Studies on the chemical constituents of the leaves and twigs Keteleeria davidiana Beissner var.formosana Hayata

Keteleeria davidiana var. formosana Hayata, an endemic plant of Taiwan, is also known as Cow-tail or David Keteleeria. These natural plants are only found in North part of Taiwan around Pinling township, and Mt. Tawum in the Southern Taiwan. They abruptly distributed in North and South end of Taiwan, growing along the crest line from 400-700m on the mountainside. Moreover, they are one of the rare plants which the Government proclaimed for protection.
The methanol extract from the leaves and twigs of Keteleeria davidiana var. formosana Hayata was concentrated to give a residue which was suspended into water and then partitioned with ethyl acetate. The ethyl acetate layer was separated by column chromatography on silica gel, preparative thin layer chromatography and high performance liquid chromatography (HPLC) to give forty-three compounds. Among them, seven are new compounds. The total isolates included two apocarotenoids, seven aromatics, seventeen diterpenoids, one flavonoid, forteen lignoids, and two others.
Of these compounds, the known compounds were compared with those reported in literatures or authentic samples. The new and first isolated from natural source compounds were elucidated by spectral analysis (including 1D and 2D NMR techniques and IR) and HR-MS spectrum.