A DNA-based artificial metalloenzyme (ArM) consisting of a copper(II) complex of 4,4'-dimethyl-2,2'-bipyridine (dmbipy-Cu) bound to double-stranded DNA (dsDNA) as short as 8 base pairs with only 2 contiguous central pairs (G for guanine and C for cytosine) catalyzes the highly enantioselective Diels-Alder reaction, Michael addition, and Friedel-Crafts alkylation in water. Molecular simulations indicate that these minimal sequences provide a single site where dmbipy-Cu is groove-bound and able to function as an enantioselective catalyst. Enantioselective preference inverts when d-DNA is replaced with l-DNA. When the DNA is conjugated to a hydrophobic tail, the obtained ArMs exhibit enantioselective performance in a methanol-water mixture superior to that of non-amphiphilic dsDNA, and dsDNA-amphiphiles with more complex G•C-rich sequences.
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http://dx.doi.org/10.1021/jacsau.1c00513 | DOI Listing |
Chirality
January 2025
Department of Pesticide Science, College of Plant Protection, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing Agricultural University, Nanjing, China.
Chiral pesticides often undergo enantioselective degradation during food fermentation. In this study, the enantioselective fates of seven chiral pesticides during processing of wine and rice wine were investigated. The results revealed that R-metalaxyl, R-mefentrifluconazole and S-hexaconazole were preferentially degraded during wine processing with EF values of 0.
View Article and Find Full Text PDFJ Agric Food Chem
November 2024
Department of Pesticide Science, College of Plant Protection, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing Agricultural University, Nanjing 210095, China.
In this study, the nuarimol enantiomers were successfully baseline separated with Rs 1.70 by ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The absolute configurations of the nuarimol enantiomers were confirmed as -(+)-nuarimol and -(-)-nuarimol.
View Article and Find Full Text PDFJ Agric Food Chem
November 2024
College of Plant Protection, Nanjing Agriculture University, Nanjing 210095, China.
Metolachlor, the chiral herbicide, inhibits the very-long-chain fatty acid (VLCFA) synthesis; elucidating the enantioselectivity between - and -metolachlor in the toxicological difference will facilitate the understanding of the site of action. We found that the endogenous accumulation of C22 VLCFAs decreased in both -/-metolachlor -treated plants by 6, 12, and 24 h after treatment, with more significant reduction in the isomer group. Gene expression of glutathione -transferase members were obviously induced upon treatments with or isomer; both OsGSTU1 and OsGSTU4 can metabolize metolachlor effectively, with isomer as the preference by directly catalyzing the conjugation between -metolachlor and glutathione.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing 210095, China. Electronic address:
Fenpropidin (FPD), a widely utilized chiral fungicide, has been detected in aquatic environments. This study systematically evaluated the bioaccumulation, depuration, biotransformation, and sensitive biomarkers of FPD enantiomers in zebrafish to assess their environmental risks. Compared with S-FPD, R-FPD demonstrated a higher rate of enrichment and an increased level of bioaccumulation.
View Article and Find Full Text PDFOrg Lett
September 2024
Department of Chemical Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8550, Japan.
We have achieved the enantioselective synthesis of highly strained, substituted ,,,-tetraphenylenes (≤98% ee) via the cationic Rh(I)/()-H-BINAP complex-catalyzed chemo-, regio-, and enantioselective intermolecular cross-[2+2+2] cycloaddition of teraryl diynes with dimethyl acetylenedicarboxylate. X-ray crystallographic analyses demonstrate the highly bent structures of the -substituted benzene moieties, and density functional theory calculations reveal the large local strain of the paraphenylene unit. H nuclear magnetic resonance analyses and theoretical calculations elucidate the stereoisomerism, indicating that the nonrotatable -disubstituted biphenyl structure results in and isomers.
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