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。     

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%。     

浊点萃取-高效液相色谱法同时测定人尿中的4种抗凝血鼠药

建立了基于浊点萃取同时测定人尿中杀鼠灵、杀鼠醚、溴敌隆和溴鼠灵的反相高效液相色谱法。以非离子表面活性剂TritonX-114为萃取剂,考察了色谱测定条件,优化了浊点萃取参数。5mL尿样中加入0.030gNaCl,30μL甲酸和5%(w/v)TritonX-114400μL,50℃萃取15min,4种目标物的萃取效率能达到85%以上。在选择的色谱条件下,以V(甲醇)∶V(1%甲酸)=90∶10为流动相,待测组分经反相C18色谱柱分离,于306nm波长处用二极管阵列检测器检测,10min可完成分析。4种鼠药中杀鼠醚在0.01～5.0mg/L,其余3种在0.02～5.0mg/L范围内呈良好的线性关系(r≥0.997);尿样的标准加入回收率为71.2%～114.5%;相对标准偏差小于7.0%。对于5mL尿液,富集相用50μL甲醇稀释,萃取浓缩因子可达到28倍。定量检出浓度分别为:杀鼠灵0.016mg/L,杀鼠醚0.001mg/L,溴敌隆0.005mg/L,溴鼠灵0.003mg/L。本法简便快速、灵敏可靠、绿色环保,能满足鼠药中毒应急检测的要求。     

超高效液相色谱串联质谱法测定4种抗凝血灭鼠剂在水环境突发性污染事故中的痕量残留

1 引言 杀鼠灵、杀鼠醚、溴敌隆、溴鼠灵等抗凝血灭鼠剂是目前最常用的缓效灭鼠剂,当大量灭鼠剂不慎污染水源引起突发性污染事故会严重影响居民正常饮水,甚至引发水性疾病的暴发流行或污染物中毒,快捷准确地提供分析数据是有效处理突发性环境事件必要的前提条件.     

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。     

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.     

自动索氏提取-固相萃取-气相色谱-串联质谱法测定土壤环境中5种杀螨剂的残留量北大核心CSCD

称取5 g预处理好的土壤样品至索氏提取器中,以二氯甲烷为提取溶剂进行提取。提取液经HLB固相萃取小柱净化,甲醇洗脱,收集所有洗脱液,氮吹至近干,最后用甲醇定容至1 mL,于气相色谱-三重四极杆串联质谱仪中以多反应监测模式进行分析,外标法定量。结果显示:杀螨醚、虫螨畏、灭螨猛、杀螨酯和乙酯杀螨醇标准曲线的线性范围均为0.01~5.0 mg·L^(-1),检出限(3S/N)依次为0.004,0.006,0.008,0.010,0.008 mg·kg^(-1);在3个不同加标浓度水平下,空白土壤样品中5种杀螨剂的回收率为84.8%~99.6%,测定值的相对标准偏差(n=6)为2.1%~4.0%;方法用于5份实际土壤样品分析,其中杀螨醚、灭螨猛、杀螨酯和乙酯杀螨醇被检出,检出量为0.003~0.007 mg·kg^(-1)。     

番红花化学成分研究 III. 番红花花粉中的番红花新苷甲和乙的结构

从番红花(crocus sativus L.)花粉中分到两个新苷, 命名为番红花新苷甲(1)和乙(2)。经理化性质和对它们的IR、UV、^1HNMR和MS数据的分析, 鉴定1为异鼠李素-4'-O-α-L-鼠李吡喃(1→2)β-D-葡萄吡喃糖苷, 2为β-对羟基苯基-乙醇-α-O-α-L-鼠李吡喃糖(1→2)-β-D-葡萄吡喃糖苷。     

番红花化学成分研究 III. 番红花花粉中的番红花新苷甲和乙的结构

从番红花(crocus sativus L.)花粉中分到两个新苷, 命名为番红花新苷甲(1)和乙(2)。经理化性质和对它们的IR、UV、^1HNMR和MS数据的分析, 鉴定1为异鼠李素-4'-O-α-L-鼠李吡喃(1→2)β-D-葡萄吡喃糖苷, 2为β-对羟基苯基-乙醇-α-O-α-L-鼠李吡喃糖(1→2)-β-D-葡萄吡喃糖苷。     

反相离子对高效液相色谱法测定母粉及母液中的杀鼠新

用反相离子对高效液相色谱法测定了杀鼠新母粉及母液中有效成份含量。采用Partisil-10ODS色谱柱，以甲醇：离子对溶液＝80：20（体积比）为流动相，离子对溶液为0.005mol/L四丁基铵磷酸盐（pH为7.5)的缓冲溶液，测定波长285nm。方法在0.025-0.15g/L范围内有很好的线性关系。杀鼠新母粉和母液的相对标准偏差分别为1.24%、0.77%(n=7)，回收率分别为：母粉,97.7%-99.8%；母液，98.5%-100.4%。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.