Particle‐Based Synthesis of Peptide Arrays

High‐density peptide arrays with solid amino acid particles: Intermittent “freezing” of activated amino acid derivatives within solid particles allows a laser printer or a chip to spatially address these “postal packages”. Subsequent parallel coupling is started simply by melting a whole layer of 20 different amino acid particles, freeing the hitherto immobilized amino acids and resulting in the coupling of all 20 different amino acids to the support in a single coupling step.

     

Modification with Organometallic Compounds Improves Crossing of the Blood–Brain Barrier of [Leu5]‐Enkephalin Derivatives in an In Vitro Model System

Enkephalin peptides are thought to be suitable vectors for the passage of the blood–brain barrier (BBB). Modifications that do not alter the amino acid sequence are often used to improve the permeation through living membrane systems. As a new type of modification we introduce organometallic compounds, in particular ferrocene carboxylic acid. Derivatives of [Leu⁵]enkephalin were synthesised and labelled with organometallic compounds by using solid‐phase synthesis techniques. All new metal–peptide bioconjugates were comprehensively characterised by HPLC, NMR spectroscopy and mass spectrometry and found to be at least 95 % pure. For the first time, permeation coefficients in a BBB model for organometal–peptide derivatives were determined in this work. The uptake and localisation of fluorescein‐labelled enkephalins was monitored by fluorescence microscopy on three cancer cell lines. Octanol/H₂O partition coefficients of the compounds were measured by HPLC. The introduction of the organometallic moiety enhances the uptake into cells and the permeation coefficient of [Leu⁵]‐enkephalin. This could be due to an increase in lipophilicity caused by the organometallic label. The metal–peptide conjugates were found to be nontoxic up to mM concentrations. The low cytotoxicity encourages further experiments that could take advantage of the selectivity of enkephalin derivatives for opioid receptors.     

乙醇溶剂法合成N,N′-二仲丁基对苯二胺的研究

以对苯二胺为原料,仲溴丁烷为烷化剂,无水乙醇为溶剂,饱和氢氧化钠水溶液为缚酸剂,采用单分子亲核取代反应合成N,N′-二仲丁基对苯二胺。研究了乙醇加入量、原料摩尔比、反应温度、反应时间等因素对产物收率的影响。结果表明:仲溴丁烷与对苯二胺的摩尔比为2.05,反应温度75°C,反应时间8h,无水乙醇与对苯二胺的质量比是4的条件下,产物收率可达94%～95%。并利用红外光谱对产物进行了表征。     

解吸-热提两步法提取扶芳藤抗氧化物质工艺研究

用解吸-热提两步提取法,以乙醇为解吸剂和热提剂,提取扶芳藤中抗氧化物质,利用响应面实验设计,考察了解吸剂体积分数、解吸剂用量、热提剂用量和T汽化=T热提对抗氧化物质提取的影响。结果表明,优化工艺条件为:解吸剂体积分数为41%,解吸剂用量为4.5 mL,热提剂用量为20 mL,T汽化=T热提为11 min,此时的抑制率为16.78%,与模型预测值基本相符。     

树脂催化法合成抗氧剂2246的研究

以2-叔丁基-4-甲基苯酚和多聚甲醛为原料,采用酸性离子交换树脂催化合成了抗氧剂2246[2,2’-亚甲基双(4-甲基-6-叔丁基苯酚)]。研究了催化剂DNW-1的用量、溶剂用量、反应时间、反应温度和原料的配比对抗氧剂2246的收率及纯度的影响。较佳反应条件为:2-叔丁基-4-甲基苯酚32.8 g,多聚甲醛3.9 g,DNW-1为12 g,正庚烷100 mL,Span 80为0.5 g,在84~86℃下反应4.5 h,收率(质量分数)为94.6%(96.6%)。该工艺减少了废水的排放。     

抗氧剂168的合成工艺研究

研究了酯化法合成抗氧剂168[亚磷酸三（2,4二叔丁基苯基）亚磷酸酯]的工艺条件。以68．8g（1／3mol）2,4-二叔丁基苯酚和15．4g（1／9mol）三氯化磷为原料,催化剂三乙胺,反应温度140—150℃、反应时间2．5h的条件下进行酯化反应,经异丙醇结晶后得三（2,4-二叔丁基苯基）亚磷酸酯。平均收率95％。     

In vitro and in vivo Staining Characteristics of Small,Fluorescent, Aβ42‐Binding D‐Enantiomeric Peptides in Transgenic AD Mouse Models

Plaque visualisation : We identified three different D ‐enantiomeric peptides that bind to Alzheimer's amyloid β (Aβ1‐42). As there is currently no definitive pre‐mortem diagnosis for Alzheimer's disease, we investigated the peptides' suitability as molecular probes for in vivo imaging in transgenic mouse models.

     

橡胶防老剂4010NA合成用催化剂的实验室研究

对N-苯基-对苯二胺（RT培司）和丙酮一步法合成4010NA的专用催化剂进行了试验室研究。研制出强度稳定,RT培司转化率大于或等于98％,4010NA选择性大于或等于95％,且副反应显著降低,脂肪酮回收率大幅提高的催化剂。     

润滑油抗氧剂协同作用研究

对润滑油的氧化机理做了简要阐述,并根据不同的抗氧作用机理,将抗氧剂分为三类:自由基清除剂(如酚类和胺类抗氧剂)、氢过氧化物分解剂(如氨基甲酸酯)和抗氧协合剂(如不含硫磷的钼酸酯).利用加压差示扫描量热法(PDSC)对不同类型抗氧剂以及它们之间的协同作用进行了考察.研究表明,作为氢过氧化物分解剂,改进的无灰氨基甲酸酯具有比胺类、酚类抗氧剂更好的性能,这显示了氢过氧化物分解型抗氧剂巨大的应用潜力.研究还表明,具有相同抗氧机理的不同抗氧剂,如酚类和胺类抗氧剂,具有协同作用;不同作用机理的两抗氧剂之间,如自由基清除剂和氢过氧化物分解剂,具有更好的抗氧化协同效果,其中,无灰氨基甲酸酯与烷基化二苯胺抗氧剂具有最佳的抗氧协同效能,可成为高温无灰抗氧剂应用的一个很好选择;不同抗氧机理的三种抗氧剂复合,如烷基化二苯胺,氨基甲酸锌和有机钼酸酯组成的三元复合抗氧剂,具有更为优秀的抗氧化性能.通过不同机理抗氧剂之间的协同,不仅可以获得优秀的抗氧化性能,还可获得附加的极压、抗磨和减摩性能,而且有的减摩、抗磨性能还非常突出,如烷基化二苯胺、氨基甲酸锌和有机钼酸酯组成的三元复合添加剂体系.     

1,3,5-三甲基-2,4,6-三(3,5-二叔丁基-4-羟基苄基)苯的常压合成新工艺

以2,6-二叔丁基苯酚、多聚甲醛和均三甲苯为原料,经两步常压反应合成了1,3,5-三甲基-2,4,6-三(3, 5-二叔丁基-4-羟基苄基)苯(即抗氧剂330)。通过正交设计,分别对两步合成反应的影响因素进行了考察,最优条件为:第一步,以甲醇为溶剂,n(2,6-二叔丁基苯酚):n(多聚甲醛)=1:1.6,反应时间为8 h,以二甲胺水(w=33%)溶液为催化剂,收率可达83.8%;第二步,以二氯甲烷为溶剂,n(均三甲苯):n(3,4-二叔丁基-4-羟基苄基甲基醚)=1:3.9,以H_2SO_4(w=80%)为催化剂,反应时间为1 h,收率可达90.4%。对产物进行了IR、元素分析、熔点及透光率测定,确定产物为目标产物。该工艺所得产物纯度高、成本低、三废少。