Ophiobolin-Type Sesterterpenoids from the Mangrove Endophytic Fungus Aspergillus sp. ZJ-68

  • J Nat Prod. 2019 Aug 23;82(8):2268-2278. doi: 10.1021/acs.jnatprod.9b00462.
Runlin Cai  1 ,  Hongming Jiang  1 ,  Yaling Mo  1 ,  Huixian Guo  2 ,  Chunyuan Li  3 ,  Yuhua Long  2 ,  Zhenming Zang  1 ,  Zhigang She  1  4
Affiliations
  • 1. School of Chemistry , Sun Yat-sen University , Guangzhou 510275 , People's Republic of China.
  • 2. School of Chemistry and Environment , South China Normal University , Guangzhou 510006 , People's Republic of China.
  • 3. College of Materials and Energy , South China Agricultural University , Guangzhou 510642 , People's Republic of China.
  • 4. South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center , Guangzhou 510006 , People's Republic of China.
PMID: 31365251 DOI: 10.1021/acs.jnatprod.9b00462
Abstract

Eleven new ophiobolin-type sesterterpenoids, asperophiobolins A-K (1-11), along with 12 known analogues (12-23) were isolated from the cultures of the mangrove endophytic fungus Aspergillus sp. ZJ-68. The structures of the new compounds were elucidated through spectroscopic analyses, and their absolute configurations were assigned by a combination of Mo2(AcO)4-induced electronic circular dichroism spectra and quantum chemical calculations. Asperophiobolins A-D (1-4) represent the first examples possessing a five-membered lactam unit between C-5 and C-21 in ophiobolin derivatives. In the bioactivity assays, compounds 8-10 and 14-17 exhibited inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophage cells with IC50 values ranging from 9.6 to 25 μM, and compound 8 was found to show comparable inhibition of Mycobacterium tuberculosis protein tyrosine Phosphatase B with an IC50 value of 19 μM.