Cesium salts as superior catalysts for solvent-free modifications of biosourced pterolactam

γ-Lactam-Based Antifungal Compounds against the Wheat Pathogen Zymoseptoria tritici

As new environmentally friendly and effective antifungal agents are deeply needed, efficient ecofriendly strategies were designed to access two series of compounds inspired from natural γ-lactams. Designed compounds were fully characterized and evaluated as antifungal candidates against Zymoseptoria tritici, the main pathogen on wheat crops. The targeted derivatives were prepared from natural resources using green solvents, simple procedures, and limited purification steps. These bio-inspired compounds revealed as good candidates for further development of efficient crop protection products. Indeed, the HIT compounds exhibited IC₅₀ around 1 μg/mL and were more active than the references tebuconazole and bixafen towards some multidrug-resistant strains. Two dozen of derivatives have been obtained for each series and allowed to establish early structure-activity relationships useful for the development of next generation of γ-lactam derivatives with improved efficacy.

Design, synthesis and evaluation of hydrazine and acyl hydrazone derivatives of 5-pyrrolidin-2-one as antifungal agents

Twenty-eight 5-pyrrolidine-2-ones decorated by hydrazine or acyl hydrazones groups have been designed, synthesized and evaluated as antifungal agents on a panel of twelve fungal strains and three non albicans candida yeasts species which have demonstrated reduced susceptibility to commonly used antifungal drugs. Half of the target compounds exhibited good to high antifungal activities on at least one strain with MIC₅₀ lower than the control antifungal agent - hymexazol or ketoconazole. 5-Arylhydrazino-pyrrolidin-2-ones were found active and the -NH-NH- linker proved to be essential to maintain the antifungal potential. Compound 2a is a broad-spectrum antifungal, active on 60% of the tested strains. Replacing the hydrazine linker by an acylhydrazone one narrowed the spectrum of activity but pyroglutamylaryl hydrazones, mainly aromatic ones, exhibited good activity, adequate "fungicide-like" properties and were devoted of cytotoxicity.