Heilaohu, the roots of Kadsura coccinea, has a long history of use in Tujia
ethnomedicine for the treatment of
rheumatoid arthritis and gastroenteric disorders, and a lot of work has been done in order to know the material basis of its pharmacological activities. The chemical investigation led to the isolation and characterization of three new (1⁻3) and twenty known (4⁻23)
lignans. Three new heilaohulignans A-C (1⁻3) and seventeen known (4⁻20)
lignans possessed
dibenzocyclooctadiene skeletons. Similarly, one was a diarylbutane (21) and two were spirobenzofuranoid
dibenzocyclooctadiene (22⁻23)
lignans. Among the known compounds, 4⁻5, 7, 13⁻15 and 17⁻22 were isolated from this species for the first time. The structures were established, using IR, UV, MS and NMR data. The absolute configurations of the new compounds were determined by circular dichroism (CD) spectra. The isolated
lignans were further evaluated for their cytotoxicity and
antioxidant activities. Compound 3 demonstrated strong cytotoxic activity with an IC50 value of 9.92 µM, compounds 9 and 13 revealed weak cytotoxicity with IC50 values of 21.72 µM and 18.72 µM, respectively in the HepG-2 human
liver cancer cell line. Compound 3 also showed weak cytotoxicity against the BGC-823 human
gastric cancer cell line and the HCT-116 human
colon cancer cell line with IC50 values of 16.75 µM and 16.59 µM, respectively. A chemiluminescence assay for
antioxidant status of isolated compounds implied compounds 11 and 20, which showed weak activity with IC50 values of 25.56 µM and 21.20 µM, respectively.