1
|
Dash SR, Sharma H, Tiwari MK, Greb L, Vanka K. Size Matters: Computational Insights into the Crowning of Noble Gas Trioxides. Inorg Chem 2024; 63:4099-4107. [PMID: 38373012 DOI: 10.1021/acs.inorgchem.3c03782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
In pursuit of enhancing the stability of the highly explosive and shock-sensitive compound XeO3, we performed quantum chemical calculations to investigate its possible complexation with electron-rich crown ethers, including 9-crown-3, 12-crown-4, 15-crown-5, 18-crown-6, and 21-crown-7, as well as their thio analogues. Furthermore, we expanded our study to other noble gas trioxides (NgO3), namely, KrO3 and ArO3. The basis set superposition error (BSSE) corrected interaction energies for these adducts range from -13.0 kcal/mol to -48.2 kcal/mol, which is notably high for σ-hole-mediated noncovalent interactions. The formation of these adducts was observed to be more favorable with the increase in the ring size of the crowns and less favorable while going from XeO3 to ArO3. A comprehensive analysis by various computational tools such as the mapping of the electrostatic potential (ESP), Wiberg bond indices (WBIs), Bader's theory of atoms-in-molecules (AIM), natural bond orbital (NBO) analysis, noncovalent interaction (NCI) plots, and energy decomposition analysis (EDA) revealed that the C-H···O interactions, as well as dispersion interactions, play a pivotal role in stabilizing adducts involving larger crowns. A noteworthy outcome of our study is the revelation of a coordination number of 9 for xenon in the complex formed between XeO3 and the thio analogue of 18-crown-6, which is higher than the largest number reported to date.
Collapse
Affiliation(s)
- Soumya Ranjan Dash
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Himanshu Sharma
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | | | - Lutz Greb
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Kumar Vanka
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| |
Collapse
|
2
|
Chalcogenolato-bridged rhenium(I)-based ester functionalized flexible dinuclear metallacrown ethers: Cation binding, molecular recognition and docking studies. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.116084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
3
|
McNeil BL, Kadassery KJ, McDonagh AW, Zhou W, Schaffer P, Wilson JJ, Ramogida CF. Evaluation of the Effect of Macrocyclic Ring Size on [ 203Pb]Pb(II) Complex Stability in Pyridyl-Containing Chelators. Inorg Chem 2022; 61:9638-9649. [PMID: 35704752 DOI: 10.1021/acs.inorgchem.2c01114] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As an element-equivalent theranostic pair, lead-203 (203Pb, 100% EC, half-life = 51.92 h) and lead-212 (212Pb, 100% β-, half-life = 10.64 h), through the emission of γ rays and an α particle in its decay chain, respectively, can aid in the development of personalized targeted radionuclide treatment for advanced and currently untreatable cancers. With these isotopes currently being used in clinical trials, an understanding of the relationship between the chelator structure, ability to incorporate the radiometal, and metal-complex stability is needed to help design appropriate chelators for clinical use. Herein, we report an investigation into the effect of ring size in macrocyclic chelators where pyridine, an intermediate Lewis base, acts as an electron donor toward lead. Crown-4Py (4,7,13,16-tetrakis(pyridin-2-ylmethyl)-1,10-dioxa-4,7,13,16-tetraazacyclooctadecane), cyclen-4Py (1,4,7,10-tetrakis(pyridin-2-ylmethyl)-1,4,7,10-tetraazacyclododecane), and NOON-2Py (7,16-bis(pyridin-2-ylmethyl)-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane) were synthesized and analyzed for their ability to coordinate Pb2+. Metal complex stability was investigated via [203Pb]Pb2+ radiolabeling studies, 1H NMR spectroscopy, X-ray crystallography, and potentiometry. With the smallest macrocyclic backbone, cyclen-4Py had the highest radiochemical yield, while, in descending order, crown-4Py and NOON-2Py had the lowest. Thermodynamic stability constants (log KML) of 19.95(3), 13.29(5), and 11.67 for [Pb(Cyclen-4Py)]2+, [Pb(Crown-4Py)]2+, and [Pb(NOON-2Py)]2+, respectively, correlated with their radiochemical yields. The X-ray crystal structure of the least stable complexes [Pb(NOON-2Py)]2+ revealed a hemidirected Pb2+ center, as reflected by a void within the coordination sphere, and [Pb(Crown-4Py)]2+ showed an average Pb-N pyridine interatomic distance of >3 Å. By contrast, the crystal structure of [Pb(Cyclen-4Py)]2+ showed shorter Pb-N pyridine interactions, and in solution, only one highly symmetric isomer existed for this complex, whereas conformational flexibility was observed for both [Pb(Crown-4Py)]2+ and [Pb(NOON-2Py)]2+ at the NMR timescale. This study illustrates the importance of the macrocyclic backbone size when incorporating bulky electron-donor groups into the design of a macrocyclic chelator as it affects the accessibility of lead to the donor arms. Our results show that cyclen-4Py is a promising chelator for future studies with this theranostic pair.
Collapse
Affiliation(s)
- Brooke L McNeil
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.,Life Sciences Division, TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - Karthika J Kadassery
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca New York, 14853-1301 United States
| | - Anthony W McDonagh
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Wen Zhou
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Paul Schaffer
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.,Life Sciences Division, TRIUMF, Vancouver, British Columbia V6T 2A3, Canada.,Department of Radiology, The University of British Columbia, Vancouver, British Columbia V5Z 1M9, Canada
| | - Justin J Wilson
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca New York, 14853-1301 United States
| | - Caterina F Ramogida
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.,Life Sciences Division, TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| |
Collapse
|
4
|
Varadwaj A, Varadwaj PR, Marques HM, Yamashita K. The Stibium Bond or the Antimony-Centered Pnictogen Bond: The Covalently Bound Antimony Atom in Molecular Entities in Crystal Lattices as a Pnictogen Bond Donor. Int J Mol Sci 2022; 23:ijms23094674. [PMID: 35563065 PMCID: PMC9099767 DOI: 10.3390/ijms23094674] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 04/16/2022] [Accepted: 04/18/2022] [Indexed: 12/04/2022] Open
Abstract
A stibium bond, i.e., a non-covalent interaction formed by covalently or coordinately bound antimony, occurs in chemical systems when there is evidence of a net attractive interaction between the electrophilic region associated with an antimony atom and a nucleophile in another, or the same molecular entity. This is a pnictogen bond and are likely formed by the elements of the pnictogen family, Group 15, of the periodic table, and is an inter- or intra-molecular non-covalent interaction. This overview describes a set of illustrative crystal systems that were stabilized (at least partially) by means of stibium bonds, together with other non-covalent interactions (such as hydrogen bonds and halogen bonds), retrieved from either the Cambridge Structure Database (CSD) or the Inorganic Crystal Structure Database (ICSD). We demonstrate that these databases contain hundreds of crystal structures of various dimensions in which covalently or coordinately bound antimony atoms in molecular entities feature positive sites that productively interact with various Lewis bases containing O, N, F, Cl, Br, and I atoms in the same or different molecular entities, leading to the formation of stibium bonds, and hence, being partially responsible for the stability of the crystals. The geometric features, pro-molecular charge density isosurface topologies, and extrema of the molecular electrostatic potential model were collectively examined in some instances to illustrate the presence of Sb-centered pnictogen bonding in the representative crystal systems considered.
Collapse
Affiliation(s)
- Arpita Varadwaj
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan; (A.V.); (K.Y.)
| | - Pradeep R. Varadwaj
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan; (A.V.); (K.Y.)
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg 2050, South Africa;
- Correspondence:
| | - Helder M. Marques
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg 2050, South Africa;
| | - Koichi Yamashita
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan; (A.V.); (K.Y.)
| |
Collapse
|
5
|
McDonagh AW, McNeil BL, Patrick BO, Ramogida CF. Synthesis and Evaluation of Bifunctional [2.2.2]-Cryptands for Nuclear Medicine Applications. Inorg Chem 2021; 60:10030-10037. [PMID: 34159785 DOI: 10.1021/acs.inorgchem.1c01274] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
For the first time, synthesis of bifunctional [2.2.2]-cryptands (CRYPT) and demonstration of radiolabeling with lead(II) (Pb2+) isotopes are disclosed herein. The synthesis is convenient and high-yielding and gives access to three distinct bifunctional handles (azide (-N3), isothiocyanate (-NCS), and tetrazine (-Tz)) that can enable the construction of radioimmunoconjugates for targeted and pretargeted therapy. Proof-of-principle CRYPT radiolabeling was successful with lead-203 ([203Pb]Pb2+) and demonstrated complexation efficiency superior to that of DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and efficiency comparable to that of the current industry standard TCMC (1,4,7,10-tetraaza-1,4,7,10-tetra-(2-carbamoylmethyl)-cyclododecane). In vitro human serum stability assays demonstrated excellent [203Pb]Pb-CRYPT stability over 72 h (91.7 ± 0.56%; n = 3). [203Pb]Pb-CRYPT-radioimmunoconjugates were synthesized from the corresponding CRYPT-immunoconjugate or by conjugating [203Pb]Pb-Tz-CRYPT to transcyclooctene modified trastuzumab (TCO-trastuzumab) via the inverse electron-demand Diels-Alder (IEEDA) reaction. This investigation reveals the potential for CRYPT ligands to become new industry standards for therapeutic and diagnostic radiometals in radiopharmaceutical elaboration.
Collapse
Affiliation(s)
- Anthony W McDonagh
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Brooke L McNeil
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.,Life Sciences Division, TRIUMF, Vancouver, BC V6T 2A3, Canada
| | - Brian O Patrick
- Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Caterina F Ramogida
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.,Life Sciences Division, TRIUMF, Vancouver, BC V6T 2A3, Canada
| |
Collapse
|
6
|
Dabringhaus P, Barthélemy A, Krossing I. The Coordination Chemistry and Clustering of Subvalent Ga
+
and In
+
upon Addition of σ‐Donor Ligands. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202100129] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Philipp Dabringhaus
- Institut für Anorganische und Analytische Chemie and Freiburg Materials Research Center FMF Albert-Ludwigs-Universität Freiburg Albertstraße 21 79104 Freiburg i.Br. Germany
| | - Antoine Barthélemy
- Institut für Anorganische und Analytische Chemie and Freiburg Materials Research Center FMF Albert-Ludwigs-Universität Freiburg Albertstraße 21 79104 Freiburg i.Br. Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie and Freiburg Materials Research Center FMF Albert-Ludwigs-Universität Freiburg Albertstraße 21 79104 Freiburg i.Br. Germany
| |
Collapse
|
7
|
Dankert F, Richter R, Weigend F, Xie X, Balmer M, Hänisch C. Aufbau anorganischer Kronenether durch s‐Block‐Metall‐templatgesteuerte Si‐O‐Bindungsaktivierung. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014822] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Fabian Dankert
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - Roman‐Malte Richter
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - Florian Weigend
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - Xiulan Xie
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - Markus Balmer
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - Carsten Hänisch
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| |
Collapse
|
8
|
Dankert F, Richter R, Weigend F, Xie X, Balmer M, von Hänisch C. Construction of Inorganic Crown Ethers by s-Block-Metal-Templated Si-O Bond Activation. Angew Chem Int Ed Engl 2021; 60:10393-10401. [PMID: 33591587 PMCID: PMC8252370 DOI: 10.1002/anie.202014822] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/01/2021] [Indexed: 11/07/2022]
Abstract
We herein report the synthesis, structures, coordination ability, and mechanism of formation of silicon analogs of crown ethers. An oligomerization of 2 D2 (I) (2 Dn ,=(Me4 Si2 O)n ) was achieved by the reaction with GaI3 and MIx (M=Li, Na, Mg, Ca, Sr). In these reactions the metal cations serve as template and the anions (I- /[GaI4 ]- ) are required as nucleophiles. In case of MIx =LiI, [Li(2 D3 )GaI4 ] (1) is formed. In case of MIx =NaI, MgI2 , CaI2 , and SrI2 the compounds [M(2 D4 )(GaI4 )x ] (M=Mg2+ (3), Ca2+ (4), Sr2+ (5) are obtained. Furthermore the proton complex [H(2 D3 )][Ga2 I7 ] (6) was isolated and structurally characterized. All complexes were characterized by means of multinuclear NMR spectroscopy, DOSY experiments and, except for compound 3, also by single crystal X-ray diffraction. Quantum chemical calculations were carried out to compare the affinity of M+ to 2 Dn and other ligands and to shed light on the formation of larger rings from smaller ones.
Collapse
Affiliation(s)
- Fabian Dankert
- Fachbereich ChemiePhilipps-Universität MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - Roman‐Malte Richter
- Fachbereich ChemiePhilipps-Universität MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - Florian Weigend
- Fachbereich ChemiePhilipps-Universität MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - Xiulan Xie
- Fachbereich ChemiePhilipps-Universität MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - Markus Balmer
- Fachbereich ChemiePhilipps-Universität MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - Carsten von Hänisch
- Fachbereich ChemiePhilipps-Universität MarburgHans-Meerwein-Strasse 435032MarburgGermany
| |
Collapse
|
9
|
Fang Y, Dehaen W. Small-molecule-based fluorescent probes for f-block metal ions: A new frontier in chemosensors. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2020.213524] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
10
|
Zhang S, Wang Z, Cao Q, Yue E, Liu Q, Ma Y, Liang T, Sun WH. Aza-crown compounds synthesised by the self-condensation of 2-amino-benzyl alcohol over a pincer ruthenium catalyst and applied in the transfer hydrogenation of ketones. Dalton Trans 2020; 49:15821-15827. [PMID: 33151229 DOI: 10.1039/d0dt03257c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A well-defined PNN-Ru catalyst was revisited to self-condense 2-aminobenzyl alcohol in forming a series of novel aza-crown compounds [aza-12-crown-3 (1), aza-16-crown-4 (2) and aza-20-crown-5 (3)]. All aza-crown compounds are separated and determined by NMR, IR, and ESI-MS spectroscopy as well as X-ray crystallography, indicating the saddle structure of 1 and the twisted 1,3-alternate conformation structure of 3. These aza-crown compounds have been explored to study ferric initiation of transfer hydrogenation (TH) of ketones into their corresponding secondary alcohols in the presence of 2-propanol with a basic t-BuOK solution, achieving a high conversion (up to 95%) by a ferric complex with 2 in a low loading (0.05 mol%).
Collapse
Affiliation(s)
- Shanshan Zhang
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024, China.
| | - Zheng Wang
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024, China. and Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and College of Science, Hebei Agricultural University, Baoding 071001, China
| | - Qianrong Cao
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024, China. and Hebei Research Institute of Microbiology, Baoding 071051, China
| | - Erlin Yue
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Qingbin Liu
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024, China.
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Tongling Liang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Wen-Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| |
Collapse
|
11
|
Mukherjee A, Ghule S, Tiwari MK, Vanka K. Unraveling the Hidden Role of the Counteranion in "Cation in a Cage" Systems. J Phys Chem A 2020; 124:8040-8049. [PMID: 32894677 DOI: 10.1021/acs.jpca.0c06995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The current work showcases general principles at play in systems consisting of cations present inside molecular cages. Such systems, relevant to chemistry and biology, have been carefully investigated by computational methods. The important Ge(II)-encapsulating cage systems have been studied first. The very fact that such compounds exist appears highly unlikely, given the highly reactive nature of the Ge(II) dication. Our studies reveal what really occurs in solution when such complexes are formed: the Ge(II) dications are actually present as [Ge-X]+ (where X is the "non-coordinating" counterion employed in such systems) during entry and subsequent existence at the center of the cage. Hence, what is actually present is a "pseudomonocation". Interestingly, such pseudomonocation-encapsulated cages are seen to be equally relevant in systems of biological importance, such as for dicationic s block-based ionophores. In explaining such cases, the concept of "isoionicity" is introduced, demonstrating that the counterion-coordinated dications are isoionic with a monocation, such as Li(I), isolated in the same ionophore.
Collapse
Affiliation(s)
- Anagh Mukherjee
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Siddharth Ghule
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Mrityunjay K Tiwari
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal 462066, India
| | - Kumar Vanka
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| |
Collapse
|
12
|
Highly selective extraction of palladium from spent automotive catalyst acid leachate using novel alkylated dioxa-dithiacrown ether derivatives. J IND ENG CHEM 2020. [DOI: 10.1016/j.jiec.2020.06.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
13
|
Novel polymer crafted sugar thiacrown ether and its applications in recovery of metal ions. Carbohydr Res 2020; 495:108057. [DOI: 10.1016/j.carres.2020.108057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/22/2020] [Accepted: 06/01/2020] [Indexed: 11/22/2022]
|
14
|
Glootz K, Kratzert D, Krossing I. Synthesis and Structural Characterization of Gallium(I) and Indium(I) Cations Coordinated by Pentamethylethylenediamine. Z Anorg Allg Chem 2020. [DOI: 10.1002/zaac.202000170] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Kim Glootz
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Daniel Kratzert
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| |
Collapse
|
15
|
Schröder J, Böttcher T. 2,6‐Bis(diazaboryl)pyridine – A Ligand with Hemilabile Donor and Lewis Acid Functionalities. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201901164] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jan Schröder
- Institut für Anorganische und Analytische Chemie Universität Freiburg Albertstr. 19 79104 Freiburg Germany
| | - Tobias Böttcher
- Institut für Anorganische und Analytische Chemie Universität Freiburg Albertstr. 19 79104 Freiburg Germany
| |
Collapse
|
16
|
Glootz K, Himmel D, Kratzert D, Butschke B, Scherer H, Krossing I. Why Do Five Ga
+
Cations Form a Ligand‐Stabilized [Ga
5
]
5+
Pentagon and How Does a 5:1 Salt Pack in the Solid State? Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201907974] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Kim Glootz
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Daniel Himmel
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Daniel Kratzert
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Burkhard Butschke
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Harald Scherer
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF) Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| |
Collapse
|
17
|
Glootz K, Himmel D, Kratzert D, Butschke B, Scherer H, Krossing I. Why Do Five Ga + Cations Form a Ligand-Stabilized [Ga 5 ] 5+ Pentagon and How Does a 5:1 Salt Pack in the Solid State? Angew Chem Int Ed Engl 2019; 58:14162-14166. [PMID: 31369694 PMCID: PMC6790617 DOI: 10.1002/anie.201907974] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 07/31/2019] [Indexed: 11/12/2022]
Abstract
The reaction of the Ga+ source [Ga(PhF)2 ]+ [Al(ORF )4 ]- with the neutral σ-donor ligand dmap (4-Me2 N-C6 H4 N) produces the unexpectedly large and fivefold positively charged cluster cation salt [Ga5 (dmap)10 ]5+ ([Al(ORF )4 ]- )5 . It includes a regular and planar Ga5 pentagon with strong metal-metal bonding. Additionally, the compound represents the first salt in which an ionic 1:5 packing is realized. We discuss the nature of this structure which results from the conversion of the non-bonding 4s2 lone-pair orbitals into fully Ga-Ga-bonding orbitals and the solid-state arrangement of the ions constituting the lattice as an almost orthohexagonal AX5 lattice, possibly the aristotype of any 5:1 salt.
Collapse
Affiliation(s)
- Kim Glootz
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Daniel Himmel
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Daniel Kratzert
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Burkhard Butschke
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Harald Scherer
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| |
Collapse
|
18
|
Zhang Y, Ouyang Y, Luo Z, Dong S. Convenient, Column Chromatography-Free, and Effective Synthesis of Benzo-21-crown-7 and Its Derivatives. European J Org Chem 2019. [DOI: 10.1002/ejoc.201900712] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Yi Zhang
- College of Chemistry and Chemical Engineering; Hunan University; 410082 Changsha Hunan P. R. China
| | - Yunyun Ouyang
- College of Chemistry and Chemical Engineering; Hunan University; 410082 Changsha Hunan P. R. China
| | - Zheng Luo
- College of Chemistry and Chemical Engineering; Hunan University; 410082 Changsha Hunan P. R. China
| | - Shengyi Dong
- College of Chemistry and Chemical Engineering; Hunan University; 410082 Changsha Hunan P. R. China
| |
Collapse
|
19
|
Hu SX, Jian J, Li J, Gibson JK. Destruction of the Uranyl Moiety in a U(V) “Cation–Cation” Interaction. Inorg Chem 2019; 58:10148-10159. [DOI: 10.1021/acs.inorgchem.9b01265] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shu-Xian Hu
- Beijing Computational Science Research Center, Beijing 100193, China
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Jiwen Jian
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jun Li
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - John K. Gibson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| |
Collapse
|
20
|
Affiliation(s)
- Teresa L. Mako
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
| | - Joan M. Racicot
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
| | - Mindy Levine
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
| |
Collapse
|
21
|
Kamimura A, Watanabe R, Fukumitsu T, Ikeda K, Kawamoto T, Sumimoto M, Mori S, Uno H. Deltaarenes; novel macrocyclic molecules that are readily available from 1,4-benzoquinone and benzene dithiols. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.04.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
22
|
Secara AM, Binder JF, Swidan A, Macdonald CL. Synthesis and structural characterization of new polyether complexes of germanium(II) and tin(II). CAN J CHEM 2018. [DOI: 10.1139/cjc-2017-0763] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A series of germanium(II) and tin(II) bromide polyether complexes have been synthesized. Specifically, [GeBr([15]crown-5)][GeBr3], [GeBr([18]crown-6)][GeBr3], [GeBr(triglyme)][GeBr3], [GeBr(tetraglyme)][GeBr3], [SnBr([18]crown-6)][SnBr3], [Sn([15]crown-5)2][SnBr3]2, [SnBr(triglyme)][SnBr3], and [SnBr(tetraglyme)][SnBr3] have been fully characterized including by single crystal X-ray diffraction. The synthesis of [GeBr(dibenzo[24]crown-8)][GeBr3] and [GeCl(dibenzo[24]crown-8)][GeCl3] are also reported, along with the crystal structure of the latter’s water adduct, which features a water molecule adjacent to the GeCl+ ion within the cavity of the crown ether.
Collapse
Affiliation(s)
- Alina M. Secara
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada
| | - Justin F. Binder
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada
| | - Ala’aeddeen Swidan
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada
| | - Charles L.B. Macdonald
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada
| |
Collapse
|
23
|
Vishe M, Lathion T, Pascal S, Yushchenko O, Homberg A, Brun E, Vauthey E, Piguet C, Lacour J. Excimer-Based On-Off Bis(pyreneamide) Macrocyclic Chemosensors. Helv Chim Acta 2017. [DOI: 10.1002/hlca.201700265] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Mahesh Vishe
- Department of Organic Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| | - Timothée Lathion
- Department of Inorganic and Analytical Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| | - Simon Pascal
- Department of Organic Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| | - Oleksandr Yushchenko
- Department of Physical Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| | - Alexandre Homberg
- Department of Organic Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| | - Elodie Brun
- Department of Organic Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| | - Eric Vauthey
- Department of Physical Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| | - Claude Piguet
- Department of Inorganic and Analytical Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| | - Jérôme Lacour
- Department of Organic Chemistry; University of Geneva; Quai Ernest Ansermet 30 1211 Geneva Switzerland
| |
Collapse
|
24
|
Jamali SH, Ramdin M, Becker TM, Rinwa SK, Buijs W, Vlugt TJH. Thermodynamic and Transport Properties of Crown-Ethers: Force Field Development and Molecular Simulations. J Phys Chem B 2017; 121:8367-8376. [PMID: 28792215 PMCID: PMC5592649 DOI: 10.1021/acs.jpcb.7b06547] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Crown-ethers have recently been used to assemble porous liquids (PLs), which are liquids with permanent porosity formed by mixing bulky solvent molecules (e.g., 15-crown-5 ether) with solvent-inaccessible organic cages. PLs and crown-ethers belong to a novel class of materials, which can potentially be used for gas separation and storage, but their performance for this purpose needs to be assessed thoroughly. Here, we use molecular simulations to study the gas separation performance of crown-ethers as the solvent of porous liquids. The TraPPE force field for linear ether molecules has been adjusted by fitting a new set of torsional potentials to accurately describe cyclic crown-ether molecules. Molecular dynamics (MD) simulations have been used to compute densities, shear viscosities, and self-diffusion coefficients of 12-crown-4, 15-crown-5, and 18-crown-6 ethers. In addition, Monte Carlo (MC) simulations have been used to compute the solubility of the gases CO2, CH4, and N2 in 12-crown-4 and 15-crown-5 ether. The computed properties are compared with available experimental data of crown-ethers and their linear counterparts, i.e., polyethylene glycol dimethyl ethers.
Collapse
Affiliation(s)
- Seyed Hossein Jamali
- Engineering Thermodynamics, Process & Energy Department, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology , Leeghwaterstraat 39, 2628CB Delft, The Netherlands
| | - Mahinder Ramdin
- Engineering Thermodynamics, Process & Energy Department, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology , Leeghwaterstraat 39, 2628CB Delft, The Netherlands
| | - Tim M Becker
- Engineering Thermodynamics, Process & Energy Department, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology , Leeghwaterstraat 39, 2628CB Delft, The Netherlands
| | - Shwet Kumar Rinwa
- Engineering Thermodynamics, Process & Energy Department, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology , Leeghwaterstraat 39, 2628CB Delft, The Netherlands
| | - Wim Buijs
- Engineering Thermodynamics, Process & Energy Department, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology , Leeghwaterstraat 39, 2628CB Delft, The Netherlands
| | - Thijs J H Vlugt
- Engineering Thermodynamics, Process & Energy Department, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology , Leeghwaterstraat 39, 2628CB Delft, The Netherlands
| |
Collapse
|
25
|
Zhao Q, Yu LT, Luo BM, Liu XD, Liu SJ. Construction and properties investigation of propeller type and three-fold interpenetration topology Mn(II) complexes. Inorganica Chim Acta 2017. [DOI: 10.1016/j.ica.2017.04.063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
26
|
Lebedev YN, Das U, Schnakenburg G, Filippou AC. Coordination Chemistry of [E(Idipp)]2+ Ligands (E = Ge, Sn): Metal Germylidyne [Cp*(CO)2W≡Ge(Idipp)]+ and Metallotetrylene [Cp*(CO)3W–E(Idipp)]+ Cations. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00110] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yury N. Lebedev
- Institut für Anorganische
Chemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany
| | - Ujjal Das
- Institut für Anorganische
Chemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany
| | - Gregor Schnakenburg
- Institut für Anorganische
Chemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany
| | - Alexander C. Filippou
- Institut für Anorganische
Chemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany
| |
Collapse
|
27
|
Rasheed OK, McDouall JJW, Muryn CA, Raftery J, Vitorica-Yrezabal IJ, Quayle P. The assembly of “S3N”-ligands decorated with an azo-dye as potential sensors for heavy metal ions. Dalton Trans 2017; 46:5229-5239. [DOI: 10.1039/c7dt00569e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The synthesis and complexation of azo dye-S3N crown conjugates with Ag(i), Cu(ii) and Hg(ii) is described.
Collapse
Affiliation(s)
- O. K. Rasheed
- School of Chemistry
- University of Manchester
- Manchester M13 9PL
- UK
| | | | - C. A. Muryn
- School of Chemistry
- University of Manchester
- Manchester M13 9PL
- UK
| | - J. Raftery
- School of Chemistry
- University of Manchester
- Manchester M13 9PL
- UK
| | | | - P. Quayle
- School of Chemistry
- University of Manchester
- Manchester M13 9PL
- UK
| |
Collapse
|
28
|
Kosnik SC, Nascimento MC, Rawson JM, Macdonald CLB. Synthesis of bis(trithio)phosphines by oxidative transfer of phosphorus(i). Dalton Trans 2017; 46:9769-9776. [DOI: 10.1039/c7dt01345k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the oxidative transfer of the phosphorus(i) centre in [PIdppe][Br] to tetrathiocin and disulfide ligands. Characterization of the resulting bis(trithio)phosphines and mechanistic insight into the formation of these products is provided.
Collapse
Affiliation(s)
| | | | - Jeremy M. Rawson
- Dept of Chemistry & Biochemistry
- The University of Windsor
- Windsor
- Canada
| | | |
Collapse
|
29
|
Green MLH, Parkin G. The classification and representation of main group element compounds that feature three-center four-electron interactions. Dalton Trans 2016; 45:18784-18795. [PMID: 27845802 DOI: 10.1039/c6dt03570a] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This article provides a means to classify and represent compounds that feature 3-center 4-electron (3c-4e) interactions in terms of the number of electrons that each atom contributes to the interaction. Specifically, Class I 3c-4e interactions are classified as those in which two atoms provide one electron each and the third atom provides a pair of electrons (i.e. LX2), while Class II 3c-4e interactions are classified as those in which two atoms each provide a pair of electrons and the third atom contributes none (i.e. L2Z). These classes can be subcategorized according to the nature of the central atom. Thus, Class I interactions can be categorized according to whether the central atom provides one (i.e.μ-X) or two (i.e.μ-L) electrons, while Class II interactions can be categorized according to whether the central atom provides none (i.e.μ-Z) or two (i.e.μ-L) electrons. The use of appropriate structure-bonding representations for these various interactions provides a means to determine the covalent bond classification of the element of interest.
Collapse
Affiliation(s)
- Malcolm L H Green
- Inorganic Chemistry Laboratory, South Parks Road, Oxford, UK OX1 3QR.
| | | |
Collapse
|
30
|
Agrawal N, Skelton AA. 12-Crown-4 Ether Disrupts the Patient Brain-Derived Amyloid-β-Fibril Trimer: Insight from All-Atom Molecular Dynamics Simulations. ACS Chem Neurosci 2016; 7:1433-1441. [PMID: 27454141 DOI: 10.1021/acschemneuro.6b00185] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Recent experimental data elucidated that 12-crown-4 ether molecule can disrupt Aβ40 fibrils but the mechanism of disruption remains elusive. We have performed a series of all-atom molecular dynamics simulations to study the molecular mechanism of Aβ40 fibril disruption by 12-crown-4. In the present study we have used the Aβ40 fibril trimer as it is the smallest unit that maintains a stable U-shaped structure, and serves as the nucleus to form larger fibrils. Our study reveals that 12-crown-4 ether can enter into the hydrophobic core region and form competitive, hydrophobic interactions with key hydrophobic residues; these interactions break the intersheet hydrophobic interactions and lead to the opening of the U-shaped topology and a loss of β-sheet structure. Furthermore, we observed periods of time when 12-crown-4 was in the hydrophobic core and periods of time when it interacted with Lys28 (chain C), a "tug of war"; the 12-crown-4 binding with Lys28 destabilizes the salt-bridge between Asp23 and Lys28. In addition to the two aforementioned binding modes, the 12-crown-4 binds with Lys16, which is known to form a salt-bridge with Glu22 in antiparallel arranged Aβ fibrils. Our results are in good agreement with experimental results and suggest that molecules that have the ability to interact with both the hydrophobic core region and positively charged residues could serve as potential inhibitors of Aβ fibrils.
Collapse
Affiliation(s)
- Nikhil Agrawal
- School
of Pharmacy and Pharmacology, University of KwaZulu-Natal, Durban 4001, South Africa
| | - Adam A. Skelton
- School
of Pharmacy and Pharmacology, University of KwaZulu-Natal, Durban 4001, South Africa
| |
Collapse
|