Cytotoxic polyacetylenes isolated from the roots and rhizomes of Notopterygium incisum

Phytochemical investigation on the roots and rhizomes of Notopterygium incisum led to the isolation of a new polyacetylene, notopolyenol A (1), along with thirteen known analogues (2-14). Their structures were elucidated by extensive analyses of NMR and HRMS data, and the absolute configuration of 1 was unambiguously determined as 3R by comparison of its retention time and ECD curve with those of synthetic enantiomers (-)-1 and (+)-1, whose absolute configurations were established by using the modified Mosher's method. Subsequent activity screening revealed that (3S)-1 exhibited the most significant cytotoxicity against MCF-7, H1299, and HepG2 cancer cells with IC₅₀ values of 1.3 μmol/L, 0.6 μmol/L and 1.4 μmol/L, respectively.