Studies On Chemical Composition And Bioactivity In Two Species Of The Siegesbeckia

Herb a Siegesbeckiae(compositae)is a traditional Chinese herbal medicine.Three species of Siegesbeckia grow in China(Siegesbeckia orientalis L.?Siegesbeckia pubescens M.and Siegesbeckia glabrescens M.)and their aerial parts have been used as the traditional Chinese medicine Xi-Xian to prevent inflammation and relieve pain,protect cardiovascular system and improve microcirculation.It is one of the most potential traditional Chinese medicineIn order to excavate the active components of traditional medicinal plants and develop and utilize the medicinal resources better,the 95%ethanol extracts of two species of Compositae {Siegesbeckia orientalis L.and Siegesbeckia glabrescens M.)were studied systematically in this paper.The main research contents include(1)The compounds from natural sources in the Siegesbeckia were extracted and separated by a variety of separation and purification methods(thin layer chromatography,column chromatography,high performance liquid,etc.);(2)Through a variety of spectroscopic analysis,including one-dimensional(1H,13C),two-dimensional(1H-1H COSY,HSQC,HMBC)nuclear magnetic resonance technology and infrared,ultraviolet,mass spectrometry and other methods,combining the physical and chemical properties of monomer compounds With reference to related literatures,the structure of the compound was determined by analyzing the structure of the separated monomer compounds.Combined with the chemical method and the comparison of CD spectra,the absolute configuration of the new compound was determined;(3)The anti-inflammatory,antibacterial and antitumor activities of the isolated natural products were studiedIn this study,48 compounds were isolated and identified from Siegesbeckia,including 11 compounds with novel structure(compounds 1-11),all of which are gemalane sesquiterpenoids;37 compounds were known,including 17 sesquiterpenoids(compounds 12-28),20 diterpenoids(compounds 29-48).Known compounds identified as:(4?,10E)-6a,14,15-trihydroxy-8?-(isobutyryloxy)germacra-10,11(13)-diene-12-oicacid12,6-lactone(12);2-propenoicacid,2-methyl-2,3,3a,4,5,8,9,10,11,1a-decahydro-6,10-bis(hydroxylmethy l)-3-methylene-2-oxocy-clodeca[?]furan-4-ylester(13);(1(10)E,4?)-8?-(angeloyloxy)-6a,14,15-tri-hydroxygermacra-1(10),11(13)-diene-12-oicacidl2,6-lactone(14);9?-ethoxy-8?-(2-isobu tyryloxy)-14-oxo-acan-thospermolide(15);(1(10)E,4Z,6?,8?,9?)-9-ethoxy-6,15-dihydroxy-8-(2-methylacryloxy)-14-oxogermacra-1(10),4,11(13)-trieno-12,6-lactone(16);(2Z)-2-methylbut-2-enoicacid(3?S,4S,5S,6E,10Z,11?R)-5-(ethoxy)-6-formyl-2,3,3?,4,5,8,9,11?-octahydro-10-(hydroxymethyl)-3-methylene-2-oxocyclodeca[?]furan-4-ylester(17);(1(10)E,4Z)-9?,15-dihy-droxy-8?-iso-butyryloxy-14-oxo-melampolide(18);(1(10)E,4Z,6?,8?,9?)-6,9,15-trihydroxy-8-(methylacryloxy)-14-oxogermacra-1(10),4,11(13)-trieno-12,6-lactone(19);lecocarpinolideF(20);sigesbeckialideA(21);(3?S,4S,5S,6Z,10Z,11?/R)-5-(acet-yloxy)-2,3,3?,4,5,8,9,11?-octahydro-6,10-bis(hydroxymetyl)-3-methylene-2-oxo-cyclodeca[b]furan-4-ylester(22);orientalide(23);lecocarpinolideB(24);pubetallin(25);(1(10)E,4Z)-8?-(angeloyloxy)-9?-methoxy-6?,15-dihydroxy-14-oxo-germacra-1(10),4,11(13)-trien-12-oicacid12,6-lactone(26);9?-Hydroxy-8?-methacryloyloxy-14-oxo-acanthospermolide(27);3?-hydroxybalchanolide(28);16?-H-ent-kaurane-17,18-dioic acid,17-methyester(29);ent-16?,17-dihydroxy kauran-19-oic acid(30);16?-hydro-ent-kauran-17,19-dioicacid(31);ent-14?,16-epoxy-8-pimarene-3?,15-diol(32);14?,16-epoxy-ent-3?,15?,19-trihydroxypimar-7-ene(33);14?,16-epoxy-ent-3?,15?,19-trihydroxypimar-7-ene(34);ent-16-acetoxy-8(14)-pimarene-3,15S-diol,named16-O-acetyldaru tigenol(35);ent-2-oxo-15,16,19-trihydroxypimar-8(14)-ene(36);ent-3?,15R,16-trihydroxy pimar-8(14)-ene(37);ent-kauran-16?,17,18-triol(38);(R)-1-((2S,4aR,4bS,8R,8aS)-8-(hydroxyl-methyl)-2,4b,8-trimethyl-2,3,4,4a,4b,5,6,7,8,8a,9,10-dodecahydrophenanthren-2-yl)ethane-1,2-diol(39);(S)-1-((2S,4aR,4bS,8R,8aS)-8-(hydroxymethyl)-2,4b,8-trimethyl-2,3,4,4a,4b,5,6,7,8,8a,9,10-dodecahydrophenanthren-2-yl)ethane-1,2-diol(40);darutigenol(41);15,16-di-O-acetyldarutoside(42);ent-(15R)-ace-toxypimar-8(14)-ene-3?,16-diol-3-O-?-D-glucopyranosid e(43);ent-3,15,16-trihydroxypi-mar-8(14)-en-3-O-?-glucopyranoside-15,16-acetonide(44);ent-2?,15R,16,19-tetrahydroxypimar-8(14)-ene(45);ent-3?,15R,16-trihydroxypimar-8(14)-en-3?-O-?-D-glucopyranoside(46);kirenol(47);ent-3?,15S,16-trihydroxypimar-8(14)-en-3?-O-?-D-glucopyranoside(48).A series of isolated sesquiterpenes were screened for anti-tumor activity,and their structure-activity relationships were studied.It is found that a group of compounds containing methacryloyl group in C-8 are more active than other analogues.A total of 11 compounds,including 7 fatty acid compounds(49-55)and four other small-molecule compounds(56-59),were isolated and identified from the ethyl acetate extraction phase of Siegesbeckia glabrescens M.Known compounds identified as 15-hydroxy-10(14)-oplopen-4-one(56);clovane-2?,9?-dio(57);(3S)-3-hydroxy-?-ionone(58);3,4-trans-dihydroxy-6-methoxy-2,2-dimethyl-chroman(59).We screened the antibacterial,antitumor,and anti-inflammatory activities of these Oxylipins compounds,and the results of the study indicate that they have potential antibacterial activity against Gram-positive bacteria.