Abstract: Three phenolic compounds were isolated from the aerial parts of Caragana leucophloea Pojark.(Leguminosae).They were identified as liriodendrin (1),vanillic acid (2) and chlorogenic acid (3) by physicochemical properties and spectrometric methods.Compounds 1 and 2 exhibited strong antibacterial activity with the median inhibitory concentration (IC₅₀) values from 8.11 to 22.88 μg/mL.Both 2 and 3 demonstrated inhibitory activity on the spore germination of Magnaporthe oryzae with IC₅₀ values of 105.04 and 32.26 μg/mL and on the mycelial growth of Fusarium oxysporum f.sp.niveum with IC₅₀ values of 108.45 and 45.26 μg/mL, respectively. 2 and 3 also exhibited antinematodal activity on Caenorhabditis elegans. When the incubation time was 48 h,the IC₅₀ values were 46.57 and 55.17 μg/mL,respectively.Additionally,2 showed hydroxyl radical scavenging activity with IC₅₀ of 67.96 μg/mL and had inhibitory activity on ferrozine Fe²⁺ complex formation with IC₅₀ value of 93.59 μg/mL.These phenolic compounds were isolated from C.leucophloea for the first time.

Key words: Leguminosae, Caragana leucophloea, liriodendrin, vanillic acid, chlorogenic acid, biological activities