聚乙二醇-聚苯乙烯接枝共聚物的合成及其接肽反应性能

本文应用环氧乙烷在羟乙基树脂上的开环聚合方法,合成了凝胶和大孔型聚乙二醇-聚苯乙烯接枝共聚物(简称PEG树脂)。对不同类型载体的接肽反应动力学性能研究表明,在PEG树脂载体上的反应速度是在氯甲基化树脂上的三倍,与在溶液中进行的接肽反应速率相当。此外,还对载体性能与树脂交联度、骨架结构之间的关系进行了初步探索。     

Rink Amide树脂结构对多肽合成的影响研究

研究了Rink Amide树脂取代度、溶胀度及肽链的长度不同对肽合成收率的影响,并对影响Rink Amide树脂溶胀度的因素进行了研究,结果表明,合成长肽时低取代度、高溶胀度的Rink Amide树脂能获得较好的肽收率。     

SYNTHESIS AND BIOLOGICAL ACTIVITY OF A NEW FROG SKIN PEPTIDE, RANAMARGARIN

A new frog skin peptide, ranamargarin depicted as H-Asp-Asp-Ala-Ser-Asp-Arg-Ala-Lys-Lys-Phe-Tyr-Gly-Leu-Met-NH_(2′), was synthesized by the conventionalmethod. Comparisons of chemical and biological properties of both the synthetic and natural ranamargarins indicated that they were identical, so the chemical structure of ranamargarin was confirmed. Preliminary pharmacological study showed that ranamargarin was highly selective towards the SP-P subtype receptor.     

以甘-谷二肽为构筑单元的扇形树状分子的合成与表征

以天然氨基酸为结构单元的树枝状化合物已有不少报道．例如，Denkewalter等首次报道了以氨基酸（L-赖氨酸）为结构单元的1～10代树枝状高分子的合成．Chapman等采用发散法合成了核心为聚氧乙烯（PEO）长链的树枝状t-Boc-聚（α，ε-L赖氨酸）．Kim等报道了两种具有光活性的由缬氨酸或亮氨酸组成的小肽树状分子．Tam等合成了一系列具有各种潜在生物医学用途的肽链结构树枝状分子．     

固相多肽合成中王树脂和Fmoc/tBu酪氨酸成酯反应的研究

以Fmoc/tBu酪氨酸和王树脂为原料,分别探讨了对称酸酐法、活化酯法和2,6-二氯苯甲酰氯(DCB)法中各种因素对氨基酸与树脂成酯反应的影响。实验表明:对称酸酐法连接率低,而其它两种方法,通过筛选合适的反应介质,均能取得良好结果。在活化酯法中,使用强极性溶剂DMA,弱极性溶剂THF/DCM和混合溶剂45%DMF/THF,反应5h,连接率均可提高到90%以上;在DCB法中,使用弱极性溶剂THF时,反应3h,连接率可达99%。总之,DCB方法是酪氨酸和王树脂成酯反应的最好方法。     

反式氢化茚酮的合成在全合成甾体上的应用

反式氢化茚酮是全合成甾体的合成子。本文综述了五种合成方法:即分子内 Diels-Alder 反应,分子内 Michael 反应;联合 Cope-Claisen 重排;Lewis 酸催化环合γ,δ-不饱和羰基化合物以及二环庚烷的裂解。     

IDENTIFICATION OF PARTIAL MUTATIONAL SITES IN HUMAN MITOCHONDRIAL DNA IN THE CHINESE AND ITS SIGNIFICANCE

A simple method for the identification of mutational sites in human mitochondrial DNA (mtDNA) was described. It was based on the human Cambridge sequence as a relative standard sequence and a single base pair substitution in mtDNA as a unique mutational form. The partial mutational sites can be determined using this method which was characterized by combining the restriction mapping with the analysis for the table of human mtDNA potential mutational sites with rapidity and simplicity. In the meanwhile, six mtDNA mutational sites found in Chinese population were identified by means of this method.     

二氧化硫脲的制备及其在有机合成中的应用

本文简要论述了二氧化硫脲的特性、制备方法及其作为新型还原剂在有机合成中的应用。     

POTENTIATED EFFECT OF VAGAL STIMULATION AND HORMONAL AGENTS ON PANCREATIC EXOCRINE SECRETION IN DOGS

Chronic experiments were made on eighteen dogs with Thomas pancreatic fistula andgastric fistula. Both in chronic and acute experiments the degenerated right cervical vagusnerve was stimulated by electrical shock and the endogenous secretin and CCK was releasedby means of duodenal acidification (D. A.). The exogenous secretin, atropine and lidocainewere infused to analyse the interrelationship of neurohormones in the pancreatic exocrinesecretion. The results were as follows. In chronic experiments the pancreatic secretory la-tency was shorter and volume larger than that in acute experiments induced by D. A. Thedifference is very significant (P<0.001). Both vagotomy and atropine significantly inhibitedpancreatic secretion induced by D. A. (P<0.01). Lidocaine infused into duodenum inhibitedpancreatic secretion induced by D. A. as well. When vagal stimulation was combined withD. A., either simultaneously or successively, the pancreatic secretion was increased morethan the additive sum obtained by separate     

TOTAL SYNTHESIS OF Trichosanthes TRYPSIN INHIBITOR AND ITS ANALOGUE

Trichosanthes trypsin inhibitor (TTI) is a peptide consisting of 27 amino acid residues with three pairs of disulfide bonds. This paper reports the total synthesis and disulfide bond refolding of this inhibitor and its analogue. After purification, the amino acid sequence and stoichiometrical inhibitory activity against trypsin of the synthetic inhibitor were compatible with those of the natural inhibitor. The analogue of this inhibitor in which residue Met in position 6 was replaced by Ala was also synthesized. The antitrypsin activity of this synthetic analogue was also approximate to that of the natural inhibitor.     

CLONING, EXPRESSION AND CHARACTERIZATION OF Pro3 GENE OF YEAST Saccharomyces cerevisiae

The proline biosynthetic pathway and Pro genes in Saccharomyces cerevisiae have just begun to be studied recently. In our laboratory, Pro2 gene of S. cerevisiae had been cloned in yeast. As described in this paper, yeast Pro3 gene was also cloned, which can complement yeast Pro3 mutants, and be expressed efficiently in E. coli. The high activities of this gene product, L-pyrroline-5-carboxylate (P5C) reductase, can be detected in both organisms. The activity of the Pro3 gene product in multiple copy plasmids is not higher than that of single copy genes in chromosomes in both yeast and E. coll. The preliminary characterization of the gene is also reported.     

可逆与不可逆吸附氢在合成甲醇反应中的作用

在自行设计和建立的加压动态分析装置上研究了合成甲醇催化剂上氢的吸附和反应行为。结果表明:在反应条件下催化剂上吸附的氢可分为可逆吸附氢和不可逆吸附氢;不可逆吸附氢又可分为能被CO顶替出来的和不能被CO顶替出来的两部分;能被CO顶替出来的不可逆吸附氢对CO的吸附起促进作用,不能被CO顶替出来的不可逆吸附氢是合成甲醇催化剂必不可少的“组分”或称“促进剂”;同时甲醇的生成是可逆吸附氢与一氧化碳作用的结果。     

在DBU存在下酞菁锰配合物的合成及溶剂影响

在强有机碱１，８－二氮杂双环［５，４，０］十一－７烯（简称ＤＢＵ）存在下，ＭｎＣｌ２与邻二氰基苯在某些二元醇溶剂中可高效合成Ｍｎ（Ⅱ）Ｐｃ（Ｐｃ表示酞菁），同时研究了不同溶剂对合成产物的物种及产率的影响和不同氧化态锰的酞菁配合物在一些醇溶剂中的互变现象     

固相有机合成的聚合物载体材料研究进展

本文介绍了目前固相有机合成中常用的几种载体,简述了常见载体的物理化学性质以及常用的几种表征方法,并叙述了载体的环境效应。     

SYNTHESIS AND CHARACTERIZATION OF MCM-41 IN A NEW SYSTEM OF AGING PRETREATMENT

IntroductionSincethediscoveryofthecrystallinemesoporousM4lSmaterialsbyMobil'Sresearchesll'2],thisareahasattractedmanyscientists.alongthesematerialsthesocalledMCM-41hasbeenthefocusofmostresearchers.TheMCM-41possessesaroplararmyofuniform,unidimensionalmesop…     

冠醚芳酸菁染料的合成及其逆光致变色性

1　引言光致变色是一个或几个物种在吸收光谱显著改变的两个状态之间的可逆性变化,这种变化至少在一个方向是由光的照射引起的,而在另一方向通常则是自发的热变化过程[1]。若颜色较深的物种是热不稳定物种,则该体系称为“正”向光致变色体系,否则称为“逆”向光致变色体系。逆向光致变色体系化合物由于其有色体比较稳定,便于研究其有色体的构造、构型及变色机理,对于探索有机光致变色化合物在光信息存储等高科技领域的应用具有一定意义。我们用冠醚菁染料2-甲基-3-烷基-5,6-并-(15-冠-5)苯并噻唑季铵盐与方酸缩合得到了四个未见文献报道的光…     

EXPRESSION OF SYNTHESIZED HIRUDIN GENE IN YEAST

Hirudin is a sort of polypeptides secreted from the salivary gland of medicinal leech. It is of potential importance in medicine. We designed and synthesized the hirudin gene based on the amino acid sequence of hirudin HV2, and expressed it using the yeast alpha factor expression system. The yeast strain stably carrying the hirudin expression plasmid was deduced by mutagenesis. After its cultivation in rich nutritious medium for 36—48 h, the hirudin expression product secreted into the culture fluid was 10—20 ATU/ml. The HPLCpure hirudin product could be obtained through a simpler purification procedure, its N-terminal amino acid sequence was identical with the natural product, and it showed potent anticoagulant and antithrombin activity. About 3000 ATU of pure hirudin witha specific activity of 6600 ATU/mg could be obtained from 500 ml of culture fluid.     

非水体系中FeZSM-48的合成与表征(英文)

本文首次在非水体系Ｎａ２ＯＳｉＯ２Ｎ２Ｏ３Ｆｅ２Ｏ３Ｈ２Ｎ（ＣＨ２）６ＮＨ２Ｃ２Ｈ５）３Ｎ中合成了ＦｅＺｓＭ４８杂原子分子筛。Ｘ衍射和扫描电镜测试表明产物具有ＺＳＭ４８沸石结构。红外光谱和热重差热分析结果表明Ｆｅ（ＩＩ）进入了分子筛骨架，ＥＳＲ光谱中较强的信号ｇ＝４．３有力地证明了分子筛骨架中存在四面体配位的Ｆｅ（ＩＩ）离子。通过对碱度影响的考察发现反应混合物中适当的碱度有利于产物的生成。产物表面富铁富铝。     

中孔分子筛的合成及作为FT合成催化剂载体的应用

分别用季铵盐和中性一级胺为模板剂，在水热条件下和常温常压下合成了纯Ｓｉ和含Ａｌ的中孔分子筛；用ＢＥＴ，ＸＲＤ，ＳＥＭ等手段表征了它们的孔道和骨架结构，对中孔分子筛的生成机理进行了探讨。研究发现，不同的介质，不同的模板剂以及不同的硅、铝源都可以影响产物的最终结构和稳定性。在碱性介质中用季胺盐作模板剂，用无机硅源的条件下，水热过程是形成中孔分子筛稳定晶格的必要条件。室温条件下合成中孔分子筛，体系的静电作用增强有利于产物结构的稳定。另外，本文以各种中孔分子筛作为催化剂载体担载ＺｒＯ２对ＣＯ加氢反应进行了初步研究，就产物的分布情况和ＺｒＯ２／ＺＳＭ５，ＺｒＯ２／β沸石，ＺｒＯ２／ＨＹ上作了对比。结果表明用中孔分子筛作载体的催化剂和小孔分子筛系列相比对Ｃ＝２～Ｃ＝４有较高的选择性。