【作者】 戴毅；

【导师】 姚新生； 栗原博； 周光雄；

【作者基本信息】 沈阳药科大学 ， 药物化学， 2006， 博士

【摘要】 火棘[Pyracantha fortuneana（Maxim．）Li]，为蔷薇科火棘属常绿野生灌木，广泛分布于我国南部及西北地区。其果实作为传统中药，具有健脾消积，生津止渴的功效，常用于治疗消化不良。近期药理学研究发现，火棘具有抗氧化，显著改善大鼠脂代谢等作用。此外，火棘果实提取物能够抑制酪氨酸酶的活性，并将其作为天然美白成分广泛应用于化妆品中。本文综合运用硅胶柱色谱、ODS柱色谱、Sephadex LH-20柱色谱、Toyopearl HW-40柱色谱以及反相MPLC、HPLC等色谱分离手段，以酪氨酸酶抑制活性为指标，对火棘果实60％乙醇提取物的活性成分进行了追踪分离，从中分离得到了34个化合物。通过理化性质和现代波谱学手段(UV、IR、MS、¹H-NMR、¹³C-NMR、2D-NMR)鉴定了它们的结构。它们分别是Fortuneanoside A（1）^*，Fortuneanoside B （2）^*, Fortuneanoside C （3）^*, Fortuneanoside D （4）^*, Fortuneanoside E （5）^*, Fortuneanoside F （6）^*, Fortuneanoside G （7）^*, Fortuneanoside H （8）^*, Fortuneanoside I （9）^*, Fortuneanoside J （10）^*, Fortuneanoside K （11）^*, Fortuneanoside L（12）^*，2，4，6-三羟基-苯乙酮-4-O-β-D-吡喃葡萄糖苷（13），2，4，6-三羟基-苯乙酮-6-O-β-D-吡喃葡萄糖苷（14），Pyrafortunoside A（15）^*，2，4，6-三羟基-二苯基酮-6-O-β-D-吡喃葡萄糖苷（16），Pyrafortunoside B（17）^*，Pyrafortunoside C（18）^*，异槲皮苷（19），金丝桃苷（20），芦丁（21），4′，5，7-三羟基-3′-甲氧基-黄酮醇-3-O-（α-L-吡喃鼠李糖基）-（1-6）-β-D-吡喃葡萄糖苷（22），山奈酚-3-O-（α-L-吡喃鼠李糖基）-（1-6）-β-D-吡喃葡萄糖苷（23），山奈酚-3-O-β-D-吡喃葡萄糖苷（24），山奈酚-3-O-β-D-吡喃半乳糖苷（25），槲皮素（26），山奈酚（27），（+）-表儿茶素（28），苯甲基-O-（α-L-呋喃阿拉伯糖基）-（1-6）-β-D-吡喃葡萄糖苷（29），苯乙基-2′-O-（α-L-呋喃阿拉伯糖基）-（1-6）-β-D-吡喃葡萄糖苷（30），（+）-异落叶松树脂醇-9′-O-β-D-葡萄糖苷（31），熊果酸（32），β-谷甾醇（33），β-胡萝卜苷（34）。其中15个化合物（1-12，15，17-18）为新化合物，11个化合物（13-14，16，22-25，28-31）为首次从火棘属中分离得到。对从活性部位分离得到的化合物进行酪氨酸酶抑制活性实验。结果显示11个化合物（2-10，29-30）表现出不同程度的酪氨酸酶抑制活性。多数联苯糖苷类化合物和二苯并呋喃类化合物具有较好的酪氨酸酶抑制活性，部分化合物的活性强于阳性对照药物熊果苷（arbutin）。活性较强的化合物（4-5，7-10）均含有4′-羟基-3′，5′-二甲氧基结构单元，提示4′-羟基-3′，5′-二甲氧基可能是这类化合物具有活性的结构基础。根据上述结果，我们设计合成了5个联苯类化合物，并测定了它们的酪氨酸酶抑制活性。结果显示具有4′-羟基-3′，5′-二甲氧基结构单元的合成物2、4、5均表现出较强的酪氨酸酶抑制活性。这进一步证实了4′-羟基-3′，5′-二甲氧基结构单元是联苯类化合物具有酪氨酸酶抑制活性的化学结构基础。利用对分离得到的单体化合物的质谱碎裂信息的总结，我们对火棘活性部位进行了LC-MSⁿ研究，从中快速指认了17个已经分离得到的化合物，并利用多级质谱中碎片离子的相对丰度及丢失质量数等信息推测了12个色谱峰的化合物结构。本文通过对火棘中酪氨酸酶抑制活性成分的追踪分离，发现了新的具有酪氨酸酶抑制活性的联苯糖苷类和二苯并呋喃糖苷类化合物，证实了4′-羟基-3′，5′-二甲氧基结构单元是这类化合物具有活性的结构基础，并在此基础上申请的专利。此外，还通过对火棘活性部位的LC-MSⁿ研究，初步建立了快速指认火棘中酪氨酸酶抑制活性成分的方法。这些实验结果为今后对火棘的研究和开发，提供了详实的实验依据。更多还原

【Abstract】 Pyracantha fortuneana (Maxim.) Li, Chinese name Huo-ji, is a evergreen shrub plant of pyracantha roem. genus in rose family, widely distributed throughout the southern and northwestern parts of China. Its fruit is used as a traditional Chinese medicine for treatment of indigestion. Recent pharmacological studies showed that P. fortuneana possessed some antioxidation activities and could significantly improve the lipoprotein metabolism of rats. Its fruit extract showed inhibitory activity against tyrosinase and was widely used in cosmetics as a skin-whitening agent.In our investigation for compounds with inhibitory activity against tyrosinase, 34 compounds were isolated from the 60% ethanol extract of the fruit of this plant through various chromatographic techniques. The structures were established on the basis of their physicochemical properties and spectroscopic analysis as Fortuneanoside A (1)~*, Fortuneanoside B (2)~*, Fortuneanoside C (3)~*, Fortuneanoside D (4)~*, Fortuneanoside E (5)~*, Fortuneanoside F (6)~*, Fortuneanoside G (7)~*, Fortuneanoside H (8)~*, Fortuneanoside I (9)~*, Fortuneanoside J (10)~*, Fortuneanoside K (11)~*, Fortuneanoside L (12)~*, 2,4,6-trihydroxy-acetophenone-4-O-β-D-glucopyranoside (13), 2,4,6-trihydroxy-acetophenone-6-O-β-D-glucopyranoside (14), Pyrafortunoside A (15)~*, 2,4,6-trihydroxy-benzophenone-6-O-β-D-glucopyranoside (16), Pyrafortunoside B (17)~*, Pyrafortunoside C (18)~*, Isoquercitrin (19), Hyperoside (20), Rutin (21),4’,5,7-trihydroxy-3’-methoxy-flavonol-3-O-(α-L-rhamnopyranosyl)-(1-6)-β-D-gluco-pyranoside (22), kaempferol-3-O-(α-L-rhamnopyranosyl)-(1-6)-β-D-glucopyranoside (23), kaempferol-3-O-β-D-glucopyranoside (24), kaempferol-3-O-β-D-galactopyranoside (25), quercetin (26), kaempferol (27), (+)-epicatechin (28), phenylmethyl-O-(α-L-arabinofuranosyl)-(1-6)-β-D-glucopyranoside (29), phenylethyl-2’-O-(α-L-arabinofuranosyl)-(1-6)-β-D-glucopyranoside (30), (+)-Isolarisiresinol-9’-O-β-D-glucopyranoside (31), ursolic acid (32),β-sitosterol (33), and daucosterol (34), respectively. Among them, 15 compounds (1-12, 15, 17-18) were new compounds, and 11 compounds (13-14, 16, 22-25, 28-31) were isolated from the pyracantha genus for the first time.All the compounds isolated from the active fractions were evaluated for inhibitory activity against tyrosinase. The results showed that 11 compounds (2-10, 29-30) possessed inhibitory activity on different levels. Most of biphenyl glycosides and dibenzofuran glycosides showed potent activity, and some of them were more potency compared with arbutin. All the potent compounds possessed the 4’-dihydroxy-3’, 5’-dimethoxy moiety in the structure, suggesting that the special moiety might contribute to the inhibitory activity against tyrosinase.Five biphenyl compounds were synthesized, and evaluated for inhibitory activity against tyrosinase. Some of the synthetic compounds displayed potent activity, which also possessed the 4’-dihydroxy-3’, 5’-dimethoxy moiety in the structure. It confirmed that the special moiety contributed to the inhibitory activity.The LC-MS~n study of the active fraction of the fruit extract was also performed on the basis of MS~n data of the compounds isolated from P. fortuneana. Seventeen peaks in the chromatograph were assigned, and 12 peaks were deduced by the loss of mass and the relative abundance of fragment ions in MS~n data.更多还原