A pair of new diastereomeric isoindolinone alkaloids, spirocollequins A and B, were isolated from an endophytic fungus, Colletotrichum boninense AM-12-2. Their structures are featuring a 4,5-dihydro-spiro[furan-2,1′-isoindolin]-3′-one core. Their structures were determined by 1D/2D NMR, the Mosher’s ester method, and DFT-GIAO NMR chemical shift calculations, coupled with advanced statistical procedures. Spirocollequins A and B exhibited in vitro antiplasmodial activity at the IC₅₀ (μM) values of 9.72 ± 0.61 and 4.71 ± 0.77, respectively.

中文翻译：

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Spirocollequins A和B，具有螺环异吲哚啉酮核心的新生物碱，来自Bonetense Colletotrichum AM-12-2

从内生真菌Bonetense AM-12-2中分离出一对新的非对映异构异吲哚啉酮生物碱A和B。它们的结构以4，5-二氢-螺[呋喃-2，1'-异吲哚啉] -3'-一个核为特征。它们的结构通过1D / 2D NMR，Mosher酯法和DFT-GIAO NMR化学位移计算以及先进的统计程序确定。螺旋螺菌素A和B在IC ₅₀（μM）值分别为9.72±0.61和4.71±0.77时表现出体外抗血浆活性。