Fern constituents: Adiantum cuneatum .2. Six new triterpenoids, neohop-18-en-12 alpha-ol, 13-epineohop-18-en-12 alpha-ol, neohop-13(18)-en-19 alpha-ol, fern-7-en-25-ol, fern-9(11)-en-25-ol, and adian-5-en-25-ol

Six new triterpenoids, neohop-18-en-12 alpha-ol (1), 13-epineohop-18-en-12 alpha-ol (2), neohop-13(18)-en-19 alpha-ol (3), fern-7-en-25-ol (4), fern-9(11)-en-25-ol (5) and adian-5-en-25-ol (6) were isolated from the fresh leaves of Adiantum cuneatum, and their structures were elucidated by means of spectroscopic analysis.