A New Megastigmane Palmitate and a New Oleanane Triterpenoid from Aster yomenaMakino

Abstract A new megastigmane palmitate, 9‐oxomegastigm‐5(13)‐ene‐2 β ‐palmitate ( 1 ), and a new oleanane triterpenoid, (3 β )‐3,23,28‐trihydroxyolean‐12‐en‐11‐one ( 2 ), together with three known oleanane‐type triterpenoids, β ‐amyrin ( 3 ), erythrodiol ( 4 ), and (3 β )‐olean‐12‐ene‐3,23,28‐triol ( 5 ), were isolated from the aerial parts of Aster yomena (Asteraceae). Their structures were identified based on 1D‐ and 2D‐NMR analysis, including 1 H, 1 H‐COSY, HSQC, HMBC, and NOESY techniques.