Four novel taxane diterpenes were isolated from the needles of the Japanese yew, Taxus cuspidata. Their structures were established as 1-hydroxy taxuspine C, 2α,7β,9α, 10β,13α-pentaacetoxy-5α-cinnamoyloxy-4β,20-epoxy- taxa-11-en-1β-ol, 2α,9α,10β,13α-tetraacetoxy-taxa-4(20), 11-dien-5α-ol and
Some non-taxol-type taxoids having neither an oxetane ring at C-4 and C-5 nor an N-acylphenyl-isoserine group at C-13, such as taxuspine C, 2'-desacetoxyaustrospicatine, and 2-desacetoxytaxinine J, which were isolated from the Japanese yew Taxus cuspidata, increased cellular accu-mulation of