Methoxylation Of The Stilbenes Originated From Leaves Of Cajanus Cajan And Their Anti-tumor Activities In Vitro And Studies On The Chemical Constituents Of Marsdenia Lachnostoma Benth

Part one Methoxylation of the Stilbenes Originated from Leaves of Cajanus cajan and their Anti-tumor Activities in VitroObjectiveAccording to literatures,a large number of stilbenes such as longistylin C in Cajanus Cajan exhibited singificant anti-tumor activity,and many active compounds from Chinese herbal medicine have also been reported having an inhibitory effect on cytochrome P450.After the natural active ingredients are structurally modified,the inhibitory effect on cytochrome P450 is significantly enhanced.Therefore,structural modification and structural identification on four stilbenes in Cajanus Cajan as well as on the inhibition of cytochrome P450 and the anti-tumor activity in vitro in order to obtain new cytochrome P450 inhibitors and Anti-tumor compounds.Methods1.The products were purified through silica gel column chromatography and their chemical structures were identified by ¹H NMR,¹³C NMR,MS,¹H-¹H COSY,¹³C-¹H COSY,HMBC and IR spectroscopic analysis.2.Through CCK-8 assay,tested the compounds effect on human breast cancer（MDA-MB-231）,cervical cancer（HeLa）,liver cancer（HepG2）,colon cancer（SW480）,and non-small cell lung cancer（A549,NCI-H460 and NCI-H1299）.3.Tested the compounds’inhibitory effect on cytochrome P1B1.Results1.The products were purified through silica gel column chromatography and their chemical structures were identified by spectroscopic analysis as2-isoprenyl-3,5-dimethoxy-stilbene（1）,O-methyl-cajanonic acid A（2）、5-O-methyl cajanotone（3）and 3-O-methyl cajaninstilbene acid（4）,respectively.Among them 3 was a new compound.2.The results showed that 1)longistilin C distinctly inhibited the proliferation of all the seven cell lines tested with the half inhibitory concentrations（IC50）to MDA-MB-231,HeLa,HepG2,and SW480 at 14.4、16.1、19.6、17.4μM,suppressed moderately to A549,NCI-H460 and NCI-H1299 cells with IC50 values as 25.7–29.6μM;2)cajaninstilbene acid gave a weak inhibitory effect to HepG2,A549,NCI-H460,NCI-H1299 and MDA-MB-231 cells with IC50 as 44.9–78.3μM;3)tri-O-methylated resveratrol showed significantly cytotoxity against MDA-MB-231,HeLa,SW480 and HepG2 cells with values of IC50 in the range of 16.1-17.4μM;4)O-methylated stilbenes 1-4did not exhibited obvious cytotoxicity in the cell lines used.3.The cytochrome P450 assay showed that 3-O-methyl cajanonic acid A exhibited a 6 times inhibited effect on CYP1B1 of CAA with IC₅₀0 as 5.4μM,and the half inhibitory concentration of cajaninstilbene acid and 3-O-methyl cajaninstilbene acid was all lower than 5μM.Conclusion1.Longistylin C exhibited a similar anti-tumor activity to that of resveratrol in vitro,but its methyl etherification product did not show obvious activity,indicating that the methyl etherification had no significant effect on enhancing the antitumor activity of stilbene in vitro;2.Methyl etherification enhanced the inhibitory effect of CAA on CYP1B1.Part two Studies on Chemical Constituents of Marsdenia lachnostoma BenthObjective In this thesis,phytochemical investigation on Marsdenia lachnostoma Benth led to the isolation of 6 compounds.The struture of these compounds were elucidates by extensive spectroscopic analyses.Lastly,compared to the literature to identified the structure of compounds.Methods The compounds were separated from the ethyl acetate fraction of Marsdenia lachnostoma Benth by silica gel column chromatography,Sephadex LH-20 Sephadex LH-20,ODS,preparative HPLC.Then Spectroscopic methods（UV,IR,1D and 2D NMR,mass spectrometry,etc.）were used to analyze the structure of the compound and compare it with the literatures to determine the structure of the compound.Results The compounds from Marsdenia lachnostoma Benth included: hexadecan-1-ol（1）,lupeol（2）,stigmast-1,5-dien-3-ol（3）,betulin（4）,benzoic acid（5）,conduritol A（6）.Conclusion Phytochemical investigation on Marsdenia lachnostoma Benth,6 compounds were identifided as: hexadecan-1-ol（1）,lupeol（2）,stigmast-1,5-dien-3-ol（3）,betulin（4）,benzoic acid（5）,conduritol A（6）,isorhamnetin-3-O-robinobioside（7）.All of them were isolated from Marsdenia lachnostoma Benth for the first time.