The chemical constituents from the leaves of Ilex guayusa were investigated. Sixteen triterpenoids were isolated from the 95% ethanol extract of dried leaves of I. guayusa by silica gel, Sephadex LH-20, and ODS column chromatographies and semi-prepa-rative HPLC. Those triterpenoids were identified by NMR, HR-MS, and literature analysis: 3β-hydroxy-11α,12α-epoxy-24-nor-urs-4(23)-ene-28,13β-olide(1), 3β-hydroxy-24-nor-4(23),12-oleanadien-28-methyl ester(2), oleanolic acid(3), 3β,28-dihydroxy-12-oleanene(4), 2α,3β-dihydroxy-11α,12α-epoxy-24-'nor-olean-4(23)-ene-28,13β-olide(5), ursolic acid(6), 3β,23-dihydroxy ursolic acid(7), 3β,28-dihydroxy-12-ursene(8), 3β-28-nor-urs-12-ene-3,17-diol(9), 3β-hydroxyurs-11-ene-28,13β-olide(10), 13β,28-epoxy-3β-hydroxy-11-ursene(11), 3β-hydroxy-28,28-dimethoxy-12-ursene(12), 3β-hydroxy-24-nor-urs-4(23),12-dien-28-oic acid(13), 3β-hydroxy-24-nor-urs-4(23),12-dien-28-methyl ester(14), 2α,3β-dihydroxy-11α,12α-epoxy-24-nor-urs-4(23)-ene-28,13β-olide(15) and 2α,3β-dihydroxy-11α,12α-epoxy-24-nor-urs-4(23),20(30)-dien-28,13β-olide(16). Compounds 1-2 were new compounds, and compounds 4-5, 7 and 9-16 were isolated from I. guayusa for the first time.
Keywords: Aquifoliaceae; Ilex guayusa; chemical constituents; triterpenoids.