44 ホパン系トリテルペノイドにおける側鎖の構造について

概要

論文の詳細を見る
Although 30 kinds of triterpenoids having the hopane, isohopane, 30-norhopane and 30-norisohopane skeletons have been isolated from the ferns, lichens and other plants, there remain some problem to resolve on the configuration of their side chain, i.e. the configuration at C-21 and C-22. Configuration at C-21: Adipedatol (I) is a fern triterpenoid of the 30-norhopane group having a hemiketal linkage between C-22 and C-28. The successful correlation of (I) to hydroxyhopane (V) and hydroxyisohopane (VI) has been established as shown in Chart 1. The results strongly suggest that hydroxyhopane and other triterpenoids of the hopane group, such as hydroxyhopanone, diploptene, neriifoliol, dryocrassol, dustanin and adiantone, have 21βH-configuration, and hydroxyisohopane has 21αH-configuration. Configuration at C-22: Dryocrassol (XI), isolated from Dryopteris crassirhizoma and found to be C-22 epimer of neriifoliol (X), has derived to adiantol B acetate (XV), a derivative of which is going to be subjected to X-ray analysis. Isoadiantol B (XVII), a constituent of Adiantum monochlamys, can be represented to have 22S-configuration according to an analogy to 20-hydroxypregnanes.
天然有機化合物討論会の論文
1968-09-20