Background: Downy mildew is one of the major fungi causing significant economic losses to crops. The resistance of this fungus to current fungicides is increasing and new fungicides with a unique mode of action are needed.
Objective: To find a novel pyrazole amide derivative as a potential fungicide.
Methods: A series of pyrazole-5-carboxamide derivatives containing a diaryl ether were designed and synthesized by the Intermediate derivatization method (IDM). Their fungicidal activities against Pseudoperonospora cubensis (P. cubensis, cucumber downy mildew) were evaluated in the greenhouse.
Results: Bioassays indicated that several compounds exhibited excellent fungicidal activity against P. cubensis in vivo. In particular, T24 (EC = 0.88 mg L) had the highest activity compared with Dimethomorph and Fluazinam and other analogues. The relationship between the activity and the structure of these derivatives was analyzed, and an accurate and reliable three-dimensional quantitative structure-activity relationship (3D-QSAR) model was established to determine that electrostatic and steric fields had important effects on the improvement of fungicidal activity.
Conclusion: The novel pyrazole-5-carboxamide derivative T24 can be considered a potential fungicide for P. cubensis control.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.2174/1570179420666230327145745 | DOI Listing |
Environ Sci Process Impacts
January 2025
Univ. Lille, CNRS, UMR 8522, Physico-Chimie des Processus de Combustion et de l'Atmosphère - PC2A, 59000 Lille, France.
Fenpyrazamine (FPA) is a widely used fungicide in agriculture to control fungal diseases, but its environmental degradation by oxidants and the formation of potential degradation products remain unexplored. This study investigates the oxidation of FPA by hydroxyl radicals (HO˙) using density functional theory (DFT) calculations at the M06-2X/6-311++G(3df,3pd)//M06-2X/6-31+G(d,p) level of theory. Three standard oxidation mechanisms, including formal hydrogen transfer (FHT), radical adduct formation (RAF), and single electron transfer (SET), were evaluated in the aqueous phase, with reaction kinetics analyzed over a temperature range of 283-333 K.
View Article and Find Full Text PDFJ Med Chem
January 2025
State Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals of Guizhou University, Guiyang 550025, China.
Though succinate dehydrogenase inhibitors (SDHIs) are quite successful in the modern agrochemical industry, the Fungicide Resistance Action Committee has classified the resistance risk as "medium to high". Structural analysis reveals that these antifungal chemotypes are highly conserved with amides as a consistent feature. This chemical factor may be a potential factor for the ever-increasing resistance risk.
View Article and Find Full Text PDFBMC Microbiol
December 2024
State Key Laboratory Incubation Base for Conservation and Utilization of Bio-Resource in Tarim Basin, Alar, Xinjiang Uygur Autonomous Region, 843300, China.
Background: Pear black spot is caused by Alternaria tenuissima. It is one of the diseases of concern limiting pear production worldwide. Existing cultivation methods and fungicides are not sufficient to control early blight.
View Article and Find Full Text PDFEnviron Health Perspect
December 2024
Division of Pharmacology & Toxicology, The University of Texas at Austin, Austin, Texas, USA.
Background: Endocrine-disrupting chemicals (EDCs) are exogenous chemical compounds that interfere with the normal function of the endocrine system and are linked to direct and inherited adverse effects in both humans and wildlife. Legacy EDCs such as polychlorinated biphenyls (PCBs) are no longer used yet remain detectable in biological specimens around the world; concurrently, we are exposed to newer EDCs like the fungicide vinclozolin (VIN). This combination of individuals' direct environmental chemical exposures and any heritable changes caused by their ancestors' chemical exposures leads to a layered pattern of both direct and ancestrally inherited exposures that might have cumulative effects over generations.
View Article and Find Full Text PDFEnviron Pollut
December 2024
Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, PR China. Electronic address:
The proliferation of weeds, pests, and plant diseases in crop cultivation has driven the increased application of herbicide lactofen, insecticide acetamiprid, and fungicide carbendazim, contributing to environmental pollution. Microorganisms are requently employed to remove pesticide residues from the environment. However, Liquid bacterial agents encounter difficulties in transportation and preservation during application and the current immobilized bacterial agents have a single degradation function.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!