酚醛冠醚共缩聚物的合成与性能

用2,6-二羟甲基-4-苯基苯酚分别与二苯并-18-冠-6(2B18C6)、二苯并-24-冠-8(2B24C8)、二苯并-30冠-10(2B30C10)、苯并-15-冠-5(B15C5)、苯并-18-冠-6(B18C6)缩聚合成了五种酚醛型冠醚共聚物。我们用聚冠醚的氯仿溶液萃取苦味酸碱金属盐水溶液,研究了它们对金属离子的络合性能。结果表明,聚冠醚(PB15C5)和(PB18C6)的萃取能力和选择性显著优于相应的单冠醚。     

四Schiff碱(二苯并-18-冠-6)及其钾(I)/钴(II)配合物的合成和 性质

由二苯并-18-冠-6出发,合成了4',4',5',5'-四(2-羟基苯亚甲基亚氨基)二苯并-18-冠-6(L^1H~4)及其5位取代衍生物(取代基R=CH~3,OH,OCH~3,Cl,NO~2)L^2H~4～L^6H~4。它们依次与硝酸钾和醋酸钴反应,制得1:1:2的钾(I)/双钴(II)配合物LCo~2.2H~2O.KNO~3(L=L^5,L^6)或其某些二氧加合物LCo~2(2O~2).2H~2O.KNO~3(L=L^1～L^4)。考察了取代基R和冠醚环配合的钾离子对二氧加合物形成及稳定性的影响。结果表明,含吸电子基(R=Cl,NO~2)的钾(I)/双钴(II)配合物不能形成二氧加合物;冠环中的钾离子会导致二氧加合物中两个Co-O~2键热稳定性的差异。     

四Schiff碱(二苯并-18-冠-6)及其钾(I)/钴(II)配合物的合成和 性质

由二苯并-18-冠-6出发,合成了4',4',5',5'-四(2-羟基苯亚甲基亚氨基)二苯并-18-冠-6(L^1H~4)及其5位取代衍生物(取代基R=CH~3,OH,OCH~3,Cl,NO~2)L^2H~4～L^6H~4。它们依次与硝酸钾和醋酸钴反应,制得1:1:2的钾(I)/双钴(II)配合物LCo~2.2H~2O.KNO~3(L=L^5,L^6)或其某些二氧加合物LCo~2(2O~2).2H~2O.KNO~3(L=L^1～L^4)。考察了取代基R和冠醚环配合的钾离子对二氧加合物形成及稳定性的影响。结果表明,含吸电子基(R=Cl,NO~2)的钾(I)/双钴(II)配合物不能形成二氧加合物;冠环中的钾离子会导致二氧加合物中两个Co-O~2键热稳定性的差异。     

三-2-吡喃酮与二苯酮的固相[2+2]光环加成反应

4-羟基-6-甲基-2-吡喃酮分别与原甲酸三氯乙酯,三(溴甲基)氧磷和1,3,5-三(溴甲基)苯经取代反应制得三-2-吡喃酮(3a~3c);3a和3b分别与二苯酮(4)通过经历4的三线激发态,横穿3的C5-C6,C5'-C6'和C5″-C6″双键经固相[2+2]光环加成反应,高位置、高配向选择性地合成了4个新型的氧杂类化合物(5a,5a',5b和5b'),其结构经1H NMR,13C NMR,IR,LR-MS和HR-MS表征。     

冠醚化单和双Schiff碱的合成及其钴(II)配合物的氧加合性能

由苯并-15-冠-5经硝化、还原和缩合反应,制备了4'-(2-羟基苯亚甲基亚氨基)苯并-15-冠-5(L^1H)和4',5'-双(2-羟基苯亚甲基亚氨基)苯并-15-冠-5(L^4H~2)以及它们的取代衍生物L^2H和L^5H~2。在不同温度和不同轴配体存在下,测定了它们的钴(II)配合物的氧合常数和ΔHⅲ,ΔSⅲ,并与未冠醚化的类似物CoL~2^3和CoL^6比较,讨论了配体结构和轴配体碱性对配合物的氧分子加合性能的影响。     

冠醚化单和双Schiff碱的合成及其钴(II)配合物的氧加合性能

由苯并-15-冠-5经硝化、还原和缩合反应,制备了4'-(2-羟基苯亚甲基亚氨基)苯并-15-冠-5(L^1H)和4',5'-双(2-羟基苯亚甲基亚氨基)苯并-15-冠-5(L^4H~2)以及它们的取代衍生物L^2H和L^5H~2。在不同温度和不同轴配体存在下,测定了它们的钴(II)配合物的氧合常数和ΔHⅲ,ΔSⅲ,并与未冠醚化的类似物CoL~2^3和CoL^6比较,讨论了配体结构和轴配体碱性对配合物的氧分子加合性能的影响。     

4'',4″(5″)-{二-[1,3]二氧[4,5-g]喹啉}-二苯并-18-冠-6的合成

6-氨基胡椒醛与4',4″(5″)-二乙酰基二苯并-18-冠-6进行Friedlnder缩合得到新的冠醚衍生物--4',4″(5″)-{二-[1,3]二氧[4,5-g]喹啉}-二苯并-18-冠-6(3),产率62%.3的结构经UV, 1H NMR, 13C NMR, IR和MS表征.     

微波辐射下合成5-(2-甲基/三氟甲基-苯并咪唑-1-亚甲基)-3-(苯基/p-取代苯基)-2H-1'''',2'''',4''''-三唑[3,4-b]-1",3",4"-噻二嗪

分别采用微波辐射法和加热回流的常规方法,将1-氨基-2-(2-甲基/三氟甲基-苯并咪唑-1-亚甲基)-5-巯基-1,3,4-三唑与α-溴代芳基乙酮3a～3e反应,合成了一系列未见文献报道的1,2,4-三唑[3,4-b]-1',3',4'-噻二嗪类化合物4a～4e和5a～5e.微波辐射法具有反应时间短、产率高、副反应少等优点.标题化合物经元素分析,IR,1HNMR,MS确证结构.     

2,6-二甲基-3,5-二氯-4-吡啶酚糖苷的合成

在相转移催化条件下, 使 a-D-乙酰基化溴代的葡萄糖、半乳糖、葡萄糖醛酸甲酯1a, 1b, 1c分别与2,6-二甲基-3,5-二氯-4-吡啶酚(俗称氯吡醇, 氯羟吡啶)作用, 合成了氯吡醇的糖苷: 1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4,6-四-O-乙酰基-β-D-葡萄吡喃糖苷(2a), 1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4,6-四-O-乙酰基β-D-半乳吡喃糖苷(2b), 1-O-(2'6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4-三-O-乙酰基-β-D-葡萄吡喃糖醛酸甲酯(2c)。2a, 2b, 2c分别在甲醇中氨解, 相应得到: 1-O-(2', 6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-葡萄吡喃糖苷(3a), 1-O(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-半乳吡喃糖苷(3b),1-O-(2', 6'-二甲基-3',5'-二氯-(4'-吡啶基)-β-D-葡萄吡喃糖醛酸酰胺(3c)。2c用CH~3ONa/CH~3OH处理, 得到1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-葡萄吡喃糖醛酸甲酯(3d)。     

新型姜黄素类似物的微波合成及其抗氧化活性

采用微波法,取代苯甲醛分别与环戊酮和环己酮经克莱森-斯密特缩合反应制得中间体2,6-双苯亚甲基环己酮(2a~2e)和2,5-双苯亚甲基环戊酮(5a);2a~2e或5a分别与硫脲或尿素经Biginelli反应合成了8个新型的姜黄素类似物(3a~3e,4a,4c和6a),其结构经1H NMR,13C NMR,IR和MS表征。利用DPPH法比较3~6与姜黄素的抗氧化能力。实验结果表明:3~6的抗氧化能力均比姜黄素母核结构高;3比4和6的自由基清除能力强;随用药量增大,抗氧化能力呈现先增强后下降的趋势,并在0.09 mg·mL-1~0.12 mg·mL-1自由基清除率达最大。     

Profiling of esterified fatty acids as biomarkers in the blood of dengue fever patients using a microliter‐scale extraction followed by gas chromatography and mass spectrometry

An improved gas chromatography with mass spectrometry procedure was developed to highlight the esterified fatty acids in 100 μL blood of dengue fever patients in the early febrile phase versus healthy volunteers. 24 adult patients and 24 healthy volunteers were included in this study. The recoveries of targeted esterified fatty acids content were in the range of 92.10–101.00% using methanol/dichloromethane (2:1, v/v) as the extraction solvent. An efficient chromatographic separation of targeted 17 esterified fatty acid methyl esters was obtained. The limits of detection and quantification were within the range of 16–131 and 53–430 ng/mL, respectively. The relative standard deviation of intraday and interday precision values ranged from 0.4 to 5.0%. The statistical data treatment showed a significant decrease of the content of four saturated fatty acids, C14:0, C15:0, C16:0, and C18:0 (P value < 0.05), and also showed a decrease of the content of eight unsaturated fatty acids, C16:1, C18:3n6, C18:2n6, C18:1n9, C20:3n3, C20:4n6, C20:2, and C22:6n3 (P value < 0.05) in dengue fever patients. Moreover, the amount of three omega‐6 fatty acids including C18:3n6, C18:2n6, and C20:4n6 was dramatically decreased in the blood of dengue fever patients to a limit of 50 ± 10%.     

Decrease of glutathione and fatty acids during iron-induced lipid peroxidation inEhrlich ascites tumor cells

In order to investigate a possible relationship between the intensity of lipid peroxidation (LP) in tumor cells and their proliferative activity various methods to quantify LP are desirable. In this study the decrease in the contents of fatty acids and glutathione was measured by established methods inEhrlich ascites tumor (EAT) cellsin vitro, in which LP was stimulated by the addition of ferrous iron, either as free ion or as histidinate chelate.When EAT cells were incubated for 30 min at 37 °C in the presence of 5 mM FeSO₄ the following changes were observed in comparison to appropriate control cells: The content of reduced glutathione (GSH) and total glutathione (GSH+2 GSSG) decreased significantly by 24 and 30% respectively. The decrease of 4 unsaturated (C 18:1; C 18:2; C 20:4; C 22:6) and 2 saturated fatty acids (C 16:0; C 18:0) by about 15% on the average was statistically significant only for C 16:0 and C 20:4).More pronounced effects were observed with 5 mM Fe(II)-histidinate. GSH and GSH+2 GSSG decreased by 54% and 40%, resp. The decrease of fatty acids by about 40% on the average was significant for all of the 6 fatty acids tested. These results are in agreement with previous studies on LP in EAT cells showing Fe(II)-histidinate to be a more powerful promoter of LP compared with free ferrous ion. The observation, that the content not only of GSH but also of total glutathione was decreased in iron-treated tumor cells is in contradiction to the hypothesis that GSH may act as a mere redox mediator of LP under the conditions used and points to a consumption of GSH by several possible pathways. The finding of decreased levels of unsaturated as well as saturated fatty acids in the presence of Fe(II)-histidinate underlines the extraordinary potency of iron as an initiator and catalyst of LP.This work was supported by the Association for International Cancer Research, St. Andrews, U.K.     

Liquid membrane transport of supramolecular complexes of some amines and amino acids with macrocyclic ligands

The transport of some amines in protonated form was studied (viz. methylamine, dimethylamine, diethylamine andn-propylamine) and -amino acids (l-leucine,l-methionine,l-isoleucine,l-phenylalanine,l-valine,l--alanine andl-cysteine). The following macrocyclic ligands were used as carriers throughout the experiments: 15-crown-5 (15C5), 18-crown-6 (18C6), benzo-18-crown-6 (B18C6), dibenzo-18-crown-6 (DB18C6), diazacrown ether [2.2] (1,7,10,16-tetraoxa-4,13-diazacyclooctadecane) and cryptand [2.2.2] (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo [8.8.8] hexacosane). The active transport, assisted by pH gradient, of amino acids and amines in protonated form as ion pairs in the presence of picrate anion was performed. The experiments suggested the influence of the ligand size, the donor atom type, and the substituents on the transport phenomena.     

Synthesis of novel water-soluble linear and heterocyclic phosphino amino acids from 2-phosphinophenols or 2-phosphinophenolethers, formaldehyde and amino acids

Acyclic and cyclic amino acid derivatives of 2-phosphinophenols have been synthesised by reaction of primary phosphinophenols (4-R-2-H₂PC₆H₃OH; R=H, Me, OMe) 1a–c with formaldehyde and amino acids (o- and p-aminobenzoic acid, -lysine) via in situ formed hydroxymethyl species 2a–c. Condensation reactions with glycine did not afford defined products except when the methoxymethyl and tetrahydropyranyl ethers of 1d,e were used instead of the hydroxy compounds. o-Aminobenzoic acid gives rise to linear bis(o-carboxyphenylaminomethyl)phosphines 3a–e. p-Aminobenzoic acid, dependent on the molar ratio, affords bis(p-carboxyphenylaminomethyl)phosphines 4a,d as well as eight-membered heterocyclic 1,5,3,7-diazadiphosphacyclooctanes 5a–e. The aliphatic amino acids glycine and -lysine form six-membered heterocyclic 1,3,5-diazaphosphorinanes 6d and 7a–e, respectively, in presence of excess formaldehyde. -lysine differs from glycine by reaction at the terminal amino group. The structures of the compounds have been elucidated by multinuclear NMR spectroscopy. The salts of the phosphino amino acids are soluble in water. Water solubility increases with the number of hydrophilic groups, i.e. free phenols are more soluble than their ethers. Ligand concentrations in water from 0.1 to 1 M were observed.     

Preparative isolation and dual column high-performance liquid chromatography of ginkgolic acids from Ginkgo biloba.

A chromatographic procedure for the preparative isolation of six different 6-alkylsalicylic acids (syn. ginkgolic acids) with as alkyl substituents C13:0, C15:0, C15:1, C17:1, C17:2 and, tentatively C17:3 from Ginkgo biloba leaves was developed. The procedure consisted of a combination of normal-phase, reversed-phase and argentation chromatography. The compounds were characterised by means of UV, ¹H-NMR and ¹³C-NMR spectroscopy, and mass spectrometry after silylation. A 15 cm C₁₈ RP-HPLC column connected in series with a 20 cm silver(I) loaded cation exchanger HPLC column in combination with the solvent methanol–water (93:7) acidified with 0.1% formic acid was capable of separating the ginkgolic acids C13:0, C15:1, C17:2, C15:0 and C17:1 within 21 min on an analytical scale. The separation is based on a combination of reversed-phase mechanisms and double bond complexation. Detection took place by UV at 311 nm. The separation is a good starting point for the development of a quantitative procedure for the five major ginkgolic acids in Ginkgo leaves and standardised extracts.     

反相高效液相色谱法同时测定咖啡豆中的6种酚酸类化合物

建立了同时测定咖啡豆中6种酚酸类化合物(咖啡酸、3-咖啡酰奎尼酸、4-咖啡酰奎尼酸、5-咖啡酰奎尼酸、3,5-二咖啡酰奎尼酸、4,5-二咖啡酰奎尼酸)的反相高效液相色谱测定方法。采用Kromasil C18柱(200 mm×4.6 mm, 5 μm),以乙腈和0.1%甲酸水溶液为流动相进行梯度洗脱,二极管阵列检测器检测,45 min内可对6种目标物进行同时检测,且各化合物都能达到基线分离。经测定,样品中6种酚酸类化合物的加标回收率为90.76%～104.73%,相对标准偏差为0.7%～3.9%。该法简便、快速、灵敏度高,适用于咖啡豆中6种酚酸类化合物的同时分析以及咖啡豆原料与制品的质量控制和综合评价。     

碱催化法衍生化气相色谱/质谱法分析青海湖裸鲤鱼油中的脂肪酸

用碱催化法将青海湖裸鲤鱼油甲酯化,以气相色谱/质谱法分析鱼油中的脂肪酸。青海湖裸鲤可食用部分中鱼油含量为25.13%。从鱼油中共鉴定出47种脂肪酸,包括直链、单支链、多支链饱和脂肪酸,单不饱和、多不饱和脂肪酸,环丙烷基、呋喃基脂肪酸等。不饱和脂肪酸含量为73.6%,其中多不饱和脂肪酸含量为25.4%,以C18∶2(4.9%),C18∶3(3.1%),C20∶4(1.3%),C20∶5(二十碳五烯酸（EPA）, 9.4%)和C22∶6(二十二碳六烯酸（DHA）, 6.7%)为主。单不饱和脂肪酸含量为48.2%,主要由C16∶1(20.3%),C18∶1(25.9%)构成。饱和脂肪酸含量为25.7%,主要有C14∶0(3.4%),C16∶0 (19.4%)和C18∶0(1.1%)。青海湖裸鲤鱼油中还存在不常见的环丙烷基和呋喃基脂肪酸及多种奇数碳链和支链脂肪酸。因此,青海湖裸鲤是功能性脂肪酸的重要膳食来源。     

Preparative isolation and dual column high-performance liquid chromatography of ginkgolic acids from Ginkgo biloba

A chromatographic procedure for the preparative isolation of six different 6-alkylsalicylic acids (syn. ginkgolic acids) with as alkyl substituents C13:0, C15:0, C15:1, C17:1, C17:2 and, tentatively C17:3 from Ginkgo biloba leaves was developed. The procedure consisted of a combination of normal-phase, reversed-phase and argentation chromatography. The compounds were characterised by means of UV, ¹H-NMR and ¹³C-NMR spectroscopy, and mass spectrometry after silylation. A 15 cm C₁₈ RP-HPLC column connected in series with a 20 cm silver(I) loaded cation exchanger HPLC column in combination with the solvent methanol–water (93:7) acidified with 0.1% formic acid was capable of separating the ginkgolic acids C13:0, C15:1, C17:2, C15:0 and C17:1 within 21 min on an analytical scale. The separation is based on a combination of reversed-phase mechanisms and double bond complexation. Detection took place by UV at 311 nm. The separation is a good starting point for the development of a quantitative procedure for the five major ginkgolic acids in Ginkgo leaves and standardised extracts.     

有机膦、胂、(月弟)合钨、钼聚多酸盐的研究(Ⅲ)——邻、间、对硝基苯胂合钼聚多酸盐的合成和鉴定

选取在不同位置上具有一个取代硝基的苯基胂酸,制得了5种新的[(ArAs)_2Mo_6O_(25)H]~(5-)型钼聚多酸盐。报道了它们的光谱及其水溶液中的电化学还原性质。讨论了邻位硝基苯胂合钼聚多酸盐在红外光谱和电化学还原行为中的异常现象。     

液相色谱-质谱联用法测定牛奶中14种青霉素及相应青霉噻唑酸残留量

利用超高效液相色谱-串联质谱法(UPLC-MS/MS)同时测定牛奶中的7种青霉素类抗生素以及7种相应的青霉噻唑酸。样品经乙腈沉淀蛋白,上清液N2吹干后,用水溶解,加入正己烷萃取除去脂肪;提取液经ACQUITY UPLCBEH C18柱分离,乙腈-乙酸铵+甲酸水溶液洗脱。14种物质峰分离良好,定量限范围在5～20μg/kg。在10～50ng/mL质量浓度范围内线性良好,相关系数均大于等于0.999,牛奶中的加标回收率在90%～98%。