Eleven novel diarylheptanoids and two unusual diarylheptanoid derivatives from the seeds of Alpinia blepharocalyx

An EtOH extract of the seeds of Alpinia blepharocalyx afforded 11 novel dia rylheptanoids, named deoxycalyxin A (1), epicalyxin F (2), calyxin K (3), e picalyxin K (4), calyxin I (5), epicalyxin I (6), calyxin J (7), epicalyxin J (8), and calyxin L (9), an epimeric mixture of calyxin M (10) and epical yxin M (11), and two unusual diarylheptanoid derivatives, named neocalyxins A (12) and B (13), together with four known calyxins, calyxins A (14), F ( 15), E (16), and G (17). Structures were elucidated by spectroscopic techni ques including 2D NMR spectroscopy. All compounds were examined for cytotox icity toward murine colon 26-L5 carcinoma and human HT-1080 fibrosarcoma ce lls. Diarylheptanoids 2, 3, and 5 were cytotoxic against both cell lines, w hile 4 and 6-8 were cytotoxic against human fibrosarcoma cells.