A bioinspired naphthoquinone model of the quinones in photosynthetic reaction centers but bearing an intramolecular hydrogen-bonded carboxylic acid has been synthesized and characterized electrochemically, spectroscopically, and computationally to provide mechanistic insight into the role of proton-coupled electron transfer (PCET) of quinone reduction in photosynthesis. The reduction potential of this construct is 370 mV more positive than the unsubstituted naphthoquinone. In addition to the reversible cyclic voltammetry, infrared spectroelectrochemistry confirms that the naphthoquinone/naphthoquinone radical anion couple is fully reversible. Calculated redox potentials agree with the experimental trends arising from the intramolecular hydrogen bond. Molecular electrostatic potentials illustrate the reversible proton transfer driving forces, and analysis of the computed vibrational spectra supports the possibility of a combination of electron transfer and PCET processes. The significance of PCET, reversibility, and redox potential management relevant to the design of artificial photosynthetic assemblies involving PCET processes is discussed.
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http://dx.doi.org/10.1039/d4sc05277c | DOI Listing |
ACS Appl Mater Interfaces
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Key Laboratory of Industrial Ecology and Environment Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, PR China.
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View Article and Find Full Text PDFFood Chem
December 2024
College of Food Science, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing, Chongqing 400715, China; Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, Chongqing 400715, China. Electronic address:
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View Article and Find Full Text PDFJ Photochem Photobiol B
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College of Science, Northeast Forestry University, Harbin 150040, China. Electronic address:
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Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland; University of Basel, P.O. Box CH-4003, Basel, Switzerland. Electronic address:
For over three decades, praziquantel (PZQ) has been the mainstay chemotherapy for prevention and treatment of schistosomiasis. The excessive use of PZQ, coupled with the lack of advanced drug candidates in the current anti-schistosomiasis drug development pipeline, emphasizes the genuine need for new drugs. In the current work, we investigated the antischistosomal potential of a new series of compounds derived from the privileged benzimidazole scaffold, which exhibited low micromolar IC potency in the range of 1.
View Article and Find Full Text PDFChem Asian J
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