A chemical investigation of <i>Streptomyces</i> sp. Hu186 afforded two known quinone antibiotics, sarubicin A (<b>1</b>) and sarubicin B (<b>2</b>), together with three unusual variants, sarubicinols A-C (<b>3</b>-<b>5</b>), and two new 1,4-naphthoquinone metabolites, sarubicin B<sub>1</sub> (<b>6</b>) and sarubicin B<sub>2</sub> (<b>7</b>). Compounds <b>3</b>-<b>5</b> possess a rare 2-oxabicyclo [2.2.2] substructure and a benzoxazole ring system. Their structures were elucidated using 1D and 2D nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry data. The absolute configurations of the side-chain moieties in <b>4</b> and <b>5</b> were solved by electronic circular dichroism calculations. Compounds <b>1</b>-<b>7</b> showed moderate cytotoxic activity against four tumor cell lines.