【作者】 郭书举；

【导师】 韩丽君；

【作者基本信息】 中国科学院研究生院（海洋研究所） ， 海洋化学， 2010， 博士

【摘要】 2型糖尿病是一种代谢类综合症,主要特点是胰岛素抵抗、高血糖和高胰岛素血症。实验研究表明,蛋白酪氨酸磷酸酶1B(PTP1B)作为胰岛素转导信号的负调控因子,已经成为治疗2型糖尿病和肥胖症的新靶点。松节藻纲(Rhodomelaceae)海藻富含溴酚类物质,广泛分布于中国、日本、朝鲜半岛及大西洋北岸。在对采自我国青岛沿海的松节藻Rhodomela confervoides的研究中分离得到大量溴酚类化合物,其中四个表现出强烈的抑制蛋白酪氨酸磷酸酶1B(PTP1B)的活性,尤以化合物3-溴-4-[(2′,3′-二溴-4′,5′-二羟基苯基)-甲基]-5-[(乙氧基)-甲基]-1,2-苯二酚(BPN)活性最为明显(IC50=0.84μmol/L)。为了研究BPN的体内降糖活性,本文采用了化学合成的方法来解决化合物的药源问题。1、对松节藻Rhodomela confervoides乙酸乙酯相萃取物进行了分离纯化,采用正相硅胶色谱、凝胶Sephadex LH-20色谱和重结晶等纯化手段,从50 kg松节藻干样品中分离得到9.9 g BPN,同时得到其它结构溴酚类化合物7个。但是,由于松节藻中各类次生代谢产物复杂多样,致使分离纯化过程耗费大量时间和精力。2、对化合物BPN进行了化学合成。以香兰素为原料,通过8步反应(主要包括溴代、Wolff-Kishner-Huang还原、Friedel–Crafts烷基化等反应)成功合成了目标化合物BPN,总产率为14.4%。通过对合成路线中各步反应条件的优化,建立了一条合成该类化合物较理想的路线。通过该路线,制备BPN 35 g,为体内降糖活性研究提供了充足的药源。3、以BPN为先导化合物,以其结构为基本骨架,设计合成了溴酚衍生物31个,其中新化合物26个。合成的化合物经过1HNMR、13CNMR、EIMS及HRESIMS进行了结构鉴定。4、对该类化合物的构效关系进行了初步分析:a.如图所示的溴代二苯甲烷(酮)结构单元是该类化合物显示PTP1B酶抑制活性的基本结构单元,对该结构的破坏将使化合物的活性消失。b.支链R3的类型和长度对化合物的活性起着非常重要的作用。c.化合物的活性随着苯环上溴原子取代的增加而增加。5、对合成的目标BPN进行了动物体内急性毒性试验,受试动物未见急性毒性反应。利用STZ-DM大鼠模型,对化合物BPN进行了体内降糖活性筛选,发现化合物BPN体内降糖活性明显。更多还原

【Abstract】 Type 2 diabetes, is a complex metabolic disease characterized by insulin resistance, hyperglycemia and hyperinsulinemia. Evidence from biochemistry and genetic studies supported that PTP1B, a key negative regulator of insulin signal transduction, was a major target for a novel therapeutic strategy for the treatment of diabetes and obesity.The family Rhodomelaceae, distributed widely in China, Japan, and Korean Peninsula, are known to contain bromophenols. Four bromophenols isolated from Rhodomela confervoides collected at the coast of Qingdao, China, showed potent Protein tyrosine phosphatase 1B (PTP1B) inhibitory activity, especially the compound named 3,4-dibromo-5-(2-bromo-6-(ethoxymethyl)- 3,4-dihydroxybenzyl)benzene -1,2–diol (BPN)(IC50=0.84μmol/L). In order to further study its hypoglycemic activity in vivo, the compound BPN was synthesized.1. 9.9 g BPN and 7 bromophenols were isolated from EtOAc-soluble portion of 50kg red alga R. confervoides by chromatography including normal phase silica gel, Sephadex LH-20 gel and recrystallization. However, it is hard to isolate BPN from R. confervoides, because constituent of R. confervoides makes separation and purification process of BPN taking a lot of money and time.2. The targeting compound BPN was synthesized in 8 steps with an overall yield of 14.4%, employing bromination, Wolff-Kishner-Huang reduction and Friedel-Crafts reaction as key steps. A practical approach was established after the optimization of each reaction. 35 g BPN was synthesized via this synthetic route. 3. 31 compounds (including 26 new compounds) were synthesized and the structures of these compounds were elucidated by spectroscopic methods including 1HNMR, 13CNMR, EIMS and HRESIMS.4. Based on the inhibition of these compounds, the preliminary structure-activity relationships of the screened compounds were revealed as followed:(a). Bromo-diphenyl methane (one) structural unit is necessary for the compounds to behave the PTP1B inhibitory activity. Once the structure is destroyed, the inhibitory activity will disappear.(b). The length of R3 plays an important role in structure-activity relationship of the screened compounds.(c). The increasing of bromine number on benzyl ring could upgrade potency of PTP1B inhibitory activity.5. The acute toxicity test in mice was carried out, and the compound showed no obvious acute toxicity. The oral antihyperglycemic effects of BPN were investigated on streptozotocin-induced experimental diabetes in rats. Oral administration of BPN resulted in a reduction in blood glucose.更多还原