Studies On Chemical Constituents And Antitumor Activities Of Clinacanthus Nutans

The Clinacanthus nutans belongs to Clinacanthus genus of Acanthaceae.Also known as Sabah snake grass,nodding clinacanthus,Soft nettles,Torsional order flowers and so on.It is a small shrub and can be found in tropical Asia,especially Thailand,Indonesia,Malaysia.There are two species in the Clinacanthus genus all over the world,and only one of them was found in China.It is rich in China,mainly distributed in tropical rain forest of Hainan,Guangdong,Guangxi and Yunnan province.The plant is rich in resources in Hainan province nowadays,course the planting ability on a manufacturing scale has been formed in the city of Wuzhishan.But only a little of reports about chemical constituents and pharmacological activities of C.nutans till now,although it has been used as a folk medicine for the treatment of jaundice,hepatitis ascites,swelling and pain,fracture and rheumatism palsy and so on.Under the guidance of the previous research we did,we found the extracts of C.nutans exhibited significant antitumor activities.In order to make sure the material basis of it's antitumor activities,we studied on chemical constituents and antitumor activities of C.Nutans.And it also will provide a theoretical basis for the development and utilization of C.Nutans.The acrial part of C.nutans were extracted at room temperature with 85% EtOH for three times,and each time for seven days.The residue was successively partitioned with petroleum ether and ethyl acetate.Then the fractions were purified by silica gel column chromatography,ODS,Sephadex LH-20 gel column chromatographie,and preparative HPLC.Their structures were identified by physicochemical properties,spectroscopic analysis,as well as comparisons with literature.As a result,thirty-three compounds(1-33)were isolated from85% ethanol extracts of C.nutans,including one new compound.They were divided into five types of structure,including 5 furofuran lignans,7 terpenoids,8 alkaloids,12 phenolic acid and fatty acid compounds and 1 C-glycosyl flavone.They were identified as9?-hydroxy-6-methoxy-sesamin(1),epiyangambin(2),syringaresinol(3),seartemin(4),sesangolin(5),stigmasterol(6),lupeol(7),?-sitostenone(8),?-sitosterol(9),?-sitosterol palmitate(10),(9E,11Z)-14-hydroxyotadecan-9,11-dienoic acid(11),13-hydroxy-(9Z,11 E,15E)-octadecatrienoic acid(12),2,3-hydroxypropyl-(9Z,12Z)-octadecadie noate(13),dibutyl phthalate(14),dipentyl phthalate(15),1',26'-bis-[(S)-2,3-dihydroxypropyl]-hexacosanedioate(16),(3E,6R,7E)-3-hydroxy-4,7-megastigmadien-9-one(17),4,5-dihydroblumenol A(18),isochavicinic acid(19),(E)-3-(4'-hydroxyphenyl)-acrylic acid ethyl ester(20),1-(3',4'-dimethoxyphenyl)-1-propanal(21),Ethyl 4-hydroxy-3-meth-oxybenzoate(22),4-hydroxy-3,5-dimethoxybenzaldehyde(23),pyrocatechol(24),indazole(25),aurantiamide(26),aurantiamide acetate(27),piperine(28),1-[1-oxo-7-(3,4-methylenedioxyphenyl)-2E,4E,6E-heptatneyl]-piperidine(29),1-[1-oxo-5-(3,4-methylenedioxyphenyl)-2E-heptatneyl]-piperidine(30),1-[(E)-7(3,4-methylenedioxyphenyl)-6-heptenoyl]-pyrrolidine(31),nigramide B(32),5,7-dihydroxy-8,2-dimethoxy-flavone-7-O-?-D-glucopyranoside(33).All the compounds except 6,7,9 were isolated from C.nutans and C.genus for the first time.The antitumor activity of some compouds against three human cancer lines(Hela,MCF-7 and A549)were evaluated by MTT method.Compounds 1,9,14,17,21,26,28 and29 exhibited weak cytotoxic activity against Hela,MCF-7 and A549,with IC50 values between 21.8~36.3 ?g/ml.Compounds 8 and 29 exhibited weak cytotoxic activity against Hela and MCF-7,with IC50 values between 30.4~37.7 ?g/ml.Compounds 32 exhibited selective cytotoxic activity against Hela,with a IC50 value 31.6 ?g/ml.