乳胶微球固定化碱性磷酸酶的研究

本文系统地研究了生物素化碱性磷酸酶在微球载体上的固定化，确定了在胺化聚苯乙烯微球上固载的最适条件，并对所得固相酶的最适ｐＨ值，最适温度，米氏常数Ｋｍ值等性能进行了测试，结果发现生物素化碱性磷酸酶固定于胺化微球后其最适ｐＨ值从９．５降低至９．３；酶的最适温度没有发生变化，但范围稍加宽；在５０℃温度下处理９０分钟，固相酶活化保持在４０％，稳定性增强，固定化后酶的Ｋｍ减小。     

聚苯乙烯阴离子交换树脂固定α—淀粉酶的研究（Ⅱ）

用聚苯乙烯阴离子交换树脂作载体，采用吸附法将ａ一淀粉酶固定化，研究了固定化条件和固定化酶的性能。固定化条件为：酶浓度１０ｍｇ／ｍｌ，固定化ｐＨ６．８，吸附时间１６ｈ，吸附温度６℃。固定化酶的ｐＨ稳定性、热稳定性、贮存稳定性都有一定的提高。最适作用温度及ＰＨ较自由酶为高，Ｋｍ值为自由酶的１．６倍。同时也进行了固定化酶的操作稳定性研究。     

α，ω─二羧基聚乙二醇磁性毫微粒固定化碱性蛋白酶的研究

本文用共沉淀法制备了平均直径为３８４纳米的α，ω─二羧基聚乙二醇磁性毫微粒．碱性蛋白酶通过吸附交联法被固定于磁性毫微粒．研究了制备过程中的吸附时间、给酶量、戊二醛浓度、ｐＨ和离子强度对磁性固定化酶活力及酶固定化率的影响．比较了磁性蛋白酶磁性固定化酶与自由酶的酶学性质，磁性固定化酶的最适温度有改变，但热稳定性显著提高；磁性固定化酶的最适ｐＨ向酸性方向移动了１．０个ＰＨ单位。     

Methylomonas Z201 细胞在戊二醛活化DEAE 纤维素上的共价固定化

以戊二醛活化的ＤＥＡＥ纤维素为载体，采用共价键法固定化ＭｅｔｈｙｌｏｍｏｎａｓＺ２０１细胞．固定化细胞催化丙烯环氧化的最优细胞／载体比为３２ｍｇ干重细胞／（ｇＤＥＡＥ纤维素），最适ｐＨ值和最适温度分别为７．８和３５℃．用纯氧代替空气作为氧源，分别使游离和固定化细胞的ＭＭＯ活性提高了８％和３５％．外源性电子给体甲酸钠对固定化细胞ＭＭＯ活性的激发作用小于游离细胞．失活动力学分析结果表明，固定化细胞的稳定性高于游离细胞．     

α,ω—二羧基聚乙二醇磁性毫微粒固定化碱性蛋白酶的研究

本文用共沉淀法制备了平均直径为３８４纳米的α，ω－二羧基聚乙二醇磁性毫微粒，碱性蛋白酶通过吸附交联法被固定于磁性毫微粒，研究了制备研究中的吸附时间，给酶量，戊二醛浓度，ｐＨ和离子强度对磁性固定化酶活力及酶固定化率的影响。比较了碱性蛋白酶磁性固定化酶与自由酶的酶学性质，磁性固定化酶的最适温度没有改变，但热稳定性显著使高；磁性固定化酶的最适ｐＨ向酸性方向移动了１．０个ｐＨ单位。     

α—胰凝乳蛋白酶的固定化及其对DL—苯丙氨酸的光学拆分

以氨丙基多孔球为载体，戊二醛为交联剂制得固定化α－胰凝乳蛋白酶。其含酶量为３．６ｍｇ／ｇ，米氏常数Ｋｍ＝１．２×１０＾－３ｍｏｌ／Ｌ，最适宜温度为３５℃，ｐＨ值为７．０，对热、酸碱、甲醇以及尿素的稳定性有较大提高，Ｃａ＾２＋激活效应明显。用该固定化酶连续拆分ＤＬ－苯丙氨酸制备Ｌ－苯丙氨酸时，拆分产率高于９０％，产品纯度超过９６％；连续使用２个月后仍能保持较高酶活力。     

谷氨酸脱羧酶在新型羧甲基化交联烯丙基葡聚糖凝胶树脂上的 …

本文首次用合成的羧甲基化的以Ｎ，Ｎ’－甲叉双丙烯酰胺交联的烯丙基葡聚糖（简称ＣＭ－ＣＡＤＢ）凝胶生化树脂为新型载体，研究了谷氨酸脱羧酸在ＣＭ－ＣＡＤＢ树脂上的固定化与环境的信赖关系。确定了酶固定化最佳条件：缓冲体系为ｐＨ４．４，０．１０ｍｏｌ／Ｌ磷酸氢二钠－０．０５ｍｏｌ／Ｌ柠檬酸，载体为交联度３５％，交换容量３．０ｍｅｑ／ｇ的ＣＭ－ＣＡＤＢ凝胶树脂，吸附平衡时间４ｈ以上，酶用量为３０．０ｍｇ／ｇ     

固定化根霉细胞催化拆分(R,S)-环氧丙醇丁酸酯的研究

用聚乙烯醇包埋、硫酸钠固定法对根霉（ Ｒｈｉｚｏｐｕｓｓｐ．Ｂｃ０－０９）菌体细胞进行了固定化,所得凝胶具有良好的机械性和稳定性． 对固定化细胞催化（ Ｒ,Ｓ）－环氧丙醇丁酸酯水解反应的性能进行了研究． 对ｐＨ值的影响考察结果表明, ３０ ℃下, 反应初速度在ｐＨ 值为５．５ 时最大; 酶的立体选择性在ｐＨ值为５．５～６．０ 时最高, 对映体比率（ Ｅ值）为５７． 对温度的影响考察结果表明,ｐＨ 值为５．５, 反应初速度在５５ ℃时最大; 酶的立体选择性随温度升高而下降． 固定化细胞具有较好的操作稳定性．     

L—氨基酸氧化酶电极的制作及电极特性的研究

报道了一种新的Ｌ－氨基酸氧化酶电极，这种酶电极系由氨气敏电极和以氨基化玻璃布为载体的酶膜所组成；研究了固定化条件对酶膜活性的影响以及底物浓度、温度和ｐＨ对电极响应特性的影响。该电极在６．０×１０＾－５～４．０×１０＾－３ｍｏｌ／Ｌ的底物浓度范围内呈良好的线性关系，检测下限为５．０×１０＾－５ｍｏｌ／Ｌ。在最宜条件下，酶电极具有良好的稳定性。     

壳聚糖固定L-天门冬酰胺酶的研究

研究了以壳聚糖为载体，戊二醛为交联剂，固定化Ｌ－天门冬酰胺酶的最适条件，并对固定化天门冬酰胺酶的理化性质进行了初步探讨。分别从不同固定化程序、缓冲液及保护剂等方面进行了固定化天门冬酰胺酶的条件优化；固定化酶的活力回收可达２０％左右。固定化酶的最适范围变宽，由游离酶的最适ｐＨ＝４～６变为ｐＨ＝６～１０。连续使用６次后仍可基本维持固定化酶的活力。固定化酶对胃蛋白酶的水解性也较游离酶大大提高。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.