During our investigation on the endophytic fungi of Azadirachta indica, the strain YM 311593 was obtained from the fruit of the plant. The culture extract of the strain showed antifungal activities against four phytopathogenic fungi. Based on the morphological features and phylogenetic definition, the strain YM 311593 was identified as Paraconiothyrium sp. Four xanthones and one anthraquinone were obtained from the extract of the fermentation broth of the strain. They were characterized to be globosuxanthone A (1), vertixanthone (2), hydroxyvertixanthone (3), 3,8-dihydroxy-1-methy1-9H- xanthen-9-one (4), and danthron (5), respectively, by spectroscopic elucidation. Furthermore, the absolute configuration of 1 was deduced by X-ray diffraction analysis. Besides, compound 4 was firstly found from natural sources. The antifungal activities of compounds 1-5 towards four phytopathogens were assayed using broth microdilution method. Among them, globosuxanthone A (1) showed obvious antifungal activity towards Fusarium graminearum, Fusarium solani, and Botrytis cinerea with MIC values of 4, 8, and 16 μg/mL, respectively.

中文翻译：

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内生真菌Paraconionthyrium sp。产生的抗真菌黄嘌呤。YM 311593。

在我们调查印度印za的内生真菌的过程中，菌株YM 311593是从植物的果实中获得的。该菌株的培养物提取物显示出对四种植物病原真菌的抗真菌活性。根据形态特征和系统发育定义，菌株YM 311593被鉴定为副锥甲状腺菌。从该菌株的发酵液的提取物中获得了四种氧杂蒽酮和一种蒽醌。它们的特征分别为globosuxanthone A（1），vertixanthone（2），hydroxyvertixanthone（3），3,8-dihydroxy-1-methy1-9H-xanthen-9-one（4）和danthron（5），通过光谱分析。此外，通过X射线衍射分析推导了1的绝对构型。此外，化合物4是首先从天然来源中发现的。使用肉汤微稀释法测定化合物1-5对四种植物病原菌的抗真菌活性。其中，globosuxanthone A（1）对禾谷镰刀菌，茄镰刀菌和灰葡萄孢具有明显的抗真菌活性，MIC值分别为4、8和16μg/ mL。