[Chemical Constituents of Ethyl Acetate Extract from Viola biflora].

Objective: To isolate the chemical constituents of ethyl acetate extract from Viola biflora. Methods: Isolation and purification were carried out on repeated silica gel column chromatography,PTLC,and Sephadex LH-20. The structures of these compounds were elucidated by physico-chemical properties and spectral analyses. Results: Twelve compounds were isolated from Viola biflora,which identified as aurantiamide acetate( 1),solalyratin B( 2),esculetin( 3),scopoletin( 4),lupeol( 5),132S-hydroxypheophytin a( 6),vomifoliol( 7),dibutyl phthalate( 8),(-)-dihydrovomifoliol( 9),grasshopper ketone( 10),crassifol( 11) and ß-sitosterol( 12). Conclusion: All the compounds are isolated from Viola biflora for the first time. Compounds 2,7,9 ~ 11 are isolated from Viola genus for the first time.

Anti-complementary constituents of Viola kunawarensis.

Activity-guided fractionation for complement inhibitors led to the isolation of 22 known compounds from Viola kunawarensis. Chemical types include six sterol compounds, three coumarin compounds, five megastigmane compounds, two triterpenoid compounds, two phenylpropanoid compounds, one chlorophyll, one amide, and two lipid compounds. Among which, two sterols (stigmasta-4-ene-3ß,6ß-diol and saringosterone), one amide (aurantiamide acetate) and a norsesquiterpenoid (solalyratin B) exhibited better anti-complementary effects with CH50 values ranging from 0.02 to 0.08 mM, which are plausible candidates for developing potent anti-complementary agents.