气相色谱与串联质谱联用检测血清中脱氢表雄酮

在晚期前列腺癌雄激素全阻断治疗最终导致前列腺癌雄激素非依赖性的转变过程中,肾上腺分泌脱氢表雄酮(DHEA)被认为是重要的诱因。本研究主要利用睾丸摘除(去势)大鼠模型,对血清中DHEA浓度进行测定。采用了气相色谱与串联质谱联用(GC-MS/MS)技术,建立了高灵敏度的测定大鼠血清中脱氢表雄酮(DHEA)的方法。样品经过甲醇沉蛋白,而后固相萃取提取血清中微量的DHEA,通过七氟丁酸酐(HF-BA)衍生,采用GC-MS/MS测定。对固相萃取条件、衍生化条件以及质谱测定条件进行优化。DHEA在0.1~100μg/L范围内线性良好,相关系数r为0.9996;在2~50μg/L浓度范围内,加标回收率在99%~106%之间;相对标准偏差小于5%。本方法灵敏度高,选择性好,可满足临床对于血清样品中DHEA的测定要求。对去势大鼠血清中DHEA测定结果表明,去势后DHEA明显上升。     

2-(2-噻唑偶氮)-对-甲酚螯合物反相高效液相色谱同時分离测定镍、钴的研究——合金中微量钴和镍的测定

本文研究了2-(2-噻唑偶氮)-对-甲酚(TAC)与镍(Ⅱ)、钴(Ⅱ)螯合物的柱前衍生条件和液相色谱的分离条件。于KYWG-C_(18)柱上,用含有0.03mol/L KH_2PO_4-Na_2HPO_4(pH7.77)和2.5×10~(-4)mol/L TAC的甲醇-四氢呋喃-水(40∶10∶50 V/V)混合液为流动相,流速为1.0mL/min。于580nm处检测。该法用于四种标准合金中镍和钴的测定,回收率在98%～101.5%之间。Ni(Ⅱ)和Co(Ⅱ)的检出限(信噪比为2∶1)分别为0.2ng和1.5ng。建立了同时测定镍,钴的高灵敏、高选择性,快速的HPLC-光度法。     

纳米Fe3O4分离富集-悬浮进样-氢化物发生原子荧光法测定砷形态

研究了以纳米Fe3O4为固相吸附剂对痕量无机砷形态的吸附与分离富集,建立了无需洗脱分离的悬浮进样-氢化物发生-原子荧光法测定砷形态的方法。选择的反应体系为0.64 g/L Fe3O4悬浮液-1.0%(m/V)NaBH4溶液-5.0%(V/V)HCl(pH 8),进样5.0 mL时,得到本方法的检出限为13.5 ng/L;As(Ⅲ)浓度在0.05～3.5μg/L范围内呈良好的线性关系;测定0.5μg/L As(Ⅲ)的精密度RSD=3.4%。用国家标准物质GBW10010(大米)验证了本方法测定砷的准确性,测定结果(0.101±0.010μg/g)与标准值(0.102±0.008μg/g)吻合。采用本方法测定了近海海水和雪水样品中的无机砷形态,并进行了加标回收实验。对As(Ⅲ)和As(Ⅴ)的加标回收率在95%～110%之间,结果令人满意。     

从细脚拟青霉分离的新环二肽与新十元环内酯

利用反相色谱、 凝胶色谱和硅胶色谱从细脚拟青霉发酵液中分离得到4个活性化合物. 通过核磁共振波谱、 质谱、 X射线晶体衍射分析和理化数据鉴定化合物1为新环二肽[(3S)-6-苯乙基-3-异丙基-1-甲基-2,5-二酮哌嗪], 化合物2为新十元环内酯[(4S,10R)-4-羟基-8-氧代-10-甲基癸内酯], 化合物3为Cepharosporolide C, 化合物4为Cepharosporolide E. 细胞毒性实验结果表明, 5 μmol/L的化合物1对前列腺癌细胞22RV1和DU-145的抑制率分别为37.8%和38.6%, 5 μmol/L的化合物2对前列腺癌细胞22RV1和DU-145的抑制率分别为32.5%和40.6%, 具有一定抗肿瘤活性.     

反相高效液相色谱法(RP-HPLC)测定酒花浸膏中的异构化α-酸

建立了一种利用反相高效液相色谱法(RP-HPLC)测定酒花浸膏中4种异构化α-酸的方法。异α-酸、二氢异α-酸、四氢异α-酸和六氢异α-酸在色谱柱EC250/4 Nuclesoil,100-5 C18(4.0 mmi.d.×250 mm,5μm),保护柱CC 8/4Nuclesoil 100-5 C18,流动相为V(甲醇)∶V(水)∶V(85%H3PO4)∶V(0.2 mol/LEDTA二钠盐)=770∶210∶5∶1,等梯度洗脱,流速为1.2 mL/min,270 nm紫外检测,加标回收率在93.5%~97.0%之间,RSD<2%。该方法可测定酒花浸膏中异构化α-酸。     

9,9-二甲基-2-(4-硝基苯基)-4-苯基-9H-吡啶并[1,2-a]吲哚高氯酸盐的微波合成及晶体结构

在微波辐射条件下,由2,3,3-三甲基-3H-吲哚高氯酸盐、1-苯基-3-(4'-硝基苯基)-2-丙烯-1-酮与哌啶合成了标题化合物.在甲醇/乙醇=1/1(V/V)中培养出单晶,通过X射线单晶结构分析法测定了分子结构和晶体结构,晶体属于单斜晶系,P2(1)/n空间群,其晶胞参数为:a=1.2507(4)nm,b=1.4378(4)nm,c=1.3033(4)nm,V=2.3366(12)nm3,Dc=1.401g/cm3,μ=0.210mm-1,F(000)=1024,Z=4,R1=0.0553,wR2=0.0732.     

反相HPLC测定钒、铌、钽的2-(2-吡啶偶氮)-5-二乙氨基苯酚配合物

以2-(2-吡啶偶氮)-5-二乙氨基苯酚(PADAP)为柱前衍生试剂,在含0.1%酒石酸的10mmo1/L(pH3.5)HAc-NaAc缓冲溶液的甲醇/水(50:50,V/V)中(580nm检测),在C₁₈柱上于11min内实现了V、Nb、Ta的同时分离及测定,检出限(S/N=3)为0.34、0.29、7.30ng/mL.该法灵敏度高,用于矿样分析所得结果与推荐值相符,标准加入回收率为99.0%～101.1%.     

4-(6-甲基-2-苯并噻唑偶氮)间苯二酚作螯合剂反相HPLC分离测定V(V)、cu(Ⅱ)、co(Ⅱ)、Ni(Ⅱ)、cr(VI)

本文提出用4-(6-甲基-2-苯并噻唑偶氮)间苯二酚(MBTAR)为柱前衍生试剂,用含有15mmol/L TBA·Br,10mmool/L pH6.0 HAc-NaAc缓冲溶液的甲醇-水(75/25,V/V)混合溶液作流动相,在C_8柱上分离和测定了V(V)、Cu(Ⅱ)、Ni(Ⅱ)、co(Ⅱ)和Cr(Ⅵ)。当信噪比为3时,其检出限为0.15～6.1ppb。本法干扰少,分离时间短,应用于人发分析,结果令人满意。     

高效液相色谱-串联质谱法同时测定牛奶和奶粉中的青霉素类药物及其主要酶解代谢产物

建立了液相色谱-串联质谱法同时测定牛奶和奶粉中4种青霉素(青霉素G、青霉素V、阿莫西林、氨苄西林)及其4种 β-内酰胺酶酶解产物(青霉素G脱羧噻唑酸、青霉素V脱羧噻唑酸、阿莫西林脱羧噻唑酸、氨苄西林脱羧噻唑酸)残留的方法。样品采用乙腈-水提取,浓缩后经HLB柱净化,用液相色谱-串联质谱检测,外标法定量。结果表明,青霉素原药在4~200 μg/L,酶解产物在10~500 μg/L范围呈良好线性,线性相关系数均大于0.99;样品检出限为5~50 μg/kg(S/N≥3),定量限为8~100 μg/kg(S/N≥10);对牛奶和奶粉样品分别进行3个水平的加标回收实验(n=6),牛奶中青霉素及其酶解产物的平均回收率为83.48%~96.97%,相对标准偏差为3.86%~10.87%;奶粉中青霉素及其酶解产物的平均回收率为82.70%~95.14%,相对标准偏差为3.02%~9.81%。该方法稳定、可靠,适用于牛奶和奶粉中青霉素类药物及其酶解代谢产物的测定。     

铌(V)-1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5络合物吸附波的研究

在pH=5.0的HAc-NaAc介质中,Nb(V)与1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5(PMBP)生成络合物,于-0.96V(us.SCE)出现一尖锐的极谱波.在滴汞电极上用示波极谱仪或在悬汞电极上测吸附伏安曲线.峰电流与Nb(V)浓度分别在0.0075~0.80μg/mL及0.000075~0.0075μg/mL范围内呈线性关系.实验了30多种离子的干扰影响,经苯肿酸分离后用于钢中Nb(V)的测定.检出限为0.00003μg/mL.溶液可稳定96h以上.用多种电化学方法研究了电极反应机理.     

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.