N-羟基丁二酰亚胺的制备

本文介绍了制备N-羟基丁二酰亚胺的一般方法，研究了制备N-羟基丁二酰亚胺水合物的工艺方法，以及从一水合N-羟基丁二酰亚胺出发制备高纯度无水N-羟基丁二酰亚胺的方法。     

N-12-羟基硬脂酰氨基酸型表面活性剂的合成与表征

以12-羟基硬脂酸和3种不同类型的天然氨基酸为原料,采用N,N′-二环己基碳酰亚胺(DCC)和N-羟基丁二酰亚胺(NHS)作为偶合剂,合成了3种具有代表性的N-12-羟基硬脂酰氨基酸(酸性、中性和碱性)表面活性剂。首先,12-羟基硬脂酸和N-羟基丁二酰亚胺反应制得N-羟基琥珀酰亚胺12-羟基硬脂酸酯(产率85%以上),然后将后者与氨基酸进行缩合反应得到了N-12-羟基硬脂酰氨基酸表面活性剂。其较佳合成工艺条件为:N-羟基琥珀酰亚胺12-羟基硬脂酸酯与氨基酸摩尔比为1∶1,室温反应,反应时间不少于4 h,以丙酮与水体积比1∶1为混合溶剂,产率达到80%。利用IR、元素分析和1HNMR对所得产物进行表征,确定了产物结构。     

脱水法制备无水N-羟基丁二酰亚胺

介绍了制备N 羟基丁二酰亚胺的一般方法 ,研究了采用丁二酸酐与盐酸羟胺制备N 羟基丁二酰亚胺水合物的工艺方法 ,以及从一水合N 羟基丁二酰亚胺出发制备高纯度无水N 羟基丁二酰亚胺的方法     

N-羟基丁二酰亚胺合成研究

研究了采用一步法合成N-羟基丁二酰亚胺的工艺,并对各种反应条件进行了研究。当反应温度40℃,n盐酸羟胺∶n丁二酸酐为1∶1.2,高真空除水,合成收率达75.3%,产品纯度≥99.5%。     

N-(9H-芴-9-甲氧羰基氧)丁二酰亚胺合成研究

9-芴甲醇与光气反应合成9-芴甲酯(FMOC-Cl),不经分离直接与N-羟基丁二酰亚胺反应,一锅法合成N-(9H-芴-9-甲氧羰基氧)丁二酰亚胺(FMOC-OSu),总收率95%,产品纯度98%。     

导读

正王琪等采用六羟甲基三聚氰胺、丙烯酸为原料,1-乙基-(3-二甲基氨基丙基)碳酰二亚胺盐酸盐和N-羟基丁二酰亚胺共同为催化剂,进行酯化反应合成氨基丙烯酸酯大单体。通过红外光谱对合成的氨基丙烯酸酯大单体进行表征,并分别对酯化反应的催化剂用量、最佳反应时间、最佳反应温度和六羟甲基三聚氰胺与丙烯酸的最佳反应配比进行了研究。     

N-氯代丁二酰亚胺的合成工艺研究

本文对N-氧代丁二酰亚胺的合成工艺进行了研究。本文改进了加料方法，并确定了冰醋酸的最佳浓度，因此反应收率得到提高。使之更适合于工业生产的要求。     

3,6-二溴咔唑的合成工艺改进

3,6-二溴咔唑是重要的医药中间体,本文采用N-溴代丁二酰亚胺法、液溴法和硅胶法三种方法合成了3,6-二溴咔唑,实验结果表明,硅胶法为较佳路线,并通过正交实验得出最优工艺条件为：室温下反应时间为12h,原料咔唑、N-溴代丁二酰亚胺、溶剂二氯甲烷、催化剂硅胶的用量物质的量比为1：2：131：47时,产品平均收率可提高到89．25％。同时,通过单因素实验对原料配比、反应时间、溶剂用量和催化剂用量四种因素对反应的影响进行了研究。     

六羟甲基三聚氰胺与丙烯酸水相酯化反应的研究

采用六羟甲基三聚氰胺(HMM)、丙烯酸(AA)为原料,1-乙基-(3-二甲基氨基丙基)碳酰二亚胺盐酸盐(EDCI)和N-羟基丁二酰亚胺(NHS)共同为催化剂,进行酯化反应合成氨基丙烯酸酯大单体。通过红外光谱对合成的氨基丙烯酸酯大单体进行表征,并分别对酯化反应的催化剂用量、最佳反应时间、最佳反应温度和六羟甲基三聚氰胺(HMM)与丙烯酸(AA)的最佳反应配比进行了研究。     

N-苯基马来酰亚胺的合成研究

以苯胺和顺丁烯二酸酐为原料,以磷钨酸为催化剂、磷酸为脱水剂、对苯二酚为阻聚剂,两步法进行N-苯基马来酰亚胺合成.研究了原料配比、反应时间和催化剂用量等因素对产品收率的影响,采用正交实验方法确定了最佳工艺条件,使N-苯基马来酰亚胺的收率达到85%以上.     

N-(α-苯氧基)十四酰牛磺酸钠的合成

以α-溴代十四酸乙酯、苯酚、牛磺酸为原料,经W illiam son醚化,水解,催化酰化等反应制备了一种芳氧基作疏水基团支链的牛磺酸盐类表面活性剂,即N-(α-苯氧基)十四酰牛磺酸钠(SPTT)。研究了W illiam son醚化制备α-苯氧基十四酸乙酯的反应条件,考察了几种常用酰化方法对于合成N-(α-苯氧基)十四酰牛磺酸钠的可行性。研究结果表明,醚化反应的最佳条件为:n(α-溴代十四酸乙酯)∶n(苯酚)∶n(K2CO3)=1.05∶11∶,DMF为溶剂,用苯回流分水3 h,α-苯氧基十四酸乙酯的收率为78.3%;合成N-(α-苯氧基)十四酰牛磺酸钠(SPTT)的最佳方法是催化酰化法,即在二环己基碳二亚胺(DCC)和N-羟基丁二酰亚胺(NHS)的催化下,α-苯氧基十四酸与牛磺酸及碳酸钠反应,n(α-苯氧基十四酸)∶n(DCC)∶n(NHS)∶n(牛磺酸)∶n(碳酸钠)=1∶1∶1∶1.5∶1.5,收率为72.3%。中间体及产物经FTIR,1HNMR,ESI-MS等表征,符合结构特征。     

ZnO nanosphere fabrication using the functionalized polystyrene nanoparticles for dye-sensitized solar cells

The nano-hollow spherical ZnO (NHS ZnO) photoelectrodes were prepared using functionalized polystyrene nanoparticles with flexible dimensional control of the particle diameter for dye-sensitized solar cells applications. NHS ZnO was formed by ZnO nanoparticles that accumulated on the surface of functionalized polystyrene with a high ionic strength. This method represents a one-step preparation method for an inorganic shell via polymerization between ZnO complexes. Even though NHS ZnO has a submicron size, it composed of nanoparticles that connect with each other, thereby implying good electron transfer properties, and has a high surface area. The submicron-sized diameter NHS ZnO has an enhanced light scattering capacity, which promotes the photons with more opportunities to be absorbed by the N719 dye molecules. Therefore, the ZnO films prepared from 600 nm to 1000 nm NHS ZnO possessed higher IPCE values over a wide range (from 400 nm to 750 nm) compared to films of the 300 nm ZnO due to the enhanced light scattering capacities of the film. In photocurrent-voltage measurements, the short-circuit current density of 300 nm and 600 nm NHS ZnO increases from 3.33 mA/cm² to 6.53 mA/cm² while the cell efficiency increases from 1.04% to 3.02% due to the light scattering efficiency. Electrochemical impedance spectroscopy showed that electrons in NHS ZnO with a larger particle size have a longer electron lifetime than NHS ZnO with a smaller particle size, as the latter hinders the electron transport in the NHS ZnO nanostructured films.     

Stabilizing effect of carbodiimide and dehydrothermal treatment crosslinking on the properties of collagen/hydroxyapatite scaffolds

This paper reports the effect of the combined technique of dehydrothermal treatment (DHT) and a mixture of 1‐ethyl‐3(3‐dimethylaminopropyl) carbodiimide (EDC) and N‐hydroxysuccinimide (NHS) crosslinking on the physicochemical properties of collagen/hydroxyapatite materials. Collagen and collagen/hydroxyapatite porous scaffolds containing different amounts of collagen and hydroxyapatite were prepared with use of the freeze‐drying technique. All samples were capable of absorbing a large quantity of phosphate buffered saline. Samples crosslinked by DHT+EDC/NHS presented higher resistance to collagenase degradation (with slightly reduced degradation in DHT+EDC/NHS crosslinked scaffolds prepared from 2% collagen solution), whereas DHT scaffolds exhibited faster degradation. Mechanical testing results suggested that scaffolds crosslinked by DHT+EDC/NHS treatment have an improved compressive modulus compared with EDC/NHS crosslinking. The qualitative analysis of colour intensity resulting from the CellTiter 96 Aqueous One Solution Cell Proliferation Assay (MTS) led to the conclusion that all samples, regardless of the crosslinking method, were well tolerated by cells. However, DHT and EDC/NHS crosslinked scaffolds seem to support better cell viability, in contrast to DHT+EDC/NHS crosslinked scaffolds that support cell differentiation instead. DHT+EDC/NHS crosslinked scaffolds markedly increase the specific alkaline phosphatase activity of cells, which may be of benefit in bone tissue engineering. © 2017 Society of Chemical Industry     

Corneal Stromal Cell Growth on Gelatin/Chondroitin Sulfate Scaffolds Modified at Different NHS/EDC Molar Ratios

A nanoscale modification strategy that can incorporate chondroitin sulfate (CS) into the cross-linked porous gelatin materials has previously been proposed to give superior performance for designed corneal keratocyte scaffolds. The purpose of this work was to further investigate the influence of carbodiimide chemistry on the characteristics and biofunctionalities of gelatin/CS scaffolds treated with varying N-hydroxysuccinimide (NHS)/1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) molar ratios (0–1) at a constant EDC concentration of 10 mM. Results of Fourier transform infrared spectroscopy and dimethylmethylene blue assays consistently indicated that when the NHS to EDC molar ratio exceeds a critical level (i.e., 0.5), the efficiency of carbodiimide-mediated biomaterial modification is significantly reduced. With the optimum NHS/EDC molar ratio of 0.5, chemical treatment could achieve relatively high CS content in the gelatin scaffolds, thereby enhancing the water content, glucose permeation, and fibronectin adsorption. Live/Dead assays and interleukin-6 mRNA expression analyses demonstrated that all the test samples have good cytocompatibility without causing toxicity and inflammation. In the molar ratio range of NHS to EDC from 0 to 0.5, the cell adhesion ratio and proliferation activity on the chemically modified samples significantly increased, which is attributed to the increasing CS content. Additionally, the materials with highest CS content (0.143 ± 0.007 nmol/10 mg scaffold) showed the greatest stimulatory effect on the biosynthetic activity of cultivated keratocytes. These findings suggest that a positive correlation is noticed between the NHS to EDC molar ratio and the CS content in the biopolymer matrices, thereby greatly affecting the corneal stromal cell growth.     

Polysaccharide‐based artificial extracellular matrix: Preparation and characterization of three‐dimensional,macroporous chitosan,and heparin composite scaffold

Scaffold‐guided tissue engineering based on synthetic and natural occurring polymers has gained many interests in recent year. In this study, the development of a chitosan‐heparin artificial extracellular matrix (AECM) is reported. Three‐dimensional, macroporous composite AECMs composed of heparin (Hep) and chitosan (Chito) were prepared by an interpolyelectrolyte complex/lyophilization method. The Chito‐Hep composite AECMs were, respectively, crosslinked with glutaraldehyde, as well as cocrosslinked with N,N‐(3‐dimethylaminopropyl)‐N′‐ethyl carbodiimide (EDC/NHS) and N‐hydroxysuccinimide (NHS). The crosslinking reactions were examined by FT‐IR analysis. In physiological buffer solution (PBS), the EDC/NHS‐crosslinked Chito‐Hep composite AECM showed a relative lower water retention ratio than its glutaraldehyde‐crosslinked counterparts. The EDC/NHS‐crosslinked Chito‐Hep composite AECMs showed excellent biocompatibility, according to the results of the in vitro cytotoxic test. This result suggested that the EDC/NHS‐crosslinked Chito‐Hep composite AECMs might be a potential biomaterial for scaffold‐guided tissue engineering applications. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Synthesis of nanostructured Nd:Y2O3 powders by carbonate-precipitation process for Nd:YAG ceramics

Neodymium doped yttria (Nd:Y₂O₃) nanopowders were synthesized by a co-precipitation method, and the effect of thermal decomposition behavior of the precursors were studied. Nonlinear and linear heating schedules (NHS and LHS) were adopted during the calcination processes. The results show that as compared to the LHS the NHS can not only lower the crystallization temperature substantially, but also decrease the mean particle size and lighten the particle agglomeration in the obtained Nd:Y₂O₃ nanopowders. Using the obtained well-dispersed Nd:Y₂O₃ and commercial Al₂O₃ powders, transparent Nd:YAG ceramics were fabricated at 1750 °C in vacuum. Better transparency can be obtained by using the Nd:Y₂O₃ powders calcined in the NHS instead of the LHS.     

Immobilization of α-chymotrypsin to a temperature-responsive reversibly soluble–insoluble oligomer based on N-isopropylacrylamide

A temperature-responsive N-isopropylacrylamide (NIPAAm) oligomer with an ester functional end group and a molecular weight of 3300 was prepared by chain-transfer polymerization using β-mercaptopropionic acid and subsequently activated by N-hydroxysuccinimide (NHS). This oligomer was coupled to α-chymotrypsin to yield a thermo-sensitive reversibly soluble–insoluble oligomer–enzyme conjugate, which is water-soluble at temperatures below 34°C and that precipitates above 36°C. The conjugated enzyme showed higher activity, and improved thermal stability compared with native enzyme. Kinetic properties and optimum conditions for activity were compared with those of native enzyme. More than 93% enzyme activity of the conjugate was recovered after eight cycles of thermal-induced precipitation. The oligomer–enzyme complex was used for repeated hydrolysis of casein; the biocatalyst was recovered between runs by thermal-induced precipitation and showed good stability. © 1998 Society of Chemical Industry     

Polysaccharide‐based artificial extracellular matrix: Preparation and characterization of three‐dimensional,macroporous chitosan and chondroitin sulfate composite scaffolds

Scaffold‐guided tissue engineering based on synthetic and natural occurring polymers has gained much interest in recent years. In this article, the development of a polysaccharide‐based artificial extracellular matrix (AECM) is reported. Three‐dimensional, macroporous composite AECMs composed of chondroitin sulfate (ChS) and chitosan (Chito) were prepared by an interpolyelectrolyte complex/lyophilization method. The ChS–Chito composite AECMs were crosslinked with glutaraldehyde and calcium ions (Ca²⁺) and cocrosslinked with N,N‐(3‐dimethylaminopropyl)‐N′‐ethyl carbodiimide (EDC) and N‐hydroxysuccinimide (NHS). The crosslinking reactions were examined with Fourier transform infrared analysis. Glutaraldehyde and Ca²⁺ crosslinked with Chito and ChS, respectively, to produce different types of ChS–Chito semi‐interpenetrated networks. In contrast, EDC/NHS crosslinked with both Chito and ChS to produce ChS–Chito connected networks. In physiological buffer solutions, the Ca²⁺‐crosslinked ChS–Chito composite AECMs showed a lower swelling ratio than their EDC/NHS‐ and glutaraldehyde‐crosslinked counterparts. The ChS–Chito composite AECMs showed excellent antibacterial capability and biocompatibility according to the results of the in vitro antibacterial test and cytotoxic assay. This result suggested that the ChS–Chito composite AECMs might be a potential biomaterial for scaffold‐guided tissue‐engineering applications. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Bioinspired and biocompatible adhesive coatings using poly(acrylic acid)‐grafted dopamine

Poly(acrylic acid) (PAA) was grafted with dopamine to increase its adhesion force to metal surface. Nitinol plate surfaces were then modified by coating with PAA‐g‐dopamine. To synthesize PAA‐g‐dopamine, PAA was first activated by dicyclohexylcarbodiimide and N‐hydroxysuccinimide (NHS) to form PAA–NHS. Dopamine was then copolymerized with PAA–NHS in an aqueous medium at pH 8.5. We propose to increase the adhesion of adhesive PAA‐g‐dopamine on nitinol to improve its durability. In this article, we studied wettability, surface elemental composition, and surface morphology. Biocompatibility was also assessed by L929 fibroblast cells in vitro. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

N-acryloxysuccinimide: Synthesis, characterization, and incorporation in dental adhesives

In an attempt to enrich the world of dentistry through the development of new materials, this study proposes to synthesize and incorporate a monomer containing the N-hydroxysuccinimide (NHS) ester reactive group to a dental adhesive. As such, this study developed a simple method to obtain NHS esters by employing acrylic acid (AA) and NHS in the presence of EDC (N-ethyl-N′-(3-dimethylaminopropyl)carbodiimide), from an aprotic medium. The experimental N-acryloxysuccinimide (NSA) monomer was analyzed by infrared spectroscopy (FTIR) and nuclear magnetic resonance of hydrogen (¹H NMR). This monomer was then incorporated within a prepared dental adhesive, in a 5% proportion. The modified adhesive, containing NSA, was applied to the dental surface of bovine teeth to obtain an adhesive/dentin interface in vitro. The characterization of this interface by Raman spectroscopy presented the formation of new amide bonds. Moreover, through scanning electron microscopy (SEM), it became possible to observe an intense penetration of this modified adhesive on the dental surface. Considering the outcome, it can be concluded that the synthesized NSA monomer provided a favorable condition for the dental adhesives to interact chemically with the dentin collagen fibers.