One new chromanone derivative, alterchromanone A (1), and four known curvularin-type macrolides (2–5) were isolated from the crude extract of the mangrove-derived endophytic fungus Alternaria longipes. Their structures were elucidated by MS and NMR spectroscopic analyses and by a comparison with data from the literature. The absolute configuration of 1 was assigned by combination of experimental and calculated electronic circular dichroism (ECD) spectra. Compound 1 exhibited 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity with an IC₅₀ value of 56.3 μg ml⁻¹. According to the structural features of these compounds, the plausible biosynthetic pathways of 1–5 were also proposed.

一个新的苯并二氢吡喃衍生物，alterchromanone A（1），和四个已知curvularin型大环内酯类（2 - 5）从红树林衍生内生真菌的粗提取物中分离烟草赤星病菌。它们的结构通过 MS 和 NMR 光谱分析以及与文献数据的比较来阐明。的绝对构型1，通过试验的和计算电子圆二色性（ECD）光谱的组合分配。化合物1表现出1,1-二苯基-2-苦基肼(DPPH)自由基清除活性，IC ₅₀值为56.3 μg ml ^-1. 根据这些化合物的结构特征，的似是而非的生物合成途径1 - 5还提出。