Three simaroubolides, glaucarubolone (1), holacanthone (2), and isobrucein A (3) were found to be responsible for the cytotoxic and antileukemic activities observed for extracts of the wood stem, stem bark, and twigs of Soulamea soulameoides. Other cytotoxic constituents isolated include a coumarinolignan cleomiscosin A (4) and the hydroxy canthin-6-one derivative 5. Picrasin B (6) was also obtained, but was not active.