Asperlones A and B, dinaphthalenone derivatives from a mangrove endophytic fungus Aspergillus sp. 16-5C

Mar Drugs. 2015 Jan 13;13(1):366-78. doi: 10.3390/md13010366.

Abstract

Racemic dinaphthalenone derivatives, (±)-asperlone A (1) and (±)-asperlone B (2), and two new azaphilones, 6'-hydroxy-(R)-mitorubrinic acid (3) and purpurquinone D (4), along with four known compounds, (-)-mitorubrinic acid (5), (-)-mitorubrin (6), purpurquinone A (7) and orsellinic acid (8), were isolated from the cultures of Aspergillus sp. 16-5C. The structures were elucidated using comprehensive spectroscopic methods, including 1D and 2D NMR spectra and the structures of 1 further confirmed by single-crystal X-ray diffraction analysis, while the absolute configuration of 3 and 4 were determined by comparing their optical rotation and CD with those of the literature, respectively. Compounds 1, 2 and 6 exhibited potent inhibitory effects against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with IC50 values of 4.24 ± 0.41, 4.32 ± 0.60 and 3.99 ± 0.34 μM, respectively.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aspergillus / chemistry*
  • Bacterial Proteins / antagonists & inhibitors
  • Heterocyclic Compounds, 4 or More Rings / chemistry
  • Heterocyclic Compounds, 4 or More Rings / isolation & purification*
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Naphthols / chemistry
  • Naphthols / isolation & purification*
  • Protein Tyrosine Phosphatases / antagonists & inhibitors
  • X-Ray Diffraction

Substances

  • Bacterial Proteins
  • Heterocyclic Compounds, 4 or More Rings
  • MptpA protein, Mycobacterium tuberculosis
  • Naphthols
  • asperlone A
  • asperlone B
  • Protein Tyrosine Phosphatases