Sixteen diterpenoids (1-16) including 10 new ones, pierisjaponins A-J (1-10), were isolated and identified from Pieris japonica, and their structures were classified into eight diverse carbon skeletons. Pierisjaponins A (1) and B (2) represent the first 1,5-seco-grayanane diterpenoid glucosides and
A total of fifteen grayanane diterpenoid glucosides including eight undescribed ones, pierisjaponosides A-H, were isolated from the leaves of Pieris japonica (Thunb.) D. Don ex G. Don (Ericaceae). Their structures were established by extensive spectros copic techniques including HRESIMS and NMR, as