Fern constituents: triterpenoids from Adiantum capillus-veneris.

Two new migrated hopane triterpenoids, viz. 4alpha-hydroxyfilican-3-one and fern-9(11)-en-12beta-ol, and olean-18-en-3-one and olean-12-en-3-one as the first example of oleanane compounds from Adiantum ferns were isolated along with many other known triterpenoids from Adiantum capillus-veneris of China and Egypt. Their structures were elucidated by spectroscopic analyses.