Triterpenoids from callus tissue cultures of Paeonia species

Six triterpenoids were isolated from the callus tissues of Paeonia japonica, P. lactiflora and P. suffruticosa. Four of the compounds are new from a natural source: 11α,12α-epoxy-3β,23-dihydroxyolean-28,13β-olide, 3β-hydroxy-11-oxo-olean-12-en-28-oic acid, 3β-hydroxy-oleana-11,13(18)-dien-28-oic acid and 3β,23-dihydroxy-oleana-11,13(18)-dien-28-oic acid. The postulated biosynthetic sequence of these compounds is discussed and the triterpenoids produced from the three callus tissues have been compared from a chemotaxonomical standpoint.