Study On The Chemical Constituents And Activity Of The Root Of Wrightia Pubescens R.Br.

Wrightia pubescens R.Br.?Apocynaceae?,known as“Daodiaobi”in China,is a commonly used traditional herbal medicine embodied in National Herbal Medicine Assembly?Third Edition?.It's roots and leaves can be used as medicine.The root can be used to treat cervical lymph node tuberculosis,rheumatoid arthritis,and chronic bronchi.The whole plant of Wrightia pubescens R.Br.mainly distributed in Guangdong,Guangxi,Guizhou and Yunnan provinces has long been used to treat cold,fever,cough,pain,inflammation of the throat and indigestion,etc.Modern pharmacological studies have shown that they have obvious cytotoxic and anti-inflammatory effects.Preliminary tests on 10 Chinese herbs for anti-tumor activity in vitro showed that the ethanol extract,CHCl₃ extract of Wrightia pubescens R.Br.possessed obvious activity in inhibiting tumor cell growth.Based on the review on the chemical constituents and bioactivities research of the Wrightia R.Br.,chemical constituents of Wrightia pubescens R.Br.were studied systematically and deeply,their anti-tumor activities were tested to obtain compounds with novel structures or significant bioactivities.In our investigation,by means of many different chromatographic methods such as silica gel CC,reversed phase C₁₈,Sephadex LH-20,MPCC,preparative HPLC etc,29 compounds isolated from the 75%ethanol extract of the herbs of Wrightia pubescens R.Br.were elucidated on the basis of chemical and spectral evidence?IR,NMR,MS?.They were identifie as:4-hydroxybenzoicacid?1?,Vanillicacid?2?,Vanillin?3?,4-hydroxymethyl-5-hydroxy-2H-pyran-2-one?4?,Scopoletin?5?,Coumarin?6?,Cleomiscosin B?7?,Mollugin?8?,Quercetin?9?,Genistein?10?,Linarin?11?,medioresinol?12?,Allantoin?13?,Uracil?14?,4-?hydroxymethyl?-5hydroxy-2H-pyran-2-one?15?,Tryptanthrin?16?,N-?2?-Hydroxyeicoxyicosanoyl?-1,3,4-trihydroxy-2-aminoheptadec-5-ene?17?,octacosanol?18?,?-sitosterol?19?,?-daucosterol?20?,3?-hydroxysitost-5-en-7-one?20?,5,6?-epoxy-5?-stigmastan-3?-ol?21?,5,6?-epoxy-5?-stigmastan-3?-ol?22?,betulinic acid?23?,Betulonic acid?24?,Ursonic acid?26?,Oleanolic acid?27?,3?-acetoxy-urs-l2-ene-ll-one?28?,3?,23-dihydroxyolen-12-en-28-oic acid?29?.The 22 of the compounds them were first isolated from Wrightia R.Br.,they were compounds 1-5,8,12,13-22,25,26,27,28 and 29.The compounds obtained from Wrightia pubescens R.Br.referred to3 aromatic nucleus derivational,3 flavones,3 coumarins,5 steroids,6triterpenes,5 nitrogen compounds and 4 other structural types.Compounds were selected for their anti-tumor activities against HeLa,MCF-7,HepG2and HCT116 cells.Compound 16 showed cytotoxic activity against HeLa,MCF-7,HepG2 and HCT116 cells in vitro with IC₅₀ of 3.7,4.5,6.9,2.3?m/mL.The IC₅₀ of compound 27 against HeLa,MCF-7,HepG2 and HCT116 cells was 3.9,4.2,6.3 and 5.6?m/mL,respectively.The hepatoprotective effects of compounds 7,8,12 were determined through MTT colorimetric assay in L02 cells.Bicyclol was used as a positive control drug,and the compounds 7,8,12 showed obvious hepatoprotective activities,especially the hepatoprotection activities of compound 12 was significantly higher than that of the positive control drug Bicyclol.