Fungal metabolites, asterric acid derivatives inhibit vascular endothelial growth factor (VEGF)-induced tube formation of HUVECs.

In the search for new naturally occurring anti-angiogenic compounds, we found that a culture broth of an unidentified fungal strain B90911 exerted inhibitory activity on capillary-like tube formation of human umbilical vein endothelial cells (HUVEC) in vitro. Four active compounds were isolated by bioassay-guided separation and their structures were identified to be sulochrin (1), methyl asterric acid (2), and two new asterric acid derivatives, 3-chloroasterric acid (3), and 3,5-dichloroasterric acid (4) by spectroscopic analyses. These compounds significantly inhibited the VEGF-induced tube formation of HUVEC, suggesting that asterric derivatives could be useful for further study as anti-angiogenic agents.