Phytochemical study on American plants I. Two new phenol glucosides,together with known biflavones and diterpene,from leaves of Juniperus occidentalis Hook

Two new phenol glucosides termed juniperosides I (1) and II (2) were isolated, together with known two biflavones, cupressuflavone and amentoflavone and a diterpene, 3beta-hydroxy sandaracopimaric acid, from leaves of Juniperus occidentalis HOOK. (Cupressaceae) collected in Oregon, U.S.A., and their structures were established as (1S)- and (1R)-1-(2'-hydroxy-6'-methylphenyl)ethanol 2'-O-beta-D-glucopyranosides (1, 2), respectively, on the basis of spectral, chemical, and synthetic evidence. The glycosides 1 and 2, as well as the corresponding aglycones 1a and 2a, are apparently novel types of naturally occurring compounds; to our knowledge, isolation of these types of natural phenol derivatives has only rarely been reported from the vegetable kingdom.