Three new taxane diterpenoids from the seeds of the Japanese yew, Taxus cuspidata

Three new and two known taxane diterpenoids were isolated from the seeds of the Japanese yew, Taxus cuspidata Sieb. et Zucc, and the structures were established as 1-deoxy-2-O-acetyltaxine B (1), 1-deoxy-2,9-O-diacetyl-10-deacetyltaxine B (2), 2-O-deacetyl taxine II (3), 1-deoxy-2,9-O-diacetyltaxine B (4), and 2'-hydroxytaxine II (5) respectively on the basis of spectroscopic analysis and comparison of their spectral data with taxine B, of which 1-3 are new.