
- Institute of Toxicology, University of Würzburg, Germany
| |
Collapse
|
18
|
Neudecker T, Eder E, Deininger C, Henschler D. Mutagenicity of 2-methylacrolein, 2-ethylacrolein and 2-propylacrolein in Salmonella typhimurium TA100. A comparative study. Mutat Res 1991; 264:193-6. [PMID: 1723498 DOI: 10.1016/0165-7992(91)90077-h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The C2-alkylated acrolein derivatives 2-methylacrolein, 2-ethylacrolein and 2-propylacrolein are mutagenic in Salmonella typhimurium TA100. They are direct mutagens, their mutagenic potency being inversely proportional to the size of the alkylating substituent in the C2 position. In the presence of S9 mix, the mutagenicity of all these substances is considerably reduced; the reduction in mutagenicity is inversely proportional to the direct mutagenic potential of the substance. As shown for 2-methylacrolein, the reduction in mutagenicity is dependent on the concentration of S9 in the S9 mix and is not significantly influenced by heat inactivation of the S9 mix or by addition of TCPO, an inhibitor of epoxide hydrolase, to the testing system. There are no indications of enzymatic activation by the metabolizing microsomal system.
Collapse
Affiliation(s)
- T Neudecker
- Institute of Toxicology, University of Würzburg, Germany
| | | | | | | |
Collapse
|
19
|
Abstract
The mutagenic and genotoxic effects of ethylvinyl ketone were investigated. This alpha, beta-unsaturated carbonyl compound is widely distributed in the environment, in particular in food. Whereas ethylvinyl ketone shows only weak genotoxicity in the SOS Chromotest with Escherichia coli PQ37, it was distinctly mutagenic per se in the Salmonella preincubation assay with TA100. Using SKF 525 (an inhibitor of microsomal monooxygenase) and trichloropropene oxide (an inhibitor of epoxide hydrolase) we found indication for additional activation via epoxidation by S9 mix. The need for further investigation of the genotoxic, mutagenic and carcinogenic effects of this compound is strongly indicated.
Collapse
Affiliation(s)
- C Deininger
- Institute of Toxicology, University of Würzburg, FRG
| | | | | | | |
Collapse
|
20
|
Neudecker T, Eder E, Deininger C, Hoffman C, Henschler D. Mutagenicity of methylvinyl ketone in Salmonella typhimurium TA100--indication for epoxidation as an activation mechanism. Mutat Res 1989; 227:131-4. [PMID: 2677713 DOI: 10.1016/0165-7992(89)90009-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- T Neudecker
- Institute of Pharmacology and Toxicology, University of Würzburg, F.R.G
| | | | | | | | | |
Collapse
|
21
|
Vamvakas S, Kordowich FJ, Dekant W, Neudecker T, Henschler D. Mutagenicity of hexachloro-1,3-butadiene and its S-conjugates in the Ames test--role of activation by the mercapturic acid pathway in its nephrocarcinogenicity. Carcinogenesis 1988; 9:907-10. [PMID: 3286031 DOI: 10.1093/carcin/9.6.907] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The mutagenicity of hexachloro-1,3-butadiene and its S-conjugates 1-(glutathion-S-yl)-1,2,3,4,4-pentachloro-1,3-butadiene (GTB), 1,4-(bis-glutathion-S-yl-1,2,3,4-tetrachloro-1,3-butadiene (BGTB) and 1,4-(bis-cystein-S-yl)-1,2,3,4-tetrachloro-1,3-butadiene (BCTB) was investigated in Salmonella typhimurium TA100 using a modified preincubation assay. GTB was a direct-acting mutagen; the mutagenic potency of GTB was markedly enhanced by rat kidney microsomes or mitochondria and less so by cytosol. The bis-conjugates BGTB and BCTB were not mutagenic in the strains TA100, TA2638 and TA98. Purified HCBD was not mutagenic either without exogenous metabolic activation or with rat liver microsomes fortified with NADPH. Preincubation with rat liver microsomes and glutathione resulted in an unequivocal mutagenic activity of HCBD which was increased by additional inclusion of rat kidney microsomes. The cysteine conjugate beta-lyase inhibitor aminooxyacetic acid decreased the mutagenicity of HCBD and its S-conjugates. These results provide strong evidence that formation of the corresponding monoglutathione S-conjugate from HCBD and subsequent cleavage of this conjugate by gamma-glutamyltranspeptidase and beta-lyase may be responsible for the nephrocarcinogenicity of the parent compound in vivo, whereas formation of the bis-glutathione S-conjugate probably plays no role in the organ specific effects of HCBD.
Collapse
Affiliation(s)
- S Vamvakas
- Institut für Toxikologie, Universität Würzburg, FRG
| | | | | | | | | |
Collapse
|
22
|
Neudecker T, Henschler D. Mutagenicity of chloroolefins in the Salmonella/mammalian microsome test. III. Metabolic activation of the allylic chloropropenes allyl chloride, 1,3-dichloropropene, 2,3-dichloro-1-propene, 1,2,3-trichloropropene, 1,1,2,3-tetrachloro-2-propene and hexachloropropene by S9 mix via two different metabolic pathways. Mutat Res 1986; 170:1-9. [PMID: 3515164 DOI: 10.1016/0165-1218(86)90076-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In the presence of S9 mix all allylic chloropropenes tested exert considerable indirect mutagenic activity which is most pronounced for 1,2,3-trichloropropene. Lower as well as higher chlorinated derivatives are clearly less mutagenic. Longer than standard incubation time (120 min instead of 20 min) at 37 degrees C always leads to an increase in mutagenic activity. An increase in concentration of rat-liver homogenate fraction (S9) in the metabolising system (S9 mix) enhances mutagenicity only for 1,3-dichloropropene, 2,3-dichloro-1-propene and for the cis isomer of 1,1,2,3-tetrachloro-2-propene. According to the effects of the enzyme inhibitors SKF525 1,1,1-trichloropropene-2,3-oxide and cyanamide the allylic chloropropenes fall into 3 groups distinguished by their mode of metabolic activation by S9 mix: (a) allyl chloride and 1,3-dichloropropene are hydrolysed to the corresponding allylic alcohols which can be oxidised to the respective acroleins (hydrolytic-oxidative pathway); (b) 2,3-dichloro-1-propene, 1,1,2,3-tetrachloro-2-propene and hexachloropropene are epoxidised in the C=C double bond, giving rise to reactive epoxides (epoxidative pathway); (c) only 1,2,3-trichloropropene is obviously activated by both these alternative metabolic pathways. Structural parameters like chloro-substitution of the central C atom of the C=C-C sequence and substituent-induced polarisation of the C=C double bond as well as cis/trans isomerism might be responsible for different substrate properties for the enzymes involved in allylic chloropropene metabolism, thus determining different degrees of activation by either one or both pathways.
Collapse
|
23
|
Neudecker T, Dekant W, Jörns M, Eder E, Henschler D. Mutagenicity of chloroolefins in the Salmonella/mammalian microsome test--II. Structural requirements for the metabolic activation of non-allylic chloropropenes and methylated derivatives via epoxide formation. Biochem Pharmacol 1986; 35:195-200. [PMID: 3942595 DOI: 10.1016/0006-2952(86)90513-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Non-allylic chloropropenes and their methyl-homologues, being chloro-substituted exclusively in vinylic position, are mutagenic in the presence of metabolizing rat liver homogenate fraction (S9 mix). This can be interpreted as the result of polarizing inductive (I-) and mesomeric (M-) effects exerted by Cl- as well as by CH3-substituents on the olefinic double bond. The extent of their mutagenic activity increases with longer preincubation time and/or a higher concentration of rat liver homogenate fraction (S9) in the S9 mix. The only exception from this rule of a qualitative correlation of C = C-bond polarization due to asymmetric substitution and mutagenic activity is 1-chloro-2-methyl-1-propene which is non-mutagenic. In this case effects of a steric hindrance of two voluminous CH3-substituents attached to one C-atom of the C = C-bond might inhibit enzymatic attack of the double bond by microsomal oxygenase. Mutagenic activity is invariably decreased in the presence of SKF525, inhibitor of microsomal oxygenase, and increased when 1,1,1-trichloropropene-2,3-oxide (TCPO), inhibitor of epoxide hydrolase, is added to the test system. This is a strong argument for metabolic activation of these substances occurring via epoxide formation.
Collapse
|
24
|
Schiffmann D, Metzler M, Neudecker T, Henschler D. Morphological transformation of Syrian hamster embryo fibroblasts by the anabolic agent trenbolone. Arch Toxicol 1985; 58:59-63. [PMID: 3907591 DOI: 10.1007/bf00292619] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Trenbolone (TBOH), a synthetic androgen used as an anabolic agent in livestock, has been tested for mutagenicity in the Salmonella assay, for covalent DNA-binding in vitro, for induction of unscheduled DNA synthesis in HeLa cells and Syrian hamster embryo (SHE) fibroblasts and for morphological transformation of SHE cells. While TBOH gave negative results in the assays for mutagenicity and DNA damage, it was clearly capable of transforming SHE cells in culture. The natural androgen testosterone did not transform these cells. Thus, TBOH appears to be a substance which can transform cells independent of its hormonal action and without grossly damaging DNA.
Collapse
|
25
|
Neudecker T, Henschler D. Mutagenicity of chloro-olefins in the Salmonella/mammalian microsome test. I. Allyl chloride mutagenicity re-examined. Mutat Res 1985; 157:145-8. [PMID: 3894959 DOI: 10.1016/0165-1218(85)90109-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Contrary to findings published up to now, allyl chloride, a well known directly acting mutagen for Salmonella typhimurium, is efficiently activated by rat-liver homogenate (S9 mix) under non-standard mutagenicity testing conditions. Its indirect, S9-mediated mutagenic activity is greatly enhanced when longer than standard preincubation times are applied. The indirect mutagenicity of allyl chloride, thus revealed, greatly exceeds its direct mutagenic activity. Obviously, standard mutagenicity testing conditions cannot be regarded as reliable tools for the evaluation of the full genotoxic potential of allyl chloride and, possibly, of other related compounds.
Collapse
|
26
|
Abstract
Allyl isothiocyanate, a naturally occurring compound, component of oil of mustard and human food plants such as cabbage, cauliflower and horseradish, has up to now been regarded as nonmutagenic in bacterial mutagenicity testing systems. Recently, however, it was found to cause transitional-cell papillomas in the urinary bladder of male F344 rats. Contrary to earlier reports, in this study allyl isothiocyanate showed clear mutagenicity for Salmonella typhimurium TA100 in the preincubation assay after longer, non-standard preincubation times (greater than 20 min). The mutagenicity is expressed only in the presence of a rat-liver homogenate metabolising system, i.e. it is indirect. However, high concentrations of rat-liver homogenate suppress the mutagenicity of allyl isothiocyanate. SKF525, inhibitor of microsomal oxygenase, reduces the mutagenic potential which on the other hand is increased in the presence of 1,1,1-trichloropropene-2-oxide, inhibitor of epoxide hydrolase. This indicates the occurrence of an epoxide intermediate in allyl isothiocyanate metabolism. Another metabolic pathway, namely hydrolysis to allyl alcohol and oxidation to acrolein, a known mutagen, also seems possible as cyanamide, inhibitor of aldehyde dehydrogenase, can slightly increase the mutagenic potential. The reason(s) for allyl isothiocyanate's requirement for long preincubation times to express mutagenicity still requires elucidation, and the question arises: is allyl isothiocyanate a single, exceptional case or not?
Collapse
|
27
|
Abstract
Hexachloro(1,3)butadiene (HCBD) is a well known environmental contaminant. The nephrocarcinogenic potential of HCBD has been shown in long-term studies with rats. Experiments were performed to assist in determining whether this effect is mediated by epigenetic or genotoxic mechanisms and to compare the mutagenic properties of HCBD with those of its monooxidation products, perchloro-3-butenoic acid (PCBA) and perchloro-3-butenoic acid chloride (PCBAC), which are conceivable metabolites of HCBD. All 3 compounds are mutagenic to the Salmonella typhimurium tester strain TA100. The mutagenic effect is dose-dependent and parallels the chemical reactivity of the compounds. HCBD is only mutagenic in the presence of drug-metabolizing enzymes (S9 mix) with an increased protein content. The mutagenic response after incubation with PCBAC and PCBA is 2-3-fold that of HCBD. Additionally, both PCBAC and PCBA exert a mutagenic response in the absence of S9 mix. The experiments support the assumption of a genotoxic potential of HCBD.
Collapse
|
28
|
Abstract
Thirteen allylic compounds, mostly with close structural relationship, were tested for their ability to induce unscheduled DNA synthesis (UDS) in HeLa cells and mutations in the Ames test; 11 induced UDS in dose dependence. Allyl isothiocyanate was negative in UDS (borderline in the Ames test) and acrolein (positive in the Ames test) proved toxic to HeLa cells, therefore UDS measurement was excluded. In general, positive qualitative and quantitative correlation between UDS, Ames test and alkylating properties (as measured in the 4-nitrobenzyl-pyridine test, NBP) were found. Among structural analogs and typical allylic compounds with various leaving groups, the amount of induced DNA repair at equimolar concentrations decreased in the same order as the mutagenic and alkylating activities in the other 2 test systems: 1,3-dichloropropene (cis) greater than 1,3-dichloropropene (trans) greater than 2,3-dichloro-1-propene; 1-chloro-2-butene greater than 3-chloro-1-butene greater than 3-chloro-2-methyl-1-propene greater than allyl chloride; allyl-methane-sulfonate greater than -iodide greater than -bromide greater than -chloride.
Collapse
|
29
|
Eder E, Neudecker T, Schiffmann D, Henschler D. Structure-activity relationship of genotoxicity in allyl and allylic compounds: model experiments with three quick screening assays. Toxicol Lett 1983. [DOI: 10.1016/0378-4274(83)90520-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
30
|
Reichert D, Neudecker T, Spengler U, Henschler D. Mutagenicity of dichloroacetylene and its degradation products trichloroacetyl chloride, trichloroacryloyl chloride and hexachlorobutadiene. Mutat Res 1983; 117:21-9. [PMID: 6339907 DOI: 10.1016/0165-1218(83)90149-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Dichloroacetylene (DCA) is a highly reactive compound that decomposes rapidly in contact with air into a series of chlorinated aliphatic hydrocarbons (e.g., phosgene, trichloroacetyl chloride, trichloroacryloyl chloride and hexachlorobutadiene). Experiments were performed to compare the mutagenic properties of DCA and its degradation products on the histidine-dependent tester strains TA98 and TA100 of Salmonella typhimurium. In these experiments, DCA vapour was streamed under analytical control through the bacterial suspensions. DCA is soluble in aqueous solution and was stable under the experimental steady-state conditions of the bacterial exposure. There is a linear correlation between the supply of DCA vapour and solubilized DCA in the range of 1000 and 16 000 ppm. Mutagenic response was observed with strain TA100 if the bacteria were suspended in Oxoid medium. No mutagenicity could be detected with strain TA98. DCA mixtures with acetylene, as used as stabilizer for animal experiments, were not mutagenic in either bacterial strain, irrespective of the presence or absence of S9 mix in the cell suspension. One of the degradation products of DCA, trichloroacryloyl chloride, showed pronounced mutagenic properties with and without drug-metabolizing enzymes. Other degradation products of DCA, such as trichloroacetyl chloride and hexachlorobutadiene, were not mutagenic, either in the presence or absence of liver homogenate.
Collapse
|
31
|
Eder E, Henschler D, Neudecker T. Mutagenic properties of allylic and alpha, beta-unsaturated compounds: consideration of alkylating mechanisms. Xenobiotica 1982; 12:831-48. [PMID: 6763406 DOI: 10.3109/00498258209038955] [Citation(s) in RCA: 129] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
1. Allyl and allylic compounds may exert alkylating activities by SN1, SN2 and SN2' mechanisms. This direct alkylating potential can be determined quantitatively by a modified 4-NBP (4-nitrobenzyl pyridine) test. 2. The alkylating activities in a systematically selected series of allyl and allylic compounds correlate well with the direct mutagenic potential as determined in the Ames test using Salmonella typhimurium TA 100 as tester strain. 3. The allylic structure is a prerequisite for these types of activities since structurally related molecules lacking the allylic moiety are inactive in this respect. 4. The potency of both the alkylating and mutagenic activity is determined by the strength of the leaving group: --OSO2CH3 greater than I greater than Br greater than Cl greater than--NCS. 5. Indirect mutagenicity, through metabolic activation of the olefinic bond (by addition of S9 mix to the tester medium), can be ruled out for practically all compounds, the only exception found being 2,3-dichloro-1-propene where an increase of mutagenicity is encountered after addition of S9 mix; mechanistic explanations for this exception are provided. 6. Analogous activation is demonstrated for benzyl halides, the alkylating potency of which is even higher than that of genuine allylic compounds. 7. A variety of methyl- and chlorine-substituted allyl compounds has been included in the study: both groups increase activity, either by +I (CH3) or by +M effects (Cl). 8. alpha, beta-Unsaturated carbonyl compounds, e.g. acrolein and crotonaldehyde, also display direct mutagenic activity which is due to a completely different mechanism: covalent binding to nucleophilic sites of DNA bases by Michael addition. Methyl and other alkyl substitutions decrease the mutagenic potential in this type of compound. The corresponding alcohols, also displaying mutagenic activity but to a lesser degree, are metabolically activated by ADH (alcohol dehydrogenase) of the tester strain microbes to the aldehydes or ketones.
Collapse
|
32
|
Eder E, Neudecker T, Lutz D, Henschler D. Correlation of alkylating and mutagenic activities of allyl and allylic compounds: standard alkylation test vs. kinetic investigation. Chem Biol Interact 1982; 38:303-15. [PMID: 7037213 DOI: 10.1016/0009-2797(82)90060-6] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Thirty-nine allylic and non-allylic compounds have been tested in the standard 4-(p-nitrobenzyl)pyridine (NBP) alkylating procedure and the Salmonella typhimurium mutagenicity assay. Fourteen of these were found directly mutagenic (without addition of S-9 mix activating enzyme system). With twelve of these compounds, a good correlation of alkylating and mutagenic potencies was established; the remaining two do not meet the chemical conditions of the NBP procedure on account of HCl elimination with these two compounds. The other 25 substances were inactive in both systems. The quantitative correlation proved to be almost linear in the lower activity ranges (E approximately 2; revertants/muml approximately 600). The reasons for some deviations from the linear relationship have been analyzed and discussed on the basis of structural features. In addition to the standard alkylation test, a modified NBP-test was performed in order to obtain kinetic data and activation energy values. The results with 6 representative allylic compounds show that the overall correlation is not substantially improved above that of the standard procedure: nonetheless, additional information on reaction characteristics is obtained with some substances.
Collapse
|
33
|
|
34
|
Neudecker T, Lutz D, Eder E, Henschler D. Structure-activity relationship in halogen and alkyl substituted allyl and allylic compounds: correlation of alkylating and mutagenic properties. Biochem Pharmacol 1980; 29:2611-7. [PMID: 7000076 DOI: 10.1016/0006-2952(80)90075-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
35
|
Eder E, Neudecker T, Lutz D, Henschler D. Mutagenic potential of allyl and allylic compounds. Structure-activity relationship as determined by alkylating and direct in vitro mutagenic properties. Biochem Pharmacol 1980; 29:993-8. [PMID: 6992786 DOI: 10.1016/0006-2952(80)90161-6] [Citation(s) in RCA: 122] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
36
|
Abstract
The cis- and trans-isomers of 1,3-dichloropropene have been tested in the Ames mutagenicity assay system on Salmonella typhimurium tester strain TA 1535. Both isomers have been found to be mutagenic even without microsomal activation.
Collapse
|
37
|
Abstract
Technical trichloroethylene has been found carcinogenic in mice after high daily doses per os. A GC-MS analysis of this technical sample revealed the presence of considerable amounts of epichlorohydrin and 1.2-epoxibutane as stabilizers. These epoxides are highly mutagenic in the Ames test and are, most probably, responsible for the carcinogenic effect found in mice. The question whether trichloroethylene is carcinogenic or not remains open.
Collapse
|