Isolation and characterization of a new diketopiperazine from <i>Cephalotrichum</i> sp. RD-ZLM03 isolated in Jinlun cave

A new diketopiperazine, spirotryprostatin C (<b>1</b>), as well as nine known compounds (<b>2</b>–<b>10</b>), were isolated from the fermentation broth of the karst cave derived fungus <i>Cephalotrichum</i> sp. RD-ZLM03. Their structures were determined based on spectroscopic and X-ray diffraction analysis. Compounds <b>2</b>, <b>4</b>, <b>5</b>, <b>6</b>, <b>8</b>, <b>9</b>, and <b>10</b> showed significant proangiogenic activities at the concentration of 25 μM in the zebrafish model.