Scapiformolactones A-I: Germacrane sesquiterpenoids with an unusual Δ3-15,6-lactone moiety from Salvia scapiformis

Nine germacrane sesquiterpenoids (1-9) with an unusual Δ3-15,6-lactone moiety and one known seco-germacrane sesquiterpenoid were isolated from the whole plants of Salvia scapiformis. Six germacrane 6,15-diol derivatives (11-16) were obtained by chemical transformation. Their structures were elucidated, and their in vitro cytotoxicity against five human cancer cell lines, as well as in vitro immunomodulatory effects on T and B cells were evaluated.