Vibsanoids A–D, four new subtypes of vibsane diterpenoids with a distinctive tricyclo[8.2.1.02,9]tridecane core fromViburnum odoratissimum

Four highly rearranged tetranorvibsane-type diterpenoids, vibsanoids A–D, with an unprecedented tricyclo[8.2.1.0 2,9 ]tridecane skeleton were isolated from Viburnum odoratissimum .