1
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Doerner B, Della Sala F, Wang S, Webb SJ. Reaction, Recognition, Relay: Anhydride Hydrolysis Reported by Conformationally Responsive Fluorinated Foldamers in Micelles. Angew Chem Int Ed Engl 2024; 63:e202405924. [PMID: 38703400 DOI: 10.1002/anie.202405924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 04/23/2024] [Accepted: 04/29/2024] [Indexed: 05/06/2024]
Abstract
Natural membrane receptors are proteins that can report on changes in the concentration of external chemical messengers. Messenger binding to a receptor produces conformational changes that are relayed through the membrane into the cell; this information allows cells to adapt to changes in their environment. Artificial membrane receptors (R)-1 and (S)-1 are helical α-aminoisobutyric acid (Aib) foldamers that replicate key parts of this information relay. Solution-phase 19F NMR spectroscopy of zinc(II)-capped receptor 1, either in organic solvent or in membrane-mimetic micelles, showed messenger binding produced an enrichment of either left- or right-handed screw-sense; the chirality of the bound messenger was relayed to the other receptor terminus. Furthermore, in situ production of a chemical messenger in the external aqueous environment could be detected in real-time by a racemic mixture of receptor 1 in micelles. The hydrolysis of insoluble anhydrides produced carboxylate in the aqueous phase, which bound to the receptors and gave a distinct 19F NMR output from inside the hydrophobic region of the micelles.
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Affiliation(s)
- Benedicte Doerner
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Flavio Della Sala
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Siyuan Wang
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Simon J Webb
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
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2
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Chen Z, Tan M, Shan C, Yuan X, Chen L, Shi J, Lan Y, Li Y. Aryne 1,4‐Disubstitution and Remote Diastereoselective 1,2,4‐Trisubstitution via a Nucleophilic Annulation‐[5,5]‐Sigmatropic Rearrangement Process. Angew Chem Int Ed Engl 2022; 61:e202212160. [DOI: 10.1002/anie.202212160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Zhonghong Chen
- College of Chemistry Jilin University Changchun 130012 P. R. China
- School of Chemistry and Chemical Engineering Chongqing University 174 Shazheng St. Chongqing 400030 P. R. China
| | - Min Tan
- School of Chemistry and Chemical Engineering Chongqing University 174 Shazheng St. Chongqing 400030 P. R. China
| | - Chunhui Shan
- School of Chemistry and Chemical Engineering Chongqing University 174 Shazheng St. Chongqing 400030 P. R. China
- College of Chemistry Chongqing Normal University Chongqing 401331 P. R. China
| | - Xiaoling Yuan
- School of Chemistry and Chemical Engineering Chongqing University 174 Shazheng St. Chongqing 400030 P. R. China
| | - Liyuan Chen
- School of Chemistry and Chemical Engineering Chongqing University 174 Shazheng St. Chongqing 400030 P. R. China
| | - Jiarong Shi
- School of Chemistry and Chemical Engineering Chongqing University 174 Shazheng St. Chongqing 400030 P. R. China
| | - Yu Lan
- School of Chemistry and Chemical Engineering Chongqing University 174 Shazheng St. Chongqing 400030 P. R. China
- Green Catalysis Center and College of Chemistry Zhengzhou University Zhengzhou Henan, 450001 P. R. China
| | - Yang Li
- College of Chemistry Jilin University Changchun 130012 P. R. China
- School of Chemistry and Chemical Engineering Chongqing University 174 Shazheng St. Chongqing 400030 P. R. China
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3
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Ma C, Tang J, Yu L, Wen K, Gan Q. Optimization of an Asymmetric Reaction in the Cavity of Chiral Aromatic Oligoamide Foldamers. Chemistry 2022; 28:e202200834. [DOI: 10.1002/chem.202200834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Chunmiao Ma
- Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Jie Tang
- Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Lu Yu
- Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Kehan Wen
- Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Quan Gan
- Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
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4
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Tilly DP, Cullen W, Zhong H, Jamagne R, Vitórica-Yrezábal I, Webb SJ. α-Amino-iso-butyric acid foldamers terminated with rhodium(I) N-heterocyclic carbene catalysts. Chemistry 2021; 28:e202104293. [PMID: 34932229 PMCID: PMC9305545 DOI: 10.1002/chem.202104293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Indexed: 12/01/2022]
Abstract
To investigate how remotely induced changes in ligand folding might affect catalysis by organometallic complexes, dynamic α‐amino‐iso‐butyric acid (Aib) peptide foldamers bearing rhodium(I) N‐heterocyclic carbene (NHC) complexes have been synthesized and studied. X‐ray crystallography of a foldamer with an N‐terminal azide and a C‐terminal Rh(NHC)(Cl)(diene) complex showed a racemate with a chiral axis in the Rh(NHC) complex and a distorted 310 helical body. Replacing the azide with either one or two chiral L‐α‐methylvaline (L‐αMeVal) residues gave diastereoisomeric foldamers that each possessed point, helical and axial chirality. NMR spectroscopy revealed an unequal ratio of diastereoisomers for some foldamers, indicating that the chiral conformational preference of the N‐terminal residue(s) was relayed down the 1 nm helical body to the axially chiral Rh(NHC) complex. Although the remote chiral residue(s) did not affect the stereoselectivity of hydrosilylation reactions catalysed by these foldamers, these studies suggest a potential pathway towards remote conformational control of organometallic catalysts.
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Affiliation(s)
- David P Tilly
- The University of Manchester, Department of Chemistry, UNITED KINGDOM
| | - William Cullen
- The University of Manchester, Department of Chemistry, UNITED KINGDOM
| | - Heng Zhong
- The University of Manchester, Department of Chemistry, UNITED KINGDOM
| | - Romain Jamagne
- The University of Manchester, Department of Chemistry, UNITED KINGDOM
| | | | - Simon John Webb
- University of Manchester, School of Chemistry and MIB, 131 Princess St, M1 7DN, Manchester, UNITED KINGDOM
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5
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Bodero L, Guitot K, Lensen N, Lequin O, Brigaud T, Ongeri S, Chaume G. Introducing the Chiral Constrained α-Trifluoromethylalanine in Aib foldamers to Control, Quantify and Assign the Helical Screw-Sense. Chemistry 2021; 28:e202103887. [PMID: 34890083 DOI: 10.1002/chem.202103887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Indexed: 11/11/2022]
Abstract
Oligomers of α-aminoisobutyric acid (Aib) are achiral peptides that adopt 3 10 helical structures with equal population of left- and right-handed conformers. Yet, the screw-sense preference of the helical chain may be controlled by a single chiral residue located at one terminus. 1 H and 19 F NMR, X-ray crystallography and circular dichroism studies on new Aib oligomers show that the incorporation of a chiral quaternary α-trifluoromethylalanine at their N -terminus induces a reversal of the screw-sense preference of the 3 10 -helix compared to that of a non-fluorinated analogue having an l-α-methyl valine residue. This work demonstrates that, among the many particular properties of introducing a trifluoromethyl group into foldamers, its stereo-electronic properties are of major interest to control the helical screw sense. Its use as an easy-to-handle 19 F NMR probe to reliably determine both the magnitude of the screw-sense preference and its sign assignment is also of remarkable interest.
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Affiliation(s)
| | | | | | - Olivier Lequin
- Sorbonne Université Campus Pierre et Marie Curie: Sorbonne Universite Campus Pierre et Marie Curie, chemistry, FRANCE
| | | | | | - Grégory Chaume
- CY Cergy Paris Universite, Chemistry, 5 mail Gay Lussac, 95000, Cergy-Pontoise, FRANCE
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6
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Rodríguez R, Suárez‐Picado E, Quiñoá E, Riguera R, Freire F. A Stimuli‐Responsive Macromolecular Gear: Interlocking Dynamic Helical Polymers with Foldamers. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915488] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Rafael Rodríguez
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
| | - Esteban Suárez‐Picado
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
| | - Emilio Quiñoá
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
| | - Ricardo Riguera
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
| | - Félix Freire
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
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7
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Rodríguez R, Suárez‐Picado E, Quiñoá E, Riguera R, Freire F. A Stimuli‐Responsive Macromolecular Gear: Interlocking Dynamic Helical Polymers with Foldamers. Angew Chem Int Ed Engl 2020; 59:8616-8622. [DOI: 10.1002/anie.201915488] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 02/07/2020] [Indexed: 01/11/2023]
Affiliation(s)
- Rafael Rodríguez
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
| | - Esteban Suárez‐Picado
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
| | - Emilio Quiñoá
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
| | - Ricardo Riguera
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
| | - Félix Freire
- Centro Singular de investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
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8
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Baráth E, Mejía E. Ein Fest der Wissenschaft inmitten der Natur: Die 54. Bürgenstock‐Konferenz. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201906781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Eszter Baráth
- Department ChemieZentralforschungsinstitut für KatalyseTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
| | - Esteban Mejía
- Leibniz-Institut für Katalyse (LIKAT) Albert-Einstein-Straße 29a 18059 Rostock Deutschland
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9
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Baráth E, Mejía E. A Celebration of Science amidst Nature: The 54th Bürgenstock Conference. Angew Chem Int Ed Engl 2019; 58:17107-17113. [PMID: 31441577 DOI: 10.1002/anie.201906781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Indexed: 11/11/2022]
Affiliation(s)
- Eszter Baráth
- Department of Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748, Garching, Germany
| | - Esteban Mejía
- Leibniz Institute for Catalysis (LIKAT), Albert-Einstein-Straße 29a, 18059, Rostock, Germany
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10
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Bravin C, Mason G, Licini G, Zonta C. A Diastereodynamic Probe Transducing Molecular Length into Chiroptical Readout. J Am Chem Soc 2019; 141:11963-11969. [DOI: 10.1021/jacs.9b04151] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Carlo Bravin
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, 35131 Padova, Italy
| | - Giulia Mason
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, 35131 Padova, Italy
| | - Giulia Licini
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, 35131 Padova, Italy
| | - Cristiano Zonta
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, 35131 Padova, Italy
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11
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Urushima A, Ousaka N, Yashima E. Tug-of-War in a Dynamic Helical Peptide: Solvent-Induced Helix-Helix Transition of a Lactam-Bridged Peptide Composed of Point- and Axial Chiralities Remote from Each Other. Chem Asian J 2018; 13:3150-3154. [DOI: 10.1002/asia.201801111] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Akio Urushima
- Department of Molecular and Macromolecular Chemistry; Graduate School of Engineering; Nagoya University; Chikusa-ku Nagoya 464-8603 Japan
| | - Naoki Ousaka
- Department of Molecular and Macromolecular Chemistry; Graduate School of Engineering; Nagoya University; Chikusa-ku Nagoya 464-8603 Japan
| | - Eiji Yashima
- Department of Molecular and Macromolecular Chemistry; Graduate School of Engineering; Nagoya University; Chikusa-ku Nagoya 464-8603 Japan
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12
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Greenfield JL, Evans EW, Di Nuzzo D, Di Antonio M, Friend RH, Nitschke JR. Unraveling Mechanisms of Chiral Induction in Double-Helical Metallopolymers. J Am Chem Soc 2018; 140:10344-10353. [PMID: 30024156 PMCID: PMC6114842 DOI: 10.1021/jacs.8b06195] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Indexed: 12/18/2022]
Abstract
Self-assembled helical polymers hold great promise as new functional materials, where helical handedness controls useful properties such as circularly polarized light emission or electron spin. The technique of subcomponent self-assembly can generate helical polymers from readily prepared monomers. Here we present three distinct strategies for chiral induction in double-helical metallopolymers prepared via subcomponent self-assembly: (1) employing an enantiopure monomer, (2) polymerization in a chiral solvent, (3) using an enantiopure initiating group. Kinetic and thermodynamic models were developed to describe the polymer growth mechanisms and quantify the strength of chiral induction, respectively. We found the degree of chiral induction to vary as a function of polymer length. Ordered, rod-like aggregates more than 70 nm long were also observed in the solid state. Our findings provide a basis to choose the most suitable method of chiral induction based on length, regiochemical, and stereochemical requirements, allowing stereochemical control to be established in easily accessible ways.
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Affiliation(s)
- Jake L. Greenfield
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United
Kingdom
| | - Emrys W. Evans
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, United Kingdom
| | - Daniele Di Nuzzo
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, United Kingdom
| | - Marco Di Antonio
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United
Kingdom
| | - Richard H. Friend
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, United Kingdom
| | - Jonathan R. Nitschke
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United
Kingdom
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13
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Lizio MG, Andrushchenko V, Pike SJ, Peters AD, Whitehead GFS, Vitórica-Yrezábal IJ, Mutter ST, Clayden J, Bouř P, Blanch EW, Webb SJ. Optically Active Vibrational Spectroscopy of α-Aminoisobutyric Acid Foldamers in Organic Solvents and Phospholipid Bilayers. Chemistry 2018; 24:9399-9408. [PMID: 29745985 DOI: 10.1002/chem.201801121] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Indexed: 12/12/2022]
Abstract
Helical α-aminoisobutyric acid (Aib) foldamers show great potential as devices for the communication of conformational information across phospholipid bilayers, but determining their conformation in bilayers remains a challenge. In the present study, Raman, Raman optical activity (ROA), infrared (IR) and vibrational circular dichroism (VCD) spectroscopies have been used to analyze the conformational preferences of Aib foldamers in solution and when interacting with bilayers. A 310 -helix marker band at 1665-1668 cm-1 in Raman spectra was used to show that net helical content increased strongly with oligomer length. ROA and VCD spectra of chiral Aib foldamers provided the chiroptical signature for both left- and right-handed 310 -helices in organic solvents, with VCD establishing that foldamer screw-sense was preserved when the foldamers became embedded within bilayers. However, the population distribution between different secondary structures was perturbed by the chiral phospholipid. These studies indicate that ROA and VCD spectroscopies are valuable tools for the study of biomimetic structures, such as artificial signal transduction molecules, in phospholipid bilayers.
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Affiliation(s)
- Maria Giovanna Lizio
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess St, Manchester, M1 7DN, UK.,School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Valery Andrushchenko
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Sarah J Pike
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess St, Manchester, M1 7DN, UK.,School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.,Faculty of Life Sciences, University of Bradford, Bradford, West Yorkshire, BD7 1DP, UK
| | - Anna D Peters
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess St, Manchester, M1 7DN, UK.,School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - George F S Whitehead
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | | | - Shaun T Mutter
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess St, Manchester, M1 7DN, UK
| | - Jonathan Clayden
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Petr Bouř
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Ewan W Blanch
- School of Science, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - Simon J Webb
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess St, Manchester, M1 7DN, UK.,School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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14
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Baskin M, Maayan G. Chiral Cu(ii), Co(ii) and Ni(ii) complexes based on 2,2′-bipyridine modified peptoids. Dalton Trans 2018; 47:10767-10774. [DOI: 10.1039/c8dt01308j] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Helical peptoids bearing 2,2′-bipyridine, varied in their chiral bulky side chains and their N-terminus form chiral complexes with Cu(ii), Co(ii) and Ni(ii) via intramolecular binding.
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Affiliation(s)
- Maria Baskin
- Schulich Faculty of Chemistry
- Technion-Israel Institute of Technology
- Haifa
- Israel
| | - Galia Maayan
- Schulich Faculty of Chemistry
- Technion-Israel Institute of Technology
- Haifa
- Israel
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15
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Eto R, Oba M, Ueda A, Uku T, Doi M, Matsuo Y, Tanaka T, Demizu Y, Kurihara M, Tanaka M. Diastereomeric Right- and Left-Handed Helical Structures with Fourteen (R)-Chiral Centers. Chemistry 2017; 23:18120-18124. [PMID: 29134704 DOI: 10.1002/chem.201705306] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Indexed: 12/31/2022]
Abstract
The relationship between chiral centers and the helical-screw control of their peptides has already been reported, but it has yet to be elucidated in detail. A chiral four-membered ring α,α-disubstituted α-amino acid with a (R,R)-butane-2,3-diol acetal moiety at the γ-position, but no α-chiral carbon, was synthesized. X-ray crystallographic analysis unambiguously revealed that its homo-chiral heptapeptide formed right-handed (P) and left-handed (M) 310 -helical structures at a ratio of 1:1. They appeared to be enantiomeric at the peptide backbone, but diastereomeric with fourteen (R)-configuration chiral centers. Conformational analyses of homopeptides in solution also indicated that diastereomeric (P) and (M) helices existed at approximately equal amounts, with a slight preference toward right-handedness, and they quickly interchanged at room temperature. The circumstances of chiral centers are important for the control of their helical-screw direction.
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Affiliation(s)
- Ryo Eto
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8521, Japan
| | - Makoto Oba
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8521, Japan
| | - Atsushi Ueda
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8521, Japan
| | - Tsubasa Uku
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8521, Japan
| | - Mitsunobu Doi
- Osaka University of Pharmaceutical Sciences, Osaka, 569-1094, Japan
| | - Yosuke Matsuo
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8521, Japan
| | - Takashi Tanaka
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8521, Japan
| | - Yosuke Demizu
- National Institute of Health Sciences, Tokyo, 158-8501, Japan
| | - Masaaki Kurihara
- Graduate School of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, 324-8501, Japan
| | - Masakazu Tanaka
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8521, Japan
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16
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Misra R, Saseendran A, George G, Veeresh K, Raja KMP, Raghothama S, Hofmann HJ, Gopi HN. Structural Dimorphism of Achiral α,γ-Hybrid Peptide Foldamers: Coexistence of 12- and 15/17-Helices. Chemistry 2017; 23:3764-3772. [DOI: 10.1002/chem.201605753] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Indexed: 01/17/2023]
Affiliation(s)
- Rajkumar Misra
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune 411021 India
| | - Abhijith Saseendran
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune 411021 India
| | - Gijo George
- NMR Research Center; Indian Institute of Science; Bangalore 560012 India
| | - Kuruva Veeresh
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune 411021 India
| | - K. Muruga Poopathi Raja
- Department of Physical Chemistry; School of Chemistry; Madurai Kamaraj University; Madurai 625 021 India
| | | | - Hans-Jörg Hofmann
- Institute of Biochemistry; Faculty of Biosciences, Pharmacy and Psychology; Talstraße 33 04103 Leipzig Germany
| | - Hosahudya N. Gopi
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune 411021 India
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17
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Kawasaki T, Ishikawa Y, Minato Y, Otsuka T, Yonekubo S, Sato I, Shibata T, Matsumoto A, Soai K. Point-to-Point Ultra-Remote Asymmetric Control with Flexible Linker. Chemistry 2017; 23:282-285. [PMID: 27801951 DOI: 10.1002/chem.201605076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Indexed: 11/06/2022]
Abstract
An ultra-remote intramolecular (point-to-point) asymmetric control through 38 bonds (1,39-asymmetric induction) has been achieved by using the principle of direct supramolecular orientation of catalytic and reactive moieties in asymmetric autocatalysis. We found the highly stereoselective diisopropylzinc addition reaction using designed molecules possessing pyrimidine sites at each terminal of a conformationally flexible simple methylene chain.
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Affiliation(s)
- Tsuneomi Kawasaki
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Research Center for Chirality, Research Institute for Science and Technology (RIST), Tokyo University of Science, Japan.,Department of Materials Science and Engineering, University of Fukui, Bunkyo, Fukui, 910-8507, Japan
| | - Yasuyuki Ishikawa
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Yoshihiro Minato
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Takashi Otsuka
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Shigeru Yonekubo
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Itaru Sato
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Graduate School of Science and Engineering, Ibaraki University, Bunkyo, Ibaraki, 310-8512, Japan
| | - Takanori Shibata
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan
| | - Arimasa Matsumoto
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Research Center for Chirality, Research Institute for Science and Technology (RIST), Tokyo University of Science, Japan
| | - Kenso Soai
- Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Research Center for Chirality, Research Institute for Science and Technology (RIST), Tokyo University of Science, Japan
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18
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Chen Y, Zhao Z, Bian Z, Jin R, Kang C, Qiu X, Guo H, Du Z, Gao L. Hexagonal Lyotropic Liquid Crystal from Simple "Abiotic" Foldamers. ChemistryOpen 2016; 5:386-94. [PMID: 27547649 PMCID: PMC4981060 DOI: 10.1002/open.201600007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Indexed: 12/04/2022] Open
Abstract
The motivation of foldamer chemistry is to identify novel building blocks that have the potential to imitate natural species. Peptides and peptide mimetics can form stable helical conformations and further self-assemble into diverse aggregates in water, where it is difficult to isolate a single helix. In contrast, most "abiotic" foldamers may fold into helical structures in solution, but are difficult to assemble into tertiary ones. It remains a challenge to obtain "abiotic" species similar to peptides. In this paper, a novel foldamer scaffold, in which p-phenyleneethynylene units are linked by chiral carbon atoms, was designed and prepared. In very dilute solutions, these oligomers were random coils. The hexamer and octamers could form a hexagonal lyotropic liquid crystal (LC) in CH2Cl2 when the concentrations reached the critical values. The microscopic observations indicated that they could assemble into the nanofibers in the LC. Interestingly, after some LC phases were diluted at room temperature, the nanofibers could be preserved. The good stabilities of the assemblies are possibly attributed to a more compact backbone and more rigid side chains.
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Affiliation(s)
- Yu Chen
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
- University of Chinese Academy of SciencesBeijing100049P. R. China
| | - Zhiqiang Zhao
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
- University of Chinese Academy of SciencesBeijing100049P. R. China
| | - Zheng Bian
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Rizhe Jin
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Chuanqing Kang
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Xuepeng Qiu
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Haiquan Guo
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Zhijun Du
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Lianxun Gao
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
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19
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Verma A, Baishya B. Real-time bilinear rotation decoupling in absorptive mode J-spectroscopy: Detecting low-intensity metabolite peak close to high-intensity metabolite peak with convenience. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 266:51-58. [PMID: 27026651 DOI: 10.1016/j.jmr.2016.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 03/02/2016] [Accepted: 03/05/2016] [Indexed: 06/05/2023]
Abstract
"Pure shift" NMR spectra display singlet peak per chemical site. Thus, high resolution is offered at the cost of valuable J-coupling information. In the present work, real-time BIRD (BIlinear Rotation Decoupling) is applied to the absorptive-mode 2D J-spectroscopy to provide pure shift spectrum in the direct dimension and J-coupling information in the indirect dimension. Quite often in metabolomics, proton NMR spectra from complex bio-fluids display tremendous signal overlap. Although conventional J-spectroscopy in principle overcomes this problem by separating the multiplet information from chemical shift information, however, only magnitude mode of the experiment is practical, sacrificing much of the potential high resolution that could be achieved. Few J-spectroscopy methods have been reported so far that produce high-resolution pure shift spectrum along with J-coupling information for crowded spectral regions. In the present work, high-quality J-resolved spectrum from important metabolomic mixture such as tissue extract from rat cortex is demonstrated. Many low-intensity metabolite peaks which are obscured by the broad dispersive tails from high-intensity metabolite peaks in regular magnitude mode J-spectrum can be clearly identified in real-time BIRD J-resolved spectrum. The general practice of removing such spectral overlap is tedious and time-consuming as it involves repeated sample preparation to change the pH of the tissue extract sample and subsequent spectra recording.
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Affiliation(s)
- Ajay Verma
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow 226014, India
| | - Bikash Baishya
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow 226014, India.
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20
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Naganawa Y, Kawagishi M, Ito JI, Nishiyama H. Asymmetric Induction at Remote Quaternary Centers of Cyclohexadienones by Rhodium-Catalyzed Conjugate Hydrosilylation. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601636] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yuki Naganawa
- Department of Applied Chemistry; Graduate School of Engineering; Nagoya University; Chikusa Nagoya 464-8603 Japan
| | - Mayu Kawagishi
- Department of Applied Chemistry; Graduate School of Engineering; Nagoya University; Chikusa Nagoya 464-8603 Japan
| | - Jun-ichi Ito
- Department of Applied Chemistry; Graduate School of Engineering; Nagoya University; Chikusa Nagoya 464-8603 Japan
| | - Hisao Nishiyama
- Department of Applied Chemistry; Graduate School of Engineering; Nagoya University; Chikusa Nagoya 464-8603 Japan
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21
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Naganawa Y, Kawagishi M, Ito JI, Nishiyama H. Asymmetric Induction at Remote Quaternary Centers of Cyclohexadienones by Rhodium-Catalyzed Conjugate Hydrosilylation. Angew Chem Int Ed Engl 2016; 55:6873-6. [DOI: 10.1002/anie.201601636] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Yuki Naganawa
- Department of Applied Chemistry; Graduate School of Engineering; Nagoya University; Chikusa Nagoya 464-8603 Japan
| | - Mayu Kawagishi
- Department of Applied Chemistry; Graduate School of Engineering; Nagoya University; Chikusa Nagoya 464-8603 Japan
| | - Jun-ichi Ito
- Department of Applied Chemistry; Graduate School of Engineering; Nagoya University; Chikusa Nagoya 464-8603 Japan
| | - Hisao Nishiyama
- Department of Applied Chemistry; Graduate School of Engineering; Nagoya University; Chikusa Nagoya 464-8603 Japan
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22
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Le Bailly BAF, Byrne L, Clayden J. Refoldable Foldamers: Global Conformational Switching by Deletion or Insertion of a Single Hydrogen Bond. Angew Chem Int Ed Engl 2016; 55:2132-6. [PMID: 26762559 PMCID: PMC4755161 DOI: 10.1002/anie.201510605] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Indexed: 11/12/2022]
Abstract
Small changes in the structure of a foldamer may lead to gross changes in conformational preference. We show that the simple insertion or deletion of a single hydrogen bond by changes in pH or by photochemical deprotection is sufficient to refold a helical oligomer, interconverting M and P screw-sense preference. As a consequence of the switch, information may be transmitted to a remote catalytic site, selectively directing the formation of either of two enantiomeric products by a reaction involving 1,22-remote intermolecular asymmetric induction.
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Affiliation(s)
- Bryden A F Le Bailly
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.,School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Liam Byrne
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Jonathan Clayden
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
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23
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Le Bailly BAF, Byrne L, Clayden J. Refoldable Foldamers: Global Conformational Switching by Deletion or Insertion of a Single Hydrogen Bond. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201510605] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Bryden A. F. Le Bailly
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
- School of Chemistry; University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Liam Byrne
- School of Chemistry; University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Jonathan Clayden
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
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24
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Verma A, Baishya B. Real-Time Band-Selective Homonuclear Proton Decoupling for Improving Sensitivity and Resolution in Phase-SensitiveJ-Resolved Spectroscopy. Chemphyschem 2015; 16:2687-91. [DOI: 10.1002/cphc.201500377] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Indexed: 11/06/2022]
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25
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Bai XF, Song T, Xu Z, Xia CG, Huang WS, Xu LW. Aromatic Amide-Derived Non-Biaryl Atropisomers as Highly Efficient Ligands in Silver-Catalyzed Asymmetric Cycloaddition Reactions. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201501100] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Bai XF, Song T, Xu Z, Xia CG, Huang WS, Xu LW. Aromatic Amide-Derived Non-Biaryl Atropisomers as Highly Efficient Ligands in Silver-Catalyzed Asymmetric Cycloaddition Reactions. Angew Chem Int Ed Engl 2015; 54:5255-9. [DOI: 10.1002/anie.201501100] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Indexed: 12/14/2022]
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27
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Pike SJ, Diemer V, Raftery J, Webb SJ, Clayden J. Designing foldamer-foldamer interactions in solution: the roles of helix length and terminus functionality in promoting the self-association of aminoisobutyric acid oligomers. Chemistry 2014; 20:15981-90. [PMID: 25280242 DOI: 10.1002/chem.201403626] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Indexed: 12/11/2022]
Abstract
The biological activity of antibiotic peptaibols has been linked to their ability to aggregate, but the structure-activity relationship for aggregation is not well understood. Herein, we report a systematic study of a class of synthetic helical oligomer (foldamer) composed of aminoisobutyric acid (Aib) residues, which mimic the folding behavior of peptaibols. NMR spectroscopic analysis was used to quantify the dimerization constants in solution, which showed hydrogen-bond donors at the N terminus promoted aggregation more effectively than similar modifications at the C terminus. Elongation of the peptide chain also favored aggregation. The geometry of aggregation in solution was investigated by means of titrations with [D6]DMSO and 2D NOE NMR spectroscopy, which allowed the NH protons most involved in intermolecular hydrogen bonds in solution to be identified. X-ray crystallography studies of two oligomers allowed a comparison of the inter- and intramolecular hydrogen-bonding interactions in the solid state and in solution and gave further insight into the geometry of foldamer-foldamer interactions. These solution-based and solid-state studies indicated that the preferred geometry for aggregation is through head-to-tail interactions between the N and C termini of adjacent Aib oligomers.
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Affiliation(s)
- Sarah J Pike
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL (UK), Fax: (+44) 161-275-4939
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28
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Johnston CP, Smith MD. Ferngesteuerte Stereokontrolle durch helikale Strukturen. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201400154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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29
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Johnston CP, Smith MD. Remote Stereocontrol Transmitted through Helicity. Angew Chem Int Ed Engl 2014; 53:3315-7. [DOI: 10.1002/anie.201400154] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Indexed: 11/07/2022]
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30
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Bai XF, Deng WH, Xu Z, Li FW, Deng Y, Xia CG, Xu LW. Silicon-Based Bulky Group-Induced Remote Control and Conformational Preference in the Synthesis and Application of Isolable Atropisomeric Amides with Secondary Alcohol or Amine Moieties. Chem Asian J 2014; 9:1108-15. [DOI: 10.1002/asia.201301727] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Indexed: 11/09/2022]
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31
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Adams RW, Byrne L, Király P, Foroozandeh M, Paudel L, Nilsson M, Clayden J, Morris GA. Diastereomeric ratio determination by high sensitivity band-selective pure shift NMR spectroscopy. Chem Commun (Camb) 2014; 50:2512-4. [PMID: 24458213 DOI: 10.1039/c3cc49659g] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An NMR method is reported that allows diastereomeric ratios to be determined even in crowded spectra or where chemical shift differences are small compared to multiplet widths. Band-selective pure shift NMR collapses multiplets to singlets, greatly improving spectral resolution while largely retaining, or even enhancing, signal-to-noise ratio.
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Affiliation(s)
- Ralph W Adams
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
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