| Summary: | Ochrazepines A−D (<b>1</b>−<b>4</b>), four new conjugates dimerized from 2-hydroxycircumdatin C (<b>5</b>) and aspyrone (<b>6</b>) by a nucleophilic addition to epoxide, were isolated from the fermentation broth of the coral-associated <i>Aspergillus ochraceus</i> strain LCJ11-102. Their structures including absolute configurations were determined based on spectroscopic analysis and chemical methods. Compounds <b>1</b>−<b>4</b> were also obtained by the semisynthesis from a nucleophilic addition of 2-hydroxycircumdatin C (<b>5</b>) to aspyrone (<b>6</b>). New compound <b>1</b> exhibited cytotoxic activity against 10 human cancer cell lines while new compounds <b>2</b> and <b>4</b> selectively inhibited U251 (human glioblastoma cell line) and compound <b>3</b> was active against A673 (human rhabdomyoma cell line), U87 (human glioblastoma cell line), and Hep3B (human liver cancer cell line) with IC<sub>50</sub> (half maximal inhibitory concentration) values of 2.5−11.3 μM among 26 tested human cancer cell lines.
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