Talaroketals A and B, unusual bis(oxaphenalenone) spiro and fused ketals from the soil fungus Talaromyces stipitatus ATCC 10500

Org Biomol Chem. 2016 Mar 7;14(9):2691-7. doi: 10.1039/c5ob02657a.

Abstract

Two novel oxaphenalenone dimers, talaroketals A () and B (), were isolated from the soil fungus Talaromyces stipitatus. Their structures and absolute configurations were determined on the basis of spectroscopic analyses, X-ray diffraction experiments and electronic circular dichroism. Compound () features a rare benzannulated 5,6-spiroketal ring system within the dimeric bis(oxaphenalenone) skeleton while the parent compound () harbors a fused bicyclic furano-pyran moiety. These two compounds may biogenetically result from the reaction of duclauxin with a dihydrofuran derivative of botryodiplodin. Additionally, talaroketals A () and B () display modest antimicrobial activity against Staphylococcus aureus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Heterocyclic Compounds, 4 or More Rings / chemistry
  • Heterocyclic Compounds, 4 or More Rings / isolation & purification*
  • Models, Molecular
  • Molecular Conformation
  • Spiro Compounds / chemistry*
  • Talaromyces / chemistry*

Substances

  • Heterocyclic Compounds, 4 or More Rings
  • Spiro Compounds
  • talaroketal A
  • talaroketal B