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桑椹系桑科(Moraceae)桑属(Morus)植物桑(Morus alba L.)的果穗。桑椹味甜汁多,是常食用的水果之一,也可入药。据《神农本草经》记载,桑椹性寒,味甘、酸,具有滋阴补血、生津止渴等功效,可用于治疗糖尿病、高血压和肝肾损伤等。现代药理研究表明,桑椹提取物具有抗氧化、降血糖、抗肿瘤、抗炎、提高免疫等活性。课题组前期研究发现桑椹中的酚类化合物具有很好的降糖和抗氧化活性,本论文在前期研究的基础上对干燥的桑椹70%乙醇提取物用30%的甲醇混悬后依次用环己烷和氯仿萃取,选择氯仿萃取部位通过硅胶、ODS、Sephadex LH-20及半制备液相等各种色谱方法进行分离纯化,共得到74个单体化合物。利用多种波谱技术并结合化合物的理化性质鉴定了其结构。化合物的结构分别鉴定为:(2S,2’’S)-2,3,8,9-tetrahydro-5-hydroxy-8-(1-methylethenyl)-2-(4-hydroxyphenyl)-4H-furo[2,3-h]-1-benzopyran-4-one(1*),(2S)-7,4’-dihydroxy flavanone(2),(2S)-naringenin(3),(2R)-7,2’,4’-trihydroxy-8-γ,γ-dimethylallyl flavanone(4),(2R)-eriodictyol(5),(2R,3R)-dihydroquercetin(6),kaempferol(7),quercetin(8),artonin ZA(9),isobavachalcone(10),morachalcone(11),(7S,8R)-erythro-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-propanediol(12),(7S,8S)-threo-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2-methoxy phenoxy]-1,3-propanediol(13),(7R,8S)-erythro-7,9,9’-trihydroxy-3,3’-dimethoxy-8-O-4’-neolignan-4-O-β-D-glucopyranoside(14),(7S,8R)-erythro-7,9,9’-trihydroxy-3,3’-dimethoxy-8-O-4’-neolignan-4-O-β-D-gluco pyranoside(15),(7S,8S)-threo-7,9,9’-trihydroxy-3,3’-dimethoxy-8-O-4’-neolignan-4-O-β-D-glucopyranoside(16),(7R,8S)-erythro-4,7,9,9’-tetrahydroxy-3,3’-dimethoxy-8-O-4’-neolignan-9’-O-β-D-glucopyranoside(17),(7R,8S)-erythro-4,7,9,9’-tetrahydroxy-3,5,3’-trimethoxy-8-O-4’-neolignan-9’-O-β-D-glucopyranoside(18*),(7S,8R)-4,9-dihydroxy-3,3’-dimethoxy-7,8-dihydrobenzofuran-1’-propylneolignan(19),(+)-(l R,2S,5R,6S)-2,6-di(4’-hydroxyphenyl)-3,7-dioxablcyclo(3,3,0)octane(20),pinoresinol(21),syringaresinol mono-β-D-glucoside(22),(3R)-thunberginol C(23),7-hydroxy coumarin(24),esculetin(25),7-hydroxy-6-methoxy coumarin(26),cinnamic acid(27),phydroxycinnamic acid(28),caffeic acid(29),ferulic acid(30),cis-cinnamic acid(31),cis-p-hydroxycinnamic acid(32),p-hydroxy phenylpropionic acid(33),frambinone(34),(1’’R,2’’R)-4-(2-formyl-1Hpyrrol-1-yl)-1-(2-hydroxy-1-methylpropoxy)butane ate(35*),4-[formyl-5-(methoxymethyl)-1H-pyrrol-1-yl]butanoic acid(36),4-[formyl-5-(methoxymethyl)-1H-pyrrol-1-yl]butanoate(37),(4’S,5’R)-1-[(tetrahydro-4-hydroxyl-5-oxo-2-furanyl)methyl]-2,4(1H,3H)pyrimidinedione(38*),3-hydroxy-β-carboline(39),1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid(40),isoperlolyrine(41),pistaciamide(42),β-ethyl N-benzoyl-DL-asparlate(43),benzoic acid(44),p-hydroxyl benzoic acid(45),3,4-dihydroxyphenyl aldehyde(46),protocatechuic acid(47),methyl3,4-dihydroxy benzoate(48),ethyl 3,4-dihydroxybenzoate(49),4-hydroxy-3-methoxybenzoic acid(50),4-hydroxybenzaldehyde(51),2,4-dihydroxybenzaldehyde(52),methyl 4-hydroxybenzoate(53),ethyl4-hydroxybenzoate(54),methyl 2-O-β-D-glucopy ranosylbenzoate(55),benzyl-O-β-D-glucopyranoside(56),eugenyl-O-β-D-glucopy ranoside(57),5,7-dihydroxychromone(58),alternariol(59),alternariol 9-methyl ether(60),stemphyperylenol(61),(6R)-5β-(6,7-dihydroxyethyl)-4-(5’-hydroxymethyl-furan-2-yl-methylene)-2β-ethoxy-dihydrofuran-3-one(62),5-hydroxymethylfurfural(63),2-deoxy-D-ribono-1,4-lactone(64),(22E)-5α,8α-epidioxyergosta-6,9(11),22-trien-3β-ol(65),(22E)-5α,8α-epidioxy ergosta-6,9,22-dien-3β-ol(66),(24R)-6β-hydroxy-24-ethylcholest-4-en-3-one(67),(2Z,4E)-(S)-(+)-abscisic acid(68),(2E,4E)-(S)-(+)-abscisic acid(69),(S)-(+)-1-methyl-abscisic-6-acid(70),phaseic acid(71),1,3-dihydroxypropan-2-yl tetradecanoate(72),ethyl-9,12,13-trihydroxy octadeca-10(E),15(Z)-dienoate(73),ethyl-9,12,13-trihydroxyoctadec-10(E)-enoate(74)。其中1-11是黄酮类化合物,12-34是苯丙素类化合物,35-43是含氮化合物,44-61是简单酚类化合物,62-64是呋喃类化合物,65-67是甾醇类化合物,68-71是倍半萜类化合物,72-74是脂肪酸,1、18、35、38为4个新化合物。对部分单体化合物的体外抗炎、抗氧化及抑制α-葡萄糖苷酶活性进行了评价。化合物5、7、9及19具有较强的抑制LPS诱导BV-2细胞NO释放活性(IC50<50μM);化合物1、5、9和19能剂量依赖性地降低i NOS和COX-2的表达,并能阻断LPS诱导的核因子κB(NF-κB)核转移。黄酮类化合物普遍展示了较强的氧化自由基吸收能力(0.80-1.80μmol TE/μmol);化合物5和8具有显著的清除DPPH自由基能力(IC50<10μM)。化合物7、8、10和11具有显著的α-葡萄糖苷酶抑制活性(IC50<50μM)。