Antartin, a Cytotoxic Zizaane-Type Sesquiterpenoid from a Streptomyces sp. Isolated from an Antarctic Marine Sediment

Abstract

Antartin (<b>1</b>), a new zizaane-type sesquiterpene, was isolated from <i>Streptomyces</i> sp. SCO736. The chemical structure of <b>1</b> was assigned from the interpretation of 1D and 2D NMR in addition to mass spectrometric data. The relative stereochemistry of <b>1</b> was determined by analysis of NOE data, while the absolute stereochemistry was decided based on a comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Antartin (<b>1</b>) showed cytotoxicity against A549, H1299, and U87 cancer cell lines by causing cell cycle arrest at the G1 phase.