抄録
Fifteen compounds (Table I) were isolated from the xylem of root of Xanthoxylum arnottianum MAXIM. (Japanese name "Iwa-zansho"). Base I (9), mp 210°, was assumed to be des-N-methylchelerythrine. Four were known coumarins ; marmesin (19), suberosin (8), osthenol (21), and 7-demethylsuberosin (23). Two new coumarins were confirmed to be rutaretin methyl ether (25), which was already known as a methylated product of a natural phenolic coumarin, rutaretin (24), and (R)-(-)-columbianetin (28), the antipode of the known (S)-(+)-columbianetin. Isolation of both products from a natural source is for the first time. Three other new coumarins, arnottinin (26), C_<14>H_<14>O_4,mp 191-193°; arnottianol (12), C_<15>H_<16>O_4,mp 119-121°; and xanthoarnol (27), C_<14>H_<14>O_5,mp 208-209°, were characterized. Two lignans, l-asarinin (7) and syringaresinol (31), β-sitosterol (2), and palmitic acid (1) were recognized. A new sesquiterpene, sesquiterpene-I (4), C_<15>H_<26>O, mp 80°, was assumed to have a cadinane or a guaiane skeleton from its nuclear magnetic resonance spectral data.
