Frutoic acid, a dimeric kaurane diterpene from Xylopia frutescens

Sitosterol and six diterpenes were isolated from green fruit, stem bark and leaves of Xylopia frutescens and characterized as ent-15α-acetoxy-kaur-16-en-19-oic acid (xylopic acid), ent-kaur-16-en-19-oic acid (kaurenoic acid), ent-16β-hydroxy-kaurane, ent-kaur-16-en-19-ol, ent-16β-hydroxy-kauran-19-oic acid and ent-16β,17-dihydroxy-kauran-19-oic acid. Acutifloric acid, a diterpenic dimer, and its 7β-hydroxy-derivative, a novel compound named frutoic acid, were also isolated.