Unusual cyclolanostanes from leaves of Pandanus boninensis

Two unusual triterpenoids, (24S)-24-methyl-25,32-cyclo-5α-lanosta-9(11)-en-3β-ol and (24S)-24-methyl-25,32-cyclo-cycloartane-3β-ol, were isolated from leaves of Pandanus boninensis. Their structures were established on the basis of spectroscopic methods and X-ray analysis.