UPLC-MS/MS法测定中药材中齐墩果酸与熊果酸的含量

建立了一种同时检测中药材中齐墩果酸(OA)和熊果酸(UA)含量的超高效液相色谱串联质谱方法。采用超高效液相色谱-三级四极杆质谱(UPLC-TQMS)法对样品进行测定,Waters Acquity UPLC BEH C_(18)色谱柱(50 mm×2.1 mm,1.7μm)进行分离,以乙腈-5 mmol/L乙酸铵水溶液(氨水调至pH 9.24)为流动相,梯度洗脱;负离子模式下检测。结果表明,齐墩果酸和熊果酸在0.5~50.0 ng/mL浓度范围内线性关系良好,相关系数(r~2)分别为0.999 8和0.999 7;检出限(S/N=3)分别为0.006 6,0.012 8 ng/mL,定量下限(S/N=10)分别为0.002 0,0.003 8 ng/mL;对OA和UA进行加标回收实验,平均回收率分别为101.1%和100.8%,相对标准偏差(RSD,n=9)分别为1.8%和0.04%。对10种不同中药材中齐墩果酸和熊果酸含量进行检测,结果表明该方法快速简便、准确度高、重现性好,可用于含有齐墩果酸和熊果酸的中药材含量测定。     

高效液相色谱串联质谱法测定动物源性食品中苯佐卡因、利多卡因

建立高效液相色谱串联质谱法检测动物源性食品中的苯佐卡因、利多卡因残留量的分析方法。称取粉碎后的样品5.0 g，置于50 mL离心管中，加入1 g NaCl,10 mL乙腈，振荡提取20 min后，以4 500 r/min转速离心5 min，取上清液6 mL，分别加入乙二胺-N-丙基硅烷(pPSA) 50 mg、C₁₈ 50 mg，然后在涡旋仪上涡旋1 min，以4 500 r/min转速离心5 min，然后取0.5 mL上清液与0.5 mL复溶液[0.1%甲酸-乙腈(体积比为80∶20)混合液]混合，过0.22μm滤膜，供高效液相色谱串联质谱法测定。以0.1%乙酸-乙腈为流动相，C₁₈柱为色谱柱，多反应监测模式分析，色谱峰面积外标法定量。苯佐卡因和利多卡因在0.1～50.0μg/L的质量浓度范围内线性关系良好，相关系数均大于0.999，检出限分别为0.2、0.1μg/kg，定量限分别为0.7、0.5μg/kg，回收率分别为85.0%～100.6%、87.7%～99.8%,5次测定结果的相对标准偏差分别为0.3%～3.5%、1.8%～3.6%。...     

同位素稀释超高效液相色谱-串联质谱法测定人血清中孕酮

建立了超高效液相色谱-串联质谱(UPLC-MS/MS)测定人血清中孕酮的分析方法。血清样品经乙酸乙酯、正己烷液液萃取(LLE)后,采用Acquity UPLC BEH C_(18)色谱柱(2.1 mm×100 mm,1.7μm)进行梯度分离,色谱运行时间为5 min,采用电喷雾(ESI)正离子电离模式和多反应监测(MRM)扫描模式,同位素内标法定量。考察了两步萃取法对孕酮的提取效果,不同流动相的分离效果以及样品稳定性,结果表明以甲醇-0.1%氨水溶液为流动相时分离效果较好。优化条件下,孕酮在10～10 000pg/mL范围内线性关系良好(r~2=0.999 8),方法检出限和定量下限分别为5、10 pg/mL;平均加标回收率为91.5%～106%,日内相对标准偏差(RSD)为1.2%～8.2%,日间RSD为4.1%～9.1%。采用该方法对30个真实血清样品进行测定,孕酮质量浓度为0.050 2～1.363 5 ng/mL,均在正常生理范围内。该方法灵敏度高、准确可靠,可用于临床血清样品中孕酮生理水平的检测。     

甲卡西酮的LC-MS/MS定性定量分析方法

建立了LC-MS/MS法定性定量分析甲卡西酮。采用三重串联四极杆液质联用仪(LC/QQQ),AgilentZorbax Eclipse Plus C18色谱柱(100 mm×2.1 mm,1.8μm),流动相为0.1%甲酸-乙腈,梯度洗脱,流速为0.3mL/min。质谱应用ESI源、正离子模式、多反应监测(MRM)方式。在0.1～10 000 ng/mL质量浓度范围内线性关系良好,r2=0.999 8,日内与日间保留时间和峰面积的相对标准偏差不大于5.28%,检出限为0.04 ng/mL,回收率为95.6%～100.7%。该方法适用于甲卡西酮的定性、定量分析。     

固相萃取净化/超高效液相色谱-串联质谱法测定养殖环境中地西泮及其代谢物

建立了固相萃取净化/超高效液相色谱-串联质谱(SPE/UPLC-MS/MS)同时测定养殖水和沉积物样品中地西泮及其3种代谢物的分析方法。水样经0.45μm玻璃纤维膜过滤,沉积物采用1%氨水-乙酸乙酯提取后,均通过混合型阳离子交换固相萃取(MCX SPE)柱富集净化。目标物用5%氨水-乙腈溶液洗脱后吹干,1 mL 40%乙腈水溶液溶解残渣,UPLC-MS/MS测定。经Phenomenex Kinetex C₁₈(100 mm×2.1 mm,1.7μm)色谱柱分离,乙腈和0.1%甲酸水溶液为流动相进行梯度洗脱。采用电喷雾正离子电离,多反应监测(MRM)模式下测定,内标法定量。4种目标物在0.1～100μg/L范围内的线性关系良好,相关系数(r²)大于0.999。水体和沉积物中的方法检出限分别为1.0～2.0 ng/L和0.02～0.05μg/kg,定量下限分别为2.0～5.0 ng/L和0.05～0.1μg/kg;平均加标回收率为90.2%～115%,相对标准偏差(RSD,n=6)为2.1%～9.6%。该方法灵敏度高,实用性强,可满足养殖环境中地...     

液相色谱-串联质谱法测定白芷中3种香豆素

建立了白芷中欧前胡素,异欧前胡素和氧化前胡素的液相色谱-串联质谱分析法。白芷提取液经Waters XTerra-C18(150mm×3.9 mm,5μm)色谱柱分离,以1mmol/L乙酸铵溶液和乙腈为流动相进行洗脱,以电喷雾正离子(ESI+)模式电离,多反应监测(MRM)模式检测,外标法定量。欧前胡素,异欧前胡素和氧化前胡素分别在0.05～10μg/mL,0.05～13μg/mL和0.1～120μg/mL范围内呈线性相关,相关系数(r)分别为0.9993,0.9991和0.9994,检出限分别为30,30和50 ng/mL,平均加标回收率为100.1%,99.4%和98.4%,相对标准偏差分别为2.2%,2.6%和2.8%(ρ=0.5μg/mL,n=6),该法可以满足同时检测白芷中欧前胡素,异欧前胡素和氧化前胡素的需求。     

QuEChERS结合超高效液相色谱-串联质谱法检验腐败血中4-甲基甲卡西酮和甲卡西酮

建立了腐败血中4-甲基甲卡西酮和甲卡西酮的超高效液相色谱-三重四级杆串联质谱(UPLC-MS/MS)检测方法。腐败血样品经乙腈水混合溶液(乙腈:水=4:1,V/V)提取,无水MgSO_4脱水和C_(18)吸附剂净化。选用Waters BEH C_(18)色谱柱分离,0.1%甲酸-水(5 mmol/L乙酸铵)和乙腈作为流动相进行梯度洗脱,电喷雾电离,正离子(ESI~+)模式扫描,多反应监测(MRM)模式检测。4-甲基甲卡西酮和甲卡西酮在0.5～100 ng/mL范围内线性关系良好(R~2≧0.9993),检出限(S/N=3)分别为0.01 ng/mL(4-甲基甲卡西酮)和0.03 ng/mL(甲卡西酮),定量限(S/N=10)分别为0.1 ng/mL(4-甲基甲卡西酮)和0.5 ng/mL(甲卡西酮)。     

高效液相色谱-串联质谱法同时测定盐酸拉贝洛尔中三种杂质

建立高效液相色谱-串联质谱法同时测定盐酸拉贝洛尔中2-羟基-5-[1-羟基-2-[(1-甲基-3-苯丙基)氨基]乙基]苯甲酸、2-羟基-5-[1-羟基-2-[(1-甲基-3-苯丙基)氨基]乙基]苯甲酸甲酯和2-羟基-5-(2-(4-苯基丁-2-氨基)乙酰)苯甲酰胺的含量。采用Agilent Eclipse XDB-C18柱（250 mm×4.6 mm,5μm）为分离柱,以0.1%（质量分数）的乙酸溶液为流动相A,乙腈-0.1%的乙酸溶液（体积比为1∶1）为流动相B,流量为1.5 mL/min,梯度洗脱,柱温为40℃,进样体积为10μL,离子源为大气压化学电离源,采用多反应监测模式。三种杂质的质量浓度分别在1.0160～203.20、1.0320～206.40、1.0370～207.40 ng/mL范围内与色谱峰面积线性相关,相关系数均大于0.999,3种化合物的检出限均为0.03ng/mL,定量限均为0.10 ng/mL。样品平均回收率分别为95.3%、92.4%、91.9%,测定结果的相对标准偏差分别为1.44%、1.46%、1.11%(n=9)。该方法可用于同时测定盐酸拉贝洛尔中3...     

同位素稀释高效液相色谱-串联质谱法测定水体、底泥、鱼及虾中氯硝柳胺残留量

建立了水体、底泥、鱼体自然比例带皮肌肉和虾肌肉中氯硝柳胺(NIC)残留量测定的同位素稀释高效液相色谱-串联质谱(HPLC-MS/MS)法。水样经碱化后以乙酸乙酯提取,其他样品采用0.1%氨水乙腈提取,C_(18)粉进行样品净化。以乙腈-水为流动相,流速为0.3 mL/min,采用Thermo Hypersil Gold C_(18)(150 mm×2.1 mm,5μm)色谱柱进行分离,氯硝柳胺稳定同位素标记物(氯硝柳胺-~(13)C_6)为内标,选择反应监测(SRM)模式扫描,内标法定量。结果表明氯硝柳胺在0.2～200μg/L范围内呈良好线性关系,相关系数(r~2)不小于0.999 5。空白水样在2.5、25、250 ng/L加标水平下的平均回收率为90.5%～109%,相对标准偏差(RSD)为3.2%～11%,检出限(LOD)为1.0 ng/L,定量下限(LOQ)为2.5 ng/L;空白底泥、黄颡鱼自然比例带皮肌肉和克氏原螯虾肌肉在0.5、5.0、50μg/kg加标水平下的平均回收率分别为89.4%～113%、92.8%～110%和94.1%～107%,RSD分别为4.6%～12%、2.8%～11%和3.2%～9.3%,LOD均为0.2μg/kg,LOQ均为0.5μg/kg。该方法的灵敏度、准确度和选择性高,适用于实际水产养殖环境水体、底泥、鱼和虾中氯硝柳胺的残留分析。     

基质分散固相萃取-高效液相色谱/串联质谱法检测红薯中氯吡脲

建立了分散固相萃取-高效液相色谱/串联质谱法测定红薯中氯吡脲含量的分析方法.样品经分散剂(硅胶,C18HC)研磨分散提取,甲醇洗脱.采用Thermo Hypersil Gold C18色谱柱(150×2,1 mm,5μm)分离,以甲醇(A)/0.1％甲酸-5 mmol/L甲酸铵(B)作为流动相,梯度洗脱,采用串联质谱在正离子扫描方式下,通过选择反应模式定量分析,外标法定量.氯吡脲在2.63～675.00 ng/mL范围内线性关系良好,相关系数R2＞0.999.定量检测限为0.66 ng/mL.氯吡脲在10、25、50 ng/g三个浓度水平的添加回收率在70％～130％之间.该方法操作简单、准确,适用于红薯中氯吡脲的定量检测.     

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.