Design, synthesis, and antifungal activity evaluation of novel 2-cyano-5-oxopentanoic acid derivatives as potential succinate dehydrogenase inhibitors

In Pursuit of Lead Innovation: Pharmaceutically Important and Distinct Amide-Free Succinate Dehydrogenase Inhibitors

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. Introducing new antifungal structures or models may be a potent method to tackle this and find new bioactive compounds. In this Perspective, the recent progress in SDHIs without amide functionality from either synthetic endeavors or natural sources is showcased, focusing on their biological activities and a brief introduction of their mechanism. Synthetic advances in complex natural products are discussed, aiming to inspire new pharmaceutical discoveries and efficient synthesis methods. The challenges and strategies for the development of SDHIs are also discussed. This may offer insights for developing new SDHIs or chemical entities to combat the increasing resistance to commercial agrochemicals.

Comprehensive Overview of Carboxamide Derivatives as Succinate Dehydrogenase Inhibitors

Up to now, a total of 24 succinate dehydrogenase inhibitors (SDHIs) fungicides have been commercialized, and SDHIs fungicides were also one of the most active fungicides developed in recent years. Carboxamide derivatives represented an important class of SDHIs with broad spectrum of antifungal activities. In this review, the development of carboxamide derivatives as SDHIs with great significances were summarized. In addition, the structure-activity relationships (SARs) of antifungal activities of carboxamide derivatives as SDHIs was also summarized based on the analysis of the structures of the commercial SDHIs and lead compounds. Moreover, the cause of resistance of SDHIs and some solutions were also introduced. Finally, the development trend of SDHIs fungicides was prospected. We hope this review will give a guide for the development of novel SDHIs fungicides in the future.