Studies On The Chemical Constituents And Bioactivities Of Justicia Procumbens L.

Justicia procumbens L.(Acanthaceae)is an annual herb and mainly distributed in South of China.The whole plant of J.procumbens has multiple clinical efficacy such as decrease internal heat,detoxification and so on.It has a long history of being used to treat colds,fevers,throat infections and other diseases.A number of arylnaphthalide lignans have previously been reported as the main components of this plant and have cytotoxic and antiviral activities.The cytotoxic activity in vitro of various Chinese herbal medicines were screened in our preliminary experiment,and results showed that the ethanol extract of J.procumbens had significant activity of inhibiting the growth of tumor cells in vitro.In this study,the chemical constituents of J.procumbens were studied and some of the compounds were screened for cytotoxic activity in vitro.The structural-activity relationship was also discussed.By means of many different chromatographic methods such as silica gel CC,Sephadex LH-20 and HPLC,22 compounds were isolated from the 60%ethanol extract of the plant of J.procumbens.Then chemical and spectral evidence(IR,NMR,MS)were used to elucidate the structure of these compounds.They were identified as: Justicidin A(1),6?-hydroxy justicidin B(2),Justicidin B(3),5 ?-methoxy retrochinensin(4),Diphyllin(5),Justicidin D(6),Procumbenoside C(7),Tuberculatin(8),Justicianene A(9),Justicianene D(10),?-daucosterin(11),stigmasterol(12),?-sitosterol(13),quercetin(14),acacetin-7-O-?-D-lutinoside(15),(2S)1-O-tetradecanoyl-3-O-(6-sulfo-?-D-qui novopyranosyl)glycerol(16),Sarcoglycoside A(17),4-hydroxybenzoic acid(18),vanillic acid(19),vanillin(20),Choline sulfate(21),palmitic acid(22).These compounds were classified into 8 lignins,2 cyclopeptide alkaloids,3 steroids,2 flavonoids and 7 other structural compounds.Compounds 16,17,21 and 22 were isolated from plants for the first time.In this study,some compounds were tested for their cytotoxic activity in vitro.Compounds 1,2,3,5 and 22 showed significant cytotoxic activities against HeLa,MCF-7,A549 and H460 cells in vitro.The IC50 s of compound 5 against these four cells were 3.47?g/mL,8.79?g/mL,21.92?g/mL and 16.10?g/mL,respectively.The cytotoxic activity of compounds 1,2,3,and 5 against HeLa cells was significantly better than the positive drug cisplatin..