Two new isopimarane diterpenoids, xylabisboein A (1) and B (2), as well as three known secondary metabolites (i.e., (−)-5-methylmellein (3), mellein-5-carboxylic acid (4) and ergosterol peroxide (5)), were isolated from a solid culture of the endophytic fungus Xylaria sp. SNB-GTC2501. The structures were elucidated by spectroscopic analysis and the absolute configuration of xylabisboein A (1) was determined by X-ray crystallographic analysis. All of the compounds were tested for their antimicrobial and cytotoxic activities.

中文翻译：

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来自内生真菌Xylaria sp。的两种新的异pimarane二萜。SNB-GTC2501

两种新的异pimarane二萜类化合物，木糖脂A（1）和B（2），以及三种已知的次生代谢产物（即（-）-5-甲基海藻油（3），Mellein-5-羧酸（4）和麦角固醇过氧化物（ 5）），是从内生真菌Xylaria sp。的固体培养物中分离得到的。SNB-GTC2501。通过光谱分析阐明了结构，并通过X射线晶体学分析确定了木糖脂原A（1）的绝对构型。测试所有化合物的抗微生物和细胞毒性活性。