反相高效液相色谱法测定小鼠血浆及组织中的阿昔洛韦浓度

 建立了测定小鼠血浆、肝、肾、脾、肺等组织中阿昔洛韦 (ACV)浓度的高效液相色谱法。色谱柱为HypersilODS ,流动相为甲醇 水 冰醋酸 (体积比为 1∶99∶0 5 )混合溶液 ,流速为 1 5mL/min ,检测波长为 2 5 2nm。ACV血浆最低检测浓度为 2 0 μg/L ,各组织最低检测浓度为 5 0ng/g。血浆及组织匀浆中的ACV浓度在 0 1mg/L～ 4mg/L及 0 1μg/g～ 4μg/ g时线性关系良好 (r >0 99)。血浆及肝匀浆中的ACV回收率分别为 97 5 %～ 10 0 0 %和 10 0 0 %～ 10 6 0 % (n =5 )。该法精密度高 ,方便 ,快捷 。     

柱切换-荧光检测反相高效液相色谱法测定血浆中特布他林浓度

采用柱切换技术 荧光检测反相高效液相色谱法测定血浆中特布他林 (TB)浓度。使用LunaC8( 2 )和KromasilC18为分析柱 ( 1 5 0mm× 4.6mm ,5 μm)和预处理柱 ( 2 5mm× 4.6mm ,5 μm) ,流动相分别为pH 3 0 ,0 .0 3 3mol/L磷酸盐缓冲液∶甲醇∶乙腈 ( 92∶7∶1 )和水∶甲醇∶乙腈 ( 97∶2∶1 ) ,流速均为 1 .0ml/L。血浆样品经乙腈沉淀蛋白后进样 ,切换时间为 3 .2～ 4.2min。荧光检测 ,λex为 2 80nm ,λem为 3 0 9nm。以沙丁胺醇作内标 ,按内标法定量。标准曲线线性范围为 0 .8～ 3 2 μg/L ;最低定量限为 0 .8μg/L;TB和内标的保留时间分别为 8.7和 9.3min;日内RSD小于 4% ,日间RSD小于 9% ,方法回收率在 93 %～ 1 1 2 %。     

高效液相色谱法测定人血浆中奥氮平的浓度

 用高效液相色谱法测定了人血浆中奥氮平的浓度。色谱条件 :采用岛津LC 6A型高效液相色谱仪 ;色谱柱为ZorbaxODS (15 0mm× 4 6mmi d ,粒径 5 μm) ;流动相为V(5 0mmol/L磷酸钠缓冲液 ,pH 7 2 )∶V(甲醇 )∶V(乙腈 ) =12∶10∶3的溶液 ;检测波长为 2 70nm ;流速为 1 0mL/min ;柱温 40℃ ;灵敏度 0 0 0 5AUFS ;纸速 2mm/min。实验结果显示 ,在上述条件下 ,该方法的线性范围为 15 μg/L～ 12 0 0 μg/L(r =0 9988) ,最低检测限为 3μg/L ,血浆中奥氮平的平均回收率为 (97 0 2± 3 11) % ,测定结果的日内平均相对偏差为 3 86 % (n =15 ) 。     

反相高效液相色谱法同时测定祛痘类化妆品中的禁用物质

建立了用反相高效液相色谱法(RP-HPLC)同时测定祛痘类化妆品中禁用物质安体舒通、过氧化苯甲酰和维A酸的含量。采用甲醇超声提取,HPLC法分离测定。3种被测物在11 min内均得到良好的分离。在1～200 mg/L范围内其浓度与峰面积呈良好的线性关系(r≥0.9999);在添加质量浓度为1～10 mg/L时,回收率为88.2%～106.7%,相对标准偏差小于3.1%;最低检出限(S/N=3)为安体舒通0.101 μg,过氧化苯甲酰0.100 μg,维A酸0.107 μg。该法简便、快速、准确,可用于祛痘类化妆品中以上3种禁用物质的检测。     

反相高效液相法测定血清中的佐匹克隆

 建立了测定血清中佐匹克隆的反相高效液相法 (外标法 )。血样用正丁基氯提取后进行分离。采用的柱为LiChroCART 12 5 4柱 (LiChrospher 6 0RPselectB填料 ,5 μm ,12 5mm× 4mmi d ) ,流动相为乙腈 0 0 2mol/LKH2 PO4缓冲溶液 (体积比为 2 0∶80 ) ,紫外检测波长为 2 5 4nm。当佐匹克隆在血清中的添加质量浓度分别为 4 0 0 μg/L ,16 0 0 μg/L和6 4 0 0 μg/L时 ,血清中佐匹克隆的回收率分别是 (73 4± 3 2 ) % ,(82 2± 4 1) %和(90 3± 4 5 ) %。方法的最低检出限为 15 μg/L。方法适用于法庭毒物分析 ,简便、快速。     

反相高效液相色谱法测定犬血清及组织中的维拉帕米

建立了动物血清、肝组织中维拉帕米(verapamil,VRPM)药物浓度的测定方法。 应用反相高效液相色谱法,以安定为内标,采用峰高内标法计算结果。流动相为醋酸盐缓冲液-甲醇-三乙胺(体积比为40∶60∶1)混合溶液,流速1.0 mL/min;检测波长228 nm。 VRPM在犬血清和肝组织中最低检测限分别为50 μg/L和50 ng/g。犬血清和肝组织匀浆中的VRPM质量浓度为0.1～10.0 mg/L及0.25～10.0 μg/g时,该浓度与响应值线性关系良好(r＞0.999)。犬血清和肝组织匀浆中的     

以睾酮为探针采用高效液相色谱法测定细胞色素CYP450 3A4的酶活性

建立了一种快速、高效的以睾酮作为探针药物评价细胞色素P450 3A4(CYP3A4)酶活性的高效液相色谱-紫外检测方法。采用的色谱柱为Phenomenex C18柱(4.6 mm×150 mm,5 μm),梯度洗脱,流速1.0 mL/min,紫外检测波长245 nm,柱温30 ℃。睾酮与大鼠肝微粒体温孵后,过已活化好的C18固相萃取小柱,收集甲醇洗脱液,于37 ℃水浴中通N2吹干,用50%甲醇复溶后进样分析测定。研究结果表明,6β-羟基睾酮的 保留时间为11.60 min,线性范围为0.5～32 μg/mL,最低检出质量浓度为0.02 μg/mL,提取率为88.41%～92.73%,方法的回收率为99.07%～101.30%;睾酮的保留时间为19.27 min,线性范围为0.5～40 μg/mL,最低检出质量浓度为0.01 μg/mL,提取率为89.59%～92.66%,方法的回收率为96.50%～98.03%。两者的日内、日间相对标准偏差均小于10%,温孵体系中的其他内源性物质不干扰测定。该方法快速、稳定、灵敏度高,适合体外睾酮及其代谢物6β-羟基睾酮的测定,可应用于体外CYP3A4酶活性的评价及酶动力学的研究。     

液相色谱-串联质谱法测定食品接触材料及制品中新戊二醇迁移量

采用液相色谱－串联质谱（LC－MS/MS）建立了食品接触材料及制品中新戊二醇的测定方法。样品采 用水、4%（体积分数,下同）乙酸、10%乙醇、20%乙醇、50%乙醇、95%乙醇和橄榄油作为食品模拟物进行 迁移试验后,水、4%乙酸、10%乙醇浸泡液直接过滤进样,其他乙醇类模拟物浸泡液采用氮吹方式去除大部 分乙醇后重新用水定容,橄榄油浸泡液采用 10% 乙醇萃取。经处理后的试液采用 ACQUITY UPLC? BEH C18 （50 mm × 2. 1 mm,1. 7 μm）色谱柱,以0. 01%甲酸溶液－乙腈为流动相进行梯度洗脱,在电喷雾离子源正离 子（ESI+ ）多反应监测（MRM）模式下进行检测,外标法定量。在优化条件下,新戊二醇在10～100 μg/L（μg/kg） 范围内线性关系良好,相关系数大于 0. 999。在 10、20、100 μg/L（μg/kg）3 个加标水平下,方法回收率为 92. 8%～117%,相对标准偏差（RSD）为0. 90%～8. 6%,检出限（LOD,S/N ≥ 3）为5 μg/L（μg/kg）,定量下限（LOQ, S/N ≥ 10）为10 μg/L（μg/kg）。该方法具有前处理简单易行、灵敏度高、稳定可靠的优点,涉及的食品模拟物 基本包括相关法规和标准中规定的类型,方法LOD和LOQ均低于相关法规和标准中的限量要求,能够满足食 品接触材料及制品中新戊二醇迁移量的检测需求,为相关产品监管和质量控制提供了可靠的技术手段。     

气相法分析3-氯-2-羟丙基三甲基氯化铵中的微量有机杂质

 以氯仿为萃取剂 ,对 3 氯 2 羟丙基三甲基氯化铵 (CHPTMA)水溶液进行萃取 ,用气相法分析了CHPT MA溶液中的微量有机杂质环氧氯丙烷和 1 3 二氯丙醇。柱为 2m× 3mmi d 的不锈钢填充柱 ,固定相为10 %的PEG 2 0M ,载体为ChromosorbW/AW。环氧氯丙烷和 1,3 二氯丙醇的回收率分别为 97 5 %～ 10 5 0 %和93 3%～ 98 8% ,相对标准偏差分别为 11 5 %和 13 1% ,最低检测限分别为 5 0 μg/g和 10 0 μg/ g。     

反相高效液相色谱法同时测定化妆品中的尿囊素和泛醇

采用反相高效液相色谱法同时分离测定化妆品中的尿囊素和泛醇。用YWG C 18 柱(250 mm×4.6 mm i.d., 10 μm)分离,以0.02 mol/L 磷酸二氢钾-甲醇(体积比为90∶10)为流动相,检测波长210 nm。尿囊素的最低检测量为8 ng,最低检测浓度为0.4 mg/L ;泛醇的最低检测量为32 ng,最低检测浓度为1.6 mg/L 。尿囊素和泛醇的回收率分别为82.03%～103.80%和95.50%～109.12%;选择唇膏等4个不同样品作了精密度实验,样品中目标组分含     

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%.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

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.     

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

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.