Cyclokirilodiol and Isocyclokirilodiol: Two Novel Cycloartanes from the Seeds of Trichosanthes kirilowii MAXIM.

Two novel cycloartane-type triterpene alcohols possessing a monohydroxy-tetrahydrofuran ring in the side chain, cyclokirilodiol and isocyclokirilodiol, were isolated from the nonsaponifiable lipid fraction obtained from the methanolic extract of Trichosanthes kirilowii seeds. Their structures were determined as (22S, 24S)-22, 25-epoxy-24-hydroxy-5α-cycloartan-3β-ol and (22R, 24S)-22, 25-epoxy-24-hydroxy-5α-cycloartan-3β-ol, respectively, by detailed spectroscopic analyses.