Antineoplastic agents 596. Isolation and structure of chromomycin A5 from a Beaufort Sea microorganism

Abstract

A microorganism identified as Streptomyces sp. was isolated from a sedimentary specimen collected on the Beaufort Sea coast of Alaska. Fermentation scale-up and cancer cell line-guided separation of the constituents led to isolation and structural elucidation (high resolution MALDI-TOF mass and 2D NMR spectral analyses) of a diastereomer of chromomycin A2 (2) designated chromomycin A₅ (5). Chromomycin A₅ displayed very potent cancer cell growth inhibitory activity (reaching with MCF-7 breast cancer GI₅₀ 0.00073 μg mL⁻¹) against a mini-panel of murine and human cancer cell lines.