Novel anticancer agents, kayeassamins A and B from the flower of Kayea assamica of Myanmar

The CHCl3-soluble fraction of 70% EtOH extract of the flower of Kayea assamica completely killed human pancreatic PANC-1 cancer cells preferentially under nutrient-deprived conditions at 1 μg/mL. Bioassay-guided fractionation and isolation afforded two novel compounds, kayeassamins A (1) and B (2). Their structures were elucidated using extensive spectroscopic methods and the modified Mosher method. Each compound showed 100% preferential cytotoxicity (PC100) against PANC-1 cells under nutrient-deprived conditions at 1 μM. Furthermore, both compounds inhibited the migration of PANC-1 cells in the wound closure assay.