新型双氢青蒿素哌嗪-脂肪族酰胺类化合物的合成及其抗癌活性

以双氢青蒿素（DHA）为原料,与草酰氯和哌嗪经“一锅”法制得DHA哌嗪衍生物（2）; 2与脂肪族酰氯经酰化反应合成了6个新型的双氢青蒿素哌嗪-酰胺类衍生物（4a～4f）,其结构经¹H NMR, ¹³C NMR,IR和HR-ESI-MS进行表征。以四甲基偶氮唑盐比色法（MTT法）初步研究了4a～4f对人肝癌细胞株SMMC-7721的抑制活性。结果表明,4a～4f显著抑制SMMC-7721的增殖,并诱导其凋亡。其中,双氢青蒿素哌嗪-氯乙酰胺（4c）的活性最好,IC₅₀为0.05 μM,优于青蒿素（IC₅₀ 0.53 μM）和DHA（IC₅₀0.52 μM）。     

表面增强喇曼光谱技术应用于生物体系的最新进展

本文综述了近几年来表面增强喇曼光谱技术应用于以下几个方面的生物体系的最新资料：（１）核酸及其组分，（２）蛋白质及其组分，（３）儿茶酚胺，（４）有色生物质，（５）膜制品。总结了表面增强喇曼光谱技术的一般性结论，并对这一技术应用于生物体系的发展作了展望     

N-甲基-N′-氨基哌嗪及某些哌嗪衍生物的气液色谱分析

本文报导N-甲基-N′-氨基哌嗪及某些哌嗪衍生物的气液色谱分析方法。合成并提纯了若干化合物作分析的标准品。采用6201红色担体,以氢氧化钾作去尾剂,聚乙二醇-12000为固定液,在长2米、内径2毫米的色谱柱上,哌嗪衍生物得到良好的分离。用峰高内标法定量,相对误差在2％以下。     

抗肿瘤药布格替尼的合成

以2-碘苯胺为起始原料,经“一锅法”反应制得{2-[（2,5-二氯嘧啶-4-基）氨基]苯基}二甲基氧化膦（3）; 1-甲基-4-（哌啶-4基）哌嗪（4）与5-氟-2-硝基苯甲醚反应后,经氢化还原得2-甲氧基-4-[4-（4-甲基哌嗪-1-基）哌啶-1-基]-苯胺（6）; 3和6反应合成了布格替尼,总收率48.5%,纯度99.6%,其结构经¹H NMR和MS（ESI）确证。     

2,5-二酮哌嗪衍生物的一锅法合成及其细胞毒活性

以DMF为溶剂,Cs₂CO₃为碱, N,N-二乙酰基-2,5-二酮哌嗪,芳醛和卤代烷经一锅法合成了１10个2,5-二酮哌嗪类衍生物（4a~4j,其中4c, 4f和4i为新化合物）,收率54.2％～75.7％,其结构经¹H NMR, ¹³C NMR和ESI-MS确证。生物活性研究结果表明：（Z）-1-乙酰基-3-（1-亚甲基萘）-4-烯丙基-2,5-二酮哌嗪（4c）对U937, Hela和Du145等细胞具有一定的细胞毒活性。     

三种尾式卟啉的合成及结构表征

5-（4-羟基苯基）-10，15，20-（4-甲氧基苯基）卟啉（1）与乙酰水杨酰氯 反应得到化合物3.5-[4-（4-溴丁氧基）苯基]-10，15，20-三（4-甲氧基苯基）卟 啉（2）分别与苯基哌嗪和1-（4-甲氧基苯基）哌嗪作用，制得了化合物4和5。合 成的新化合物分别经吸收光谱，^1H NMR，MS和元素分析所证实。     

含Mn-O链的层状锰4-膦酸问苯二甲酸（4-piH4）化合物及Mn3（4-piH）2（H2O）3·H2O的变磁性质

通过加入模板剂哌嗪以及辅助配体1,10-菲哕啉,在水热条件下合成得到了两个金属有机膦酸化合物Mn3（4-piH）2（H2O）3·H2O（1）和Mn5（4-pill）2（4-piH2）2（phen）2（H2O）4（2）（4-piH4为4-膦酸间苯二甲酸）．两者都显示层状结构．在化合物1中,由三角形的{Mn3O3}三聚体通过共边或共角组成fMn303}02复杂柱型链,链与链之间由{PO3C}连接形成无机层,苯基以及未配位的羧基悬挂在无机层的两侧．在化合物2中,由{Mnl0。1和{Mn3O4N2）八面体共边形成（Mna06}四核簇,四核簇之间通过{Mn2O6}八面体共角连接形成一维之字形无机链,相邻链间由4-pi^4-配体连接形成无机有机杂化的二维层状结构．磁性研究表明两个化合物中锰离子之间均存在反铁磁相互作用,在低温下化合物1表现出变磁体的行为．     

新型含哌嗪-磺酰胺的2(5H)-呋喃酮类化合物的合成及其抗癌活性

以糠醛为原料,经氧化、醚化和重结晶制得5-甲氧基-3,4-二溴-2(5H)-呋喃酮（4）; 4与哌嗪经Michael加成消除反应制得5-甲氧基-4-哌嗪基-3-溴-2(5H)-呋喃酮（5）; 5与取代磺酰氯经磺酰化反应合成了7 个新型的含哌嗪-磺酰胺的2(5H)-呋喃酮类化合物(7a~7g),其结构经¹H NMR, ¹³C NMR, IR和HR-MS表征。初步的生物活性研究(MTT法)表明,7a~7g均能显著抑制人宫颈癌Hela细胞的增殖,其中5-甲氧基-4-(对乙酰氨基苯磺酰基-哌嗪基)-3-溴-2(5H)-呋喃酮（7f）的抑制活性最佳,其IC₅₀为0.03 μM(24 h)。     

N-酰基-N′-茄呢基哌嗪衍生物的合成及生物活性

以茄呢醇为起始原料和茄呢基哌嗪为关键中间体合成了 4个N 酰基 N′ 茄呢基哌嗪 ( 4a～ 4d) ,以及 2个含葡萄糖单元的N ( 2 全乙酰葡萄糖基苯甲酰基 ) N′ 茄呢基哌嗪 ( 5 )和N ( 2 葡萄糖基苯甲酰基 ) N′ 茄呢基哌嗪 ( 6) ,共 6个新茄呢基哌嗪衍生物 .其结构经元素分析 ,IR ,1HNMR和MS确证 .测试了化合物 4c ,5 ,6对三种人癌细胞 (Bel 740 2 ,KB ,HCT 8)的体外生理活性 ,初步结果表明化合物 6比 4c和 5对三种所测细胞有更好的抑制效果     

N-酰基-N''''-茄呢基哌嗪衍生物的合成及生物活性

以茄呢醇为起始原料和茄呢基哌嗪为单元的N-(2-全乙酰葡萄糖基苯甲酰基)-N'-茄呢基哌嗪(5)和N-(2-葡萄糖基苯甲酰基)-N'-茄呢基哌嗪(6),共6个新茄呢基哌嗪衍生物.其结构经元素分析,IR,1H NMR和MS确证.测试了化合物4c,5,6对三种人癌细胞(Bel-7402,KB,HCT-8)的体外生理活性,初步结果表明化合物6比4c和5对三种所测细胞有更好的抑制效果.     

A new method for the determination of residual piperazine in pharmaceuticals by capillary gas chromatography

A new selective open tubular capillary gas chromatographic method is developed for the determination of trace amounts of piperazine. Piperazine is extracted from pharmaceuticals into cyclohexane and is partitioned with water. The aqueous solution is then injected into a 5% crosslinked Ph-Me silicone column programmed at 50-180 degrees C for 10 min. Piperazine is eluted after 3.18 min under isothermal conditions. The lower limit of determination is 0.4 ppm. This method has been successfully applied for the assay of piperazine in pharmaceutical formulations and its trace determination in fluoroquinolone drugs such as norfloxacin and ciprofloxacin. The method is reproducible and the standard and relative standard deviation for 10 repeated injections of 2 mug piperazine are 0.7 and +/-2.1% respectively.     

A rapid spectrophotometric method for determination of piperazine

A spectrophotometric method has been developed for the determination of piperazine and its salts (citrate, phosphate, and tartrate) without prior separation, based on the interaction of piperazine or any of its salts with phenothiazine and N-bromosuccinimide in aqueous methanol. The products exhibit absorption maxima at 448, 595 and 645 nm. Measurements are made at 595 nm. Beer's law is obeyed in the concentration range 0.5-5 mug/ml for piperazine salts and 0.5-3 mug/ml for piperazine hexahydrate. The method is rapid, simple and successful for analysis of some pharmaceutical preparations.     

茜素红荷移光度法测定阿魏酸哌嗪

研究了茜素红与阿魏酸哌嗪的显色反应,建立了阿魏酸哌嗪含量测定的分光光度法.在水溶剂中阿魏酸哌嗪与茜素红发生荷移反应生成紫红色的复合物,其最大吸收波长为524nm,表观摩尔吸光系数为1.86×103 L·mol-1·cm-1.阿魏酸哌嗪的浓度在1.60⁴8.0mg·L-1范围内与体系的吸光度呈良好的线性关系,其线性回归方程为A=0.021 07+0.003 93c(mg·L-1,R=0.999 2),方法的检出限为1.19mg·L-1.将此新方法应用于阿魏酸哌嗪片中阿魏酸哌嗪含量的测定,回收率在97.5%48.0mg·L-1范围内与体系的吸光度呈良好的线性关系,其线性回归方程为A=0.021 07+0.003 93c(mg·L-1,R=0.999 2),方法的检出限为1.19mg·L-1.将此新方法应用于阿魏酸哌嗪片中阿魏酸哌嗪含量的测定,回收率在97.5%¹00.9%之间.     

Analysis of flunarizine in the presence of some of its degradation products using micellar liquid chromatography (MLC) or microemulsion liquid chromatography (MELC)--application to dosage forms

The separation of flunarizine hydrochloride (FLZ) and five of its degradation products--1-[bis(4-fluorophenyl)methyl]-4-(3-phenyl-2-propenyl)piperazine, 4-oxide (A), bis(4-fluorophenyl)methanone (B), bis(4-fluorophenyl)methanol (C), 1-(3-phenyl-2-propenyl)piperazine(D), and 1-[bis-4-fluorophenyl) methyl] piperazine (E)--could be accomplished by reversed phase liquid chromatography using either micellar or microemulsion mobile phases. Cyanopropyl-bonded stationary phase has been used with UV detection at 254 nm. Microemulsion mobile phase consisting of 0.15 M SDS, 10% n-propanol, 1% n-octanol, and 0.3% triethylamine in 0.02 M phosphoric acid of pH 7.0, has been used for the separation of FLZ and its degradation products (B, C, D, and E). Micellar mobile phases consisting of 0.15 M sodium dodecyl sulphate (SDS), 10% n-propanol, 0.3% triethylamine (TEA) in 0.02 M phosphoric acid of pH values either 4.0 or 6.8 have been used for the separation of FLZ from its degradation products, i.e. either from (B, C, D, and E) or from (A, B, C, and D), respectively. Micellar liquid chromatography (MLC) was applied to the determination of FLZ in pure form as well as in dosage forms; the calibration graph was linear over the concentration range of 0.15-50 microg/mL with detection limit of 0.02 microg/mL (4.19 x 10(-8)M).     

Piperazines for peptide carboxyl group derivatization: effect of derivatization reagents and properties of peptides on signal enhancement in matrix-assisted laser desorption/ionization mass spectrometry

Piperazine-based derivatives, including 1-(2-pyridyl)piperazine (2-PP), 1-(2-pyrimidyl)piperazine (2-PMP), 1-(4-pyridyl)piperazine (4-PP), and 1-(1-methyl-4-piperidinyl)piperazine (M-PP), were used for the derivatization of carboxyl groups on peptides with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and 1-hydroxy-7-azabenzotriazole (HOAt) as coupling reagents, and trifluoroacetic acid (TFA) as activator. Taking synthetic peptides RVYVHPI (RI-7) and APGDRIYVHPF (AF-11) as samples, the yields of derivatized peptides by 2-PP, 2-PMP and 4-PP were higher than 94%. The effect of piperazine derivatives on the signals of tryptic digests of α-transferrin and bovine serum albumin (BSA) was investigated, and it was found that peptides derivatized by 2-PP and 2-PMP exhibited obviously improved ionization efficiency. Furthermore, comparison of identified peptides before and after derivatization showed that peptides with low molecular weight (MW) and high pI value were preferably detected after derivatization. In addition, after derivatization with 2-PP and 2-PMP, protein myelin basic protein S, 20 kDa protein, and histone H were confidently identified from the tryptic digests of two fractions of rat brain protein separated by reversed-phase high-performance liquid chromatography (HPLC), indicating the potential application of 2-PP and 2-PMP for the highly sensitive determination of peptides in comprehensive proteome analysis.     

Determination of piperazine in working atmosphere and in human urine using derivatization and capillary gas chromatography with nitrogen- and mass-selective detection

A reliable routine method is presented for the determination of piperazine down to the sub-ppm level in aqueous solutions and in urine. The method includes a two-phase derivatization procedure with ethyl- or isobutyl chloroformate as the reagent, followed by a capillary gas chromatographic determination using nitrogen- or mass selective detection. The addition of ammonia ensured a quantitative recovery. Detection limits for piperazine in urine were ca. 20 ng/ml using nitrogen-selective and ca. 1 ng/ml with mass-selective detection. The calibration plots were linear in the investigated range, 100-10,000 ng/ml with nitrogen-selective and 30-3000 ng/ml with mass-selective detection. The precision was ca. 6% at a concentration of 300 ng/ml. Acid anhydrides were investigated as alternative reagents in the two-phase derivatization procedure, and heptafluorobutyric acid anhydride in aqueous solutions gave approximately 100% recovery. However, in urine the recoveries of the investigated acid anhydride derivatives were unsatisfactory.     

哌嗪-二氧化硫电荷转移复合物引发的甲基丙烯酸甲酯光聚合

本文研究了哌嗪 (PPZ)与二氧化硫 (SO2 )电荷转移复合物 (CTC)的制备及其作为光引发剂引发甲基丙烯酸甲酯 (MMA)的聚合 ,发现PPZ/SO2 摩尔比对聚合速率影响甚大 .当PPZ/SO2 为 1∶2时 ,形成了具有潜在引发能力的复合物 (Ⅰ ) .Ⅰ引发MMA光聚合的动力学关系式为Rp =Kp [Ⅰ ] 0 .34[MMA] 1.0 6 ,表观活化能为 2 3 7kJ/mol.并对引发机理进行了探讨     

Kinetic and thermodynamic acidities of substituted 1-benzyl-1-methoxy-2-nitroethylenes. Strong reduction of the transition state imbalance compared to other nitroalkanes

Acidity constants of six substituted 1-benzyl-1-methoxy-2-nitroethylenes (2-Z with Z = m-NO(2), m-CF(3), m-Cl, H, p-Me, p-MeO) and their respective nitronic acids were determined in 50% DMSO-50% water (v/v) at 20 degrees C. Kinetic data were obtained on the reversible deprotonation of all six 2-Z by OH(-) and piperidine and on the reversible deprotonation of 2-NO(2)() by piperazine, 1-(2-hydroxyethyl)piperazine, and morpholine in the same solvent. These data allowed a determination of the Br?nsted coefficients alpha (dependence on acidity of 2-Z) and beta (dependence on amine basicity). The fact that alpha > beta indicates the presence of a transition state imbalance which, however, is much smaller than that for the deprotonation of arylnitromethanes. The reasons for this reduction in the imbalance and their relevance to a recent study of the deprotonation of Fischer carbene complexes are discussed.     

A simple spectrophotometric determination of some chlorobenzoquinones with morpholine, thiomorpholine and piperazine

A spectrophotometric method for the determination of 2,5-dichloro-, 2,6-dichloro- and 2,3,5,6-tetrachloro-1,4-benzoquinones is based on the yellow products of their reaction with morpholine, thiomorpholine and piperazine in chloroform.     

Electrochemical oxidation of sildenafil citrate (Viagra) on carbon electrodes

In aqueous solutions containing 30% (v/v) acetonitrile the unprotonated form of the piperazine ring of sildenafil (I) is oxidized on a glassy carbon electrode between pH 2 and 8. Whereas citrate anions under conditions used are not oxidized, the oxidation pattern of sulfonamides differs from that of sildenafil (I). On the other hand, the oxidation of I resembles that of the oxidation of piperazine ring in nefazodone (III) and trazodone (IV). A more positive peak of sildenafil corresponds to an adsorption-desorption process. Measurement of the peak current enables rapid determination of sildenafil (I) in pharmaceutical preparations with sufficient accuracy.