Three new indole diterpenoids from <i>Aspergillus aculeatus</i> KKU-CT2
Boonyanoot Chaiyosang, Kwanjai Kanokmedhakul, Natanong Yodsing, Sophon Boonlue, Jian-Xiong Yang, Yan Alexander Wang, Raymond J. Andersen, Jantana Yahuafai, Somdej Kanokmedhakul
Abstract
Three new indole diterpenoids, aculeatupenes A–C (1–3), together with four known compounds (4–7), were isolated from the mycelium of Aspergillus aculeatus KKU-CT2. Their structures were established by spectroscopic evidence and absolute configurations of 1–3 were determined by comparison of their experimental and calculated ECD spectra. Compounds 1, 2, and emindole SB (4) showed weak cytotoxicity against HelaS3, KB, HepG2, MCF-7, and A549 cancer cell lines with IC50 values in the range of 11.12–67.81 μM. Compound 3 showed weak cytotoxicity against HelaS3 cell lines with an IC50 value of 17.48 μM but non-cytotoxicity against Vero cell line. In addition, compound 1 exhibited weak antibacterial activity against Bacillus cereus.