Five compounds have been isolated from the heartwood of Cordyla africana and shown by chemical degradation, synthesis, and spectral considerations to be 2′,4′,5′,6,7-pentamethoxy-, 3′,4′,6,7-tetramethoxy-, 3′,6,7-trimethoxy-4′,5′-methylenedioxy-, and 2′,6,7-trimethoxy-4′,5′-methylenedioxy-isoflavone, together with 6,7-dimethoxy-3′,4′-methylenedioxyisoflavanone. 6,7-Dimethoxy-3′,4′-methylenedioxyisoflavone has been synthesised and reduced to the isoflavanone; the former is considered also to be present in the heartwood. The mass spectra of these and related isoflavones have been analysed and the presence of the 2′-methoxy-group is shown to influence the fragmentation pattern profoundly.