Anti-Staphylococcal Calopins from Fruiting Bodies of Caloboletus radicans

J Nat Prod. 2018 Feb 23;81(2):400-404. doi: 10.1021/acs.jnatprod.7b00525. Epub 2018 Jan 30.

Abstract

Three new and seven known calopins were isolated from Caloboletus radicans. The structures of the new cyclocalopins, 8-deacetylcyclocalopin B (1), cyclocalopin A-15-ol (2), and 12,15-dimethoxycyclocalopin A (3), were mainly elucidated by NMR and MS data analysis. The stereochemistry of 1-3 was assigned based on NOE correlations and coupling constants and by comparison of their CD spectra with those of similar known calopins. While 1-10 were inactive against two cancer cell lines, they displayed anti-staphylococcal activity against methicillin-resistant Staphylococcus aureus strains (MRSA) with MIC values of 16-256 μg/mL. Moreover, some calopins were active against the fish pathogen Enterococcus faecalis F1B1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agaricales / chemistry
  • Anti-Bacterial Agents / chemistry*
  • Cell Line, Tumor
  • Enterococcus faecalis / drug effects
  • Fruiting Bodies, Fungal / chemistry*
  • Hep G2 Cells
  • Humans
  • Methicillin-Resistant Staphylococcus aureus / drug effects*
  • Microbial Sensitivity Tests / methods
  • Staphylococcal Infections / drug therapy

Substances

  • Anti-Bacterial Agents