Studies On Chemical Constituents Guided By Brine Shrimp Lethality Assay From Derris Trifoliata (Lour.)

Objective:To stuty the secondary metabolites of Derris trifoliata Lour. from Sanya in Hainan, China. New and bioactive natural compounds were found and acquired from this plant, tested the brine shrimp lethal activity of the extraction. Accordingly better theoretical basis were available to development and use of plant resources in China.Methods:①Three times ambient temperature extraction were used with50%ethanol solution, and the extraction was was subjected to column chromatography on silica gel, sephadex LH-20and HPLC.②Structure of the compounds were established using UV, MS,1D and2D NMR (HSQC, HMBC, COSY and NOESY) spectroscopic techniques.③The biological activity of the extraction was tested by the brine shrimp lethal activity.Result:Thirty compounds were isolated from the ethyl acetate extract of the stem bark of D. trifoliata Lour, and twenty two compounds were determined, which included fourteen flavonoids [4’,5,7-trihydroxy-6,8-di-(2-hydroxy-3-methylbut-3-enyl)-flavanone (1),4’,5,7-trihydroxy-6,8-di-(trans-2-hydroxy-3-methylbut-3-enyl)-flavan-one(2),4’,5,7-trihydroxy-6,8-di-(cis-2-hydroxy-3-methylbut-3-enyl)- -flavanone (3), rotenone(4),12a-hydroxyrotenone (5), deguelin (6), tephrosin (7),6a,12a-dehydrorotenone (8), dehydrodeguelin (9),7a-O-Methyldeguelol (10),7a-O-Methylelliptonon (11), daidzein (12),5,7,3’,4’-tetrahydroxy-6,8-diprenylisoflavone (13),4’-Hydroxy-7-methoxy-flavanone (14)]; four lingnans [micromelosides P (15), micromelosides Q (16), cis-micromelosides Q (17), trans-micromelosides Q (18)]; four glucosidases [9-hydroxymegastigma-4,7-dien-3-one-9-O-b-D-glucoside (19),2-benzyloxy-6-(hydroxymethyl) tetrahydropyran-3,4,5-triol (20), phenethyl-8-O-β-D-glueopyranoside (21), cinnamyl (3-d-glucopyranoside (22)].Conclusion:Among them, compounds1、2、3、17and18were new ones, and compounds13、15、16、19、20、21�'�22were found from the genus Derris for the first time. The results of bioassay showed that compounds4-10have strong brine shrimp lethal activity, whose LD50were lower than10μg/mL; and the new compound1showed weak toxicity (LD50=211.31μg/mL).