LAUSR

Abstract A new 3,4- seco -27-norlanostane triterpene, ganoboninketal D ( 1 ), a new lanostane, (24 S )-3-oxo-7α,24,25-trihydroxylanosta-8-ene ( 2 ), together with six known lanostanes ( 3 – 8 ), were isolated from cultivated fruiting bodies of the basidiomycete Ganoderma orbiforme . The structures were elucidated on the basis of NMR spectroscopic and mass spectrometry data, and the structures 1 and 2 were further confirmed by chemical correlations to ganoboninketal C and ganodermanondiol, respectively. All isolated compounds were inactive in the antitubercular and antimalarial activity assays against Mycobacterium tuberculosis H37Ra and Plasmodium falciparum K1, respectively, except that compound 8 exhibited weak antitubercular activity (MIC 50 μg/ml).