One new anthraquinone glycoside. 6-O-(alpha-L-rhamnopyranosyl (1 -> 6)-beta-D-glucopyranosyl)emodin (1). and two new sesquilignans. seslignanoccidentaliols A (2) and B (3), were isolated from the whole plant of Cassia occidentalis. The structures of the new compounds were established by means of spectroscopic methods, especially 2D-NMR data ((1)H.(1)H-COSY. HMQC, HMBC. and ROESY). as well as HR-ESI-MS analysis. One previously reported sesquilignan. crythro-guaiacylglycerol-beta-O-4'-(5')-methoxylariciresinol, was revised to be seslignanoccidentaliol A (2). The 6-O-(alpha-L-rhamnopyranosyl(1 -> 6)-beta-D-glucopyranosyl)emodin (1) exhibited moderate anti HIV-1 activity with an EC(50) value of 2.90 mu g/ml and a therapeutic-index (TI) value of 260.
1.Chinese Acad Sci, State Key Lab Phytochem & Plant Resources W China, Kunming Inst Botany, Kunming 650204, Peoples R China 2.Chinese Acad Sci, Grad Sch, Beijing 100049, Peoples R China 3.Chinese Acad Sci, Lab Mol Immunopharmacol, Kunming Inst Zool, Kunming 650223, Peoples R China 4.Kunming Med Coll, Yunnan Pharmacol Labs Nat Prod, Kunming 650031, Peoples R China