Fiscpropionates A-F (1-6), six new polypropionate derivatives featuring an unusual long hydrophobic chain, were isolated from the deep-sea-derived fungus Aspergillus fischeri FS452. Their structures were elucidated on the basis of spectroscopic analysis, and the absolute configurations were determined by J-HMBC analysis, electronic circular dichroism (ECD) calculations, and the modified Mosher's method. This is the first discovery of polypropionates from marine-derived fungi, and compounds 4 and 5 represent the first examples of polypropionate derivatives containing a 3-hydroxypiperidin-2-one as part of an imide linkage. In addition, compounds 1-4 exhibited significant inhibitory activities against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with the IC50 values of 5.1, 12, 4.0, and 11 μM, respectively. Enzyme kinetic experiments suggested that they all acted through a noncompetitive mechanism. A preliminary structure-activity relationship is discussed.

中文翻译：

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来自深海衍生真菌费氏曲霉FS452的结核分枝杆菌蛋白酪氨酸磷酸酶B抑制活性的聚丙烯酸酯衍生物。

从深海真菌费氏曲霉FS452中分离出Fiscpropionates AF（1-6），这是六个具有异常长的疏水链的新型聚丙烯酸酯衍生物。在光谱分析的基础上阐明了它们的结构，并通过J-HMBC分析，电子圆二色性（ECD）计算和改进的Mosher方法确定了绝对构型。这是首次从海洋来源的真菌中发现聚丙烯酸酯，化合物4和5代表了包含3-羟基哌啶-2-酮作为酰亚胺键一部分的聚丙烯酸酯衍生物的第一个实例。此外，化合物1-4对结核分枝杆菌蛋白酪氨酸磷酸酶B（MptpB）表现出显着的抑制活性，IC50值分别为5.1、12、4.0和11μM。酶动力学实验表明它们都通过非竞争性机制起作用。讨论了初步的构效关系。