Syntheses of C18 dibenzocyclooctadiene lignan derivatives as anti-HBsAg and anti-HBeAg agents Original Research Article

(+)-Gomisin K3 (1) and kadsurarin (2) were isolated from Schizandra arisanensis and Kadsura matsudai, respectively, and a series of C18 dibenzocyclooctadiene lignan analogues (5–20) derived from 1 and 2 were synthesized. Esterified derivatives of 1 and 2 were evaluated for inhibitory activity against human type B hepatitis with surface antigen (HBsAg) and e antigen (HBeAg). Most of the analogues (5–8, 10, 12–13) derived from 1 exhibited higher anti-HBsAg effects and lower toxicity, and 6, 7, 8 and 12 also showed higher anti-HBeAg activity. Among these active C18 dibenzocyclooctadiene lignan analogues, the lignan with a but-3-enoyl group (6) exhibited the most active inhibition.