Alkaloids and styryllactones from the leaves of Goniothalamus tamirensis

Abstract Three new compounds, goniotamirine (1) , goniotamiric acid (2) , and 3,5-demethoxypiperolide (3) were isolated from the leaves of Goniothalamus tamirensis (Annonaceae), together with sixteen known compounds, (−)- N -nornuciferine (4) , (−)-norisocorydine (5) , (−)-isocorydine (6) , (−)-3-hydroxynornuceferine (7) , (−)- O -methylisopiline (8) , (−)-anonaine (9) , (−)-roemerine (10) , (−)-roemeroline (11) , (−)-boldine (12) , glaunine (13) , liriodenine (14) , 9-deoxygoniopypyrone (15) , 8-epi-9-deoxygoniopypyrone (16) , 8-epi-9-deoxygoniopypyrone acetate (17) , goniodiol (18) and goniothalamin (19) . The structures were established from spectral analysis, including mass spectrometry and 2D-NMR. The absolute configuration of 1 was determined from analysis of its MTPA amide derivatives. The cytotoxicity of all isolates was evaluated against KB cells. Only compound 4 ( N -nornuciferine) showed a moderate activity with an IC 50 value of 12 μg/mL.