Studies On Chemical Constituents And Biological Activity Of Casearia Kurzii

Casearia kurzii was chemically investigated and the anti-cancer and anti-oxidative activities of the compounds were also tested in this paper.Some diterpenoids of the clerodane-type exhibited significant anti-proliferative activity against the A549 cancer cells,while those of the dolabellane-type showed remarkable quinone reductase inducing activity.The twigs and leaves of Casearia kurzii were extracted with ethanol(95%,v/v)at room temperature,and a total of 57 compounds including 17 new and 40 known ones were isolated by column chromatography of silica gel,C18 reverse-phased silica gel,and Sephadex LH-20 as well as semi-preparative HPLC.The structures were established on the basis of NMR,MS,UV,and IR spectroscopic techniques in combination with single-crystal X-ray crystallographic analysis.The new compounds obtained in this study include a pair of racemic 15-nordolabellane-type diterpenoids,(±)-caseadolabellol A(+1 and-1),three new dolabellane-type diterpenoids,caseadolabellols B-D(2-4),two new dolastane-type diterpenoids,caseadolastols A and B(5 and 6),as well as ten new clerodane-type diterpenes,caseaclerodols A-J(7-16).The single-crystal X-ray crystallographic analysis revealed a racemic mixture of 1,which was separated into a pair of enantiomers,(+)-1 and(-)-1 by HPLC on a chiral column and the absolute configurations of them were assigned by analysis of the CD spectra.The 40 known compounds include nine clerodane-type diterpenoids,casearvestrin B(17),casearlucine A(18),rel-(2R,5S,6S,8R,9R,1OS,18R,19S)-18,19-diacetoxy-18,19-epoxy-2-(3-methylbutanoyloxy)-6-hydroxycleroda-3,12(Z),14-triene(19),bucidarasin A(20),corymbotin H(21),18β,19β-diacetoxy-18,19-epoxy-2β,6β-dihydroxy-cleroda-3,12E,14-triene(22),rel-(2S,5R,6R,8S,9S,10R,18S,19R)-6,18,19-triacetoxy-18,19-epoxy-2-(2-methylbutanoyloxy)-cleroda-3,12,14-triene(23),6β-hydroxyzuelanin-2a-acetate(24),and rel-(2R,5S,6S,8R,9R,1OS,18R,19S)-18,19-diacetoxy-18,19-epoxy-2-butanoyl oxy-6-hydroxycleroda-3,12,14-triene(25),six megastigmane derivatives,(3R,6R,7E)-3-hydroxy-4,7-megastigmadien-9-one(26),(6R,7E,9S)-9-hydroxy-4,7-megastigma-dien-3-one(27),dehydrovomifoliol(28),(6R;7E,9R)-9-hydroxy-4,7-megastigma-dien-3-one(29),3p-hydroxy-5a,6a-epoxy-7-megastigmen-9-one(30),and(6R,9R)-9-hydroxy-4-megastigmen-3-one(31),seven sesquiterpenoids,4-hydroxy-4,7-dimethyl-l-tetralone(32),polydactin B(33),7-trinoreudesm-4(15),8-dien-1β-ol-7-one(34),canangaterpene Ⅲ(35),4a,7α-Aromodendranediol(36),guaianediol(37),and 4a-methoxyhimachal-10-en-5β-ol(38),three steroids,β-sitosterol(39),7β-hydroxysitosterol(40),and 7a-hydroxysitosterol(41),five miscellaneous types of compounds,(5)-5-hydroxy-3,4-dimethyl-5-pentylfuran-2(5H)-one(42),litseachromo-laevane B(43),rel-(1R,2R,6S;7S)-7-(3-oxobutyl)-2-(1-methylethyl)bicyclo[4.1.0]heptan-3-one(44),loliolide(45),and pubinernoid A(46),six aromatic compounds,4-hydroxybenzaidehyde(47),vanillin(48),antiarol(49),butyl benzoate(50),indole-5.5’-dibutoxy-2,2’-bifuran(51),and bis(2-ethylheptyl)phthalate(52),two indole derivatives,indole-3-carboxaldehyde(51)and 3-hydroxyindole(52),as well as a fatty acid and its ester,(E)-8-oxo-9-oactadecenoic acid(55)and ethyl(E)-8-oxo-9-octadecenoate(56).Some compounds were tested for their anti-proliferative activity and quinone reductase inducing activity.Compounds(-)-1 and 5 showed remarkable quinone reductase inducing activity,while compounds 10 and 13 showed significant anti-proliferative activity against the A549 cell line.