Five new diarylheptanoids from the rhizomes of Curcuma kwangsiensis and their antiproliferative activity.

Five new diarylheptanoids (1-5), along with nine known ones (6-14), were isolated from the rhizomes of Curcuma kwangsiensis. Their structures were established on the basis of spectroscopic analyses. Compounds 1-3 were cyclic diarylheptanoids rarely discovered from C. kwangsiensis. Of all the isolated compounds, compound 4 showed moderate antiproliferative activity on HH and HaCaT cells.