Chemical Constituents from Aerial Parts of Dendrobium hercoglossum (Orchidaceae) and Their Biological Activities

Abstract:

In order to understand the chemical constituents of Dendrobium hercoglossum, fourteen compounds were isolated from the aerial parts of D. hercoglossum by using various column chromatography with silica gel, sephadex LH-20, and semi-preparative HPLC. Based on spectroscopic data, their structures were identified as 3,4,5-trimethoxyphenol (1), 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-propan-1-one (2), methyl 3-(p-hydro- xyphenyl) propionate (3), justiciresinol (4), ficusal (5), meso-secoisolariciresinol (6), threo-2,3-bis-(4-hydroxy- 3-methoxyphenyl)-3-methoxypropanol (7), (+)-pinoresinol (8), aloifol Ⅰ (9), dendrocandins T (10), 3-hydroxy- 1-(4-hydroxy-3-methoxyphenyl)-propan-1-one (11), 1,3,5-trimethoxybenzene (12), homovanillyl alcohol (13) and (−)-syringaresinol (14). Compounds 1−12, 14 were obtained from D. hercoglossum for the first time, and compounds 7, 10, and 14 were isolated from Dendrobium species for the first time. The compounds 4, 8 and 10 showed significant inhibitory activity, with IC₅₀ of (10.40±0.36), (12.16±0.18) and (9.46±0.78) μmol/L, respectively.

Key words:Orchidacae;Dendrobium hercoglossum;Chemical constituent;Tyrosinase