Characterization And Bioactivity Of Secondary Metabolites From Caesalpinia Mimosoids And Penicillium Oxalicum

A total of 50 compounds including 20 new ones,were isolated from a medicinal plant Caesalpinia mimosoids Lam.and a strain of Penicillium oxalicum by using chromatographic separation techniques.The structures were elucidated on the basis of NMR,MS,UV,IR,and CD spectroscopy techniques.Some of the new compounds showed antioxidative activities in vitro.The chemical constituents of Caesalpinia mimosoides Lam.were studied systematically,and a total of 45 compounds including 20 new and 25 known ones were isolated by using chromatographic separation techniques.The new compounds were identified as five new flavonoids,mimosoidsone A(1),mimosoidsone B(2),medicarpinol A(3),medicarpinol B(4),and 3’-O-methylophioglonin(5),eleven new dibenzooxocine derivatives,(aR,7S)-and(aS,7S)-7-deoxyprotosappanin B(6a and 6b),(aR,7S)-and(aS,7S)-10-O-methyl-7-deoxyprotosappanin B(7a and 7b),(aR,7S)and(aS,7S)-10,11-di-O-methyl-7-deoxyprotosappanin B(8a and 8b),(aR,7R)-and(aS,7R)-13-O-acetyl-7-deoxyproto-sappanin B(9a and 9b),(aR,7R)-and(aS,7R)-10-O-methyl-13-O-acetyl-7-deoxyprotosappanin B(10a and 10b),and mimosoidsol(11);a cassan diterpenoid,caesaldekarinol G(12);three aliphatic compounds,(Z)-6-ethoxy-2-ethylidene-4-hydroxy-6-oxohexanoic acid(13),(E)-2-(2-ethoxy-2-oxoethyl)but-2-enoic acid(14),and(Z)-2-(2-ethoxy-2-oxoethyl)but-2-enoic acid(15).The 25 known compounds were identified as 16 flavonoids,7-hydroxy-3(2,4’-dimethoxy-benzyl)chromone(16),apigenin(17),liquiritigenin(18),(3R)-7,4’-dihydrohomo-isoflavanone(19),(3R)-2,3-dihydro-7-hydroxy-3[(4’-methoxyphenyl)methyl]-4H-1-benzopyran-4-one(20),7-hydroxy-3-(4’-hydroxybenzylidene)chroman-4-one(21),(3E)-7-hydroxy-3-(3’-hydroxy-4’-methoxybenzylidene)chroman-4-one(22),intricatin-ol(23),(3S)-3-(3’,4’-dihydroxybenzyl)-7-hydroxychroman-4-one(24),4,2’,4’-tri-hydroxychalcone(25),3-deoxysappanchalcone(26),(-)-butin(27),sulfuretin(28),luteolin(29),3-O-methylquercetin(30),and 7-hydroxy-4-chromanone(31);five lignans,episyringaresinol(32),(1R,2S,5R,6S)-2-(4-hydroxyphenyl)-6-(3-methoxy-4-hydroxyphenyl)-3,7-dioxabicyclo[3,3,0]octane(33),(-)-syringaresinol(34),(+)-pinoresinol(35),and[(+)-(1R,2S,5R,6S)-2,6-di(4’-hydroxyphenyl)-3,7-dioxabicyclo[3,3,0]octane(36);two cassane diterpenes,12a-ethoxyl-1α,6α,7β-triacetoxy-5α,14β-dihydroxy-cass-13(15)-en-16,12-olide(37)and neocaesalpin N(38);two phenolic acids,syringic acid(39)and 4-hydroxybenzoic acid(40).Among them,the dibenzooxacins 6a-11 were discovered from this plant for the first time.Some new compounds were screened for the antioxidative activity by quinone reductase assay.Compounds 1,3,4,7-10 and 12-13 showed different degrees of antioxidative activity.The secondary metabolites of Penicillium oxalicum were systematically studied by chromatography and spectroscopy.Five known compounds were obtained,including three steroids,(22E,24R)-5α,8α-epidioxy-24-methylcholesta-6,9(11),22-trien-3β-ol(41),(22E,24S)-5α,8α-epidioxy-24-methyl-cholesta-6,9(11),22-trien-3β-ol(42),and(22E)-5α,8α-epidioxyergosta-6,22-dien-3β-ol(43),and two other compounds,sclerin(44)and leptosphaerone B(45).