Antitumor actinopyranones produced by Streptomyces albus POR-04-15-053 isolated from a marine sediment

J Nat Prod. 2011 Jul 22;74(7):1590-6. doi: 10.1021/np200196j. Epub 2011 Jun 30.


Four new antitumor pyranones, PM050511 (1), PM050463 (2), PM060054 (3), and PM060431 (4), were isolated from the cell extract of the marine-derived Streptomyces albus POR-04-15-053. Their structures were elucidated by a combination of spectroscopic methods, mainly 1D and 2D NMR and HRESIMS. They consist of an α-methoxy-γ-pyrone ring containing a highly substituted tetraene side chain glycosylated at C-10 in the case of 1 and 4. Compounds 1 and 4 displayed strong cytotoxicity against three human tumor cell lines with GI₅₀ values in the submicromolar range, whereas 2 showed subnanomolar activity as an inhibitor of EGFR-MAPK-AP1-mediated mitogenic signaling, causing inhibition of EGF-mediated AP1 trans-activation and EGF-mediated ERK activation and slight inhibition of EGF-mediated JNK activation. Taken together, these results suggest that members of the pyranone family of compounds could be developed as potential antitumor agents.

MeSH terms

  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / isolation & purification*
  • Antineoplastic Agents / pharmacology*
  • Drug Screening Assays, Antitumor
  • ErbB Receptors / drug effects
  • Female
  • Geologic Sediments / microbiology
  • Humans
  • MAP Kinase Kinase 4 / drug effects
  • MAP Kinase Signaling System / drug effects
  • Marine Biology
  • Molecular Structure
  • Pyrones / chemistry
  • Pyrones / isolation & purification*
  • Pyrones / pharmacology*
  • Streptomyces / chemistry*
  • Transcription Factor AP-1 / drug effects


  • Antineoplastic Agents
  • Pyrones
  • Transcription Factor AP-1
  • ErbB Receptors
  • MAP Kinase Kinase 4