Design, synthesis and antifungal activity of novel α‐methylene‐γ‐butyrolactone derivatives containing benzothiophene moiety

Abstract

BackgroundThe discovery of agricultural fungicide candidates from natural products is one of the key strategies to develop environment friendly agricultural fungicides with high efficiency, high selectivity, and unique mechanisms of action. Based on previous work, a series of novel α‐methylene‐γ‐butyrolactone (MBL) derivatives containing benzothiophene moiety were designed and synthesized.ResultsThe majority of the proposed compounds displayed moderate to considerable antifungal efficacy against the tested pathogenic fungi and oomycetes, some exhibiting broad spectrum antifungal activity. Notably, compounds 2 (3‐F‐Ph) and 7 (4‐Cl‐Ph) showed excellent antifungal activity against R. solani with EC50 values of 0.94 and 0.99 mg/L, respectively, comparable to the commercial fungicide tebuconazole (EC50 = 0.96 mg/L), and also displayed significant inhibitory effects against V. mali with EC50 values of 2.26 and 1.67 mg/L, respectively, better than famoxadone and Carabrone. The in vivo protective and curative effects against R. solani of compound 2 were 57.2% and 53.7% at 100 mg/L, respectively, which were equivalent to tebuconazole (51.6% and 52.4%). Further investigations found that compound 2 altered the ultrastructure of R. solani cell, significantly increased the relative conductivity of the cells, and reduced the activity of complex III in a dose‐dependent manner. Molecular docking results showed that compound 2 matched well with the Qo pocket.ConclusionThe results revealed that MBL derivatives containing benzothiophene moiety are promising antifungal candidates and provide a new backbone structure for further optimization of novel fungicides.This article is protected by copyright. All rights reserved.

Synthesis of 2-Ethylhexyl 5-Bromothiophene-2-Carboxylates; Antibacterial Activities against Salmonella Typhi, Validation via Docking Studies, Pharmacokinetics, and Structural Features Determination through DFT

“…Thiophene-based compounds can be made quickly and have biological functions, which has provoked a lot of interest in their synthesis [4][5][6][7][8][9][10][11][12][13]. Their biological outcomes comprise antifungal, antiviral, antibacterial, anti-inflammatory, and cytotoxic characteristics [14,15]. Harit et al reported the antibacterial efficacy of thiophenebased compounds against Staphylococcus aureus, Escherichia coli, and Salmonella enterica subsp.…”