Two new diterpenes, neocaesalpin MR and minaxin C, from Caesalpinia minax

Two new cassane-type diterpenes, neocaesalpin MR (1) and minaxin C (2), were isolated from Caesalpinia minax HANCE. The structures of these compounds were elucidated by means of spectroscopic analysis. Among these isolated compounds, neocaesalpin MR showed mild activities toward HeLa and colon cancer (HCT-8) human cancer cell lines.