高效液相色谱法测定土壤中香豆素类灭鼠药残留

建立了测定土壤中杀鼠灵、杀鼠醚、溴敌隆、氟鼠灵、溴鼠隆5种香豆素类灭鼠药残留量的柱后衍生荧光检测高效液相色谱方法。样品在加入内标物氯杀鼠灵后用丙酮-氨水-甲醇（体积比为100：3：100）混合液提取,浓缩的提取液用5 mL正己烷-氯仿（体积比为3：1）混合液溶解,NH₂固相萃取小柱净化,用15 mL 50 mmol/L四丁基磷酸二氢铵甲醇溶液洗脱分析物,移除溶剂,用甲醇-0.25%（体积分数）乙酸水溶液（体积比为3：2）混合液溶解,过滤后,经高效液相色谱分离,以甲醇-氨水-水（体积比为1：1：8）混合液为衍生试剂进行柱后衍生,采用荧光检测器检测。杀鼠灵、杀鼠醚、溴敌隆、氟鼠灵、溴鼠隆5种鼠药在0.02～10.00 mg/L范围内线性关系良好,相关系数均大于0.999,定量限（LOQ,S/N=10）为2.2～18.5 μg/L。在0.1～0.3 mg/kg添加水平内,5种灭鼠药的回收率为94.6%～118.0%,相对标准偏差（RSD）为0.8%～10.2% （n=3）。实验结果表明该方法灵敏、准确,重复性好。     

反相高效液相色谱法同时检测食物中毒样品中的敌鼠钠盐、杀鼠醚和杀鼠灵

建立了反相高效液相色谱-二极管阵列检测器同时快速检测食物中毒样品中的敌鼠钠盐、杀鼠醚和杀鼠灵的分析方法。固体样品用乙腈提取,液体样品用乙酸乙酯提取。以V(乙腈)∶V(0.010 mol/L乙酸铵)=57∶43(pH 4.50)为流动相,经C18色谱柱分离,二极管阵列检测器分别在波长286和306 nm处同时检测,在8 min内即可完成色谱分析。敌鼠钠盐、杀鼠醚和杀鼠灵在0.05~20.0μg/mL范围内与其色谱峰面积呈良好的线性关系,方法的检出限固体样品为0.015μg/g,液体样品为0.003μg/mL,样品加标平均回收率在85.0%~109.2%之间,相对标准偏差为1.0%~9.6%。     

高效液相色谱-荧光检测法同时测定全血中5种香豆素类杀鼠剂

建立了同时测定全血中杀鼠灵、杀鼠迷、溴敌隆、氟鼠灵与溴鼠灵等5种香豆素类杀鼠剂的简便、灵敏、准确的高效液相色谱-变波长荧光分析方法。全血样品经乙酸乙酯提取后,在XDB C18柱(150 mm×2.1 mm, 5 μm)上以甲醇-0.2%乙酸水溶液(体积比为88∶12)混合液为流动相,采用荧光变波长程序检测,同时通过建立各杀鼠剂的荧光光谱库,利用谱库检索,提高定性的准确度。各杀鼠剂的线性范围为0.01~10.00 mg/L（杀鼠灵为0.05~10.00 mg/L）,检出限为0.01~0.05 mg/L,方法的加标回收率为81%～98%,其相对标准偏差（RSD）为3.8%～8.5%。该法适用于中毒病人的中毒诊断检测。     

蔬菜、水果中4种抗凝血灭鼠剂残留的高效液相色谱-串联质谱法测定

建立了蔬菜及水果中溴鼠灵、溴敌隆、敌鼠、杀鼠酮灭鼠剂同时检测的高效液相色谱-质谱/质谱(HPLC-MS/MS)分析方法,前处理采用乙腈提取、碱性氧化铝小柱净化.结果表明,4种灭鼠剂线性范围为2.0 ～50 μg/L,r均大于0.997 5;溴鼠灵和溴敌隆的检出限可达0.5 μg/kg,回收率分别为77% ～96%,69% ～113%;敌鼠和杀鼠酮的检出限为1.0 μg/kg,回收率分别为72% ～94%,71% ～90%;RSDs均小于10%,可以满足目前国际限量要求.     

分散液-液微萃取-气相色谱-质谱法同时测定中毒样品中有毒生物碱和鼠药

建立了分散液-液微萃取(Dispersive liquid-liquid micro-extraction,DLLME)与气相色谱-质谱(GCMS)联用同时测定中毒样品中3种鼠药(毒鼠强、溴鼠灵、溴敌隆)和5种有毒生物碱(莨菪碱、东莨菪碱碱、钩吻碱、士的宁、马钱子碱)的方法。100μL萃取剂氯仿与600μL分散剂甲醇混合后,迅速注入样品,萃取过程在乳化体系中完成;以8000 r/min离心5 min,使两相分层,取下层有机相进行GC-MS分析。考察了萃取剂、分散剂的种类和体积、萃取时间、pH值及盐浓度对萃取效率的影响。在优化条件下,各目标物在水样、尿样、黄酒样的检出限为0.003~1.0μg/L,在米饭样品检出限为0.002~0.2μg/kg;各目标物低、中、高加标回收率为81.0%~110%,精密度均小于7%。本方法灵敏度高,快捷高效,适用于中毒样品中有毒生物碱和鼠药的同时测定。     

离子液体[C_4 mim][PF_6]超声辅助萃取/LC-MS/MS法测定水中痕量溴敌隆及溴鼠灵

建立了离子液体超声辅助萃取/高效液相色谱-串联质谱联用测定水中溴敌隆和溴鼠灵的方法。采用疏水性离子液体1-丁基-3-甲基咪唑六氟磷酸盐[C4mim][PF6]萃取样品,考察了试样体积、pH值、温度、超声萃取时间和无机盐含量等因素对萃取效率的影响。待测物在XDB C18(150 mm×2.1 mm,5μm)色谱柱上,以甲醇-0.2%乙酸(85∶15)为流动相,电喷雾(ESI)电离负离子多反应监测模式(MRM)进行测定。在优化萃取条件下,溴敌隆和溴鼠灵在0.005~1.0μg·L-1范围内具有良好线性,相关系数(r)大于0.999,回收率为91.0%~97.8%,日内相对标准偏差为1.1%~6.6%,日间相对标准偏差为2.5%~9.1%,定量下限为0.005μg·L-1。建立的方法简便、干扰少、特异性强,可用于环境水样中痕量溴敌隆和溴鼠灵的测定。     

混合萃取剂-悬浮固化分散液相微萃取测定尿中的苯巯基尿酸

建立了混合萃取剂-悬浮固化分散液相微萃取联合高效液相色谱测定尿中苯巯基尿酸(S-phenylmer-capturic acid,SPMA)的方法。优化了微萃取的实验条件,取20 mL尿样并调节至pH 2.0,加入7.2 g固体NaCl,并振荡溶解;以100μL十二醇-三氯甲烷(1.8∶1,V/V)混合溶剂作为萃取剂,100μL甲醇作为分散剂,振摇使萃取剂分散于样液中;离心使萃取剂悬浮于样品溶液表面,"20℃冷冻至有机相凝固,转移凝固的萃取剂至EP管,室温下融化,离心后取上清液进样分析。苯巯基尿酸在0.025～1.25 mg/L浓度范围内线性良好,方法检出限为0.019 mg/L,日内精密度与日间精密度分别为2.2%～5.4%和2.5%～6.1%,将方法用于实际尿样的分析,取得了较满意的结果,加标回收率在86.8%～99.9%之间。本方法简便快捷、适合尿样批量分析。     

基于新型硼酸固相萃取柱的多巴胺色谱分析方法

用"点击化学"方法,将炔基化3-氨基苯硼酸与叠氮化硅胶反应,制备了新型硼酸固相萃取吸附剂。采用固相萃取(SPE)对样品进行前处理,反相高效液相色谱分离,紫外检测,建立了一种快速、高效、灵敏的多巴胺分析方法。固相萃取的最优条件为:对200 mg吸附剂装填的萃取柱,用甲醇活化,磷酸盐缓冲溶液(pH 8.0)平衡,再分别用1 mL水和2 mL 20%甲醇淋洗,3 mL 1 mol/L醋酸甲醇溶液洗脱。采用C18反相色谱柱,50 mmol/L磷酸二氢钠-乙腈-甲醇流动相(7∶2∶1,V/V)和检测波长280 nm的色谱条件,对洗脱液进行色谱分析。结果表明,该吸附剂对顺式邻羟基化合物有良好的识别能力。在最优萃取条件下,多巴胺的回收率达90%以上。多巴胺分析的线性范围为0.1～100 mg/L,检出限为0.0001 mg/L,相对标准偏差(RSD)<10.6%。在实际样品分析中,大鼠空白血加标液的回收率均高于97%,相对标准偏差为4.30%。     

加速溶剂萃取快速洗脱印迹聚合物中的模板分子

通过优化实验条件,选择洗脱温度80℃、加热时间5min、萃取压力10.4MPa、洗脱溶剂为300mL的甲醇/乙酸(90∶10,V/V),静态萃取时间8min、吹扫时间100s,对1.000g尼古丁印迹聚合物中的模板分子进行连续6次的萃取洗脱,洗脱效率达94.2%,模板渗漏量仅为9.8μg/L,萃取时间<70min。将2000mg洗脱后的印迹聚合物颗粒装填于3mL的聚丙烯固相萃取小柱中,用10mL甲醇/乙酸(90∶1,V/V)淋洗小柱,用高效液相色谱检测淋洗液中的尼古丁,获得模板的渗漏量为9.8μg/L。     

固相萃取-液相色谱-串联质谱法检测小鼠肌肉组织中矮壮素

建立了快速检测小鼠肌肉组织中矮壮素的固相萃取-液相色谱-串联质谱(SPE-LC-MS/MS)方法。小鼠肌肉样品经乙腈提取,弱阳离子交换(WCX)固相萃取柱净化,3 mL甲酸-甲醇(1∶99,V/V)重力洗脱。采用亲水作用色谱柱(HILIC),含10 mmol/L乙酸铵、0.1%甲酸水溶液-乙腈(40∶60,V/V)为流动相,以电喷雾正离子(ESI+)、多反应监测模式(MRM)进行矮壮素的定性分析,采用基质标准曲线外标法进行定量分析。结果表明:矮壮素的线性范围为5.0～500.0μg/L,线性相关系数为0.9991。在10.0,100.0和200.0μg/kg添加浓度下的回收率为73.2%～82.3%;相对标准偏差小于9.3%;方法定量限为10.0μg/kg,能够满足小鼠肌肉组织中痕量矮壮素检测的要求。     

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.