Studies On The Chemical Constituents Of Phyllanthus Flexuosus

Phyllanthus flexuosus(sieb.et Zucc)Muell.Arg,belongs to the genus phyllanthus L(Euphorbiaceae),which is widely distributed in tropical and subtropical regions.The genus phyllanthus composed of approximately 550 to 750 species which is subdivided into 10 to 11 subgenera.And there are 35 species and 4 variants grown in China.P.flexuosus is distributed mainly in the southern areas of the Yangtze River,China.And this specie of P.flexuosus has been commonly used in our folk medicine for treatment of infectious diseases and allergic dermatitis.In this topic,the dried roots of P.flexuosus(Sieb.et Zucc.)Muell.Arg as raw material,by the repeated combination of chromatographical methods using silica gel,ODS,MCI,Sephadex LH-20,D101 porous resin and prep-HPLC,nine compounds were obtained and elucidated by means of IR,UV,HRESIMS,~1H NMR,13 C NMR,HSQC,HMBC and crystal X-ray diffraction techniques.They were identified as 1-methyl-3-(3-methylbut-2-en-1-yl)isoguanine(1),spruceanol(2),cleistanthol(3),phyllanflexoid A(4),friedelin(5),stigmasterol(6),stigmastane-3b-5,6a-triol(7),b-sitosterol-3-O-b-D-glucopyranoside(8)and palmitic acid(9).Of those,compound 1 was a new compound and the compound 2 was the first time isolated from the P.flexuosus.All compounds were evaluated for cytotoxicity against human cancer cell A549,Hela,HepG2 and SMMC-7721 in vitro by CCK-8 assays.The results showed that compounds 2,3 and 4 had good antitumor activity.In order to separate the neutral aromatic diterpenes of cleistanthol from the P.flexuosus,a kind of material by grafting choline chloride-based deep eutectic solvent(DES)onto anion exchange resin(DES-AER)were prepared.The results demonstrated that DES-AER not only offered higher adsorption capacity for cleistanthol but also exhibited better extraction efficiency of cleistanthol than those of conventional anion exchange resin(AER)and commercial C18 column,with recoveries of the materials tested at 72.14,68.21,and 82.11%,respectively.