A protostane and two lanostanes from the bark of Garcinia ferrea

A new protostane, (22Z,24E)-3-oxoprotosta-12,22,24-trien-26-oic acid (1), two novel lanostane lactones, garciferolides A (2) and B (3), along with dulxanthone A, 6-hydroxy-1,5-dimethoxyxanthone and 2-hydroxyxanthone, were obtained from the bark of Garcinia ferrea. Their structures were elucidated using spectroscopic methods, mainly 1-D and 2-D NMR.