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Bhunia S, Sahoo D, Maity S, Dutta B, Bera S, Manik NB, Sinha C. Aminoisophthalate Bridged Cd(II)-2D Coordination Polymer: Structure Description, Selective Detection of Pd 2+ in Aqueous Medium, and Fabrication of Schottky Diode. Inorg Chem 2023. [PMID: 37467437 DOI: 10.1021/acs.inorgchem.3c01421] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
Photoluminescence activity of coordination polymers (CPs) has evoked intricate applications in the field of materials science, especially sensing of ions/molecules. In the present study, 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) and 5-aminoisophthalate (HAIPA-) coordinated to Cd(II) to architect a coordination polymer, {[Cd(HAIPA)(tppz)(OH)]·3H2O}n (CP1) which unveils blue emission in an aqueous acetonitrile (98% aqueous) suspension. The emission is selectively quenched by Pd2+ only without interference in the presence of as many as 16 other cations. The structure of CP1 shows the presence of a free -COOH group, and the interlayer (-CO)O(2)···O(7) (OC-) distance, 4.242 Å, along with the π···π interactions (3.990, 3.927 Å), may make a cavity which suitably accommodates only Pd2+ (van der Waal's radius, 1.7 Å) through the Pd(II)-carboxylato (-COO-Pd) coordination. The stability of the composite, [CP1 + Pd2+] may be assessed from the fluorescence quenching experiment, and the Stern-Volmer constant (KSV) is 7.2 × 104 M-1. Therefore, the compound, CP1, is a promising sensor for Pd(II) in a selective manner with limit of detection (LOD), 0.08 μM. The XPS spectra of CP1 and [CP1 + Pd2+] have proven the presence of Pd2+ in the host and the existence of a coordinated -COO-Pd bond. Interestingly, inclusion of Pd2+ in CP1 decreases the band gap from 3.61 eV (CP1) to 3.05 eV ([CP1 + Pd2+]) which lies in the semiconducting region and has exhibited improved electrical conductivity from 7.42 × 10-5 (CP1) to 1.20 × 10-4 S m-1 ([CP1 + Pd2+]). Upon light irradiation, the electrical conductivities are enhanced to 1.45 × 10-4 S m-1 (CP1) and 3.81 × 10-4 S m-1 ([CP1 + Pd2+]); which validates the highly desired photoresponsive device applications. Therefore, such type of materials may serve as SDG-army (sustainable development goal) to battle against the environmental issues and energy crisis.
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Affiliation(s)
- Suprava Bhunia
- Department of Chemistry, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Dipankar Sahoo
- Department of Physics, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Suvendu Maity
- Department of Chemistry, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Basudeb Dutta
- Department of Chemistry, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Satyabrata Bera
- Indian Association for the Cultivation of Science, Kolkata 700032, West Bengal, India
| | - Nabin Baran Manik
- Department of Physics, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Chittaranjan Sinha
- Department of Chemistry, Jadavpur University, Kolkata 700032, West Bengal, India
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2
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Stipurin S, Strassner T. Phosphorescent Bimetallic C^C* Platinum(
ii
) Complexes with Bridging Substituted Diphenylformamidinates. Chemistry 2022; 28:e202202227. [PMID: 36284471 PMCID: PMC10092827 DOI: 10.1002/chem.202202227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Indexed: 11/05/2022]
Abstract
A series of phosphorescent bimetallic platinum(II) complexes is presented, which were synthesized by the combination of bidentate cyclometalated N-heterocyclic carbene ligands and different bridging diphenylformamidinates. The complexes were characterized by standard techniques and additionally two solid-state structures could be obtained. Photoluminescence measurements revealed the strong emissive behavior of the compounds with quantum yields of up to 90 % and emission lifetimes of approx. 2 μs. The effect of the substitution pattern in the bridging ligands on the structural and photophysical properties of the complexes was examined in detail and rationalized by density functional theory calculations (PBE0/6-311G*).
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Affiliation(s)
- Sergej Stipurin
- Physikalische Organische Chemie Technische Universität Dresden 01069 Dresden Germany
| | - Thomas Strassner
- Physikalische Organische Chemie Technische Universität Dresden 01069 Dresden Germany
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3
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Pinter P, Soellner J, Strassner T. Metallophilic Interactions in Bimetallic Cyclometalated Platinum(II) N‐Heterocyclic Carbene Complexes. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100456] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Piermaria Pinter
- Physikalische Organische Chemie Technische Universität Dresden 01069 Dresden Germany
| | - Johannes Soellner
- Physikalische Organische Chemie Technische Universität Dresden 01069 Dresden Germany
| | - Thomas Strassner
- Physikalische Organische Chemie Technische Universität Dresden 01069 Dresden Germany
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4
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Ojha R, Mason D, Forsyth CM, Deacon GB, Junk PC, Bond AM. Diverse and unexpected outcomes from oxidation of the platinum(II) anticancer agent [Pt{(p-BrC 6F 4)NCH 2CH 2NEt 2}Cl(py)] by hydrogen peroxide. J Inorg Biochem 2021; 218:111360. [PMID: 33711633 DOI: 10.1016/j.jinorgbio.2021.111360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 01/17/2021] [Accepted: 01/17/2021] [Indexed: 12/18/2022]
Abstract
Oxidation of the anti-tumour agent [Pt{(p-BrC6F4)NCH2CH2NEt2}Cl(py)], 1 (py = pyridine) with hydrogen peroxide under a variety of conditions yields a range of organoenamineamidoplatinum(II) compounds [Pt{(p-BrC6F4)NCH=C(X)NEt2}Cl(py)] (X = H, Cl, Br) as well as species with shared occupancy involving H, Cl and Br. Thus, oxidation of the -CH2-CH2- backbone (dehydrogenation) occurs, often accompanied by substitution. Oxidation of 1 with H2O2 in acetone yielded 1:1 co-crystallized [Pt{(p-BrC6F4)NCH=CHNEt2}Cl(py)], 1H and [Pt{(p-BrC6F4)NCH=C(Cl)NEt2}Cl(py)], 1Cl. The former was obtained pure in low yield from the oxidation of 1 with (NH4)2[Ce(NO3)6] in acetone, and the latter was obtained from 1 and H2O2 in CH2Cl2 at near reflux. From the latter reaction under vigorous refluxing [Pt{(p-BrC6F4)NCH=C(Br)NEt2}Cl(py)], 1Br was isolated. In refluxing acetonitrile, oxidation of 1 with H2O2 yielded [Pt{(p-BrC6F4)NCH=C(H0.25Br0.75)NEt2}Cl(py)], 1H0.25Br0.75, in which the alkene is mainly substituted by Br in a dual occupancy. Treatment of 1 with H2O2 and tetrabutylammonium hydroxide in acetone at room temperature formed [Pt{(p-HC6F4)NCH2CH2NEt2}Cl(py)], 2. Oxidation of [Pt{(p-HC6F4)NCH2CH2NEt2}Br(py)], 3 with H2O2 in boiling acetonitrile gave the ligand oxidation product [Pt{(p-HC6F4)NCH=C(Br)NEt2}Br(py)], 3Br. All major products were identified by X-ray crystallography as well as by 1H and 19F NMR spectra. In cases of mixed crystals or dual occupancy compounds, the 19F and 1H NMR spectra showed dissociation into the components in the solution in the same proportions as in isolated crystalline material.
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Affiliation(s)
- Ruchika Ojha
- School of Chemistry, Monash University, Clayton 3800, VIC, Australia
| | - Dayna Mason
- School of Chemistry, Monash University, Clayton 3800, VIC, Australia
| | - Craig M Forsyth
- School of Chemistry, Monash University, Clayton 3800, VIC, Australia
| | - Glen B Deacon
- School of Chemistry, Monash University, Clayton 3800, VIC, Australia.
| | - Peter C Junk
- College of Science & Engineering, James Cook University, Townsville, Qld 4811, Australia.
| | - Alan M Bond
- School of Chemistry, Monash University, Clayton 3800, VIC, Australia.
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5
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Ricciardi L, Guzzi R, Rizzuti B, Ionescu A, Aiello I, Ghedini M, La Deda M. Anionic versus neutral Pt (II) complexes: The relevance of the charge for human serum albumin binding. J Inorg Biochem 2020; 206:111024. [PMID: 32070915 DOI: 10.1016/j.jinorgbio.2020.111024] [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: 11/29/2019] [Revised: 01/30/2020] [Accepted: 02/09/2020] [Indexed: 10/25/2022]
Abstract
The focus of this work is pointing out the different behavior of two structurally related Pt(II) complexes, the anionic cyclometalated NBu4[(Bzq)Pt(Thio)], 1 and the neutral [(Phen)Pt(Thio)], 2, (Bzq = benzo[h]quinoline, Phen = 1,10-phenantroline, Thio = 1,2-benzenedithiolate), on the interaction with human serum albumin (HSA), a key drug-delivery protein in the bloodstream. Being very limited the number of anionic Pt(II) complexes reported to date, this is a pioneering example of report on a protein-ligand interaction involving a negatively charged platinum compound. The study was carried out by using fluorescence spectroscopy, differential scanning calorimetry and molecular docking simulations. The results revealed a strong binding affinity between the anionic compound and the protein, whereas a weak/moderate binding interaction was highlighted for the neutral one. Comparative studies with site specific ligands (warfarin and ibuprofen), allowed us to identify the protein binding sites of the two compounds. The work aims to shed light on the relevance of the charge in designing new drugs with a favorable binding affinity for HSA, which strongly contributes to influence their pharmacological and toxicological profile.
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Affiliation(s)
- Loredana Ricciardi
- CNR NANOTEC - Institute of Nanotechnology, UOS Cosenza, 87036 Arcavacata di Rende, CS, Italy.
| | - Rita Guzzi
- CNR NANOTEC - Institute of Nanotechnology, UOS Cosenza, 87036 Arcavacata di Rende, CS, Italy; Department of Physics, University of Calabria, 87036 Arcavacata di Rende, CS, Italy
| | - Bruno Rizzuti
- CNR NANOTEC - Institute of Nanotechnology, UOS Cosenza, 87036 Arcavacata di Rende, CS, Italy
| | - Andreea Ionescu
- MAT_InLAB, Department of Chemistry and Chemical Technology, University of Calabria, 87036 Arcavacata di Rende, CS, Italy
| | - Iolinda Aiello
- CNR NANOTEC - Institute of Nanotechnology, UOS Cosenza, 87036 Arcavacata di Rende, CS, Italy; MAT_InLAB, Department of Chemistry and Chemical Technology, University of Calabria, 87036 Arcavacata di Rende, CS, Italy
| | - Mauro Ghedini
- CNR NANOTEC - Institute of Nanotechnology, UOS Cosenza, 87036 Arcavacata di Rende, CS, Italy; MAT_InLAB, Department of Chemistry and Chemical Technology, University of Calabria, 87036 Arcavacata di Rende, CS, Italy
| | - Massimo La Deda
- CNR NANOTEC - Institute of Nanotechnology, UOS Cosenza, 87036 Arcavacata di Rende, CS, Italy; MAT_InLAB, Department of Chemistry and Chemical Technology, University of Calabria, 87036 Arcavacata di Rende, CS, Italy.
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6
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Platinum(II)-azoimidazole drugs against TB and cancer: Structural studies, cytotoxicity and anti-mycobacterial activity. Polyhedron 2018. [DOI: 10.1016/j.poly.2018.05.062] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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7
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Yoshizawa A, Feula A, Leach AG, Male L, Fossey JS. Palladium and Platinum 2,4- cis-amino Azetidine and Related Complexes. Front Chem 2018; 6:211. [PMID: 29977888 PMCID: PMC6021532 DOI: 10.3389/fchem.2018.00211] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 05/23/2018] [Indexed: 11/13/2022] Open
Abstract
Seven N,N'-palladium(II) chloride complexes, one N,N'-palladium(II) acetate complex of 2,4-cis-azetidines where prepared and analyzed by single crystal XRD. Two platinum(II) chloride N,N'-complexes of 2,4-cis-azetidines where prepared and analyzed by single crystal XRD. Computational analysis and determination of the %Vbur was examined conducted. A CNN' metallocyclic complex was prepared by oxidative addition of palladium(0) to an ortho bromo 2,4-cis-disubstituted azetidine and its crystal structure displays a slightly pyramidalized metal-ligand orientation.
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Affiliation(s)
- Akina Yoshizawa
- School of Chemistry, University of Birmingham, Birmingham, United Kingdom
| | - Antonio Feula
- School of Chemistry, University of Birmingham, Birmingham, United Kingdom
| | - Andrew G. Leach
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Louise Male
- X-Ray Crystallography Facility, School of Chemistry, University of Birmingham, Birmingham, United Kingdom
| | - John S. Fossey
- School of Chemistry, University of Birmingham, Birmingham, United Kingdom
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8
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Tskhovrebov AG, Vasileva AA, Goddard R, Riedel T, Dyson PJ, Mikhaylov VN, Serebryanskaya TV, Sorokoumov VN, Haukka M. Palladium(II)-Stabilized Pyridine-2-Diazotates: Synthesis, Structural Characterization, and Cytotoxicity Studies. Inorg Chem 2018; 57:930-934. [PMID: 29356518 DOI: 10.1021/acs.inorgchem.8b00072] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Well-defined diazotates are scarce. Here we report the synthesis of unprecedented homoleptic palladium(II) diazotate complexes. The palladium(II)-mediated nitrosylation of 2-aminopyridines with NaNO2 results in the formation of metal-stabilized diazotates, which were found to be cytotoxic to human ovarian cancer cells.
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Affiliation(s)
- Alexander G Tskhovrebov
- St. Petersburg State University , Universitetskaya Nab. 7/9, St. Petersburg, Russian Federation.,Max-Planck-Institut für Kohlenforschung , D-45470 Mülheim/Ruhr, Germany
| | - Anna A Vasileva
- St. Petersburg State University , Universitetskaya Nab. 7/9, St. Petersburg, Russian Federation
| | - Richard Goddard
- Max-Planck-Institut für Kohlenforschung , D-45470 Mülheim/Ruhr, Germany
| | - Tina Riedel
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne , CH-1015 Lausanne, Switzerland
| | - Paul J Dyson
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne , CH-1015 Lausanne, Switzerland
| | - Vladimir N Mikhaylov
- St. Petersburg State University , Universitetskaya Nab. 7/9, St. Petersburg, Russian Federation
| | - Tatiyana V Serebryanskaya
- Research Institute for Physical Chemical Problems of the Belarusian State University, 14, Leningradskaya Str., 220030 Minsk, Belarus
| | - Viktor N Sorokoumov
- St. Petersburg State University , Universitetskaya Nab. 7/9, St. Petersburg, Russian Federation
| | - Matti Haukka
- Department of Chemistry, University of Jyväskylä , P.O. Box 35, FI-40014 Jyväskylä, Finland
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9
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Gavrish SP, Lampeka YD, Babak MV, Arion VB. Palladium Complexes of N,N'-Bis(2-aminoethyl)oxamide (H 2L): Structural (Pd IIL, Pd II2L 2, and Pd IVLCl 2), Electrochemical, Dynamic 1H NMR, and Cytotoxicity Studies. Inorg Chem 2018; 57:1288-1297. [PMID: 29308884 DOI: 10.1021/acs.inorgchem.7b02732] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The monomeric (PdL·2H2O) and dimeric (Pd2L2·7H2O) palladium(II) complexes of N,N'-bis(2-aminoethyl)oxamide (H2L) were isolated, and their structures were established by single-crystal X-ray diffraction. Both compounds display identical cis-(2Namide + 2Namine) coordination environments of the metal ion. The dimer, representing a combination of two PdL species with an open lateral chelate ring, has an "open clamshell"-like structure. The intramolecular metal-metal separation in Pd2L2 (3.215 Å) is slightly shorter than the sum of the van der Waals radii of the palladium(II) atoms. The dimeric complex is relatively stable to dissociation, and its spectral features in aqueous solutions have been compared to those of the monomeric complex. A 1H NMR spectroscopic study revealed the presence of the dynamic conformational exchange process assigned to a turning of the dimeric molecule "inside out" with an activation energy of 65 kJ/mol. Cyclic voltammetry of PdL in perchlorate-, chloride-, and sulfate-containing electrolytes revealed two-electron oxidation of the palladium center. For the dimeric complex similar, though irreversible, oxidation to the palladium(IV) state was observed in NaCl electrolyte. At the same time, in NaClO4 or Na2SO4 solutions oxidation of Pd2L2 occurs in two distinct steps. The first step is quasi-reversible and can be assigned to the formation of species in an intermediate PdIIIPdIII state. Monomeric palladium(IV) complex PdIVLCl2 was generated via chemical oxidation of PdIIL by peroxodisulfate in the presence of chloride ions and structurally characterized. The related MIIL complexes (M = Pd, Ni, Cu) showed low cytotoxicity in human cancer cell lines AGS (gastric adenocarcinoma) and HCT116 (colorectal carcinoma) with IC50 values from 204 to 525 μM, while the proligand H2L was devoid of antiproliferative activity (IC50 > 1000 μM).
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Affiliation(s)
- Sergey P Gavrish
- L.V. Pisarzhevskii Institute of Physical Chemistry of the National Academy of Sciences of Ukraine , Prospekt Nauki 31, Kyiv 03028, Ukraine
| | - Yaroslaw D Lampeka
- L.V. Pisarzhevskii Institute of Physical Chemistry of the National Academy of Sciences of Ukraine , Prospekt Nauki 31, Kyiv 03028, Ukraine
| | - Maria V Babak
- Department of Chemistry, National University of Singapore , 3 Science Drive 2, 117543 Singapore
| | - Vladimir B Arion
- Institute of Inorganic Chemistry, Faculty of Chemistry, University of Vienna , Währinger Straße 42, 1090 Vienna, Austria
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10
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Puls F, Richter N, Kataeva O, Knölker HJ. Synthesis of Tetranuclear Palladium(II) Complexes and Their Catalytic Activity for Cross-Coupling Reactions. Chemistry 2017; 23:17576-17583. [PMID: 28940427 DOI: 10.1002/chem.201703926] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Indexed: 01/24/2023]
Abstract
We have developed a short and simple synthesis of tetranuclear palladium(II) complexes that have been structurally confirmed by X-ray analysis. These complexes were formed in about 30 % overall yield by spontaneous metalation of dimethylaminoarene derivatives and exhibit a high stability. We have studied the utility of the tetranuclear palladium(II) complexes as precatalysts for Mizoroki-Heck and Suzuki-Miyaura cross-coupling reactions. Our novel complexes show excellent catalytic activities with high turnover numbers (TON) and high turnover frequencies (TOF) (e.g., for the Suzuki-Miyaura reaction: TON up to 538000 and TOF up to 23400 h-1 at room temperature).
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Affiliation(s)
- Florian Puls
- Department Chemie, Technische Universität Dresden, Bergstrasse 66, 01069, Dresden, Germany
| | - Nils Richter
- Department Chemie, Technische Universität Dresden, Bergstrasse 66, 01069, Dresden, Germany
| | - Olga Kataeva
- A. M. Butlerov Chemistry Institute, Kazan Federal University, Kremlevskaya Str. 18, Kazan, 420008, Russia
| | - Hans-Joachim Knölker
- Department Chemie, Technische Universität Dresden, Bergstrasse 66, 01069, Dresden, Germany
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11
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Ojha R, Junk PC, Deacon GB, Bond AM. A supramolecular approach to the examination of the structures of some anticancer organoamidoplatinum(II) complexes. Supramol Chem 2017. [DOI: 10.1080/10610278.2017.1405003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Ruchika Ojha
- School of Chemistry, Monash University, Clayton, Australia
| | - Peter C. Junk
- College of Science, Technology & Engineering, James Cook University, Townsville, Australia
| | - Glen B. Deacon
- School of Chemistry, Monash University, Clayton, Australia
| | - Alan M. Bond
- School of Chemistry, Monash University, Clayton, Australia
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12
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Lewis NA, Pakhomova S, Marzilli PA, Marzilli LG. Synthesis and Characterization of Pt(II) Complexes with Pyridyl Ligands: Elongated Octahedral Ion Pairs and Other Factors Influencing 1H NMR Spectra. Inorg Chem 2017; 56:9781-9793. [PMID: 28771331 DOI: 10.1021/acs.inorgchem.7b01294] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Our goal is to develop convenient methods for obtaining trans-[PtII(4-Xpy)2Cl2] complexes applicable to 4-substituted pyridines (4-Xpy) with limited volatility and water solubility, properties typical of 4-Xpy, with X being a moiety targeting drug delivery. Treatment of cis-[PtII(DMSO)2Cl2] (DMSO = dimethyl sulfoxide) with 4-Xpy in acetonitrile allowed isolation of a new series of simple trans-[PtII(4-Xpy)2Cl2] complexes. A side product with very downfield H2/6 signals led to our synthesis of a series of new [PtII(4-Xpy)4]Cl2 salts. For both series in CDCl3, the size of the H2/6 Δδ [coordinated minus "free" 4-Xpy H2/6 shift] decreased as 4-Xpy donor ability increased from 4-CNpy to 4-Me2Npy. This finding can be attributed to the greater synergistic reduction in the inductive effect of the Pt(II) center with increased 4-Xpy donor ability. The high solubility of [PtII(4-Xpy)4]Cl2 salts in CDCl3 (a solvent with low polarity) and the very downfield shift of the [PtII(4-Xpy)4]Cl2 H2/6 signals for the solutions provide evidence for the presence of strong {[PtII(4-Xpy)4]2+,2Cl-} ion pairs that are stabilized by multiple CH···Cl contacts. This conclusion gains considerable support from [PtII(4-Xpy)4]Cl2 crystal structures revealing that a chloride anion occupies a pseudoaxial position with nonbonding (py)C-H···Cl contacts (2.4-3.0 Å). Evidence for (py)C-H···Y contacts was obtained in NMR studies of [PtII(4-Xpy)4]Y2 salts with Y counterions less capable of forming H-bonds than chloride ion. Our synthetic approaches and spectroscopic analysis are clearly applicable to other nonvolatile ligands.
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Affiliation(s)
- Nerissa A Lewis
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Svetlana Pakhomova
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Patricia A Marzilli
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Luigi G Marzilli
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
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13
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Suffren Y, Kobayashi M, Ovens JS, Rodrigue-Witchel A, Genre C, Sakai K, Reber C, Leznoff DB. [Pt(SCN)4]2--Based Coordination Polymers and Supramolecular Squares: Intermolecular Pt···H-C Interactions Probed by Luminescence Spectroscopy at Variable Pressure. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201700149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yan Suffren
- Département de chimie; Université de Montréal; C.P. 6128 Succ. Centre-ville H3C 3J7 Montréal QC Canada
| | - Masayuki Kobayashi
- Department of Chemistry; Simon Fraser University; 8888 University Drive V5A 1S6 Burnaby, British Columbia Canada
- Department of Chemistry; Faculty of Science; Kyushu University; Motooka 744, Nishi-ku 819-0395 Fukuoka Japan
| | - Jeffrey S. Ovens
- Department of Chemistry; Simon Fraser University; 8888 University Drive V5A 1S6 Burnaby, British Columbia Canada
| | | | - Caroline Genre
- Département de chimie; Université de Montréal; C.P. 6128 Succ. Centre-ville H3C 3J7 Montréal QC Canada
| | - Ken Sakai
- Department of Chemistry; Faculty of Science; Kyushu University; Motooka 744, Nishi-ku 819-0395 Fukuoka Japan
| | - Christian Reber
- Département de chimie; Université de Montréal; C.P. 6128 Succ. Centre-ville H3C 3J7 Montréal QC Canada
| | - Daniel B. Leznoff
- Department of Chemistry; Simon Fraser University; 8888 University Drive V5A 1S6 Burnaby, British Columbia Canada
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14
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Hamasaka G, Muto T, Andoh Y, Fujimoto K, Kato K, Takata M, Okazaki S, Uozumi Y. Detailed Structural Analysis of a Self-Assembled Vesicular Amphiphilic NCN-Pincer Palladium Complex by Using Wide-Angle X-Ray Scattering and Molecular Dynamics Calculations. Chemistry 2017; 23:1291-1298. [PMID: 27739119 DOI: 10.1002/chem.201603494] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Indexed: 11/09/2022]
Abstract
Wide-angle X-ray scattering experiments and all-atomistic molecular dynamics calculations were performed to elucidate the detailed structure of bilayer vesicles constructed by self-assembly of an amphiphilic palladium NCN-pincer complex. We found an excellent agreement between the experimental and calculated X-ray spectra, and between the membrane thickness determined from a TEM image and that calculated from an electron-density profile, which indicated that the calculated structure was highly reliable. The analysis of the simulated bilayer structure showed that in general the membrane was softer than other phospholipid bilayer membranes. In this bilayer assemblage, the degree of alignment of complex molecules in the bilayer membrane was quite low. An analysis of the electron-density profile shows that the bilayer assemblage contains a space through which organic molecules can exit. Furthermore, the catalytically active center is near this space and is easily accessible by organic molecules, which permits the bilayer membrane to act as a nanoreactor. The free energy of permeation of water through the bilayer membrane of the amphiphilic complex was 12 kJ mol-1 , which is much lower than that for phospholipid bilayer membranes in general. Organic molecules are expected to pass though the bilayer membrane. The self-assembled vesicles were shown to be catalytically active in a Miyaura-Michael reaction in water.
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Affiliation(s)
- Go Hamasaka
- Institute for Molecular Science, Myodaiji, Okazaki, 444-8787, Japan.,SOKENDAI (The Graduate University for Advanced Studies), Myodaiji, Okazaki, 444-8787, Japan
| | - Tsubasa Muto
- Institute for Molecular Science, Myodaiji, Okazaki, 444-8787, Japan.,SOKENDAI (The Graduate University for Advanced Studies), Myodaiji, Okazaki, 444-8787, Japan
| | - Yoshimichi Andoh
- High-Performance Computation Section, Center for Computational Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Kazushi Fujimoto
- Department of Applied Chemistry, Faculty of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Kenichi Kato
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, 679-5148, Japan
| | - Masaki Takata
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, 679-5148, Japan
| | - Susumu Okazaki
- Department of Applied Chemistry, Faculty of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Yasuhiro Uozumi
- Institute for Molecular Science, Myodaiji, Okazaki, 444-8787, Japan.,SOKENDAI (The Graduate University for Advanced Studies), Myodaiji, Okazaki, 444-8787, Japan.,RIKEN Center for Sustainable Resource Science, Wako, 351-0198, Japan.,JST-CREST and JST-ACCEL, Myodaiji, Okazaki, 444-8787, Japan
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15
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Benedetti M, De Castro F, Fanizzi FP. Square-Planar PtIIversus Octahedral PtIVHalido Complexes:195Pt NMR Explained by a Simple Empirical Approach. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600573] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Michele Benedetti
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali; Università del Salento; Via Monteroni 73100 Lecce Italy
| | - Federica De Castro
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali; Università del Salento; Via Monteroni 73100 Lecce Italy
| | - Francesco P. Fanizzi
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali; Università del Salento; Via Monteroni 73100 Lecce Italy
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16
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A platinum-based hybrid drug design approach to circumvent acquired resistance to molecular targeted tyrosine kinase inhibitors. Sci Rep 2016; 6:25363. [PMID: 27150583 PMCID: PMC4858680 DOI: 10.1038/srep25363] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 04/15/2016] [Indexed: 12/13/2022] Open
Abstract
Three molecular targeted tyrosine kinase inhibitors (TKI) were conjugated to classical platinum-based drugs with an aim to circumvent TKI resistance, predominately mediated by the emergence of secondary mutations on oncogenic kinases. The hybrids were found to maintain specificity towards the same oncogenic kinases as the original TKI. Importantly, they are remarkably less affected by TKI resistance, presumably due to their unique structure and the observed dual mechanism of anticancer activity (kinase inhibition and DNA damage). The study is also the first to report the application of a hybrid drug approach to switch TKIs from being efflux transporter substrates into non-substrates. TKIs cannot penetrate into the brain for treating metastases because of efflux transporters at the blood brain barrier. The hybrids were found to escape drug efflux and they accumulate more than the original TKI in the brain in BALB/c mice. Further development of the hybrid compounds is warranted.
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Fung SK, Zou T, Cao B, Chen T, To WP, Yang C, Lok CN, Che CM. Luminescent platinum(II) complexes with functionalized N-heterocyclic carbene or diphosphine selectively probe mismatched and abasic DNA. Nat Commun 2016; 7:10655. [PMID: 26883164 PMCID: PMC4757794 DOI: 10.1038/ncomms10655] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 01/06/2016] [Indexed: 01/09/2023] Open
Abstract
The selective targeting of mismatched DNA overexpressed in cancer cells is an appealing strategy in designing cancer diagnosis and therapy protocols. Few luminescent probes that specifically detect intracellular mismatched DNA have been reported. Here we used Pt(II) complexes with luminescence sensitive to subtle changes in the local environment and report several Pt(II) complexes that selectively bind to and identify DNA mismatches. We evaluated the complexes' DNA-binding characteristics by ultraviolet/visible absorption titration, isothermal titration calorimetry, nuclear magnetic resonance and quantum mechanics/molecular mechanics calculations. These Pt(II) complexes show up to 15-fold higher emission intensities upon binding to mismatched DNA over matched DNA and can be utilized for both detecting DNA abasic sites and identifying cancer cells and human tissue samples with different levels of mismatch repair. Our work highlights the potential of luminescent Pt(II) complexes to differentiate between normal cells and cancer cells which generally possess more aberrant DNA structures. DNA pairing defects such as mismatched and abasic DNA are prevalent in cancer cells. Here, the authors present luminescent platinum based probes capable of preferentially binding to mismatched and abasic DNA, and reporting this by a significant luminescence enhancement
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Affiliation(s)
- Sin Ki Fung
- State Key Laboratory of Synthetic Chemistry, Institute of Molecular Functional Materials, Chemical Biology Centre, and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Taotao Zou
- State Key Laboratory of Synthetic Chemistry, Institute of Molecular Functional Materials, Chemical Biology Centre, and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China.,HKU Shenzhen Institute of Research and Innovation Shenzhen, Shenzhen 518053, China
| | - Bei Cao
- State Key Laboratory of Synthetic Chemistry, Institute of Molecular Functional Materials, Chemical Biology Centre, and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Tianfeng Chen
- Department of Chemistry, Jinan University, Guangzhou 510632, China
| | - Wai-Pong To
- State Key Laboratory of Synthetic Chemistry, Institute of Molecular Functional Materials, Chemical Biology Centre, and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Chen Yang
- State Key Laboratory of Synthetic Chemistry, Institute of Molecular Functional Materials, Chemical Biology Centre, and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China.,HKU Shenzhen Institute of Research and Innovation Shenzhen, Shenzhen 518053, China
| | - Chun-Nam Lok
- State Key Laboratory of Synthetic Chemistry, Institute of Molecular Functional Materials, Chemical Biology Centre, and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Chi-Ming Che
- State Key Laboratory of Synthetic Chemistry, Institute of Molecular Functional Materials, Chemical Biology Centre, and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China.,HKU Shenzhen Institute of Research and Innovation Shenzhen, Shenzhen 518053, China
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18
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Sayın E, Kürkçüoğlu GS, Yeşilel OZ, Hökelek T. Syntheses, crystal structures and spectroscopic properties of copper(II)–tetracyanometallate(II) complexes with nicotinamide and isonicotinamide ligands. J Mol Struct 2015. [DOI: 10.1016/j.molstruc.2015.04.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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González-Montiel S, Martínez-Otero D, Andrade-López N, Alvarado-Rodríguez JG, Carmona-Pichardo M, Cruz-Borbolla J, Pandiyan T, Pineda LW. Experimental and theoretical studies of C–H⋯M interactions in palladium and platinum complexes derived from 1,2-bis-(2-hydroxymethylphenylthio)ethane. Polyhedron 2015. [DOI: 10.1016/j.poly.2014.11.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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20
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Momeni BZ, Fathi N, Mohagheghi A. Easy oxidative addition of the carbon–halogen bond by dimethylplatinum(II) complexes containing a related series of diimine ligands: Synthesis, spectral characterization and crystal structure. J Mol Struct 2015. [DOI: 10.1016/j.molstruc.2014.09.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Sayın E, Kürkçüoğlu GS, Yeşilel OZ, Hökelek T. CH⋯Pd interactions: one dimensional heteropolynuclear complexes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 132:803-814. [PMID: 24975519 DOI: 10.1016/j.saa.2014.05.094] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/13/2014] [Accepted: 05/22/2014] [Indexed: 06/03/2023]
Abstract
Three cyanide complexes, [Cu(hepH)2Pd(μ-CN)2(CN)2]n (1), [Zn(hepH)2Pd(μ-CN)2(CN)2]n (2) and [Cd(hepH)2Pd(μ-CN)2(CN)2]n (3) (2-pyridineethanol abbreviated to hepH), have been synthesized and characterized by various techniques (elemental analysis, FT-IR and Raman spectroscopy, thermal analysis and single crystal X-ray diffraction). FT-IR spectroscopy pointed out the existence of terminal and bridged cyanide ligands in the complexes. The crystallographic analyses reveal that complexes 1 and 2 crystallize in the triclinic system, space group P-1 and complex 3 crystallizes in the monoclinic system, space group P2₁/n. The palladium atom is coordinated with cyanide-carbon atoms in a square-planar arrangement and the metal(II) atoms are six-coordinated with two cyanide nitrogen, two hepH nitrogen and two hepH oxygen atoms, in a distorted octahedral arrangement. In all the complexes adjacent chains are connected by CH⋯Pd, π⋯π and OH⋯N hydrogen bonding interactions to form two- and three-dimensional networks. When it comes to thermal analysis, the complexes followed usual decomposition mechanism in which neutral ligands (hepH) are released first, and then cyanide ligands are decomposed. The final decomposition products are found to be the corresponding metal oxides.
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Affiliation(s)
- Elvan Sayın
- Eskişehir Osmangazi University, The Institute of Science, Department of Physics, TR-26480 Eskişehir, Turkey
| | - Güneş Süheyla Kürkçüoğlu
- Eskişehir Osmangazi University, Faculty of Arts and Sciences, Department of Physics, TR-26480 Eskişehir, Turkey.
| | - Okan Zafer Yeşilel
- Eskişehir Osmangazi University, Faculty of Arts and Sciences, Department of Chemistry, TR-26480 Eskişehir, Turkey
| | - Tuncer Hökelek
- Hacettepe University, Faculty of Engineering, Department of Physics, TR-06800 Beytepe Ankara, Turkey
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22
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Syntheses, crystal structures, spectroscopic and thermal analyses of 3- and 4-aminomethylpyridinium tetracyanometallate(II) complexes. Inorganica Chim Acta 2013. [DOI: 10.1016/j.ica.2013.06.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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23
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Hamamci Alisir S, Demir S, Topcu Y, Yang SY. A highly fluorescent dinuclear silver(I) complex of pyrazine derivatives: Combined experimental and DFT/TD-DFT investigations. Polyhedron 2013. [DOI: 10.1016/j.poly.2013.03.061] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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24
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Chval Z, Kabeláč M, Burda JV. Mechanism of the cis-[Pt(1R,2R-DACH)(H2O)2]2+ intrastrand binding to the double-stranded (pGpG)·(CpC) dinucleotide in aqueous solution: a computational DFT study. Inorg Chem 2013; 52:5801-13. [PMID: 23656523 DOI: 10.1021/ic302654s] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A mechanism of the intrastrand 1,2-cross-link formation between the double-stranded pGpG·CpC dinucleotide (ds(pGpG)) and fully aquated oxaliplatin cis-[Pt(DACH)(H2O)2](2+) (DACH = cyclohexane-1R,2R-diamine) is presented. All structures of the reaction pathways including the transition states (TSs) were fully optimized in water solvent using DFT methodology with dispersion corrections. Both 5' → 3' and 3' → 5' binding directions were considered. In the first step there is a slight kinetic preference for 5'-guanine (5'G) monoadduct formation with an activation Gibbs free energy of 18.7 kcal/mol since the N7 center of the 5'G base is fully exposed to the solvent. On the other hand, the N7 atom of 3'-guanine (3'G) is sterically shielded by 5'G. The lowest energy path for formation of the 3'G monoadduct with an activation barrier of 19.3 kcal/mol is connected with a disruption of the 'DNA-like' structure of ds(pGpG). Monoadduct formation is the rate-determining process. The second step, chelate formation, is kinetically preferred in the 3' → 5' direction. The whole process of the platination is exergonic by up to -18.8 kcal/mol. Structural changes of ds(pGpG), charge transfer effects, and the influence of platination on the G·C base pair interaction strengths are also discussed in detail.
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Affiliation(s)
- Zdeněk Chval
- Department of Laboratory Methods and Information Systems, Faculty of Health and Social Studies, University of South Bohemia, J. Boreckého 27, 370 11 České Budějovice, Czech Republic.
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25
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Two dimensional heteropolynuclear Zn(II) and Cd(II)-tetracyanopalladate(II) complexes with the 1-ethylimidazole ligand exhibiting C–H⋯Pd interactions. Polyhedron 2013. [DOI: 10.1016/j.poly.2013.02.047] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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26
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Elder RM, Jayaraman A. Role of structure and dynamics of DNA with cisplatin and oxaliplatin adducts in various sequence contexts on binding of HMGB1a. MOLECULAR SIMULATION 2012. [DOI: 10.1080/08927022.2011.654208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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27
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Elder R, Jayaraman A. Sequence-specific recognition of cancer drug-DNA adducts by HMGB1a repair protein. Biophys J 2012; 102:2331-8. [PMID: 22677386 PMCID: PMC3353062 DOI: 10.1016/j.bpj.2012.04.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 04/05/2012] [Accepted: 04/09/2012] [Indexed: 01/16/2023] Open
Abstract
The efficacy of cancer drugs such as cisplatin (Cp) and oxaliplatin (Ox), which covalently bind to DNA to form drug-DNA adducts, is linked to their recognition by repair proteins such as HMGB1a. Previous experimental studies showed that HMGB1a's binding affinity for Cp- and Ox-DNA varies with the drug used and the local DNA sequence context of the adduct. We link this differential binding affinity to the free energy of deforming (bending and minor groove opening) the drug-DNA molecule during HMGB1a binding. Specifically, the minimal binding affinity of HMGB1a for Ox-DNA in the TGGA context is explained by its larger deformation free energy compared with Cp-DNA or Ox-DNA in other sequence contexts. Methyl groups on neighboring thymine bases in Ox-TGGA crowd the minor groove and sterically hinder the motion of the diaminocyclohexane ring of Ox, leading to this reduced deformability and resultant decrease in HMGB1a's binding affinity.
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Affiliation(s)
| | - Arthi Jayaraman
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado
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28
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Chatterjee S, Krause JA, Madduma-Liyanage K, Connick WB. Platinum(II) Diimine Complexes with Halide/Pseudohalide Ligands and Dangling Trialkylamine or Ammonium Groups. Inorg Chem 2012; 51:4572-87. [DOI: 10.1021/ic202462a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sayandev Chatterjee
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati,
Ohio 45221-0172, United States
| | - Jeanette A. Krause
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati,
Ohio 45221-0172, United States
| | - Kumudu Madduma-Liyanage
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati,
Ohio 45221-0172, United States
| | - William B. Connick
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati,
Ohio 45221-0172, United States
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30
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Yeşilel OZ, Günay G, Darcan C, Soylu MS, Keskin S, Ng SW. An unusual 3D metal–organic framework, {[Ag4(μ4-pzdc)2(μ-en)2]·H2O}n: C–H⋯Ag, N–H⋯Ag and (O–H)⋯Ag interactions and an unprecedented coordination mode for pyrazine-2,3-dicarboxylate. CrystEngComm 2012. [DOI: 10.1039/c2ce06603c] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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31
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32
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Blasberg F, Bolte M, Wagner M, Lerner HW. Chemical behavior of ortho-hydroquinone-based bis(pyrazol-1-yl)methane ligands in the presence of palladium(II) chloride. J Organomet Chem 2011. [DOI: 10.1016/j.jorganchem.2011.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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33
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Jamali S, Milić D, Kia R, Mazloomi Z, Abdolahi H. Organoplatinum(ii) complexes containing chelating or bridging bis(N-heterocyclic carbene) ligands: formation of a platinum(ii) carbonate complex by aerial CO2 fixation. Dalton Trans 2011; 40:9362-5. [DOI: 10.1039/c1dt10736d] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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34
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Wilson JJ, Fedoce Lopes J, Lippard SJ. Synthesis, characterization, and photophysical properties of three platinum(II) complexes bearing fluorescent analogues of the Di-2-pyridylmethane ligand. Inorg Chem 2010; 49:5303-15. [PMID: 20423108 DOI: 10.1021/ic100411p] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three new ligands of the general formula [RNHCH(py)(2)] (py = pyridine; R = tosyl, Ts-dpm; R = dansyl, Ds-dpm; R = 7-nitro-1,2,3-benzoxadiazole, NBD-dpm) have been synthesized and characterized. Reactions of these ligands with cis-[Pt(DMSO)(2)Cl(2)] (DMSO = dimethyl sulfoxide) in methanol affords [Pt(Ts-dpm)Cl(2)] (1), [Pt(Ds-dpm)Cl(2)] (2), and [Pt(NBD-dpm)Cl(2)] (3). The crystal structures of these complexes reveal bidentate coordination of the ligands to the Pt center with nonplanar chelate rings. Because of inequivalent substituents on the methine carbon atom of the ligands, distinct exo and endo isomers exist in the three complexes. X-ray analyses indicate that 1 crystallizes in the endo conformation, 2 in the exo conformation, and 3 as a mixture of the two conformers. The (1)H NMR and (195)Pt NMR spectra of the complexes display two sets of independent signals corresponding to the chemically inequivalent exo and endo conformers. The exo conformer was determined by 2D NMR spectroscopy to be thermodynamically favored for all three complexes. Density functional theory (DFT), time-dependent DFT, and atoms in molecules calculations were carried out for both conformers of 3 to investigate differences in their electronic structures and to explore intramolecular interactions. In the presence of dioxygen, 1 thermally decomposes at 60 degrees C to form several unidentified products. Compound 2 is thermally stable even in the presence of dioxygen and water but upon light exposure decomposes to form a new platinum(II) species with a (195)Pt NMR shift of -2177 ppm. Compound 3 reacts both thermally and photochemically in the presence of dioxygen and trace amounts of water to form both 4-amino-7-nitro-2,1,3-benzoxadiazole and [Pt(dpk)Cl(2)] (dpk = di-2-pyridyl ketone). Oxidation of 1 and 3 with H(2)O(2) in acetic acid affords a mixture of compounds, two of which contain dpm ligands bound in a tridentate manner to platinum.
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Affiliation(s)
- Justin J Wilson
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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35
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Yeguas V, Campomanes P, López R, Díaz N, Suárez D. Understanding Regioselective Cleavage in Peptide Hydrolysis by a Palladium(II) Aqua Complex: A Theoretical Point of View. J Phys Chem B 2010; 114:8525-35. [DOI: 10.1021/jp101870j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Violeta Yeguas
- Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería, 8, 33006 Oviedo, Spain, and Laboratory of Computational Chemistry and Biochemistry, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Pablo Campomanes
- Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería, 8, 33006 Oviedo, Spain, and Laboratory of Computational Chemistry and Biochemistry, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Ramón López
- Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería, 8, 33006 Oviedo, Spain, and Laboratory of Computational Chemistry and Biochemistry, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Natalia Díaz
- Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería, 8, 33006 Oviedo, Spain, and Laboratory of Computational Chemistry and Biochemistry, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Dimas Suárez
- Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería, 8, 33006 Oviedo, Spain, and Laboratory of Computational Chemistry and Biochemistry, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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36
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Mishur RJ, Zheng C, Gilbert TM, Bose RN. Synthesis, X-ray crystallographic, and NMR characterizations of platinum(II) and platinum(IV) pyrophosphato complexes. Inorg Chem 2008; 47:7972-82. [PMID: 18693681 DOI: 10.1021/ic800237a] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A series of mononuclear cis-diamineplatinum(II) pyrophosphato complexes containing ammine (am), trans-1,2-cyclohexanediamine (dach), and 1,2-ethanediamine (en) as the amine ligands were synthesized and characterized by (31)P and (195)Pt NMR spectroscopy. Chemical shifts of (31)P NMR resonances of these completely deprotonated complexes appear at 2.12, 1.78, and 1.93 ppm, indicating a coordination chemical shift of at least 8 ppm. The (195)Pt NMR chemical shifts for the am and dach complexes were observed at -1503 and -1729 ppm. The complexes are highly stable at neutral pH; no aquation due to the release of either phosphate or amine ligands was observed within 48 h. Furthermore, no partial deligation of the pyrophosphate ligand was detected within several days at neutral pH. At lower pH, however, release of a pyrophosphate ion was observed with concomitant formation of a bridged pyrophosphatoplatinum(II) dinuclear complex. The extended crystal structure containing the dach ligand revealed a zigzag chain stacked in a head-to-tail fashion. Moreover, two zigzag chains are juxtaposed in a parallel fashion and supported by additional hydrogen bonds reminiscent of DNA structures where two strands of DNA bases are held by hydrogen bonds. Theoretical calculations support the notion that the two dinuclear units are held together primarily by hydrogen bonds between the amine and phosphate moieties. Platinum(II) pyrophosphato complexes were readily oxidized by hydrogen peroxide to yield cis-diamine-trans-dihydroxopyrophosphatoplatinum(IV) complexes. Two of these complexes, containing am and en, were characterized by X-ray crystallography. Notable structural features include Pt-O (phosphate) bond distances of 2.021-2.086 A and departures from 180 degrees in trans-HO-Pt-OH bond angles, >90 degrees in O-Pt-O, and >90 degrees in cis-N-Pt-N bond angles. The departure in the trans-HO-Pt-OH angle is more pronounced in the 1,2-ethanediamine complex compared to the dach analogue because of the existence of two molecules possessing enantiomeric conformations within the asymmetric unit. (31)P NMR spectra exhibited well-resolved (195)Pt satellites with coupling constants of 15.4 Hz for the ammine and 25.9 Hz for both the 1,2-ethanediamine and trans-1,2-cyclohexanediamine complexes. The (195)Pt NMR spectrum of the ammine complex clearly showed coupling with two equivalent N atoms.
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Affiliation(s)
- Robert J Mishur
- Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, USA
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37
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C–H⋯Pt(II) interaction-controlled self-assembly and photophysics of chiral bis(pyrrol-2-ylmethyleneamino)cyclohexane platinum(II) complexes. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.03.077] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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38
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39
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Kim M, Taylor TJ, Gabbaï FP. Hg(II)···Pd(II) Metallophilic Interactions. J Am Chem Soc 2008; 130:6332-3. [DOI: 10.1021/ja801626c] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mieock Kim
- Department of Chemistry, Texas A&M University, College Station, Texas 77843
| | - Thomas J. Taylor
- Department of Chemistry, Texas A&M University, College Station, Texas 77843
| | - François P. Gabbaï
- Department of Chemistry, Texas A&M University, College Station, Texas 77843
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Zhao SB, Liu GH, Song D, Wang S. Impact of the linker groups in bis(7-azaindol-1-yl) chelate ligands on structures and stability of Pt(N,N-L)R2 complexes. Dalton Trans 2008:6953-65. [DOI: 10.1039/b813501k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Janzen DE, VanDerveer DG, Mehne LF, da Silva Filho DA, Brédas JL, Grant GJ. Cyclometallated Pt(ii) and Pd(ii) complexes with a trithiacrown ligand. Dalton Trans 2008:1872-82. [DOI: 10.1039/b717910c] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Heckenroth M, Kluser E, Neels A, Albrecht M. Palladation of diimidazolium salts at the C4 position: access to remarkably electron-rich palladium(ii) centers. Dalton Trans 2008:6242-9. [DOI: 10.1039/b812405a] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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43
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Grant GJ, Biggers DA, Vanderveer DG. Contrasting arsine and phosphine coordination behaviour: heteroleptic palladium(II) complexes with triphenylarsine and a crown thioether. MAIN GROUP CHEMISTRY 2007. [DOI: 10.1080/10241220801927767] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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44
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Kemp S, Wheate NJ, Buck DP, Nikac M, Collins JG, Aldrich-Wright JR. The effect of ancillary ligand chirality and phenanthroline functional group substitution on the cytotoxicity of platinum(II)-based metallointercalators. J Inorg Biochem 2007; 101:1049-58. [PMID: 17544512 DOI: 10.1016/j.jinorgbio.2007.04.009] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Revised: 04/09/2007] [Accepted: 04/10/2007] [Indexed: 10/23/2022]
Abstract
Fifteen platinum(II)-based metallointercalators have been synthesised that utilise substituted 1,10-phenanthroline (phen) ligands, including 5-chloro-1,10-phenanthroline (5-Cl-phen), 5-methyl-1,10-phenanthroline (5-CH3-phen), 5-amino-1,10-phenanthroline (5-NH2-phen), 5-nitro-1,10-phenanthroline (5-NO2-phen) and dipyrido[3,2-d:2',3'-f]quinoxaline (dpq), and achiral ethylenediamine (en) and the chiral ancillary ligands 1S,2S-diaminocyclohexane (S,S-dach) and 1R,2R-diaminocyclohexane (R,R-dach). Their cytotoxicity in the L1210 murine leukaemia cell line was determined using growth inhibition assays. The most cytotoxic metal complexes are those that contain S,S-dach ancillary ligands and 5-CH3-phen intercalating ligands. One metallointercalator [Pt(5-CH3-phen)(S,S-dach)]Cl2 (5MESS), displays a 5-10-fold increase in cytotoxicity compared to the clinical agent cisplatin. From DNA binding experiments there appears to be no significant difference between any of the metal complexes, indicating that neither DNA binding affinity nor the mode of binding/DNA adduct formed is the sole determinant of the cytotoxicity of this family of platinum(II)-based metallointercalators.
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Affiliation(s)
- Sharon Kemp
- School of Biomedical and Health Sciences, University of Western Sydney, Locked Bag 1797, Penrith South DC, NSW 2560, Australia
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45
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Scaffidi-Domianello YY, Nazarov AA, Haukka M, Galanski MS, Keppler BK, Schneider J, Du P, Eisenberg R, Kukushkin VY. First Example of the Solid-State Thermal Cyclometalation of Ligated Benzophenone Imine Giving Novel Luminescent Platinum(II) Species. Inorg Chem 2007; 46:4469-82. [PMID: 17451237 DOI: 10.1021/ic062414k] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The (benzophenone imine)platinum(II) compounds trans-[PtCl2(Ph2C=NH)(RR'SO)] [R, R'=Me, Me (2); n-Pr, n-Pr (3); (CH2)4 (4); Me, Ph (5); Me, p-MeC6H4 (6)] were prepared by the reaction of Ph2C=NH with K[PtCl3(RR'SO)], obtained in situ from K2[PtCl4] and the corresponding sulfoxide, giving 2-6 as well as cis-[PtCl2(Ph2C=NH)2] (1) as a minor product. The complexes were characterized by 1H, 13C, and 195Pt NMR and IR spectroscopy, electrospray ionization mass spectrometry, and C, H, and N elemental analysis. The X-ray crystallography of 1 enables confirmation of the cis configuration of the complex, while in 2 and 4.1/2CHCl3, the imine and sulfoxide ligands are mutually trans. The solid-state structure of 4.1/2CHCl3 consists of two dimeric Pt moieties representing a rather weak Pt...Pt interaction. The dimeric architecture of 4.1/2CHCl3 is enhanced by the hydrogen bonding between imine H atoms and O atoms. The orthometalation of 1 and 2-6 proceeds both in the solid phase and in a toluene suspension, leading to the formation of [PtCl{Ph(C6H4)C=NH}(Ph2C=NH)] (7) and [PtCl{Ph(C6H4)C=NH}(RR'SO)] (8-12), respectively, isolated in nearly quantitative yields. Complexes 8-12 are emissive at room temperature both in solution (lambdaemmax approximately 535 nm) and in the solid state (lambdaemmax 560-610 nm), with excited-state lifetimes of ca. 300-600 ns, representing a new family of PtII-based luminescent complexes. Compounds 8 and 10 have been characterized by X-ray analysis, confirming the square-planar coordination geometry of the metal center with the almost planar platinacycles. In 8, the asymmetric unit contains two independent Pt molecules, while in 10, it includes four Pt molecules linked by the intermolecular hydrogen-bonding network between the NH group and Cl atoms.
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46
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Mukhopadhyay A, Pal S. Intramolecular Apical C–H···M Interactions in Square-Planar Nickel(II) Complexes with Dianionic Tridentate Ligands and 2-Phenylimidazole. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200600594] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Abhik Mukhopadhyay
- School of Chemistry, University of Hyderabad, Hyderabad 500 046, India, Fax: +91‐40‐2301‐2460
| | - Samudranil Pal
- School of Chemistry, University of Hyderabad, Hyderabad 500 046, India, Fax: +91‐40‐2301‐2460
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47
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Lopes JF, de A Menezes VS, Duarte HA, Rocha WR, De Almeida WB, Dos Santos HF. Monte Carlo Simulation of Cisplatin Molecule in Aqueous Solution. J Phys Chem B 2006; 110:12047-54. [PMID: 16800515 DOI: 10.1021/jp057448c] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The Lennard-Jones (12-6) parameters were obtained for all atoms of cisplatin molecule using the ab initio quantum mechanical potential energy surface for the water-cisplatin interaction as reference data. The parameters found were (epsilon/kcal.mol(-1) and sigma/angstroms) 1.0550, 3.6590 (Pt); 0.0381, 4.6272 (Cl); 0.0455, 3.3783 (N); and 0.0185, 0.0936 (H) and provided very good results for the description of the aqueous solution of cisplatin through Monte Carlo simulation. From statistical analysis of solute-solvent interactions, we observed that the NH3 groups are involved in 53% of the calculated hydrogen bonds with a significant contribution from chlorides (41%) and only 6% involving the Pt center. This is in agreement with the expected behavior for such molecules. Two hydration shells with 22 and 81 water molecules, respectively, centered around 4.6 and 7.3 angstroms were found from the center of mass pair correlation function analysis. The cisplatin atomic Lennard-Jones parameters are reported for the first time, and they might be useful for studying the structure, properties, and processes of cisplatin-like molecules in aqueous solution, including explicitly the solvent effect.
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Affiliation(s)
- Juliana Fedoce Lopes
- NEQC: Núcleo de Estudos em Química Computacional, Departamento de Química, ICE, Universidade Federal de Juiz de Fora, Campus Martelos, CEP 36036-900, Juiz de Fora, MG, Brazil
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48
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Shi P, Jiang Q, Lin J, Zhao Y, Lin L, Guo Z. Gold(III) compounds of 1,4,7-triazacyclononane showing high cytotoxicity against A-549 and HCT-116 tumor cell lines. J Inorg Biochem 2006; 100:939-45. [PMID: 16472862 DOI: 10.1016/j.jinorgbio.2005.12.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Revised: 12/10/2005] [Accepted: 12/16/2005] [Indexed: 10/25/2022]
Abstract
Two gold(III) compounds [Au(TACN)Cl(2)]Cl (1) and [Au(TACN)Cl(2)][AuCl(4)] (2) (where TACN=1,4,7-triazacyclononane), have been synthesized and characterized by electrospray ionization mass spectrometry (ESI-MS), (1)H NMR spectroscopy and elemental analyses. The structure of compound 2 was determined by X-ray crystallography, in which TACN coordinates to the gold(III) center in a bidentate mode and the unbound amine group forms a very short intramolecular Au-H(-N) contact (1.91A). Biological activity data showed that compound 1 is more cytotoxic than cisplatin against A-549 and HCT-116 tumor cell lines. The interactions of compound 1 with CT-DNA were studied by UV-Vis, fluorescence and CD spectroscopy, which suggests that compound 1 can induce the distortion of DNA double helix.
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Affiliation(s)
- Pengfei Shi
- State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, PR China
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49
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Albano V, Bandini M, Melucci M, Monari M, Piccinelli F, Tommasi S, Umani-Ronchi A. Novel Chiral Diamino-Oligothiophenes as Valuable Ligands in Pd-Catalyzed Allylic Alkylations. On the “Primary” Role of “Secondary” Interactions in Asymmetric Catalysis. Adv Synth Catal 2005. [DOI: 10.1002/adsc.200505109] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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50
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Malina J, Vojtiskova M, Brabec V, Diakos CI, Hambley TW. DNA adducts of the enantiomers of the Pt(II) complexes of the ahaz ligand (ahaz=3-aminohexahydroazepine) and recognition of these adducts by HMG domain proteins. Biochem Biophys Res Commun 2005; 332:1034-41. [PMID: 15922304 DOI: 10.1016/j.bbrc.2005.05.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2005] [Accepted: 05/10/2005] [Indexed: 11/22/2022]
Abstract
The bending, unwinding, and structural changes in DNA caused by the binding of each of the enantiomers of the platinum(II) complexes of the ahaz ligand (R- and S-[PtCl(2)(ahaz)], ahaz=3-aminohexahydroazepine) have been studied using 20-23 bp oligonucleotides containing TGGT and CGGA-binding sites as has the recognition of the adducts by HMG domain proteins. The domain A of HMGB1 (HMGB1a protein) binds to the adduct formed by the R enantiomer at the CGGA sequence with a similar high affinity as it does to the adduct of antitumor cisplatin, and to the adduct formed by the S enantiomer with a slightly lower affinity. In contrast, HMGB1a binds much more weakly to the ahaz adducts than to the cisplatin adducts formed at the TGGT sequence, with the binding to the adduct formed by the R enantiomer being weakest. Each enantiomer and cisplatin cause unwinding of both sequences that is in the narrow range, 19-22 degrees. There are modest but significant differences in the degree of bending induced, with the S enantiomer causing the least bending, cisplatin intermediate, and the R enantiomer the most. Molecular modeling of the {Pt(ahaz)}/GG adducts in 8-bp models reveals significant differences in the local distortion at the GG-binding sites depending on the flanking bases and shows that interactions between the thymine methyl groups and the ahaz ligand are likely to inhibit bending of the TGGT sequence.
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Affiliation(s)
- Jaroslav Malina
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, CZ-61265 Brno, Czech Republic
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