1
|
Anokhin D, Maryasevskaya A, Abukaev A, Ozkose UU, Buglakov A, Ivanov DA, Améduri B. Synthesis of Calamitic Fluorinated Mesogens with Complex Crystallization Behavior. Molecules 2023; 28:8002. [PMID: 38138492 PMCID: PMC10745429 DOI: 10.3390/molecules28248002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
This work presents the synthesis and self-organization of the calamitic fluorinated mesogen, 1,1,2,2-tetrafluoro-2-(1,1,2,2-tetrafluoro-4-iodobutoxy)ethanesulfonic acid, a potential model for perfluorosulfonic acid membranes (PFSA). The compound is derived in three steps from 1,1,2,2-tetrafluoro-2-(1,1,2,2-tetrafluoro-2-iodoethoxy)ethanesulfonyl fluoride, achieving a 78% overall yield. The resulting compound exhibits intricate thermal behavior. At 150 °C, a crystal-to-crystal transition is observed due to the partial disordering of calamitic molecules, which is followed by isotropization at 218 °C. Upon cooling, sample ordering occurs through the formation of large smectic liquid crystalline phase domains. This thermotropic state transforms into a layered crystal phase at lower temperatures, characterized by alternating hydrophilic and hydrophobic layers. Using X-ray diffraction, crystalline unit cell models at both room temperature and 170 °C were proposed. Computer simulations of the molecule across varying temperatures support the idea that thermal transitions correlate with a loss of molecular orientation. Importantly, the study underscores the pivotal role of precursor self-organization in aligning channels during membrane fabrication, ensuring controlled and oriented positioning.
Collapse
Affiliation(s)
- Denis Anokhin
- Faculty of Chemistry, Lomonosov Moscow State University, GSP-1, 1-3 Leninskiye Gory, 119991 Moscow, Russia (A.A.); (A.B.); (D.A.I.)
- Scientific Center for Genetics and Life Sciences, Sirius University of Science and Technology, 1 Olympic Ave., 354340 Sochi, Russia
| | - Alina Maryasevskaya
- Faculty of Chemistry, Lomonosov Moscow State University, GSP-1, 1-3 Leninskiye Gory, 119991 Moscow, Russia (A.A.); (A.B.); (D.A.I.)
| | - Ainur Abukaev
- Faculty of Chemistry, Lomonosov Moscow State University, GSP-1, 1-3 Leninskiye Gory, 119991 Moscow, Russia (A.A.); (A.B.); (D.A.I.)
| | - Umut Ugur Ozkose
- Institut Charles Gerhardt, CNRS, University of Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, 34000 Montpellier, France;
- Department of Chemistry, Faculty of Science and Letters, Piri Reis University, Tuzla, Istanbul 34940, Turkey
| | - Alexander Buglakov
- Faculty of Chemistry, Lomonosov Moscow State University, GSP-1, 1-3 Leninskiye Gory, 119991 Moscow, Russia (A.A.); (A.B.); (D.A.I.)
- A. N. Nesmeyanov Institute of Organoelement Compounds RAS, Vavilova ul., 28, 119334 Moscow, Russia
| | - Dimitri A. Ivanov
- Faculty of Chemistry, Lomonosov Moscow State University, GSP-1, 1-3 Leninskiye Gory, 119991 Moscow, Russia (A.A.); (A.B.); (D.A.I.)
- Scientific Center for Genetics and Life Sciences, Sirius University of Science and Technology, 1 Olympic Ave., 354340 Sochi, Russia
- Institut de Sciences des Matériaux de Mulhouse-IS2M, CNRS UMR 7361, Jean Starcky 15, 68057 Mulhouse, France
| | - Bruno Améduri
- Faculty of Chemistry, Lomonosov Moscow State University, GSP-1, 1-3 Leninskiye Gory, 119991 Moscow, Russia (A.A.); (A.B.); (D.A.I.)
- Institut Charles Gerhardt, CNRS, University of Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, 34000 Montpellier, France;
| |
Collapse
|
2
|
Johannessen K, Johansen MAL, Einrem RF, McCormick McPherson LJ, Alemayehu AB, Borisov SM, Ghosh A. Influence of Fluorinated Substituents on the Near-Infrared Phosphorescence of 5d Metallocorroles. ACS Org Inorg Au 2023; 3:241-245. [PMID: 37810408 PMCID: PMC10557119 DOI: 10.1021/acsorginorgau.3c00016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 10/10/2023]
Abstract
The influence of fluorinated substituents on the luminescent properties of rhenium-oxo, osmium-nitrido, and gold triarylcorroles was studied via a comparison of four ligands: triphenylcorrole (TPC), tris(p-trifluoromethylphenyl)corrole (TpCF3PC), tris{3,5-bis(trifluoromethyl)phenyl}corrole (T3,5-CF3PC), and tris(pentafluorophenyl)corrole (TPFPC). For each metal series examined, fluorinated substituents were found to enhance the luminescent properties, with the phosphorescence quantum yields and triplet decay times increasing in the order TPC < TpCF3PC < T3,5-CF3PC < TPFPC. Among the 11 complexes examined, the highest phosphorescence quantum yield, 2.2%, was recorded for Re[TPFPC](O).
Collapse
Affiliation(s)
| | | | - Rune F. Einrem
- Department
of Chemistry, UiT−The Arctic University
of Norway, 9037 Tromsø, Norway
| | - Laura J. McCormick McPherson
- EPSRC
National Crystallography Service, School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, U.K.
| | - Abraham B. Alemayehu
- Department
of Chemistry, UiT−The Arctic University
of Norway, 9037 Tromsø, Norway
| | - Sergey M. Borisov
- Institute
of Analytical Chemistry and Food Chemistry, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Abhik Ghosh
- Department
of Chemistry, UiT−The Arctic University
of Norway, 9037 Tromsø, Norway
| |
Collapse
|
3
|
Oboňová B, Habala L, Litecká M, Herich P, Bilková A, Bilka F, Horváth B. Antimicrobially Active Zn(II) Complexes of Reduced Schiff Bases Derived from Cyclohexane-1,2-diamine and Fluorinated Benzaldehydes-Synthesis, Crystal Structure and Bioactivity. Life (Basel) 2023; 13:1516. [PMID: 37511891 PMCID: PMC10381420 DOI: 10.3390/life13071516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/30/2023] [Accepted: 07/03/2023] [Indexed: 07/30/2023] Open
Abstract
A series of Schiff base ligands obtained by the condensation of trans-cyclohexane-1,2-diamine and fluorinated benzaldehydes were prepared, followed by their reduction with NaBH4. The reduced ligands were employed in the synthesis of zinc complexes of the general formula [ZnCl2(L)]. The structures of both the original and the reduced Schiff bases, as well as of the zinc complexes, were characterized by single-crystal X-ray analysis, along with NMR and IR spectroscopy. The antimicrobial activities of the reduced Schiff bases and their zinc complexes were evaluated in vitro against E. coli, S. aureus, and C. albicans. The compounds containing the 4-(trifluoromethylphenyl) moiety showed marked antibacterial activity. Interestingly, the antimicrobial effect of the zinc complex with this moiety was significantly higher than that of the corresponding free reduced ligand, comparable with ciprofloxacin used as standard. Thus, a synergic effect upon the complexation with zinc can be inferred.
Collapse
Affiliation(s)
- Bianka Oboňová
- Department of Chemical Theory of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, 832 32 Bratislava, Slovakia
| | - Ladislav Habala
- Department of Chemical Theory of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, 832 32 Bratislava, Slovakia
| | - Miroslava Litecká
- Department of Materials Chemistry, Institute of Inorganic Chemistry of the CAS, Husinec-Řež č.p. 1001, 250 68 Řež, Czech Republic
| | - Peter Herich
- Department of Chemical Theory of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, 832 32 Bratislava, Slovakia
- Department of Physical Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava, Slovakia
| | - Andrea Bilková
- Department of Cellular and Molecular Biology of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, 832 32 Bratislava, Slovakia
| | - František Bilka
- Department of Cellular and Molecular Biology of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, 832 32 Bratislava, Slovakia
| | - Branislav Horváth
- NMR Laboratory, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, 832 32 Bratislava, Slovakia
| |
Collapse
|
4
|
Utecht-Jarzyńska G, Nagła K, Mlostoń G, Heimgartner H, Palusiak M, Jasiński M. A straightforward conversion of 1,4-quinones into polycyclic pyrazoles via [3 + 2]-cycloaddition with fluorinated nitrile imines. Beilstein J Org Chem 2021; 17:1509-1517. [PMID: 34285722 PMCID: PMC8261526 DOI: 10.3762/bjoc.17.108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 06/17/2021] [Indexed: 11/23/2022] Open
Abstract
In-situ-generated N-aryl nitrile imines derived from trifluoroacetonitrile efficiently react with polycyclic 1,4-quinones, yielding fused pyrazole derivatives as the exclusive products. The reactions proceed via the initially formed [3 + 2]-cycloadducts, which undergo spontaneous aerial oxidation to give aromatized heterocyclic products. Only for 2,3,5,6-tetramethyl-1,4-benzoquinone, the expected [3 + 2]-cycloadduct exhibited fair stability and could be isolated in moderate yield (53%). The presented method offers a straightforward access to hitherto little known trifluoromethylated polycyclic pyrazoles. All products were isolated as pale colored solids with medium-intensity absorption maxima in the range of 310-340 nm for naphthoquinone-derived products and low-intensity bands in the visible region (≈400 nm) for the anthraquinone series.
Collapse
Affiliation(s)
- Greta Utecht-Jarzyńska
- Department of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91403 Łódź, Poland
| | - Karolina Nagła
- Department of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91403 Łódź, Poland
| | - Grzegorz Mlostoń
- Department of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91403 Łódź, Poland
| | - Heinz Heimgartner
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Marcin Palusiak
- Department of Physical Chemistry, Faculty of Chemistry, University of Lodz, Pomorska 163/165, 90236 Łódź, Poland
| | - Marcin Jasiński
- Department of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91403 Łódź, Poland
| |
Collapse
|
5
|
Uno H, Fujimoto D, Harada K, Tanaka C, Shibata N. Synthesis of Tetra-Substituted Trifluoromethyl-3,1-Benzoxazines by Transition-Metal-Catalyzed Decarboxylative Cyclization of N-Benzoyl Benzoxazinones. ChemistryOpen 2021; 10:518-522. [PMID: 33605087 PMCID: PMC8095294 DOI: 10.1002/open.202000360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/02/2021] [Indexed: 12/16/2022] Open
Abstract
Efficient synthesis of N,O-heterocyclic tetra-substituted trifluoromethyl-3,1-benzoxazines via a transition-metal-catalyzed decarboxylative intramolecular cyclization was achieved. The decarboxylation of N-benzoyl trifluoromethyl-benzoxazinones generated the amide oxygen nucleophile, allowing a selective internal C1 -attack on Pd- or Cu-coordinated zwitterions, affording medicinally attractive tetra-substituted vinyl- or ethynyl-trifluoromethyl-3,1-benzoxazines. This protocol can be applied to the synthesis of perfluoroalkyl- and non-fluorinated 3,1-benzoxazines.
Collapse
Affiliation(s)
- Hiroto Uno
- Department of Nanopharmaceutical SciencesNagoya Institute of Technology Gokiso, Showa-kuNagoya466-8555Japan
| | - Daichi Fujimoto
- Department of Life Science and Applied ChemistryNagoya Institute of Technology Gokiso, Showa-kuNagoya466-8555Japan
| | - Kyosuke Harada
- Department of Life Science and Applied ChemistryNagoya Institute of Technology Gokiso, Showa-kuNagoya466-8555Japan
| | - Chika Tanaka
- Department of Life Science and Applied ChemistryNagoya Institute of Technology Gokiso, Showa-kuNagoya466-8555Japan
| | - Norio Shibata
- Department of Nanopharmaceutical SciencesNagoya Institute of Technology Gokiso, Showa-kuNagoya466-8555Japan
- Department of Life Science and Applied ChemistryNagoya Institute of Technology Gokiso, Showa-kuNagoya466-8555Japan
- Institute of Advanced Fluorine-Containing MaterialsZhejiang Normal University688 Yingbin Avenue321004JinhuaP. R. China
| |
Collapse
|
6
|
Stoian C, Olaru M, Cucuiet TA, Kegyes KT, Sava A, Timoshkin AY, Raţ CI, Beckmann J. Bulky Polyfluorinated Terphenyldiphenylboranes: Water Tolerant Lewis Acids. Chemistry 2021; 27:4327-4331. [PMID: 33368648 PMCID: PMC7986919 DOI: 10.1002/chem.202005367] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Indexed: 11/23/2022]
Abstract
Protocols for the synthesis of the bulky polyfluorinated triarylboranes 2,6‐(C6F5)2C6F3B(C6F5)2 (1), 2,6‐(C6F5)2C6F3B[3,5‐(CF3)2C6H3] (2), 2,4,6‐(C6F5)3C6H2B(C6F5)2 (3), 2,4,6‐(C6F5)3C6H2B[3,5‐(CF3)2C6H3] (4) were developed. All boranes are water tolerant and according to the Gutmann‐Beckett method, 1–3 display Lewis acidities larger than that of the prominent B(C6F5)3.
Collapse
Affiliation(s)
- Corina Stoian
- Institut für Anorganische Chemie und Kristallographie, Universität Bremen, Leobener Straße 7, 28359, Bremen, Germany.,Department of Chemistry, Supramolecular Organic and Organometallic Chemistry Centre (SOOMCC), Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Arany János Steet 11, 400028, Cluj-Napoca, Romania
| | - Marian Olaru
- Institut für Anorganische Chemie und Kristallographie, Universität Bremen, Leobener Straße 7, 28359, Bremen, Germany
| | - Teodor A Cucuiet
- Department of Chemistry, Supramolecular Organic and Organometallic Chemistry Centre (SOOMCC), Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Arany János Steet 11, 400028, Cluj-Napoca, Romania
| | - Krisztina T Kegyes
- Department of Chemistry, Supramolecular Organic and Organometallic Chemistry Centre (SOOMCC), Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Arany János Steet 11, 400028, Cluj-Napoca, Romania
| | - Alexandru Sava
- Department of Chemistry, Supramolecular Organic and Organometallic Chemistry Centre (SOOMCC), Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Arany János Steet 11, 400028, Cluj-Napoca, Romania
| | - Alexey Y Timoshkin
- Institute of Chemistry, St. Petersburg State University, Universitetskaya emb. 7/9, 199034, St. Petersburg, Russia
| | - Ciprian I Raţ
- Department of Chemistry, Supramolecular Organic and Organometallic Chemistry Centre (SOOMCC), Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Arany János Steet 11, 400028, Cluj-Napoca, Romania
| | - Jens Beckmann
- Institut für Anorganische Chemie und Kristallographie, Universität Bremen, Leobener Straße 7, 28359, Bremen, Germany
| |
Collapse
|
7
|
Kawanishi R, Nakada K, Shibatomi K. Decarboxylative trifluoromethylthiolation of pyridylacetates. Beilstein J Org Chem 2021; 17:229-233. [PMID: 33564333 PMCID: PMC7849234 DOI: 10.3762/bjoc.17.23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 01/04/2021] [Indexed: 01/27/2023] Open
Abstract
Decarboxylative trifluoromethylthiolation of lithium pyridylacetates was achieved using N-(trifluoromethylthio)benzenesulfonimide as the electrophilic trifluoromethylthiolation reagent. The reaction afforded the corresponding trifluoromethyl thioethers in good yield. Furthermore, the preparation of lithium pyridylacetates by saponification of the corresponding methyl esters and subsequent decarboxylative trifluoromethylthiolation were performed in a one-pot fashion.
Collapse
Affiliation(s)
- Ryouta Kawanishi
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441-8580, Japan
| | - Kosuke Nakada
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441-8580, Japan
| | - Kazutaka Shibatomi
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441-8580, Japan
| |
Collapse
|
8
|
Ouedraogo NAN, Yan H, Han CB, Zhang Y. Influence of Fluorinated Components on Perovskite Solar Cells Performance and Stability. Small 2021; 17:e2004081. [PMID: 33522104 DOI: 10.1002/smll.202004081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 10/12/2020] [Indexed: 06/12/2023]
Abstract
Several valuable scientific investigations have been conducted these last few years in materials design and device engineering for perovskite solar cells (PSCs) to make them competitive compared to traditional silicon-based photovoltaic technologies. Consequently, high power conversion efficiency beyond 25% is nowadays reported. However, their long-term stability remains a significant challenge to overcome. Herein, the influence of fluorinated compounds on each layer of PSCs devices and their impact on the resulted device performances and stability is spotlighted. The fluorinated compounds exhibit attractive properties due to their very high electronegativity attributed to the fluorine atom, and their strong hydrophobicity. Thus, the introduction of these compounds is found to be a successful strategy to positively suppress the surface trap states, enhancing charge collection and reducing interfacial charge recombination. Besides, a better film quality and better energy level alignment is obtained, resulting in the improvement of device photovoltaic parameters such as the open-circuit voltage (Voc ), short-circuit current (Jsc ), and fill factor (FF), and then, the device's overall power conversion efficiency (PCE). Their long-term stability is also found to further be improved.
Collapse
Affiliation(s)
- Nabonswende Aida Nadege Ouedraogo
- College of Materials Science and Engineering, Beijing University of Technology, Beijing, 100124, China
- The Key Laboratory of Advanced Functional Materials, Ministry of Education of China, Beijing, 100124, China
| | - Hui Yan
- College of Materials Science and Engineering, Beijing University of Technology, Beijing, 100124, China
- The Key Laboratory of Advanced Functional Materials, Ministry of Education of China, Beijing, 100124, China
| | - Chang Bao Han
- College of Materials Science and Engineering, Beijing University of Technology, Beijing, 100124, China
- The Key Laboratory of Advanced Functional Materials, Ministry of Education of China, Beijing, 100124, China
| | - Yongzhe Zhang
- College of Materials Science and Engineering, Beijing University of Technology, Beijing, 100124, China
- The Key Laboratory of Advanced Functional Materials, Ministry of Education of China, Beijing, 100124, China
| |
Collapse
|
9
|
Lagu SB, Yejella RP, Bhandare RR, Shaik AB. Design, Synthesis, and Antibacterial and Antifungal Activities of Novel Trifluoromethyl and Trifluoromethoxy Substituted Chalcone Derivatives. Pharmaceuticals (Basel) 2020; 13:E375. [PMID: 33182305 PMCID: PMC7695348 DOI: 10.3390/ph13110375] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/05/2020] [Accepted: 11/05/2020] [Indexed: 01/12/2023] Open
Abstract
Despite the availability of many drugs to treat infectious diseases, the problems like narrow antimicrobial spectrum, drug resistance, hypersensitivities and systemic toxicities are hampering their clinical utility. Based on the above facts, in the present study, we designed, synthesized and evaluated the antibacterial and antifungal activity of novel fluorinated compounds comprising of chalcones bearing trifluoromethyl (A1-A10) and trifluoromethoxy (B1-B10) substituents. The compounds were characterized by spectroscopic techniques and evaluated for their antimicrobial activity against four pathogenic Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli and Bacillus subtilis) bacterial and fungal (Candida albicans and Aspergillus niger) strains. In this study, the compounds with trifluoromethoxy group were more effective than those with trifluoromethyl group. Among the 20 fluorinated chalcones, compound A3/B3 bearing an indole ring attached to the olefinic carbon have been proved to possess the most antimicrobial activity compared to the standard drugs without showing cytotoxicity on human normal liver cell line (L02). Further, the minimum inhibitory concentration (MIC) for A3/B3 was determined by serial tube dilution method and showed potential activity. These results would provide promising access to future study about the development of novel agents against bacterial and fungal infections.
Collapse
Affiliation(s)
- Surendra Babu Lagu
- Department of Pharmaceutical Sciences, Pharmaceutical Chemistry Division, A.U. College of Pharmaceutical Sciences, Andhra University, Visakhapatnam 530003, Andhra Pradesh, India;
| | - Rajendra Prasad Yejella
- Department of Pharmaceutical Sciences, Pharmaceutical Chemistry Division, A.U. College of Pharmaceutical Sciences, Andhra University, Visakhapatnam 530003, Andhra Pradesh, India;
| | - Richie R. Bhandare
- Department of Pharmaceutical Sciences, College of Pharmacy & Health Sciences, Ajman University, Ajman P.O. Box 346, UAE
| | - Afzal B. Shaik
- Department of Pharmaceutical Chemistry, Vignan Pharmacy College, Vadlamudi 522213, Andhra Pradesh, India
| |
Collapse
|
10
|
Silva DR, Daré JK, Freitas MP. Conformational preferences of fluorine-containing agrochemicals and their implications for lipophilicity prediction. Beilstein J Org Chem 2020; 16:2469-2476. [PMID: 33093926 PMCID: PMC7554678 DOI: 10.3762/bjoc.16.200] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 09/23/2020] [Indexed: 12/14/2022] Open
Abstract
Molecular polarity governs lipophilicity, which in turn determines important agrochemical and environmental properties, such as soil sorption and bioconcentration of organic compounds. Since the C-F bond is the most polar in organic chemistry, the orientation of fluorine substituents originating from the rotation around C-C(F) bonds should affect the polarity and, consequently, the physicochemical and biological properties of fluorine-containing agrochemicals. Accordingly, this study aims to determine the most likely conformers of some fluorine-containing agrochemicals and to correlate their molecular dipole moments with the respective n-octanol/water partition coefficients (log P), in order to investigate the dependence of the lipophilicity with the molecular conformation.
Collapse
Affiliation(s)
| | - Joyce K Daré
- Department of Chemistry, Federal University of Lavras, 37200-900, Lavras-MG, Brazil
| | - Matheus P Freitas
- Department of Chemistry, Federal University of Lavras, 37200-900, Lavras-MG, Brazil
| |
Collapse
|
11
|
Caivano I, Tošner Z, Císařová I, Nečas D, Kotora M. A General Synthetic Approach and Photophysical Properties of Regioselectively Fluorinated [5]- and [6]-Helical Bispiroindenofluorenes. Chempluschem 2020; 85:2010-2016. [PMID: 32881370 DOI: 10.1002/cplu.202000434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/05/2020] [Indexed: 11/11/2022]
Abstract
A first series of fluorinated [n]helical compounds (n=5 and 6) with the dihydroindenofluorene scaffold was prepared in 5 or 9 (octafluorinated dihydroindenofluorene) steps and their photophysical properties were determined. Rh-catalyzed intramolecular [2+2+2] cyclotrimerization of triyndiols, which were prepared in a modular fashion from simple starting material such as fluorinated haloarylcarbaldehydes, to the intermediate [n]helical dihydroindeno[2,1-c]fluorene-5,8-diols was the crucial synthetic step and proceeded with high efficacy. Their further transformation gave the desired selectively fluorinated bispirodihydroindeno[2,1-c]fluorenes. Their absorption and emission spectra were recorded. The fluorescence quantum yields were up to 92 % and the emission maxima were red-shifted in comparison with their non-fluorinated counterparts (386-413 nm).
Collapse
Affiliation(s)
- Ilaria Caivano
- Department of Organic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43, Praha 2, Czech Republic
| | - Zdeněk Tošner
- NMR Laboratory, Faculty of Science, Charles University, Hlavova 8, 128 43, Praha 2, Czech Republic
| | - Ivana Císařová
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43, Praha 2, Czech Republic
| | - David Nečas
- Department of Organic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43, Praha 2, Czech Republic
| | - Martin Kotora
- Department of Organic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43, Praha 2, Czech Republic
| |
Collapse
|
12
|
Abstract
1H/19F NMR-based screening methods were applied to a human serum albumin-fleroxacin complex. Fleroxacin contains three fluorine atoms in a molecule, which is suitable as a model fluorinated compound for NMR analysis with 1H and 19F detection. The 19F{1H} and 1H{1H} saturation transfer difference spectra were acquired and the 1H/19F spin-lattice relaxation rates were measured with and without any selective irradiation of protein resonance to identify the binding epitopes of fleroxacin. Because several 1H signals of fleroxacin resonated close to water, its precise signal intensities were unavailable. The 19F NMR-based screening methods successfully provide complementary information, indicating its importance in the analysis of fluorinated compounds.
Collapse
Affiliation(s)
- Kazuo Furihata
- Division of Agriculture and Agricultural Life Sciences, The University of Tokyo
| | - Mitsuru Tashiro
- Department of Chemistry, College of Science and Technology, Meisei University
| |
Collapse
|
13
|
Yamada S, Higashida T, Wang Y, Morita M, Hosokai T, Maduwantha K, Koswattage KR, Konno T. Development of fluorinated benzils and bisbenzils as room-temperature phosphorescent molecules. Beilstein J Org Chem 2020; 16:1154-1162. [PMID: 32550930 PMCID: PMC7277987 DOI: 10.3762/bjoc.16.102] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/20/2020] [Indexed: 12/24/2022] Open
Abstract
Pure organic phosphorescent molecules are attractive alternatives to transition-metal-complex-based phosphores for biomedical and technological applications owing to their abundance and nontoxicity. This article discloses the design, synthesis, and photophysical properties of fluorinated benzil and bisbenzil derivatives as potential pure organic room-temperature phosphorescent molecules. These compounds were separately converted from the corresponding fluorinated bistolanes via PdCl2-catalyzed oxidation by dimethyl sulfoxide, while nonfluorinated bistolane provided the corresponding bisbenzil derivatives exclusively in a similar manner. Intensive investigations of the photophysical properties of the benzil and bisbenzil derivatives in toluene at 25 °C showed both fluorescence with a photoluminescence (PL) band at a maximum wavelength (λPL) of around 400 nm and phosphorescence with a PL band at a λPL of around 560 nm. Interestingly, intersystem crossing effectively caused fluorinated benzils to emit phosphorescence, which may arise from immediate spin-orbit coupling involving the 1(n, π)→3(π, π) transition, unlike the case of fluorinated or nonfluorinated bisbenzil analogues. These findings offer a useful guide for developing novel pure organic room-temperature phosphorescent materials.
Collapse
Affiliation(s)
- Shigeyuki Yamada
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Takuya Higashida
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Yizhou Wang
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Masato Morita
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Takuya Hosokai
- National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba 305-8560, Japan
| | - Kaveendra Maduwantha
- National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba 305-8560, Japan.,Faculty of Technology, Sabaragamuwa University of Sri Lanka, P.O. Box 02, Belihuloya 70140, Sri Lanka
| | - Kaveenga Rasika Koswattage
- National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba 305-8560, Japan.,Faculty of Technology, Sabaragamuwa University of Sri Lanka, P.O. Box 02, Belihuloya 70140, Sri Lanka
| | - Tsutomu Konno
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| |
Collapse
|
14
|
Tsunemi T, Bernardino SJ, Mendoza A, Jones CG, Harran PG. Syntheses of Atypically Fluorinated Peptidyl Macrocycles through Sequential Vinylic Substitutions. Angew Chem Int Ed Engl 2020; 59:674-678. [PMID: 31693283 DOI: 10.1002/anie.201910136] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/09/2019] [Indexed: 12/12/2022]
Abstract
Small peptides containing combinations of cysteine, tyrosine, histidine, and serine residues react with octafluorocyclopentene (OFCP) to afford atypically structured macrocycles through successive vinylic substitutions. The reactions proceed rapidly in air at 0 °C and are tolerant of spectating tryptophan, asparagine, glutamine, and threonine residues. Hexapeptides of consensus sequence YXCXXC displace four fluorine atoms from OFCP to generate fluorinated macrobicyclic compounds that display dual-turn surfaces. The method provides facile access to a wide range of previously unknown heterocyclic structures.
Collapse
Affiliation(s)
- Tomoyuki Tsunemi
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA.,Medicinal Chemistry Research Laboratories, Daiichi Sankyo Co., Ltd., Tokyo, Japan
| | - Salvador J Bernardino
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Angel Mendoza
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Christopher G Jones
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Patrick G Harran
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| |
Collapse
|
15
|
Abstract
Understandings of environmental governance both assume and challenge the relationship between expert knowledge and corresponding action. We explore this interplay by examining the context of knowledge production pertaining to a contested class of chemicals. Per-and polyfluorinated alkyl substances (PFASs) are widely used industrial compounds containing chemical chains of carbon and fluorine that are persistent, bioaccumulative and toxic. Although industry and regulatory scientists have studied the exposure and toxicity concerns of these compounds for decades, and several contaminated communities have documented health concerns as a result of their high levels of exposure, PFAS use remains ubiquitous in a large range of consumer and industrial products. Despite this significant history of industry knowledge production documenting exposure and toxicity concerns, the regulatory approach to PFASs has been limited. This is largely due to a regulatory framework that privileges industry incentives for rapid market entry and trade secret protection over substantive public health protection, creating areas of unseen science, research that is conducted but never shared outside of institutional boundaries. In particular, the risks of PFASs have been both structurally hidden and unexamined by existing regulatory and industry practice. This reveals the uneven pathways that construct issues of social and scientific concern.
Collapse
Affiliation(s)
- Lauren Richter
- Social Science Environmental Health Research Institute, Northeastern University, Boston, MA, USA
- Silent Spring Institute, Newton, MA, USA
| | - Alissa Cordner
- Department of Sociology, Whitman College, Walla Walla, WA, USA
| | - Phil Brown
- Departments of Sociology and Anthropology and Health Sciences, Northeastern University, Boston, MA, USA
| |
Collapse
|
16
|
Abstract
The long-range scalar coupling constant between proton and fluorine nuclei, 5 JHF , is observed to be larger than 3 JHF in the pyrimidinyl moiety of voriconazole. A set of smaller molecules is chosen (fluorobenzene, N-methyl-2-fluoropyridine, N-methyl-3-fluoropyridine, 3-fluoropyridine, 5-pyrimidine, and 2-fluoropyridine) to evaluate the influence of the nitrogen atom in the experimental JHF values. Spectral aliased pure shift heteronuclear single quantum coherence spectroscopy (SAPS-HSQC) is applied to determine the relative sign between the JCF and JHF scalar couplings. Theoretical calculations show that the 3 JHF and 5 JHF coupling constants can be described mainly by a Fermi contact (FC) transmission mechanism. A decomposition analysis of JHF in terms of localized molecular orbital (LMO) contributions allows us to determine that the interaction involving the nitrogen lone pair (LPN) is the main reason for the larger 5 JHF compared to 3 JHF . Our analysis indicates that delocalization of LPN has a positive contribution to the long-range coupling, while a negative one is observed for 3 JHF .
Collapse
Affiliation(s)
- Thaís M Barbosa
- Institute of Chemistry, University of Campinas - UNICAMP, P. O. Box: 6154, 13083-970 -, Campinas - SP -, Brazil
| | - Renan V Viesser
- Institute of Chemistry, University of Campinas - UNICAMP, P. O. Box: 6154, 13083-970 -, Campinas - SP -, Brazil
| | - Lucas G Martins
- Institute of Chemistry, University of Campinas - UNICAMP, P. O. Box: 6154, 13083-970 -, Campinas - SP -, Brazil
| | - Roberto Rittner
- Institute of Chemistry, University of Campinas - UNICAMP, P. O. Box: 6154, 13083-970 -, Campinas - SP -, Brazil
| | - Cláudio F Tormena
- Institute of Chemistry, University of Campinas - UNICAMP, P. O. Box: 6154, 13083-970 -, Campinas - SP -, Brazil
| |
Collapse
|
17
|
Guzei IA, Spencer LC, Buechel SC, Kaufmann LB, Czerwinski CJ. Intricacies of ligand coordination in tricarbonylchromium(0) complexes with ortho- and para-fluorobiphenyls. Acta Crystallogr C Struct Chem 2017; 73:638-644. [PMID: 28776516 DOI: 10.1107/s2053229617010774] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 07/21/2017] [Indexed: 11/10/2022] Open
Abstract
The steric and electronic factors that influence which of the two rings of a substituted biphenyl ligand coordinates to chromium are of interest and it has been suggested that haptotropic rearrangements within these molecules may be limited if the arene-arene dihedral angle is too large. Two tricarbonylchromium(0) complexes and their respective free ligands have been characterized by single-crystal X-ray diffraction. In the solid state, tricarbonyl[(1',2',3',4',5',6'-η)-2-fluoro-1,1'-biphenyl]chromium(0), [Cr(C12H9F)(CO)3], (I), exists as the more stable isomer with the nonhalogenated arene ring ligated to the metal center. Similarly, tricarbonyl[(1',2',3',4',5',6'-η)-4-fluoro-1,1'-biphenyl]chromium(0) crystallizes as the more stable isomer with the phenyl ring bonded to the Cr0 center. The arene-arene dihedral angles in these complexes are 55.77 (4) and 52.4 (5)°, respectively. Structural features of these complexes are compared to those of the DFT-optimized geometries of ten tricarbonyl[(η6-C6H5)(4-F-C6H4)]chromium model complexes. The solid-state structures of the free ligands 2-fluoro-1,1'-biphenyl and 4-fluoro-1,1'-biphenyl, both C12H9F, exhibit arene-arene dihedral angles of 54.83 (7) and 0.71 (8)°, respectively. The molecules of the free ligands occupy crystallographic twofold axes and exhibit positional disorder. Weak intermolecular C-H...F interactions are observed in all four structures.
Collapse
Affiliation(s)
- Ilia A Guzei
- Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706, USA
| | - Lara C Spencer
- Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706, USA
| | - Sondra C Buechel
- Department of Chemistry and Biochemistry, University of Wisconsin-La Crosse, 1725 State Street, La Crosse, WI 54601, USA
| | - Leah B Kaufmann
- Department of Chemistry and Biochemistry, University of Wisconsin-La Crosse, 1725 State Street, La Crosse, WI 54601, USA
| | - Curtis J Czerwinski
- Department of Chemistry and Biochemistry, University of Wisconsin-La Crosse, 1725 State Street, La Crosse, WI 54601, USA
| |
Collapse
|
18
|
Yurenko YP, Novotný J, Sklenář V, Marek R. Substituting CF2 for O4' in Components of Nucleic Acids: Towards Systems with Reduced Propensity to Form Abasic Lesions. Chemistry 2015; 21:17933-43. [PMID: 26493955 DOI: 10.1002/chem.201502977] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Indexed: 01/22/2023]
Abstract
Intrinsic structural features and energetics of nucleotides containing variously fluorinated sugars as potential building blocks of DNA duplexes and quadruplexes are explored systematically using the modern methods of density functional theory (DFT) and quantum chemical topology (QCT). Our results suggest that fluorination at the 2'-β or 2'-α,β positions somewhat stabilizes in vacuo the AI relative to the BI conformations. In contrast, substitution of the CF2 group for the O4' atom (O4'-CF2 modification) leads to a preference of the BI relative to AI DNA-like conformers. All the studied modifications result in a noticeable increase in the stability of the glycosidic bond [estimated by the relaxed force constants (RFC) approach], with particularly encouraging results for the O4'-CF2 derivative. Consequently, the O4'-CF2 modified systems are suggested and explored as promising scaffolds for the development of duplex and quadruplex structures with reduced propensity to form abasic lesions and to undergo DNA damage.
Collapse
Affiliation(s)
- Yevgen P Yurenko
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic).
| | - Jan Novotný
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic)
| | - Vladimir Sklenář
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic).,National Center for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic).,Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic)
| | - Radek Marek
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic). .,National Center for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic). .,Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic).
| |
Collapse
|
19
|
Alkorta I, Elguero J, Pérez-Torralba M, López C, Claramunt RM. A theoretical and experimental study of the NMR spectra of 4,5,6,7-tetrafluorobenzazoles with special stress on PCM calculations of chemical shifts. Magn Reson Chem 2015; 53:353-362. [PMID: 25615404 DOI: 10.1002/mrc.4203] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 12/04/2014] [Indexed: 06/04/2023]
Abstract
The chemical shifts and several (19)F-(19)F, (13)C-(19) F and (1)H-(19)F spin-spin coupling constants (SSCSs) of eight 4,5,6,7-tetraflurobenzazoles (three benzimidazoles, three benzimidazolinones and two indazoles) have been determined. The chemical shifts were discussed using gauge including atomic orbital-density functional theory calculations taking into account solvent effects (polarizable continuum model) and, for the solid state, hydrogen bonds (clusters up to three molecules).
Collapse
Affiliation(s)
- Ibon Alkorta
- Instituto de Química Médica, CSIC, Juan de la Cierva 3, E-28006, Madrid, Spain
| | | | | | | | | |
Collapse
|
20
|
Hermane J, Bułyszko I, Eichner S, Sasse F, Collisi W, Poso A, Schax E, Walter JG, Scheper T, Kock K, Herrmann C, Aliuos P, Reuter G, Zeilinger C, Kirschning A. New, non-quinone fluorogeldanamycin derivatives strongly inhibit Hsp90. Chembiochem 2015; 16:302-11. [PMID: 25572106 DOI: 10.1002/cbic.201402375] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 11/04/2014] [Indexed: 11/11/2022]
Abstract
Streptomyces hygroscopicus is a natural producer of geldanamycin. Mutasynthetic supplementation of an AHBA-blocked mutant with all possible monofluoro 3-aminobenzoic acids provided new fluorogeldanamycins. These showed strong antiproliferative activity and inhibitory effects on human heat shock protein Hsp90. Binding to Hsp90 in the low nanomolar range was determined from molecular modelling, AFM analysis and by calorimetric studies.
Collapse
Affiliation(s)
- Jekaterina Hermane
- Institute of Organic Chemistry, Center of Biomolecular Drug Research (BMWZ), Leibniz University Hannover, Schneiderberg 1B, 30167 Hannover (Germany)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
DeWitt JC, Copeland CB, Strynar MJ, Luebke RW. Perfluorooctanoic acid-induced immunomodulation in adult C57BL/6J or C57BL/6N female mice. Environ Health Perspect 2008; 116:644-50. [PMID: 18470313 PMCID: PMC2367677 DOI: 10.1289/ehp.10896] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Accepted: 02/06/2008] [Indexed: 05/02/2023]
Abstract
BACKGROUND Perfluorooctanoic acid (PFOA), an environmentally persistent compound of regulatory concern, has been reported to reduce antibody responses in mice at a single dose. OBJECTIVE The aim of this study was to evaluate PFOA effects on humoral and cellular immunity using standard assays for assessing immune function, and to derive dose-response data. METHODS C57BL/6J mice received 0 or 30 mg PFOA/kg/day for 10 days; half of the exposed groups were switched to vehicle and half continued on PFOA for five days. C57BL/6N mice received 0-30 mg/kg/day of PFOA in drinking water for 15 days. Mice were immunized with sheep red blood cells or sensitized to bovine serum albumin in Freund's complete adjuvant on day 10 of exposure; immune responses were determined 1 day post-exposure. RESULTS We found that 30 mg PFOA/kg/day given for 10 or 15 days reduced IgM synthesis; serum collected 1 day postexposure contained 8.4 x 10(4) or 2.7 x 10(5) ng PFOA/mL, respectively. IgM synthesis was suppressed at exposures > or = 3.75 mg PFOA/kg/day in a dose-dependent manner, and IgG titers were elevated at 3.75 and 7.5 mg PFOA/kg/day. Serum PFOA at 3.75 mg/kg/day was 7.4 x 10(4) ng/mL 1 day postexposure, or 150-fold greater than the levels reported in individuals living near a PFOA production site. Using a second-degree polynomial model, we calculated a benchmark dose of 3 mg/kg/day, with a lower bound (95% confidence limit) of 1.75 mg/kg/day. Cell-mediated function was not affected. CONCLUSIONS IgM antibodies were suppressed after PFOA exposure. The margin of exposure for reduced IgM antibody synthesis was approximately 150 for highly exposed human populations.
Collapse
Affiliation(s)
- Jamie C. DeWitt
- Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Carey B. Copeland
- Immunotoxicology Branch, Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory
| | - Mark J. Strynar
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA
| | - Robert W. Luebke
- Immunotoxicology Branch, Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory
- Address correspondence to R. Luebke, U.S. Environmental Protection Agency, MD B143-01, 109 TW Alexander Dr., Research Triangle Park, NC 27711 USA. Telephone: (919) 541-3672. Fax: (919) 541-3538. E-mail:
| |
Collapse
|