题目: Antifungal New Oxepine-Containing Alkaloids and Xanthones from the Deep-Sea-Derived Fungus Aspergillus versicolor SCSIO 05879

作者: Junfeng Wang, Weijun He,  Xiaolong Huang,  Xinpeng Tian, Shengrong Liao, Bin Yang, Fazuo Wang, Xiaojiang Zhou, Yonghong Liu*

刊物: Journal of Agricultural and Food Chemistry

年卷期页: 2016,64(14):2910-2916

摘要: Phytopathogenic fungi remain a continuous and huge threat in the agricultural fields. The agrochemical industry has made great development of the use of microbial natural products, which has been regarded as an effective strategy against phytopathogenic fungi. Antifungal bioassay-directed fractionation was used to isolate two new oxepine-containing alkaloids (1 and 2), two new 4-aryl-quinolin-2-one alkaloids (3 and 4), and four new prenylated xanthones (5−8) from the deep-sea-derived fungus Aspergillus versicolor SCSIO 05879. Extensive NMR spectroscopic analysis, quantum mechanical calculations, and X-ray single-crystal diffraction were used to elucidate their structures, including their absolute configurations. Versicoloids A and B, versicone A, and cottoquinazoline A showed antifungal activities against three phytopathogenic fungi. The antifungal activities of these bioactive compounds strongly depend on the fungal species. Especially versicoloids A and B showed strong fungicidal effect (MIC of 1.6 μg/mL) against Colletotrichum acutatum, compared with that of the positive control cycloheximide (MIC of 6.4 μg/mL). The results of antifungal experiments indicated that versicoloids A and B may be regarded as candidate agents of antifungal agrochemicals.