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. Epub 2019 Jul 31.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aspergillus / chemistry*
  • Mice
  • RAW 264.7 Cells
  • Rhizophoraceae / microbiology*
  • Sesterterpenes / isolation & purification*
  • Sesterterpenes / pharmacology

Substances

  • Sesterterpenes
  • ophiobolins