Chemical Studies On The Eucommia Ulmoides Oliv.

Eucommia ulmoides Oliv., the sole species of the genus Eucommia and the family Eucommiaceae, is a native tree in China. The bark is a high-value product and commonly used in traditional Chinese. Now it is widely cultivated in Japanese and Korean. In the bark of E. ulmoides Oliv., the main chemical constituents are iridoids, lignans, and flavonoids.In Chinese traditional medicine, the bark of the plant has been used for treat lower back pain, aching knees, it also has used as tonic and anti-stress. Modern pharmacological researches show that the cortex of the plant has anti-hypertensive, suppressing on mutagenicity, prevent miscarriage, treat arteriosclerosis et al. Many reports show flavonoids, stilbenes, coumarins, lignans show phyto- estrogenic activities, but few reports about the chemical constituents in E. ulmoides Oliv. show phytoestrogenic activities. Therefore, we have conducted studies on the phytochemical investigation of Eucommia ulmoides bark.Eighteen compounds were isolated from the ethanol extracts of the bark of E. ulmoides Oliv. employing solvent extraction, silica gel, polyamide and macroporous resin column chromatography, recrystallization, along with TLC analysis. The structures of seventeen compounds were identified on the basis of spectral methods including NMR, MS and comparing with authentic samples. They are sitosterol (EUP-1), betulinic acid (EUP-3), genipin (EUE-1), caffeic acid (EUE-2), (αR)-α-O-β-D-glucopyranosyl-4,2′,4′-trihydroxydihydrochalcone (EUE-3), dauco- sterol (EUE-4), geniposide (EUE-5), 4,2′,4′-trihydroxychalcone (EUE-6), (αR)-α,4,2′,4′-tetrahydroxydihydrochalcone (EUE-7), quercetin (EUE-8), pinoresinol- 4′-O-β-D-glucopyranoside (EUB50-1), eucophenoside (EUB50-2), syringaresinol- 4′-O-β-D-glucopyranoside (EUB50-3), wogonside (EUB50-5), sucrose (EUW30-1) and D-glucose (EUW30-2).Among these compounds, EUB50-2 is a new phenolic glucoside. This is the first report of EUE-3, EUE-6, EUE-7, EUB50-5 from the title plant, and EUP-3, EUE-1, EUE-3, EUB50-1, EUB50-3 show phytoestrogenic activities.