Vinmajorines C – E, Monoterpenoid Indole Alkaloids from Vinca major

Three new monoterpenoid indole alkaloids, vinmajorines C–E ( 1 – 3 ), along with 18 known analogues ( 4 – 21 ), were isolated from the whole plants of Vinca major. The new structures were elucidated as (5 α ,15 β ,16 R ,17 α ,19 β ,20 α ,21 β )‐10,17‐dimethoxy‐21‐methyl‐18‐oxa‐5,16‐cycloyohimban‐19‐ol ( 1 ), (5 α ,15 β ,16 R ,17 α ,20 α ,21 β )‐10‐methoxy‐21‐methyl‐18‐oxa‐5,16‐cycloyohimban‐17‐ol ( 2 ), and (5 α ,15 β ,16 R ,17 α ,20 α ,21 β )‐10‐methoxy‐21‐methyl‐18‐oxa‐5,16‐cycloyohimban‐17‐yl acetate ( 3 ), respectively, by extensive NMR and MS analysis and comparison with known compounds. Compounds 1 – 3 were evaluated for their cytotoxic activities against five human cancer cell lines, compounds 1 and 3 showing moderate cytotoxic activities.