Design, Synthesis and Antifungal Activities of 6‐Substituted 3‐Butylphthalide Derivatives against Phytopathogenic Fungi

Abstract

In order to discover novel potential antifungal agents, a series of 6-substituted 3-butylphthalide derivatives were designed, synthesized and evaluated for their antifungal activities against nine phytopathogenic fungi. Preliminary bioassay tests showed that five 3-butylphthalide derivatives exhibited more potent antifungal activities than hymexazol at the concentration of 50 μg/mL. Especially, 3-butyl-6-nitro-2-benzofuran-1(3H)-one and 3-butyl-6-hydroxy-5-nitro-2-benzofuran-1(3H)-one had significant fungicidal activity against some phytopathogenic fungi. The EC 50 of 3-butyl-6-nitro-2-benzofuran-1(3H)-one against FS, FO and FG were 6.6, 9.6 and 16.0 μg/mL, respectively. The EC 50 of 3-butyl-6-hydroxy-5-nitro-2-benzofuran-1(3H)-one against BC, PO, VM, SS and AS were 6.3, 5.9, 10.0, 4.5 and 8.4 μg/mL, respectively. The preliminary structure-activity relationships (SARs) of all target compounds were also investigated.

Natural Products‐Based Fungicides: Synthesis and Antifungal Activity against Plant Pathogens of 2H‐Chromene Derivatives

“…The antifungal activities of the target compounds were tested by poisoned food technique as the methods reported in our previous work [8,11] . ( Supporting Information )…”

“…Encouraged by above mentioned results and in continuation of our program aimed at the discovery and development of high‐efficacy and broad‐spectrum antifungal candidates, [9–13] herein we have designed and synthesized four series of 2 H ‐chromene derivatives as potential fungicides. As shown in Figure 2, firstly, in order to explore the electronic effects and space effects on the antifungal activity, compounds 1a – y containing various substituted on the chromene skeleton were designed by the principle of homologue derivation.…”

Design, Synthesis and in Vitro Antifungal Mechanism of Novel Phenylalanine Derivatives

“…In Vitro Antifungal Activity Evaluation [36] The fungicidal activities of G 1 -G 28 were tested in vitro against six plant pathogenic fungi (T. cucumeris, G. zeae, B. dothidea, S. sclerotiorum, G. saubinetii, and A. solani) using a mycelial growth inhibition method. The preliminary activity screening concentration of the target compounds was 100 μg/mL.…”

Unexpected Formation of 4-[(1-Carbamoyl-3-oxo-1,3-dihydro-2-benzofuran-1-yl)amino]benzoic Acid from 4-[(3-Amino-1-oxo-1H-2-benzopyran-4-yl)amino]benzoic Acid

“…Isobenzofuranones (Isobenzofuran-1(3H)-ones), commonly named as phthalides, are considered to be privileged structures in organic, biological, and medicinal chemistry. Specifically, those nuclei have exhibited a wide variety of biological activities, such as herbicidal 1 [11,12], antioxidant 2 [13,14], anti-rotavirus 3 [15], anti-inflammatory 4 [16], antibacterial 5 [17], antifungal 6 [18,19], as well as antileishmanial [20] activities (Figure 1), deriving from natural or synthetic products.…”