Three New Peroxy Triterpene Lactones from Pseudolarix kaempferi

Three new 3(4),9(10)-disecocycloartane peroxy triterpene lactones, named as pseudolarolides Q2, T1, and T2 (1–3, resp.), along with five known triterpenoids, were isolated from the seeds of Pseudolarix kaempferiGord. Their structures were elucidated to be (9R,10R,16R,23R,25R)-16,23-epoxy-9,10-epidioxy-3,4:9,10-disecocycloart-1(2)-ene-3,4:26,23-diolide (1), (1R,9R,10S,16R,23S,25R)-1,4:16,23-diepoxy-9,10-epidioxy-3,4;9,10-disecocycloartan-26(23)-olid-3-oic acid methyl ester (2), and (1R,9R,10S,16R,23R,25R)-1,4:16,23-diepoxy-9,10-epidioxy-3,4;9,10-disecocycloartan-26(23)-olid-3-oic acid methyl ester (3) on the basis of spectroscopic analysis.