Polyacetylenes from Bupleurum longiradiatum.

Eight new polyacetylenes (1-8) and six known polyacetylenes were isolated from the entire parts of Bupleurum longiradiatum, a poisonous plant. The structures of the new compounds were determined by spectroscopic data interpretation. The absolute configuration of the known compound bupleurotoxin (9) was established by the modified Mosher's method. All isolates were also tested for their cytotoxicity against a human leukemia cell line (HL-60).