[Studies on the alkaloids of Cephalotaxus. VII. Structures and semi-synthesis of two anticancer cephalotaxine esters].

Two new alkaloids, namely neoharringtonine (1) and anhydroharringtonine (2) with significant antileukemic activity were isolated from Cephalotaxus fortunei Hook f.. Their structures have been established by spectral analyses and semi-synthesis. Seven known alkaloids, deoxyharringtonine (3), isoharringtonine (4), isocephalotaxinone (5), acetylcephalotaxine (6), cephalotaxine (7), harringtonine (8) and homoharringtonine (9), were also isolated and identified.