Planta Med 2012; 78 - PI26
DOI: 10.1055/s-0032-1320713

Ammosamide d from a marine-derived Streptomyces variabilis

E Pan 1, M Jamison 1, M Youssufuddin 2, J MacMillan 1
  • 1Department of Biochemistry, Division of Chemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd. Dallas, TX 75390
  • 2Center for Nanostructured Materials, University of Texas at Arlington, Arlington, TX

In our continuing efforts to search for natural products from marine bacteria with selective cytotoxicity against cancer cell lines, we obtained a series of fractions from the marine-derived Streptomyces variabilis (strain SNA-020) that exhibited modest selectivity and potency for the MiaPaca-2 pancreatic cancer cell line. Analysis of the active fractions by LC-UV-MS showed the presence of chlorine bearing molecules to ammosamide A and B, leading to the isolation of ammosamide D (1). It is the first example of an oxidized analog resulting in a 5,6-dioxo-5,6-dihydroquinoline ring system. Ammosamide D has modest cytotoxicity to the Mia-Paca2 pancreatic cancer cell line (IC50=3.2µM).