One new α-pyrone (nocapyrone R (1)), and three known γ-pyrones (nocapyrones B, H and L (2–4)) were isolated from the culture extract of a Nocardiopsis strain collected from marine sediment. Structures of these compounds were determined on the basis of spectroscopic data including NMR and MS. γ-Pyrones 2–4 were found to induce adiponectin production in murine ST-13 preadipocyte cells but the α-pyrone 1 had no activity. The absolute configuration of the anteiso-methyl branching in 4 was determined by HPLC comparison of a degraded product of 4 with standard samples as a 2:3 enantiomeric mixture of (R)- and (S)-isomers.
从海洋沉积物中采集的一种 Nocardiopsis 菌株的培养提取物中分离出了一种新的α-吡喃酮(nocapyrone R (1))和三种已知的γ-吡喃酮(nocapyrones B, H 和 L (2-4))。根据 NMR 和 MS 等光谱数据确定了这些化合物的结构。研究发现,γ-吡喃酮 2-4 能诱导小鼠 ST-13 前脂肪细胞产生脂肪生成素,但α-吡喃酮 1 没有活性。通过 HPLC 比较 4 的降解产物和标准样品,确定了 4 中的蚁异甲基分支的绝对构型,即 (R)- 和 (S)- 异构体的 2:3 对映异构体混合物。