Glasesterterpenoids A−C: three sesterterpenoids with 7-cyclohexyldecahydronaphthalene carbon skeleton isolated from the root of Lindera glauca

Three novel sesterterpenoids glasesterterpenoids A−C (1−3), featuring an unprecedented 7-cyclohexyldecahydronaphthalene carbon skeleton, were isolated from the root of Lindera glauca (L. glauca). Their structures were elucidated by quantum chemical calculations and spectroscopic methods. The biogenetic pathway for 1−3 is proposed. In the bioassay, glasesterterpenoid C exhibited DNA topoisomerase 1 (Top1) inhibitory activity compared with the positive control, camptothecin. These findings represent the first examples of sesterterpenoids with a 7-cyclohexyldecahydronaphthalene carbon skeleton from the root of L. glauca.