Characterization of l‑Digitoxosyl-phenanthroviridin from <i>Streptomyces venezuelae</i> ISP5230

Abstract

The jadomycin-derived compound l-digitoxosyl-phenanthroviridin was isolated from fermentations of <i>Streptomyces venezuelae</i> ISP5230 grown in nutrient-deficient media with l-lysine as the sole nitrogen source. Structural elucidation was accomplished using a combination of high-resolution MS, LC-MS/MS, and 1D- and 2D-NMR. The compound was evaluated against the National Cancer Institute (NCI) 60 human tumor cell line screen in both the one-dose and five-dose screens, and cytotoxicity was compared to a small library of jadomycin analogues to probe the structure–activity relationship