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Caković A, Ćoćić D, Živanović M, Janković N, Milivojević N, Delibašić M, Kostić M, Radojević I, Grujović M, Marković KG, Klisurić OR, Vraneš M, Bogojeski J. Enhancing Bioactivity of N,N,N-Chelating Rhodium(III) Complexes with Ionic Liquids: Toward Targeted Cancer Therapy. J Med Chem 2024. [PMID: 39058952 DOI: 10.1021/acs.jmedchem.4c01220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
This study investigates the potential of using ionic liquids as cosolvents to enhance the solubility and activity of poorly soluble rhodium(III) complexes, particularly those with diene, pyridine derivatives, and camphor-derived bis-pyrazolylpyridine ligands, in relation to 5'-GMP, CT-DNA, and HSA as well as their biological activity. Findings indicate that ionic liquids significantly increase the substitution activity of these complexes toward 5'-GMP while only marginally affecting DNA/HSA binding affinities with molecular docking, further confirming the experimental results. Lipophilicity assessments indicated good lipophilicity. Notably, cytotoxicity studies show that Rh2 is selectively effective against HeLa cancer cells, with IL1 and IL10 modulating the cytotoxic effects. Redox evaluations indicate that rhodium complexes induce oxidative stress in cancerous cells while maintaining redox balance in noncancerous cells. By elucidating the role of ionic liquids in modulating these effects, the study proposes a promising avenue for augmenting the efficacy and selectivity of cancer treatments, thus opening new horizons in cancer therapeutics.
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Affiliation(s)
- Angelina Caković
- University of Kragujevac, Faculty of Science, Radoja Domanovića 12, 34000 Kragujevac, Serbia
| | - Dušan Ćoćić
- University of Kragujevac, Faculty of Science, Radoja Domanovića 12, 34000 Kragujevac, Serbia
| | - Marko Živanović
- University of Kragujevac, Institute for Information Technologies Kragujevac, Department of Science, Jovana Cvijića bb, 34000 Kragujevac, Serbia
| | - Nenad Janković
- University of Kragujevac, Institute for Information Technologies Kragujevac, Department of Science, Jovana Cvijića bb, 34000 Kragujevac, Serbia
| | - Nevena Milivojević
- University of Kragujevac, Institute for Information Technologies Kragujevac, Department of Science, Jovana Cvijića bb, 34000 Kragujevac, Serbia
| | - Marija Delibašić
- University of Belgrade, Faculty of Biology, Center for Forensic and Applied Molecular Genetics, Studentski trg 16, 11000 Belgrade, Serbia
| | - Marina Kostić
- University of Kragujevac, Institute for Information Technologies Kragujevac, Department of Science, Jovana Cvijića bb, 34000 Kragujevac, Serbia
| | - Ivana Radojević
- University of Kragujevac, Faculty of Science, Radoja Domanovića 12, 34000 Kragujevac, Serbia
| | - Mirjana Grujović
- University of Kragujevac, Institute for Information Technologies Kragujevac, Department of Science, Jovana Cvijića bb, 34000 Kragujevac, Serbia
| | - Katarina G Marković
- University of Kragujevac, Institute for Information Technologies Kragujevac, Department of Science, Jovana Cvijića bb, 34000 Kragujevac, Serbia
| | - Olivera R Klisurić
- University of Novi Sad, Faculty of Sciences, Department of Physics, Trg Dositeja Obradovića 4, 21000 Novi Sad, Serbia
| | - Milan Vraneš
- University of Novi Sad, Faculty of Sciences, Department of Chemistry, Biochemistry and Environmental Protection, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia
| | - Jovana Bogojeski
- University of Kragujevac, Faculty of Science, Radoja Domanovića 12, 34000 Kragujevac, Serbia
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2
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Frota HF, Lorentino CMA, Barbosa PF, Ramos LS, Barcellos IC, Giovanini L, Souza LOP, Oliveira SSC, Abosede OO, Ogunlaja AS, Pereira MM, Branquinha MH, Santos ALS. Antifungal potential of the new copper(II)-theophylline/1,10-phenanthroline complex against drug-resistant Candida species. Biometals 2024; 37:321-336. [PMID: 37917351 DOI: 10.1007/s10534-023-00549-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 10/03/2023] [Indexed: 11/04/2023]
Abstract
Candida spp. are the commonest fungal pathogens worldwide. Antifungal resistance is a problem that has prompted the discovery of novel anti-Candida drugs. Herein, 25 compounds, some of them containing copper(II), cobalt(II) and manganese(II) ions, were initially evaluated for inhibiting the growth of reference strains of Candida albicans and Candida tropicalis. Eight (32%) of the compounds inhibited the proliferation of these yeasts, displaying minimum inhibitory concentrations (MICs) ranging from 31.25 to 250 μg/mL and minimum fungicidal concentration (MFCs) from 62.5 to 250 μg/mL. Drug-likeness/pharmacokinetic calculated by SwissADME indicated that the 8 selected compounds were suitable for use as topical drugs. The complex CTP, Cu(theo)2phen(H2O).5H2O (theo = theophylline; phen = 1,10-phenanthroline), was chosen for further testing against 10 medically relevant Candida species that were resistant to fluconazole/amphotericin B. CTP demonstrated a broad spectrum of action, inhibiting the growth of all 20 clinical fungal isolates, with MICs from 7.81 to 62.5 μg/mL and MFCs from 15.62 to 62.5 μg/mL. Conversely, CTP did not cause lysis in erythrocytes. The toxicity of CTP was evaluated in vivo using Galleria mellonella and Tenebrio molitor. CTP had no or low levels of toxicity at doses ranging from 31.25 to 250 μg/mL for 5 days. After 24 h of treatment, G. mellonella larvae exhibited high survival rates even when exposed to high doses of CTP (600 μg/mL), with the 50% cytotoxic concentration calculated as 776.2 μg/mL, generating selectivity indexes varying from 12.4 to 99.4 depending on each Candida species. These findings suggest that CTP could serve as a potential drug to treat infections caused by Candida species resistant to clinically available antifungals.
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Affiliation(s)
- Heloisa F Frota
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
- Programa de Pós-Graduação Em Bioquímica (PPGBq), Instituto de Química, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-909, Brazil
| | - Carolline M A Lorentino
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
| | - Pedro F Barbosa
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
| | - Lívia S Ramos
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
| | - Iuri C Barcellos
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
- Instituto Federal de Educação, Ciência e Tecnologia do Rio de Janeiro (IFRJ), Rio de Janeiro, RJ, 20270-220, Brazil
| | - Lucas Giovanini
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
| | - Lucieri O P Souza
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
| | - Simone S C Oliveira
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
| | - Olufunso O Abosede
- Department of Chemistry, Federal University Otuoke, P.M.B 126, Yenagoa, Bayelsa State, Nigeria
- Department of Chemistry, Nelson Mandela University, PO Box 77000, Port Elizabeth, 6031, South Africa
| | - Adeniyi S Ogunlaja
- Department of Chemistry, Nelson Mandela University, PO Box 77000, Port Elizabeth, 6031, South Africa
| | - Matheus M Pereira
- Chemical Engineering Processes and Forest Products Research Centre (CIEPQPF), Department of Chemical Engineering, University of Coimbra, 3030-790, Coimbra, Portugal
| | - Marta H Branquinha
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil
- Rede Micologia RJ - Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Rio de Janeiro, 21941-901, Brazil
| | - André L S Santos
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-901, Brazil.
- Programa de Pós-Graduação Em Bioquímica (PPGBq), Instituto de Química, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-909, Brazil.
- Rede Micologia RJ - Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Rio de Janeiro, 21941-901, Brazil.
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Andrejević TP, Aleksic I, Kljun J, Počkaj M, Zlatar M, Vojnovic S, Nikodinovic-Runic J, Turel I, Djuran MI, Glišić BĐ. Copper(ii) and silver(i) complexes with dimethyl 6-(pyrazine-2-yl)pyridine-3,4-dicarboxylate (py-2pz): the influence of the metal ion on the antimicrobial potential of the complex. RSC Adv 2023; 13:4376-4393. [PMID: 36744286 PMCID: PMC9890663 DOI: 10.1039/d2ra07401j] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 01/19/2023] [Indexed: 02/04/2023] Open
Abstract
Dimethyl 6-(pyrazine-2-yl)pyridine-3,4-dicarboxylate (py-2pz) was used as a ligand for the synthesis of new copper(ii) and silver(i) complexes, [CuCl2(py-2pz)]2 (1), [Cu(CF3SO3)(H2O)(py-2pz)2]CF3SO3·2H2O (2), [Ag(py-2pz)2]PF6 (3) and {[Ag(NO3)(py-2pz)]·0.5H2O} n (4). The complexes were characterized by spectroscopic and electrochemical methods, while their structures were determined by single crystal X-ray diffraction analysis. The X-ray analysis revealed the bidentate coordination mode of py-2pz to the corresponding metal ion via its pyridine and pyrazine nitrogen atoms in all complexes, while in polynuclear complex 4, the heterocyclic pyrazine ring of one py-2pz additionally behaves as a bridging ligand between two Ag(i) ions. DFT calculations were performed to elucidate the structures of the investigated complexes in solution. The antimicrobial potential of the complexes 1-4 was evaluated against two bacterial (Pseudomonas aeruginosa and Staphylococcus aureus) and two Candida (C. albicans and C. parapsilosis) species. Silver(i) complexes 3 and 4 have shown good antibacterial and antifungal properties with minimal inhibitory concentration (MIC) values ranging from 4.9 to 39.0 μM (3.9-31.2 μg mL-1). All complexes inhibited the filamentation of C. albicans and hyphae formation, while silver(i) complexes 3 and 4 had also the ability to inhibit the biofilm formation process of this fungus. The binding affinity of the complexes 1-4 with calf thymus DNA (ct-DNA) and bovine serum albumin (BSA) was studied by fluorescence emission spectroscopy to clarify the mode of their antimicrobial activity. Catechol oxidase biomimetic catalytic activity of copper(ii) complexes 1 and 2 was additionally investigated by using 3,5-di-tert-butylcatechol (3,5-DTBC) and o-aminophenol (OAP) as substrates.
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Affiliation(s)
- Tina P Andrejević
- Department of Chemistry, Faculty of Science, University of Kragujevac R. Domanovića 12 34000 Kragujevac Serbia
| | - Ivana Aleksic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade Vojvode Stepe 444a 11042 Belgrade Serbia
| | - Jakob Kljun
- Faculty of Chemistry and Chemical Technology, University of Ljubljana Večna Pot 113 Ljubljana SI-1000 Slovenia
| | - Marta Počkaj
- Faculty of Chemistry and Chemical Technology, University of Ljubljana Večna Pot 113 Ljubljana SI-1000 Slovenia
| | - Matija Zlatar
- Department of Chemistry, University of Belgrade-Institute of Chemistry, Technology and Metallurgy Njegoševa 12 11000 Belgrade Serbia
| | - Sandra Vojnovic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade Vojvode Stepe 444a 11042 Belgrade Serbia
| | - Jasmina Nikodinovic-Runic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade Vojvode Stepe 444a 11042 Belgrade Serbia
| | - Iztok Turel
- Faculty of Chemistry and Chemical Technology, University of Ljubljana Večna Pot 113 Ljubljana SI-1000 Slovenia
| | - Miloš I Djuran
- Serbian Academy of Sciences and Arts Knez Mihailova 35 11000 Belgrade Serbia
| | - Biljana Đ Glišić
- Department of Chemistry, Faculty of Science, University of Kragujevac R. Domanovića 12 34000 Kragujevac Serbia
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Zinc(II) Complexes with Dimethyl 2,2′-Bipyridine-4,5-dicarboxylate: Structure, Antimicrobial Activity and DNA/BSA Binding Study. INORGANICS 2022. [DOI: 10.3390/inorganics10060071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Two zinc(II) complexes with dimethyl 2,2′-bipyridine-4,5-dicarboxylate (py-2py) of the general formula [Zn(py-2py)X2], X = Cl− (1) and Br− (2) were synthesized and characterized by NMR, IR and UV-Vis spectroscopy and single-crystal X-ray diffraction analysis. Complexes 1 and 2 are isostructural and adopt a slightly distorted tetrahedral geometry with values of tetrahedral indices τ4 and τ’4 in the range of 0.80–0.85. The complexes were evaluated for their in vitro antimicrobial activity against two bacterial (Pseudomonas aeruginosa and Staphylococcus aureus) and two fungal strains (Candida albicans and Candida parapsilosis), while their cytotoxicity was tested on the normal human lung fibroblast cell line (MRC-5) and the model organism Caenorhabditis elegans. Complex 1 showed moderate activity against both Candida strains. However, this complex was twofold more cytotoxic compared to complex 2. The complexes tested had no effect on the survival rate of C. elegans. Complex 2 showed the ability to inhibit filamentation of C. albicans, while complex 1 was more effective than complex 2 in inhibiting biofilm formation. The interactions of complexes 1 and 2 with calf thymus DNA (ct-DNA) and bovine serum albumin (BSA) were studied to evaluate their binding affinity toward these biomolecules.
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Hong HLT, Huu TN, Anh TD, Nhat KN, Pham Quoc L, Thanh Dang T, Nguyen H, Van Meervelt L. Synthesis, crystal structures and anticancer activities of Cu(II), Zn(II) and Cd(II) complexes containing bis(2-pyridyl)-di(4-methoxyphenyl)ethene. J COORD CHEM 2022. [DOI: 10.1080/00958972.2022.2051498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Hai Le Thi Hong
- Department of Chemistry, Ha Noi National University of Education, Ha Noi, Vietnam
| | - Thinh Nguyen Huu
- Department of Chemistry, Ha Noi National University of Education, Ha Noi, Vietnam
| | - Tho Duong Anh
- Department of Chemistry, Ha Noi National University of Education, Ha Noi, Vietnam
| | - Khanh Nguyen Nhat
- Department of Chemistry, Ha Noi National University of Education, Ha Noi, Vietnam
| | - Long Pham Quoc
- Department of Chemistry, Ha Noi National University of Education, Ha Noi, Vietnam
| | - Tuan Thanh Dang
- Department of Chemistry, Ha Noi University of Science, Ha Noi, Vietnam
| | - Hien Nguyen
- Department of Chemistry, Ha Noi National University of Education, Ha Noi, Vietnam
| | - Luc Van Meervelt
- Biomolecular Architecture, Chemistry Department KU Leuven, Leuven, Belgium
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Bouz G, Doležal M. Advances in Antifungal Drug Development: An Up-To-Date Mini Review. Pharmaceuticals (Basel) 2021; 14:1312. [PMID: 34959712 PMCID: PMC8706862 DOI: 10.3390/ph14121312] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/11/2021] [Accepted: 12/14/2021] [Indexed: 12/20/2022] Open
Abstract
The utility of clinically available antifungals is limited by their narrow spectrum of activity, high toxicity, and emerging resistance. Antifungal drug discovery has always been a challenging area, since fungi and their human host are eukaryotes, making it difficult to identify unique targets for antifungals. Novel antifungals in clinical development include first-in-class agents, new structures for an established target, and formulation modifications to marketed antifungals, in addition to repurposed agents. Membrane interacting peptides and aromatherapy are gaining increased attention in the field. Immunotherapy is another promising treatment option, with antifungal antibodies advancing into clinical trials. Novel targets for antifungal therapy are also being discovered, allowing the design of new promising agents that may overcome the resistance issue. In this mini review, we will summarize the current status of antifungal drug pipelines in clinical stages, and the most recent advancements in preclinical antifungal drug development, with special focus on their chemistry.
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Affiliation(s)
- Ghada Bouz
- Faculty of Pharmacy in Hradec Králové, Charles University, 50005 Hradec Králové, Czech Republic
| | - Martin Doležal
- Faculty of Pharmacy in Hradec Králové, Charles University, 50005 Hradec Králové, Czech Republic
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Lin Y, Betts H, Keller S, Cariou K, Gasser G. Recent developments of metal-based compounds against fungal pathogens. Chem Soc Rev 2021; 50:10346-10402. [PMID: 34313264 DOI: 10.1039/d0cs00945h] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This review provides insight into the rapidly expanding field of metal-based antifungal agents. In recent decades, the antibacterial resistance crisis has caused reflection on many aspects of public health where weaknesses in our medicinal arsenal may potentially be present - including in the treatment of fungal infections, particularly in the immunocompromised and those with underlying health conditions where mortality rates can exceed 50%. Combination of organic moieties with known antifungal properties and metal ions can lead to increased bioavailability, uptake and efficacy. Development of such organometallic drugs may alleviate pressure on existing antifungal medications. Prodigious antimicrobial moieties such as azoles, Schiff bases, thiosemicarbazones and others reported herein lend themselves easily to the coordination of a host of metal ions, which can vastly improve the biocidal activity of the parent ligand, thereby extending the library of antifungal drugs available to medical professionals for treatment of an increasing incidence of fungal infections. Overall, this review shows the impressive but somewhat unexploited potential of metal-based compounds to treat fungal infections.
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Affiliation(s)
- Yan Lin
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 75005 Paris, France.
| | - Harley Betts
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 75005 Paris, France.
| | - Sarah Keller
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 75005 Paris, France.
| | - Kevin Cariou
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 75005 Paris, France.
| | - Gilles Gasser
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 75005 Paris, France.
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Madajska K, Szymańska IB. New Volatile Perfluorinated Amidine-Carboxylate Copper(II) Complexes as Promising Precursors in CVD and FEBID Methods. MATERIALS (BASEL, SWITZERLAND) 2021; 14:3145. [PMID: 34201158 PMCID: PMC8230148 DOI: 10.3390/ma14123145] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 12/05/2022]
Abstract
In the present study, we have synthesised and characterised newly copper(II) complexes with the general formula [Cu2(NH2(NH=)CC2F5)2(µ-O2CRF)4], where RF = CF3, C2F5, C3F7, C4F9. Infrared spectroscopy, mass spectrometry with electron ionisation (EI MS), and density-functional theory (DFT) calculations were used to confirm compounds' composition and structure. The volatility of the compounds was studied using thermal analysis (TGA), EI MS mass spectrometry, variable temperature infrared spectroscopy (VT IR), and sublimation experiments. Research has revealed that these compounds are the source of metal carriers in the gas phase. The thermal decomposition mechanism over reduced pressure was proposed. TGA studies demonstrated that copper transfer to the gaseous phase occurs even at atmospheric pressure. Two selected complexes [Cu2(NH2(NH=)CC2F5)2(µ-O2CC2F5)4] and [Cu2(NH2(NH=)CC2F5)2(µ-O2CC3F7)4] were successful used as chemical vapour deposition precursors. Copper films were deposited with an evaporation temperature of 393 K and 453 K, respectively, and a decomposition temperature in the range of 573-633 K without the use of hydrogen. The microscopic observations made to investigate the interaction of the [Cu2(NH2(NH=)CC2F5)2(µ-O2CC2F5)4] with the electron beam showed that the ligands are completely lost under transmission electron microscopy analysis conditions (200 keV), and the final product is copper(II) fluoride. In contrast, the beam energy in scanning electron microscopy (20 keV) was insufficient to break all coordination bonds. It was shown that the Cu-O bond is more sensitive to the electron beam than the Cu-N bond.
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Affiliation(s)
| | - Iwona Barbara Szymańska
- Department of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland;
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