C-7 oxygenated coumarins from the fruits of Micromelum minutum.

A new 7-oxygenated coumarin, 7-demethylmurralonginol isovalerate (1), and a new natural product, murralonginol (2), together with seven known 7-oxygenated coumarins, murralonginol isovalerate (3), murralongin (4), micromelin (5), scopoletin (6), microminutin (7), murrangatin (8), and minumicrolin (9), were isolated from the fruits of Micromelum minutum. The structures of these compounds were established on the basis of their 1D and 2D NMR spectroscopic data. Among these isolates, compounds 2 and 4 - 9 exhibited cytotoxicity against cholangiocarcinoma cell line, KKU-100.