ASE-HPLC法测定黄姜中薯蓣皂甙元的含量

采用ASE200快速溶剂萃取机提取技术和高效液相色谱法,测定黄姜中薯蓣皂甙元的含量。确定了ASE200提取条件以及HPLC测定条件,以甲醇作为流动相,流速1mL/min,UV检测器,测定波长210nm,采用YWGC18柱(150mm×4.6mmi.d.,10μm)。测定皂甙元的线性范围为0.01～2.93g/L,r=0.9996,样品检出限为0.2mg/L,加标回收率为97.1%～99.8%,RSD=1.1%(n=7)。     

间接原子吸收法测定黄姜中的薯蓣皂甙元

提出了间接测定黄姜中薯蓣皂甙元的原子吸收光谱法。该法基于薯蓣皂甙元能与碱式醋酸铅发生络合反应,生成难溶于水的白色沉淀,经离心分离后,用原子吸收法测定上清液中过量的铅离子,可间接测定薯蓣皂甙元的含量。该法线性范围为0.0~40.0 mg/L;相对标准偏差(relative standard deviation,RSD)为0.9%~1.1%;回收率为98.9%~102.9%。     

固相萃取-高效液相色谱检测葡萄酒中赭曲霉毒素A

使用C18小柱固相萃取, C18反相柱(250 mm×4.6 mm i.d.)分离,V(乙腈):V(水):V(乙酸)＝99:99:2为流动相,荧光检测器(激发波长333 nm,发射波长460 nm)检测,测定葡萄酒中赭曲霉毒素A.其质量浓度在6.25～200 ng/mL范围内呈良好线性,相关系数为0.9997.样品经浓缩60倍后,方法检出限为0.027 ng/mL.对红葡萄酒、干红及白葡萄酒进行了加标回收实验,回收率为80.1%～109.8%.平行7份样品加标回收率相对标准偏差为5.9%.对市售6种葡萄酒进行了赭曲霉毒素A的测定.     

黄姜中薯蓣皂苷元的薄层扫描法测定

采用瑞士CAMAG Scanner 3薄层扫描仪对黄姜中的薯蓣皂苷元进行测定,以V(石油醚)∶V(氯仿)∶V(甲醇)=10∶10∶0.5为展开剂,用20 g/L磷钼酸无水乙醇溶液喷雾显色,140℃烘烤约5 min,检测波长650 nm,狭缝尺寸为6.00 mm×0.30 mm。结果表明:薯蓣皂苷元在0.3~1.8μg的范围内与峰面积呈良好线性关系,相关系数r=0.9983,回收率为96.94%(n=5)。     

HPLC法测定盐酸美他环素片的含量

建立用外标法测定盐酸美他环素片含量的简单高效液相色谱方法.采用PurospherStar C18色谱柱(250mm×4.6mm,5μgm);流动相为:V(甲醇):V(水)=50:50混合后用H3PO4调节pH至3.0±0.02;检测波长:280nm;进样量:20μL,流量:0.7 mL/min;温度35℃.美他环素在20.02～200.2μg/mL浓度范围内线性关系良好(r=0.99999);平均回收率为98.6%,回收率的RSD为0.6%.本方法可用于盐酸美他环素片的含量测定.     

分光光度法测定薯蓣皂苷元

采用高氯酸反应使薯蓣皂苷元显色 ,对影响显色反应的主要因素进行了考察 ,于 41 0nm波长处对穿山龙中薯蓣皂苷元的含量进行测定 ,测定结果与高效液相色谱法相近。方法的线性范围为 3.1 2～2 1 .84μg mL ,适用于薯蓣皂苷元提取过程中的常规检测     

多功能柱净化-高效液相色谱法检测麦类中赭曲霉毒素A

本文提出了一种采用高效液相色谱/荧光检测法(HPLC/FLD)测定麦类样品中赭曲霉毒素A的方法.样品经V(乙腈):V(水)=84:16提取,多功能柱净化,C18色谱柱(4.6×250 mm,5μm)分离,V(水):V(乙腈):V(乙酸)=102:96:2作流动相,流速1.0 mL/min.结果表明,标准工作液在浓度1.0～50.0μg/L范围内,峰面积与浓度成良好的线性关系,线性相关系数＞0.9999,样品在3.0,10.0,50.0 ng/g添加水平的回收率为60%～85%,相对标准偏差为7.9%～8.8%(n=8),方法检出限为3.0 ng/g(S/N＞10).本法快速、准确、操作简单,可满足大批麦类样品的检测需要.     

高效液相色谱法测定叔丁基对苯二酚的含量

建立了HPLC测定叔丁基对苯二酚含量的方法:色谱柱:Shim-pack VpODS(150 mmt×4.6 mm,5μm)接C18保护柱(20 mm×4.6 mm,5μm);以V(乙腈):V(水)=32:68(含1%乙酸)作为流动相;流速:0.8 mL/min;检测波长:290 mm;柱温:25℃.结果表明TBHQ质量浓度在2×10-4～1.0 mg/mL范围内与峰面积线性关系良好r≥0.9999,最低检测限为4 ng,并建立了回收率及日内和日见精密度实验.     

固相萃取RP-HPLC测定小鼠肝脏组织中的多沙唑嗪

研究建立了小鼠肝脏组织中多沙唑嗪的反相高效液相色谱测定方法. 肝组织样品经过匀浆、提取、C18固相萃取小柱富集净化后, 在YMC C18色谱柱(4.6 mm i.d.×250 mm, 5 μm)上, 以V(甲醇)∶V(0.02 mol/L KH2PO4) ＝70∶30, pH 3.0为流动相, 流速0.6 mL/min, 检测波长246 nm对多沙唑嗪进行测定. 结果表明, 肝脏组织中的多沙唑嗪在0.5～10 μg/mL范围内与峰面积呈良好线性关系. 平均回收率为91.0%, RSD为3.3%. 检出限为1 ng. 方法操作简便, 重现性好, 适用于肝脏组织中多沙唑嗪药物的浓度测定及代谢研究.     

高效液相色谱法测定人血浆及尿液中头孢呋辛和舒巴坦

建立反相HPLC-UV法同时测定人血浆及尿中头孢呋辛(CXM)和舒巴坦(SUL)的方法.采用Welch Materials XB-C18分析柱(150 mm×4.6 mm,5 μm ) ,流动相为乙腈-0.01 mol/L KH2PO4 (血浆测定15∶ 85(V/V),尿样测定10∶ 90(V/V),含0.04%三乙胺,以H3PO4调节至pH 3.2),流速1.0 mL/min,紫外检测波长SUL为220 nm、CXM及内标咖啡酸为274 nm.血浆样品在酸性条件下用乙醚提取浓集后进样,以内标法进行定量分析.尿样稀释后直接进样,以外标法进行定量分析.血浆测定中SUL和CXM浓度分别在0.25～200 mg/L和0.5～400 mg/L范围内线性良好; 萃取回收率分别为75.6%～88.1%和68.6%～77.4%; 批内与批间RSD均小于9%,方法回收率分别为94.6%～113.6%和91.9%～101.8%.尿样中SUL和CXM浓度分别在5～5120 mg/L和10～10240 mg/L范围内线性良好; 批内与批间RSD均小于3%; 方法回收率分别为92.9%～111.1%和98.0%～105.3%.本方法快速简便, 灵敏准确,可用于同时测定血浆及尿中SUL和CXM浓度,亦可用于药代动力学、生物利用度研究.     

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.