Asperunguisins A-F, Cytotoxic Asperane Sesterterpenoids from the Endolichenic Fungus Aspergillus unguis

J Nat Prod. 2019 Jun 28;82(6):1527-1534. doi: 10.1021/acs.jnatprod.8b01066. Epub 2019 May 22.

Abstract

Six new asperane-type sesterterpenoids, asperunguisins A-F (1-6), were isolated from the endolichenic fungus Aspergillus unguis, together with a known analogue, aspergilloxide (7); these are rare asperane-type sesterterpenoids, characterized by a unique hydroxylated 7/6/6/5 tetracyclic system. The structures of asperunguisins A-F (1-6) were elucidated on the basis of spectroscopic methods (NMR and HRESIMS), X-ray single-crystal diffraction analysis, ECD calculations, and biogenetic considerations. Asperunguisin C (3) showed cytotoxicity against the human cancer cell line A549 with an IC50 value of 6.2 μM. Further investigation revealed that the observed cell death was a result of G0/G1 cell cycle arrest via DNA damage followed by cellular apoptosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • A549 Cells / chemistry
  • A549 Cells / drug effects*
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Aspergillus / chemistry*
  • Crystallography, X-Ray
  • Fungi / chemistry*
  • Humans
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Sesterterpenes / chemistry*
  • Sesterterpenes / isolation & purification
  • Sesterterpenes / pharmacology*

Substances

  • Antineoplastic Agents
  • Sesterterpenes