Ascandinines A–D, Indole Diterpenoids, from the Sponge-Derived Fungus Aspergillus candidus HDN15-152

• Main Authors: Guoliang Zhou (1433614), Chunxiao Sun (8633598), Xuewen Hou (3525002), Qian Che (725671), Guojian Zhang (1604386), Qianqun Gu (1433620), Chenguang Liu (1393930), Tianjiao Zhu (1433617), Dehai Li (1433623)
• Format: Other Non-Article Part of Journal/Newspaper
• Language: unknown
• Published: 2021
• Subjects: Biochemistry; Medicine; Microbiology; Neuroscience; Pharmacology; Biological Sciences not elsewhere classified; Chemical Sciences not elsewhere classified; Indole; motif; 7.8 μ M; H 1N activity; Ascandinine; compound 4; ring system; pentacyclic ring system; Diterpenoid; Sponge-Derived Fungus Aspergillus c.; indole diterpenoids; calculation; 2-; type; HL -60 cells; Antarctic sponge-derived fungus Asp.; NMR data; indole diterpenoid; 26 μ M; IC 50 value; oxabicyclo; configuration; cytotoxicity; biosynthetic considerations; Compound 3; anti-influenza virus; Antarctic; Antarc*
• Online Access: https://doi.org/10.1021/acs.joc.0c02575.s001

Four new indole diterpenoids, ascandinines A–D ( 1 – 4 ), were isolated from an Antarctic sponge-derived fungus Aspergillus candidus HDN15-152. Their structures, including absolute configurations, were established based on NMR data, computational calculations, and biosynthetic considerations. Ascandinine A ( 1 ) possesses an unprecedented 2-oxabicyclo[2.2.2]­octan-3-ol motif embedded in a pentacyclic ring system, while compounds 2 – 4 represent a rare type of indole diterpenoid featuring the 6/5/5/6/6/6/6-fused ring system. Compound 3 displayed anti-influenza virus A (H1N1) activity with an IC 50 value of 26 μM, while compound 4 showed cytotoxicity against HL-60 cells with an IC 50 value of 7.8 μM.