1-苯基-3-甲基-5-吡唑啉酮(PMP)柱前衍生化寡糖链的HPLC分离及其激光解吸电离质谱分析

以1-苯基-3-甲基-5-吡唑啉酮(PMP)为衍生化试剂对寡糖链进行标记, 用氨水替代氢氧化钠溶液作碱性介质, 衍生化反应后氨水可通过干燥除去, 省去了脱盐处理过程, 衍生化的寡糖可直接进行激光解吸电离质谱分析. 建立起了PMP衍生化寡糖的RP-HPLC分离分析模式, 在此HPLC分析条件下, 可以对标记的寡糖链进行样品分离及制备.     

以1,4-二甲基咔唑-9-丙酸为荧光衍生化试剂高效液相色谱法测定醇

1,4-二甲基咔唑-9-丙酸与间苯二磺酰氯反应生成混合酸酐,该混合酸酐能够衍生化18个碳以下的直链脂肪伯醇、6个碳以下的仲醇,以及叔丁醇和胆固醇;将荧光衍生物用反相C18液相色谱柱进行分离,在室温下10min完成衍生化反应,衍生物24h内基本稳定.基于此,建立了血清中醇的高效液相色谱测定方法.     

柱前衍生化法分离3-羟基丁酸乙酯光学异构体

采用三氟乙酸酐柱前衍生化在β-环糊精毛细管柱(CyclodexB)上分离3-羟基丁酸乙酯光学异构体.考察了衍生化反应条件对3-羟基丁酸乙酯衍生化反应的影响,柱温对3-羟基丁酸乙酯衍生物3-(2,2,2-三氟乙酰氧基)丁酸乙酯光学异构体分离的影响.通过光学异构体分离过程中的热力学参数的计算,探讨光学异构体分离过程的驱动力.实验结果表明,当三氟乙酸酐与3-羟基丁酸乙酯的摩尔比为5:1时,室温下反应5 min,3-羟基丁酸乙酯可定量转化成3-(2,2,2-三氟乙酰氧基)丁酸乙酯;在柱温为62℃时,3-(2,2,2-三氟乙酰氧基)丁酸乙酯光学异构体的分离因子(α)和分离度(R)分别为1.02和1.26.而且,3-(2,2,2-三氟乙酰氧基)丁酸乙酯光学异构体的拆分过程主要是一个焓驱动的过程,且β-环糊精表面与3-(2,2,2-三氟乙酰氧基)丁酸乙酯之间的相互作用在其分离过程中起了重要作用.     

2, 4, 6-三硝基苯酚衍生化β-环糊精键合

β-环糊精键合硅胶经对甲苯磺酰化后 , 与 2, 4, 6-三硝基苯酚 (PA)反应得到 2,4,6-三硝基苯酚衍生化β-环糊精键合硅胶固定相 ( PCDS) ; 采用元素分析、漫反射傅里叶变换红外光谱等方法对其进行了表征 ; 考察了 PCDS对稠环芳烃、位置异构体、丹磺酰化氨基酸等物质的分离性能 , 并对其分离机理进行了初步探讨 .     

8-羟基喹啉衍生化β-环糊精键合硅胶液相色谱固定相的合成与评价

β－环糊精键合硅胶经对甲苯磺酰化后, 与８－羟基喹啉反应得到８－羟基喹啉衍生化β－环糊精键合硅胶固定相（ＱＣＤＳ）． 采用元素分析、热分析及固体核磁波谱对键合固定相进行表征． 考察了ＱＣＤＳ对位置异构体、丹磺酰化氨基酸异构体、苯丙酸类药物和核苷等的分离性能．     

衍生化-液液萃取气相色谱法测定环境水体中苦味酸

建立衍生化-液液萃取气相色谱法测定环境水体中的苦味酸。环境水体中的苦味酸经次氯酸钠氯化衍生后,用正己烷提取后进行气相色谱分析。对萃取溶剂、衍生化反应温度和时间、衍生试剂(次氯酸钠)的加入量、色谱柱的选择以及色谱分析条件进行了优化,采取正己烷作为萃取试剂,加入次氯酸钠溶液2.0 mL,选择衍生化反应温度为35℃,反应时间为50 min,DB-5细管柱(30 m×0.32 mm,0.25μm)作为分离柱,当取样体积为10 mL时,方法检出限为0.2μg/L。用该方法对实验用水做了高、中、低质量浓度水平的加标回收试验,回收率为85.5%~105.6%,相对标准偏差为2.93%~4.49%(n=6)。     

1,8-二氨基萘衍生化气相色谱-质谱法测定血浆中亚硝酸盐含量

本文通过探索衍生化反应条件,提出1,8-二氨基萘衍生化气相色谱-质谱法测定血浆中亚硝酸盐含量的新方法。实验证实:该方法可直接在血浆中对NO-2进行衍生化,NO-2在0.05~20μg/mL浓度范围内线性关系良好(R2=0.9979);检测限为0.01μg/mL;回收率为87.63%~119.2%;实验耗时30min。与文献方法相比较,具有操作简便快捷、检测限低、回收率和精密度高的优点,在临床医学研究中具有实际应用价值。     

甘氨酸衍生化β-环糊精键合硅胶液相色谱固定相的合成与评价

 β-环糊精键合硅胶经对甲苯磺酰化后,与甘氨酸反应得到甘氨酸衍生化β-环糊精键合硅胶固定相(GCDS)。考察了GCDS对位置异构体、丹磺酰化氨基酸异构体、苯丙酸类药物等的分离性能,研究了流动相中甲醇浓度、pH以及柱温对色谱保留行为的影响。     

用GC-M S-SI M法测定酱油中的3-氯-1,2丙二醇

利用气相色谱 -质谱联用离子选择检测法 (GC -MS-SIM)测定酱油中3 -氯 -1,2 -丙二醇(3_CPD),样品用苯硼酸衍生化处理 ,正己烷抽提 ,用HP-112m×0.2mm毛细管色谱柱分离 ,选择基峰离子m/z147进行测定 ,检出限0.001×10-6。该法操作简单 ,快捷 ,灵敏度高。     

新型靛红衍生化β-环糊精键合SBA-15液相色谱固定相的制备与表征

利用靛红的羰基与β-环糊精单取代乙二胺的缩合反应,合成得到种靛红衍生化β-环糊精Schiff碱类化合物。以3-异氰酸丙基三乙氧基硅烷为偶联剂,将其键合到自制的有序介孔二氧化硅材料SBA-15表面,制得种新型的靛红衍生化β-环糊精键合SBA-15液相色谱固定相(ISCDP)。分别对β-环糊精衍生物、SBA-15及固定相进行必要的结构表征。在反相色谱条件下,以卤代尿嘧啶类极性化合物和二取代苯位置异构体为探针,评价新固定相的基本色谱性能。在极性有机溶剂和反相模式下,将新固定相分别用于β-受体阻滞剂药物和丹磺酰化氨基酸对映体的拆分,探讨了相关色谱分离机理。实验表明,靛红吲哚环的引入,增强了环糊精类固定相对卤代尿嘧啶的反相色谱分离能力,分析时间小于7 min。固定相分离硝基苯胺、氨基苯酚和苯二酚的位置异构体时也表现出较高的立体选择性,其中对位异构体均后被洗脱,这与包结作用相关;靛红衍生化β-环糊精配体也提高了固定相的手性分离能力,除疏水作用外,靛红衍生化β-环糊精配体还能提供偶极、氢键、π-π和包结等作用,多种协同作用力有利于提高新固定相的手性和非手性分离的选择性。SBA-15作为键合基质,其有序的孔结构有利于保持色谱柱的良好渗透性和小的传质阻力,在快速高效分离分析中具有应用潜能。     

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.