A novel onoceranoid triterpene, named lamesticumin G (1) along with four known compounds (2-5) were isolated from the ethyl acetate extract of the fruit peels of Lansium parasiticum. The structure of lamesticumin G (1) was fully characterised using spectroscopic data. Lamesticumin G (1) inhibited α-glucosidase (maltase) with IC50 value of 2.27 mM, while 2-5 showed no inhibition.
Keywords: Lamesticumin G; Lansium parasiticum; Meliaceae; diabetes; onoceranoid; triterpenoid; α-glucosidase.