Saccharothrixones A–D, Tetracenomycin-Type Polyketides from the Marine-Derived Actinomycete <i>Saccharothrix</i> sp. 10-10

Saccharothrixones A–C (<b>1</b>–<b>3</b>), three new aromatic polyketide <i>seco</i>-tetracenomycins, and saccharothrixone D (<b>4</b>), a new tetracenomycin analogue possessing opposite configurations at all of the stereogenic centers, were isolated from the marine-derived actinomycete <i>Saccharothrix</i> sp. 10-10. Compounds <b>1</b>–<b>3</b> represent the first examples of <i>seco</i>-tetracenomycins where the quinone ring B is cleaved and re-formed into a furanone ring. Their structures were elucidated by spectroscopic analyses and ECD calculations. The absolute configuration of <b>4</b> was confirmed by single-crystal X-ray diffraction analysis. Saccharothrixone D (<b>4</b>) showed <i>in</i> <i>vitro</i> cytotoxic activity against the HepG2 cancer cell line with an IC₅₀ value of 7.5 μM

Saccharothrixones A–D, Tetracenomycin-Type Polyketides from the Marine-Derived Actinomycete <i>Saccharothrix</i> sp. 10-10

Saccharothrixones A–C (<b>1</b>–<b>3</b>), three new aromatic polyketide <i>seco</i>-tetracenomycins, and saccharothrixone D (<b>4</b>), a new tetracenomycin analogue possessing opposite configurations at all of the stereogenic centers, were isolated from the marine-derived actinomycete <i>Saccharothrix</i> sp. 10-10. Compounds <b>1</b>–<b>3</b> represent the first examples of <i>seco</i>-tetracenomycins where the quinone ring B is cleaved and re-formed into a furanone ring. Their structures were elucidated by spectroscopic analyses and ECD calculations. The absolute configuration of <b>4</b> was confirmed by single-crystal X-ray diffraction analysis. Saccharothrixone D (<b>4</b>) showed <i>in</i> <i>vitro</i> cytotoxic activity against the HepG2 cancer cell line with an IC₅₀ value of 7.5 μM