Four New C9 Metabolites from the Sponge-Associated Fungus Gliomastix sp. ZSDS1-F7-2

作者：Jun Zhang, Zhiqiang Yang, Yan Liang, Liping Zhong, Huiting Lin, Balian Zhong, Liangchun Li, Shi‐Hai Xu, Yonghong Liu · 发表于：Marine Drugs · 年份：2018 · DOI：10.3390/md16070231 · 被引用次数：3 · 研究领域：Microbial Natural Products and Biosynthesis、Marine Sponges and Natural Products、Fungal Biology and Applications

Four new structurally related metabolites, one γ-lactone named gliomasolide F (1), one δ-lactone named gliomasolide G (2), and two medium-chain fatty acids named gliomacids A–B (3–4), each containing nine carbons in total, were identified from the sponge-associated fungus Gliomastix sp. ZSDS1-F7-2. The planar chemical structures of these novel C9 metabolites were elucidated by nuclear magnetic resonance (NMR) spectroscopic methods, in connection with the analysis of high-resolution mass spectrometry (HRMS) and infrared (IR) data. The absolute configuration of 1, was determined by comparisons of experimental circular dichroism (CD) and optical rotation (OR) value with corresponding ones computed by quantum chemistry. The relative configuration of 2 was determined by the Nuclear Overhauser effect spectroscopy (NOESY) spectrum, while its absolute configuration was tentatively determined in view of the biogenetic and biosynthetic relationships between 1 and 2. Compounds 3–4, originally as an inseparable mixture, were successfully isolated after chemical modifications. The stereo-chemistries of compounds 3–4 were assumed by comparison of 13C NMR with those of the similar moiety reported in literature, in addition to the biogenetic and biosynthetic relationships with 1. The plausible biosynthetic relationships among these four C9 metabolites were supposed. Biologically, compounds 1–4 showed no cytotoxic effect against HeLa cell line at concentrations up to 25 μg/mL, while 1 exhibit...