保护基

2 New carbonyl functionalized imide derivatives of maleimide were synthesized by the direct reaction of amino acids with maleic anhydride.

用氨基酸与苹果酸酐直接反应，合成了两个含羧基官能团的苹果酰亚胺，为氨基酸氮端的保护以及含羧基官能团的酰亚胺类化合物的合成提供了一种直接、简便的新方法。

The hydroxy and nitro-substituted coumarins were able to inhibite hemolysis of human red blood cells and damage of DNA induced by AAPH. It reveals that these compounds are effective antioxidants. Some coumarins have cytostatic and cytotoxic activity for HL-60 cell lines. In general, their effects were weakened when coumarins own nitro group.

含有羟基和硝基的香豆素衍生物对自由基诱导的人血红细胞溶血有一定的抑制作用，且对AAPH诱导的DNA损伤有不同程度的保护作用，部分香豆素衍生物对人早幼粒白血病细胞（HL-60）的增殖表现出一定的抑制作用。

ConclusionTroxerutin has the ability to scavenge oxygen free radical and to protect from the damage of ischemia-reperfusion in rat liver.

结论曲克芦丁对肝脏I/R损伤具有保护作用，其机理与抑制氧自由基的生成，增强氧自由基的清除，减轻肝细胞脂质过氧化作用有关。

The synthesis of the pentacyclic skeleton of Et-743 and the construction of the five chiral centers thereof.1. The core pentacyclic skeleton of phthalascidin was constructed with L-dopa as the starting material via thirteen steps. First, two basic synthons, the C-1 functionalized tetrahydroisoquinoline compounds 8 and N-protected Z-dopa derivative 9, were prepared from L-dopa. They were coupled via amide bond to form the dipeptide compounds 10, which were the first key intermediates. Then the primary hydroxyl groups were transformed into the corresponding amino aldehydes 11 via Swern oxidation. Followed by the intramolecular Pictet-Spengler cyclization, the pentacyclic compounds 12 were synthesized.

五环骨架的构建及五个正确手性中心的确立：1.1我们以L-多巴为起始原料，经过多步官能团保护和转化合成了基本结构单元8然后和苯丙氨酸衍生物9，通过缩合反应生成酰胺中间体10，经Swern氧化得到醛化合物11，然后再次利用分子内改良的Pictet-Spengler反应一步构建c，d两环，得到五环骨架化合物12，最后，实现了21-位羰基向氰基的转化，得到了C-1位官能化的化合物14，化合物14不但具有和Et-743一致的五环骨架，而且分子中五个手性中心立体构型也与其完全相同：其中，3，位和13，位的手性中心由原料L-多巴带入，而1，位，11，位和21，位手性中心则通过不对称诱导而确立。

Based on the above-mentioned, two kinds of target glycoclusters with different glycoterminus, flexible linkers and different scaffolds were designed, disaccharide glycocluster (including TM1-TM7) and trisaccharide glycocluster (TM8-TM9) respectively, with the purpose of obtaining glycoclusters with high binding affinity to anti-Gal antibody and thus better inhibiting the HAR.

基于上述，针对HAR产生的机制，以人体中天然存在的anti-α-Gal抗体及B细胞表面的相应受体为靶点，以α-Gal抗原末端的二糖Galα1→3Gal和三糖Galα1→3Galβ1-4GluNAc片段为糖基部分，采用柔性的连接臂（氨基保护的2-乙醇胺和3-巯基丙酸）和刚性的芳香骨架及柔性的脂肪链骨架，设计了两类结构新颖的糖簇分子：即氧苷和硫苷键连接的二糖糖簇TM1-TM7）和三糖糖簇（TM8-TM9），目的在于寻找与anti-Gal抗体及B细胞相应受体有较高结合力的糖簇分子，以便有效地抑制HAR反应的发生。

Poly-[N-(2-hydroxyethyl)-L-glutamine] was then obtained by aminolysis of PBLG with 2-aminoethanol.

以L -谷氨酸为单体，经r -羧基的苄基保护，与光气/甲苯液反应制备L-谷氨酸苄酯的羧酸酐，均聚得L -谷氨酸苄酯，然后经由 2 -氨基乙醇胺解得聚 [N -( 2 -羟乙基)-L -谷酰胺 ] 。

Based on the unique characteristics of the Yellow River and previous research on its ecological water requirement, the present paper recommends that the water requirement for transport in the flood season and base ecological flow in non-flood season should be both included in the ecological water requirement. The water requirement for transport is 80 × 108-120 × 108 m3 per year if the bankfull discharge carries the largest sediment and contaminant load over a long period of time. The base ecological flows in non-flood season at Huayuankou and Lijin stations are 80 × 108-100×108 m3 and 50 × 108-60 × 108 m3, respectively.

通过分析黄河下游1958～2000年实测生态可用水，探讨生态需水量内涵，根据黄河特殊性及黄河生态需水量的研究现状，将维持和保护河流功能的黄河下游生态需水量分为汛期输运水量和非汛期生态基流量，在平滩流量输运能力最强的前提下，估算黄河下游汛期输运水量为80～120亿m3，根据实测资料估算作为黄河下游水量控制断面花园口水文站和作为河口地区水量控制断面利津水文站的非汛期生态基分别为80～100亿m3和50～60亿m3。

Firstly, a series of organic molecules which use phthalimido group as electron acceptor, N as electron donor, COO~- as eletrofugal group were synthesized based on SET-promoted photocyclization processes. These compounds were irradiated by 500 W ultraviolet under nitrogen atmosphere in room temperature. After filtration of the photochemical character of these molecules, substrate S1 and S2 were selected as appropriate model reactants. Secondly, the monosubstituted derivatives at the 6-position ofβ-cyclodextrin were synthesized as chiral template of photocyclization.

首先，以单电子转移机理为指导，设计了一系列以邻苯二甲酰亚胺基为电子受体、N为电子给体、羧基为离去基团的光环合反应底物，这些化合物在氮气保护下以500瓦紫外光室温下进行光照反应，对这一系列的分子的反应情况进行了研究与筛选，最终选择底物S1和S2作为研究光环合反应中立体控制方法的模型底物；其次，又合成了一系列6-位单取代β-环糊精，以此作为光环合反应的手性模板。

To investigate the neuroprotective effect and mechanism of TMB 8[8-(N, N-diethy lamino)- n -octyl- 3,4,5- trimethoxybenzoate].

研究TMB-8[8--n-辛基-3，4，5-三甲氧基苯甲酸酯]的神经保护作用及其可能机制。

Based on relative literatures,this part has included five resesearch aspects as below.1 Fifteen compounds were isolated and purified by extraction,column chromatography,and their structures were determined on the basis of spectral analysis: acteoside(Ⅰ-1),isoacteoside(Ⅰ-2),crenatoside(Ⅰ-3),cistanoside F(Ⅰ-4),sinapoyl-4-O-β-D-glucoside(Ⅰ-5),adenosine(Ⅰ-6),β-siterol(Ⅰ-7),oleanic acid(Ⅰ-8), succinic acid(Ⅰ-9),caffeic acid(Ⅰ-10),protocatechuic aldehyde(Ⅰ-11),p-hydro xybenzyl alcohol(Ⅰ-12),β-daucosterol(Ⅰ-13),D-galacitol(Ⅰ-14),D-mannitol(Ⅰ-15).Ⅰ-4～15 were obtained from this plant for the first time,andⅠ-6,7,9,and 13 were isolated from Orobanche genus for the first time.2 The scavenging test of DPPH showed that most compounds have comparative antioxidant activity as L-ascorbic acid and part of them show better activity such as the O.coerulescens extract and phenylethanoid glycosides.Acteoside showed potent free radical scavenging effects with a median inhibition concentration of 25.6μg/ml.3 The anti-HBV activities of acteoside,isoacteoside and crenatoside were measured,and all of them showed suppressive activity on the expression of HBsAg and HBeAg in the HepG2.2.15 cell line.

本论文在文献调研基础上对紫花列当化学成分及生物活性进行了研究，并从免疫抗病毒角度探讨紫花列当中特征性成分类叶升麻苷的肝保护作用及其机制。1采用大孔树脂、硅胶和Sephadex LH-20等色谱技术对紫花列当进行系统的植物化学研究，从中分离得到19个化合物，利用UV和NMR等波谱手段及理化性质鉴定了其中的15个化合物，分别为类叶升麻苷(Ⅰ-1)、异类叶升麻苷(Ⅰ-2)、crenatoside(Ⅰ-3)、cistanoside F(Ⅰ-4)、sinapoyl-4-O-β-D-glucoside(Ⅰ-5)、腺苷(Ⅰ-6)、β-谷甾醇(Ⅰ-7)、齐墩果酸(Ⅰ-8)、琥珀酸(Ⅰ-9)、咖啡酸(Ⅰ-10)、原儿茶醛(Ⅰ-11)、对羟甲基苯甲酸(Ⅰ-12)、β-胡萝卜苷(Ⅰ-13)、D-半乳糖醇(Ⅰ-14)和甘露醇(Ⅰ-15除化合物Ⅰ-1、Ⅰ-2和Ⅰ-3外，其余化合物均为首次从该植物中分离得到。2)通过大孔树脂富集该药材有效部位苯乙醇总苷，并采用HPLC测得其所含特征性成分类叶升麻苷的含量可达80%以上。3DPPH自由基清除试验显示紫花列当提取物及其所含的苯乙醇苷类化合物均具有较好的抗氧化能力，其清除DPPH自由基能力接近于抗坏血酸。4采用卡介苗整体致敏、脂多糖离体攻击构建大鼠原代肝细胞免疫性损伤模型，在体外观察类叶升麻苷的保肝作用。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。