From the methanol extract of dried powders of Hedyotis diffusa Willd. (Rubiaceae) plant growing in Tuyen Quang Province, three compounds were isolated and identified: B-sitosterol, daucosterol and ursolic acid. Their structures were confirmed by various spectral methods (IR, NMR, MS, 1H-NMR, 13C-NMR, etc.) and by comparison with those of references. | JOURNAL OF SCIENCE OF HNUE Natural Sci. 2010 Vol. 55 No. 6 pp. 57-61 ISOLATION AND STRUCTURAL DETERMINATION OF SOME CHEMICAL CONSTITUENTS FROM Hedyotis diffusa Willd. RUBIACEAE GROWING IN TUYEN QUANG PROVINCE Pham Huu Dien and Tuong Hong Nhung Hanoi National University of Education E-mail dienhp@ Abstract. From the methanol extract of dried powders of Hedyotis diffusa Willd. Rubiaceae plant growing in Tuyen Quang Province three com- pounds were isolated and identified β-sitosterol 1 daucosterol 2 and ursolic acid 3 . Their structures were confirmed by various spectral meth- ods IR NMR MS 1 H-NMR 13 C-NMR etc. and by comparison with those of references. Keywords Hedyotis diffusa Willd. β-sitosterol daucosterol ursolic acid isolation. 1. Introduction Bach Hoa Xa Thiet Thao is the Vietnamese name of the Hedyotis diffusa Willd. Rubicaceae plant which belongs to the family of Rubiaceae and is one of the most popular traditional Vietnamese medicines 1 . Extensive pharmacological investigations performed so far on Hedyotis diffusa have shown that this herbal medicine has several biological activities such as human neutrophil elastase inhibitor 2 neuroprotection 3 antitumor activity 4 . Hedyotis diffusa contains a majority of anthraquinone 5 irridoid glucoside flavonoids 2 3 glucans 6 . In this paper we report our investigation on the chemical constituents of Hedyotis diffusa growing in Tuyen Quang Province. 2. Content . Experiments General experimental procedures IR spectra were recorded on SHIMADZU-FTIR 8101M spectrophotometer using KBr disks. NMR spectra 1 H-NMR 13 C-NMR DEPT HSQC HMBC were recorded on Brucker Advance 500MHz. The chemical shift values δ are given in ppm with TMS as internal standard coupling constant J by Hz . EIMS LC- MSD spectra were recorded on HP 5989B Agilent mass spectrometer. Silica gel 57 Pham Huu Dien and Tuong Hong Nhung Merck Co. Germany was used for flash chromatography. TLC was carried out on precoated Si gel GF254 Merck Co. .
