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Zhang M, Nixon R, Schaufelberger F, Pirvu L, De Bo G, Leigh DA. Mechanical scission of a knotted polymer. Nat Chem 2024:10.1038/s41557-024-01510-3. [PMID: 38649468 DOI: 10.1038/s41557-024-01510-3] [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: 11/13/2022] [Accepted: 03/18/2024] [Indexed: 04/25/2024]
Abstract
Molecular knots and entanglements form randomly and spontaneously in both biological and synthetic polymer chains. It is known that macroscopic materials, such as ropes, are substantially weakened by the presence of knots, but until now it has been unclear whether similar behaviour occurs on a molecular level. Here we show that the presence of a well-defined overhand knot in a polymer chain substantially increases the rate of scission of the polymer under tension (≥2.6× faster) in solution, because deformation of the polymer backbone induced by the tightening knot activates otherwise unreactive covalent bonds. The fragments formed upon severing of the knotted chain differ from those that arise from cleavage of a similar, but unknotted, polymer. Our solution studies provide experimental evidence that knotting can contribute to higher mechanical scission rates of polymers. It also demonstrates that entanglement design can be used to generate mechanophores that are among the most reactive described to date, providing opportunities to increase the reactivity of otherwise inert functional groups.
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Affiliation(s)
- Min Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Robert Nixon
- Department of Chemistry, University of Manchester, Manchester, UK
| | | | - Lucian Pirvu
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Manchester, UK.
| | - David A Leigh
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
- Department of Chemistry, University of Manchester, Manchester, UK.
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2
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Abstract
Force-controlled release of small molecules offers great promise for the delivery of drugs and the release of healing or reporting agents in a medical or materials context1-3. In polymer mechanochemistry, polymers are used as actuators to stretch mechanosensitive molecules (mechanophores)4. This technique has enabled the release of molecular cargo by rearrangement, as a direct5,6 or indirect7-10 consequence of bond scission in a mechanophore, or by dissociation of cage11, supramolecular12 or metal complexes13,14, and even by 'flex activation'15,16. However, the systems described so far are limited in the diversity and/or quantity of the molecules released per stretching event1,2. This is due to the difficulty in iteratively activating scissile mechanophores, as the actuating polymers will dissociate after the first activation. Physical encapsulation strategies can be used to deliver a larger cargo load, but these are often subject to non-specific (that is, non-mechanical) release3. Here we show that a rotaxane (an interlocked molecule in which a macrocycle is trapped on a stoppered axle) acts as an efficient actuator to trigger the release of cargo molecules appended to its axle. The release of up to five cargo molecules per rotaxane actuator was demonstrated in solution, by ultrasonication, and in bulk, by compression, achieving a release efficiency of up to 71% and 30%, respectively, which places this rotaxane device among the most efficient release systems achieved so far1. We also demonstrate the release of three representative functional molecules (a drug, a fluorescent tag and an organocatalyst), and we anticipate that a large variety of cargo molecules could be released with this device. This rotaxane actuator provides a versatile platform for various force-controlled release applications.
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Affiliation(s)
- Lei Chen
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Robert Nixon
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Manchester, UK.
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3
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Abstract
Mechanophores (mechanosensitive molecules) have been instrumental in the development of various force-controlled release systems. However, the release of functional organic molecules is often the consequence of a secondary (nonmechanical) process triggered by an initial bond scission. Here we present a new mechanophore, built around an oxanorbornane-triazoline core, that is able to release a furan molecule following a force-promoted double retro-[4+2][3+2] cycloaddition. We explored this unprecedented transformation experimentally (sonication) and computationally (DFT, CoGEF) and found that the observed reactivity is controlled by the geometry of the adduct, as this reaction pathway is only accessible to the endo-exo-cis isomer. These results further demonstrate the unique reactivity of molecules under tension and offer a new mechanism for the force-controlled release of small molecules.
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Affiliation(s)
- Kamil Suwada
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Alice Weng Ieong
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Hei Lok Herman Lo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
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4
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Cardosa-Gutierrez M, De Bo G, Duwez AS, Remacle F. Correction: Bond breaking of furan-maleimide adducts via a diradical sequential mechanism under an external mechanical force. Chem Sci 2023; 14:2467. [PMID: 36873843 PMCID: PMC9977428 DOI: 10.1039/d3sc90024j] [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: 01/30/2023] [Accepted: 01/30/2023] [Indexed: 02/17/2023] Open
Abstract
[This corrects the article DOI: 10.1039/D2SC05051J.].
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Affiliation(s)
| | - Guillaume De Bo
- Department of Chemistry, University of ManchesterManchesterM13 9PLUK
| | - Anne-Sophie Duwez
- UR Molecular Systems, Department of Chemistry, University of Liège 4000 Liège Belgium
| | - Francoise Remacle
- UR Molecular Systems, Department of Chemistry, University of Liège 4000 Liège Belgium
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5
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Cardosa-Gutierrez M, De Bo G, Duwez AS, Remacle F. Bond breaking of furan-maleimide adducts via a diradical sequential mechanism under an external mechanical force. Chem Sci 2023; 14:1263-1271. [PMID: 36756317 PMCID: PMC9891376 DOI: 10.1039/d2sc05051j] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 12/27/2022] [Indexed: 01/06/2023] Open
Abstract
Substituted furan-maleimide Diels-Alder adducts are bound by dynamic covalent bonds that make them particularly attractive mechanophores. Thermally activated [4 + 2] retro-Diels-Alder (DA) reactions predominantly proceed via a concerted mechanism in the ground electronic state. We show that an asymmetric mechanical force along the anchoring bonds in both the endo and exo isomers of proximal dimethyl furan-maleimide adducts favors a sequential pathway. The switching from a concerted to a sequential mechanism occurs at external forces of ≈1 nN. The first bond rupture occurs for a projection of the pulling force on the scissile bond at ≈4.3 nN for the exo adduct and ≈3.8 nN for the endo one. The reaction is inhibited for external forces up to ≈3.4 nN for the endo adduct and 3.6 nN for the exo one after which it is activated. In the activated region, at 4 nN, the rupture rate of the first bond for the endo adduct is computed to be ≈3 orders of magnitude larger than for the exo one in qualitative agreement with recent sonication experiments [Z. Wang and S. L. Craig, Chem. Commun., 2019, 55, 12263-12266]. In the intermediate region of the path between the rupture of the first and the second bond, the lowest singlet state exhibits a diradical character for both adducts and is close in energy to a diradical triplet state. The computed values of spin-orbit coupling along the path are too small for inducing intersystem crossings. These findings open the way for the rational design of DA mechanophores for polymer science and photochemistry.
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Affiliation(s)
| | - Guillaume De Bo
- Department of Chemistry, University of ManchesterManchesterM13 9PLUK
| | - Anne-Sophie Duwez
- UR Molecular Systems, Department of Chemistry, University of Liège 4000 Liège Belgium
| | - Francoise Remacle
- UR Molecular Systems, Department of Chemistry, University of Liège 4000 Liège Belgium
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6
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Janpatompong Y, Suwada K, Turner ML, De Bo G. Mechanical stability of cis, trans - poly(p-phenylene vinylenes). Polym Chem 2023. [DOI: 10.1039/d3py00021d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Understanding the stability of conjugated polymers towards mechanical stimuli is critical for optimizing the processing and use of these materials in a range of electronic and optoelectronic devices, such as...
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7
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Wu M, Li Y, Yuan W, De Bo G, Cao Y, Chen Y. Cooperative and Geometry-Dependent Mechanochromic Reactivity through Aromatic Fusion of Two Rhodamines in Polymers. J Am Chem Soc 2022; 144:17120-17128. [PMID: 36070612 DOI: 10.1021/jacs.2c07015] [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: 11/29/2022]
Abstract
The unique topological features of Piezo proteins underlie the lever-like cellular mechanotransduction mechanism. This knowledge inspires us to seek topological/geometric control of mechanochromophores with unprecedentedly amplified, synergistic changes in polymers to serve as ideal stress probes. Here, by judicious placement of two spirolactam rings into aminobenzopyranoxanthene, a series of stereo- and regio-isomeric rhodamine-like mechanophores are developed. With two labile bonds closely coupled into one rigidified scaffold, these π-fused bis-mechanophores enable mechanochromic polymers, featuring cooperative bond scission, low rupture force (lower than rhodamine), and geometry-controlled ring-opening reactivity. Sonication, single-molecule force spectroscopy experiments, and density functional theory calculations provide insight into the force-color relationship and rationalize how the difference in reactivity of the four isomeric mechanophores is affected by their molecular geometry and thermodynamic equilibrium. Our strategy based on the aromatic fusion of bis-mechanophore promises a modular approach to isomeric mechanophores for cooperative bond scission. Also, important insights into internal and external factors governing tandem mechanochemical reactions are gained.
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Affiliation(s)
- Mengjiao Wu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, P. R. China.,Department of Chemistry, Tianjin University, Tianjin 300354, P. R. China
| | - Yiran Li
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, P. R. China
| | - Wei Yuan
- Department of Chemistry, Tianjin University, Tianjin 300354, P. R. China
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Yi Cao
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, P. R. China
| | - Yulan Chen
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, P. R. China
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8
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Abstract
In polymer mechanochemistry, mechanosensitive molecules (mechanophores) are activated upon elongation of anchored polymer arms. The reactivity of a mechanophore can be influenced by a variety of structural factors, including the geometry of attachment of the polymer arms and the nature of eventual substituents. Here we investigate stereoelectronic effects in force-accelerated Diels–Alder reactions using the CoGEF (Constrained Geometries simulate External Force) calculation method. We found that the presence of an electron-donating heteroatom on the diene leads to a lower activation force, and that the mechanochemical reactivity is suppressed when the anchor group is attached to a central rather than lateral position.
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Affiliation(s)
- Lik Chun Wu
- Department of Chemistry, The University of Manchester, Manchester, United Kingdom of Great Britain and Northern Ireland
| | - Guillaume De Bo
- Department of Chemistry, The University of Manchester, Manchester, United Kingdom of Great Britain and Northern Ireland
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9
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Abstract
In mechanochemistry, molecules under tension can react in unexpected ways. The reactivity of mechanophores (mechanosensitive molecules) can be controlled using various geometric or electronic factors. Often these factors affect the rate of mechanical activation but sometimes give rise to alternative reaction pathways. Here we show that a simple isotope substitution (H to D) leads to a reversal of selectivity in the activation of a mechanophore. Remarkably this isotope effect is not kinetic in nature but emerges from dynamic effects in which deuteration reduces the ability of the reactant to follow a post-transition-state concerted trajectory on the bifurcated force-modified potential energy surface. These results give a new insight into the reactivity of molecules under tension.
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Affiliation(s)
- Robert Nixon
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
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10
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Abstract
Tensile forces influence a variety of important biological processes and force sensors are required to study these processes in vivo. Current force sensors are often tailor-made for a specific application, or activate at much higher forces than those observed at the cellular or tissue level. A versatile force sensor, with tunable mechanical and optical properties, activated at low pN forces will be ideal. In this communication, a new mechanoresponsive fluorescent hydrogen-bonded rotaxane, built around a maleimide dye, is reported. Its force-sensing properties are demonstrated in a polyacrylamide gel, a synthetic model of living tissue.
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Affiliation(s)
| | - ThomasR Carr
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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11
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Affiliation(s)
- Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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12
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13
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Abstract
Mechanophores (mechanoresponsive molecules) offer great promises for the development of smart force-responsive materials. The activity of a mechanophore can be tuned by altering its structure or the composition of the actuating polymer. Here we show that a [2]catenane can act as a mechanical protecting group by diverting tensional forces away from a mechanically active functional group embedded in one of its rings. This property emerges from the mobility of the two rings of the catenane, which are able to rotate along each other until the tension equalizes over the entirety of the catenated framework. This approach provides a new way to control the mechanical activity of a mechanophore.
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Affiliation(s)
- Min Zhang
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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14
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Abstract
Increasingly complex rotaxane-based molecular devices are interfaced with polymers and surfaces, but suitable bifunctional stoppering groups are lacking. Here, we report a two-step, high-yielding synthesis toward a new class of heterobifunctional triarylmethane stoppers. They possess hydroxyl and ester groups for further functionalization as well as halogen substituents conferring a diagnostic spectroscopic signature. Their utility was demonstrated with the synthesis of a chain-centered macromolecular rotaxane. This new stopper architecture should prove useful to connect rotaxanes with polymers and surfaces for applications in polymer mechanochemistry, single-molecule force spectroscopy, smart materials, and molecular machines.
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Affiliation(s)
- Min Zhang
- Department of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom
| | - Olga Shvetsova
- Department of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom
| | - Guillaume De Bo
- Department of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom
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15
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Abstract
Polymers containing two adjacent mechanophores cleave at the same as a single-mechanophore chains.
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Affiliation(s)
| | - Min Zhang
- Department of Chemistry
- University of Manchester
- Manchester M13 9PL
- UK
| | - Guillaume De Bo
- Department of Chemistry
- University of Manchester
- Manchester M13 9PL
- UK
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16
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Affiliation(s)
- Min Zhang
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Guillaume De Bo
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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17
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Affiliation(s)
- Min Zhang
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Guillaume De Bo
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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18
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De Bo G, Kitchen JA, Serpell CJ. Emerging investigators in the UK – editorial. Supramol Chem 2018. [DOI: 10.1080/10610278.2018.1475606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Guillaume De Bo
- School of Chemistry, University of Manchester , Manchester UK
| | - Jonathan A. Kitchen
- Chemistry, Institute of Natural and Mathematical Sciences, Massey university , Auckland New Zealand
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19
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De Bo G, Gall MAY, Kuschel S, De Winter J, Gerbaux P, Leigh DA. An artificial molecular machine that builds an asymmetric catalyst. Nat Nanotechnol 2018; 13:381-385. [PMID: 29610529 DOI: 10.1038/s41565-018-0105-3] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Accepted: 02/23/2018] [Indexed: 05/29/2023]
Abstract
Biomolecular machines perform types of complex molecular-level tasks that artificial molecular machines can aspire to. The ribosome, for example, translates information from the polymer track it traverses (messenger RNA) to the new polymer it constructs (a polypeptide) 1 . The sequence and number of codons read determines the sequence and number of building blocks incorporated into the biomachine-synthesized polymer. However, neither control of sequence2,3 nor the transfer of length information from one polymer to another (which to date has only been accomplished in man-made systems through template synthesis) 4 is easily achieved in the synthesis of artificial macromolecules. Rotaxane-based molecular machines5-7 have been developed that successively add amino acids8-10 (including β-amino acids 10 ) to a growing peptide chain by the action of a macrocycle moving along a mono-dispersed oligomeric track derivatized with amino-acid phenol esters. The threaded macrocycle picks up groups that block its path and links them through successive native chemical ligation reactions 11 to form a peptide sequence corresponding to the order of the building blocks on the track. Here, we show that as an alternative to translating sequence information, a rotaxane molecular machine can transfer the narrow polydispersity of a leucine-ester-derivatized polystyrene chain synthesized by atom transfer radical polymerization 12 to a molecular-machine-made homo-leucine oligomer. The resulting narrow-molecular-weight oligomer folds to an α-helical secondary structure 13 that acts as an asymmetric catalyst for the Juliá-Colonna epoxidation14,15 of chalcones.
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Affiliation(s)
- Guillaume De Bo
- School of Chemistry, University of Manchester, Manchester, UK
| | | | - Sonja Kuschel
- School of Chemistry, University of Manchester, Manchester, UK
| | - Julien De Winter
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, Mons, Belgium
| | - Pascal Gerbaux
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, Mons, Belgium
| | - David A Leigh
- School of Chemistry, University of Manchester, Manchester, UK.
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Abstract
Strong and stable under tension?
Strong and stable under tension? In this review we present the recent efforts investigating the mechanochemical properties of interlocked structures by atomic force microscopy and polymer mechanochemistry.
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Affiliation(s)
- Guillaume De Bo
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
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21
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Affiliation(s)
- Richard Stevenson
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Guillaume De Bo
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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De Bo G, Leigh DA, McTernan CT, Wang S. A complementary pair of enantioselective switchable organocatalysts. Chem Sci 2017; 8:7077-7081. [PMID: 29147536 PMCID: PMC5637462 DOI: 10.1039/c7sc02462b] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [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: 06/01/2017] [Accepted: 08/22/2017] [Indexed: 12/11/2022] Open
Abstract
A pair of enantioselective switchable bifunctional catalysts are shown to promote a range of conjugate addition reactions in up to 95 : 5 e.r. and 95% conversion. Each catalyst can be switched OFF using conditions that switch the other catalyst ON. Catalyst ON : OFF ratios of up to 98 : 2 and 1 : 99 were achieved, with a ratio of reaction rates of up to 16 : 1 between the ON and OFF states, maintained over complete ON-OFF-ON and OFF-ON-OFF cycles. However, simultaneous operation of the catalyst pair in the same reaction vessel, which in principle could allow product handedness to be switched by simple E-Z isomerisation of the catalyst pair, was unsuccessful. In this first generation complementary pair of enantioselective switchable organocatalysts, the OFF state of one catalyst inhibits the ON state of the other.
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Affiliation(s)
- Guillaume De Bo
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
| | - David A Leigh
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
| | - Charlie T McTernan
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
| | - Shoufeng Wang
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
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De Bo G, Gall MAY, Kitching MO, Kuschel S, Leigh DA, Tetlow DJ, Ward JW. Sequence-Specific β-Peptide Synthesis by a Rotaxane-Based Molecular Machine. J Am Chem Soc 2017; 139:10875-10879. [DOI: 10.1021/jacs.7b05850] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Guillaume De Bo
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Malcolm A. Y. Gall
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Matthew O. Kitching
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Sonja Kuschel
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - David A. Leigh
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Daniel J. Tetlow
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - John W. Ward
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
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24
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Affiliation(s)
- Guillaume De Bo
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Guillaume Dolphijn
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Charlie T. McTernan
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - David A. Leigh
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
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Beswick J, Blanco V, De Bo G, Leigh DA, Lewandowska U, Lewandowski B, Mishiro K. Selecting reactions and reactants using a switchable rotaxane organocatalyst with two different active sites. Chem Sci 2014; 6:140-143. [PMID: 28553462 PMCID: PMC5424444 DOI: 10.1039/c4sc03279a] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [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: 10/26/2014] [Accepted: 11/13/2014] [Indexed: 11/21/2022] Open
Abstract
The activation mode of a rotaxane-based organocatalyst with both secondary amine and squaramide catalytic units can be switched with acid or base. The macrocycle blocks whichever of the catalytic sites it is positioned over. The switchable rotaxane catalyst generates different products from a mixture of three building blocks according to the location of the macrocyclic ring in the rotaxane.
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Affiliation(s)
- Jack Beswick
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK . ; http://www.catenane.net
| | - Victor Blanco
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK . ; http://www.catenane.net
| | - Guillaume De Bo
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK . ; http://www.catenane.net
| | - David A Leigh
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK . ; http://www.catenane.net
| | - Urszula Lewandowska
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK . ; http://www.catenane.net
| | - Bartosz Lewandowski
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK . ; http://www.catenane.net
| | - Kenji Mishiro
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK . ; http://www.catenane.net
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De Bo G, Kuschel S, Leigh DA, Lewandowski B, Papmeyer M, Ward JW. Efficient assembly of threaded molecular machines for sequence-specific synthesis. J Am Chem Soc 2014; 136:5811-4. [PMID: 24678971 DOI: 10.1021/ja5022415] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We report on an improved strategy for the preparation of artificial molecular machines that can pick up and assemble reactive groups in sequence by traveling along a track. In the new approach a preformed rotaxane synthon is attached to the end of an otherwise fully formed strand of building blocks. This "rotaxane-capping" protocol is significantly more efficient than the "final-step-threading" method employed previously and enables the synthesis of threaded molecular machines that operate on extended oligomer, and potentially polymer, tracks. The methodology is exemplified through the preparation of a machine that adds four amino acid building blocks from a strand in sequence, featuring up to 20-membered ring native chemical ligation transition states.
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Affiliation(s)
- Guillaume De Bo
- School of Chemistry, University of Manchester , Oxford Road, Manchester, M13 9PL United Kingdom
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27
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De Bo G, Leigh DA. [A molecular machine mimicking the ribosome: a molecule that makes molecules]. Med Sci (Paris) 2013; 29:452-4. [PMID: 23732089 DOI: 10.1051/medsci/2013295003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Guillaume De Bo
- University of Manchester, school of chemistry, Oxford road, M13 9PL, Manchester, Royaume Uni.
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Lewandowski B, De Bo G, Ward JW, Papmeyer M, Kuschel S, Aldegunde MJ, Gramlich PME, Heckmann D, Goldup SM, D'Souza DM, Fernandes AE, Leigh DA. Sequence-specific peptide synthesis by an artificial small-molecule machine. Science 2013; 339:189-93. [PMID: 23307739 DOI: 10.1126/science.1229753] [Citation(s) in RCA: 551] [Impact Index Per Article: 50.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The ribosome builds proteins by joining together amino acids in an order determined by messenger RNA. Here, we report on the design, synthesis, and operation of an artificial small-molecule machine that travels along a molecular strand, picking up amino acids that block its path, to synthesize a peptide in a sequence-specific manner. The chemical structure is based on a rotaxane, a molecular ring threaded onto a molecular axle. The ring carries a thiolate group that iteratively removes amino acids in order from the strand and transfers them to a peptide-elongation site through native chemical ligation. The synthesis is demonstrated with ~10(18) molecular machines acting in parallel; this process generates milligram quantities of a peptide with a single sequence confirmed by tandem mass spectrometry.
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Affiliation(s)
- Bartosz Lewandowski
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
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De Bo G, Markó IE. Studies towards the Synthesis of Pentalenene: Mechanistic Insights into the Isomerization Phenomenon During RCM of Medium-Sized Rings. European J Org Chem 2011. [DOI: 10.1002/ejoc.201001475] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Berthon-Gelloz G, Schumers JM, De Bo G, Markó IE. Highly β-(E)-Selective Hydrosilylation of Terminal and Internal Alkynes Catalyzed by a (IPr)Pt(diene) Complex. J Org Chem 2008; 73:4190-7. [DOI: 10.1021/jo800411e] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Guillaume Berthon-Gelloz
- Université catholique de Louvain, Département de Chimie, Place Louis Pasteur, 1348 Louvain-la-Neuve, Belgium
| | - Jean-Marc Schumers
- Université catholique de Louvain, Département de Chimie, Place Louis Pasteur, 1348 Louvain-la-Neuve, Belgium
| | - Guillaume De Bo
- Université catholique de Louvain, Département de Chimie, Place Louis Pasteur, 1348 Louvain-la-Neuve, Belgium
| | - István E. Markó
- Université catholique de Louvain, Département de Chimie, Place Louis Pasteur, 1348 Louvain-la-Neuve, Belgium
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Affiliation(s)
- Guillaume De Bo
- Département de Chimie, Université Catholique de Louvain, Place Louis Pasteur, 1, 1348 Louvain-la-Neuve, Belgium
| | - Guillaume Berthon-Gelloz
- Département de Chimie, Université Catholique de Louvain, Place Louis Pasteur, 1, 1348 Louvain-la-Neuve, Belgium
| | - Bernard Tinant
- Département de Chimie, Université Catholique de Louvain, Place Louis Pasteur, 1, 1348 Louvain-la-Neuve, Belgium
| | - István E. Markó
- Département de Chimie, Université Catholique de Louvain, Place Louis Pasteur, 1, 1348 Louvain-la-Neuve, Belgium
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