6-羟基染料木素和6,8-二羟基染料木素的简便合成

以鹰嘴豆芽素A为原料,通过溴代、甲氧基化和去甲基化三步反应合成了6-羟基染料木素（2b）和6,8-二羟基染料木素（3b）,总产率分别为20%和40%,其结构经¹H NMR, ¹³C NMR, HR-MS（ESI）和IR表征。      

新型含1,2,3-三氮唑的染料木素糖缀合物的合成

以染料木素为起始原料,经两步反应制得中间体7-O-炔丙基染料木素(3);以CuI为催化剂,3与叠氮乙酰基糖经Click反应合成了7-O-［1-(2,3,4,6-四-O-乙酰基-β-D-糖苷)1H-1,2,3-三氮唑-4-甲基］-染料木素(5a~5c); 5a~5c经去乙酰基制得三种含1,2,3-三氮唑的氮苷染料木素糖缀合物(6a~6c)。3, 5和6均为新化合物,其结构经¹H NMR, ¹³C NMR和HR-MS表征。     

染料木素7,4''-二-β-D-吡喃葡萄糖苷的合成

中药槐角为豆料植物槐的果实，富含异黄酮类化合物，主要有槐角苷（Sophoricoside）、槐属双苷（Psophorabioside）、染料木苷（Genistin）、染料木素（Genistein）等。槐角性寒、味苦，归肝、大肠经，有清热泻火、凉血止血的功效，药用历史悠久，是中国药典收载的常用药。研究表明，异黄酮类化合物可能是中药槐角的活性成分之一。目前，对槐角苷、染料木苷及染料木素活性的研究比较多，如已有报道认为槐角苷（即4＇-β-D-吡喃葡萄糖苷）具有明显的降谷丙转氨酶作用；染料木苷及染料木素则具有弱雌激素样活性，表现出良好的抗癌、预防中老年骨质疏松症、女性更年期综合症和心血管疾病等作用。     

小鼠血浆中染料木素水溶性代谢产物和染料木素脂肪酸酯的分离及测定

本文建立了小鼠灌胃染料木素单体后血浆中水溶性染料木素代谢产物和染料木素脂肪酸酯的分离及测定方法。血浆样品经乙酸乙酯萃取后上Sephadex LH-20柱,分别用体积比1∶1的正己烷/氯仿和甲醇洗脱,染料木素脂肪酸酯用脂肪酶酶解后转化成染料木素,水溶性代谢产物用葡萄糖醛酸酶及硫酸酯酶水解成染料木素,然后采用液相色谱串联飞行时间质谱(Q-TOF LC/MS)检测染料木素。血浆中染料木素在10～10000 ng/mL范围内线性关系良好,检测限为1 ng/mL。10批次小鼠血浆中水溶性代谢产物平均为526.006 ng/mL,染料木素脂肪酸酯平均为58.976 ng/mL。采用SephadexLH-20柱具有良好的分离效果,脂肪酶水解染料木素脂肪酸酯稳定、专一性强,用Q-TOF LC/MS检测染料木素快速、灵敏。     

染料木素对骨质疏松性大鼠骨中7种微量元素的影响

目的探讨染料木素对骨质疏松性大鼠骨中微量元素的影响。方法用切除卵巢后引起大鼠骨质疏松的雌性大鼠进行了雌激素尼尔雌醇和染料木素(高、低剂量)的治疗。观察了5组(空白对照组、模型组、染料木素高剂量组、染料木素低剂量、尼尔雌醇组)大鼠股骨中Cu、Mn、Fe、Zn、Pb、Mg和Ca等微量元素的变化。结果统计学结果显示与骨质疏松模型组比较,尼尔雌醇和染料木素能提高去势大鼠骨质中Cu、Fe、Mn、Mg、Ca等元素的含量,尼尔雌醇组中的Zn含量提高,染料木素组中的Zn含量反而下降;尼尔雌醇组与染料木素组中Pb含量下降明显。结论说明染料木素的治疗作用并不是单一的,可以认为中药染料木素是通过发挥对人体整体的调节作用来调节骨骼中微量元素的变化,改变骨质的代谢情况,促进骨密度的提高。     

染料木素氨基甲酸酯类衍生物的合成及生物活性研究

基于多靶点药物设计策略,以染料木素为先导化合物,对其7-位和4’-位羟基进行修饰,合成了24个染料木素氨基甲酸酯类衍生物,其化学结构经1H NMR和HRMS确证.生物活性测试结果表明,部分化合物对乙酰胆碱酯酶具有较强抑制活性,且对H2O2诱导的PC12细胞氧化损伤具有显著保护作用.     

染料木素磺酸钠制备及其抗脂质过氧化作用

染料木素磺酸钠制备及其抗脂质过氧化作用;染料木素;染料木素磺酸钠;水溶性;抗脂质体过氧化     

染料木素分子印迹聚合物的制备及其识别性能

以染料木素为模板分子、4-乙烯基吡啶(4-VP)为功能单体、乙二醇二甲基双丙烯酸酯(EGDMA)为交联剂、四氢呋喃(THF)为溶剂,采用本体聚合法制备了染料木素的分子印迹聚合物;采用静态平衡结合实验研究了该分子印迹聚合物对染料木素的结合能力和选择性能.结果表明,与化学组成相同的相应非印迹聚合物相比,染料木素分子印迹聚合物对染料木素的吸附性能和选择性更好.利用所合成的分子印迹聚合物作为固相萃取材料填充固相萃取小柱,可以选择性地从豆奶粉中分离、富集染料木素;此外,该分子印迹聚合物还有望用于其他豆制品的分析检验.     

薄层扫描法测定槐角及槐角丸中的染料木苷和总染料木素

在硅胶G薄层色谱板上,采用双波长薄层扫描法建立了测定槐角、槐角丸中的染料木苷和总染料木素的分析方法。染料木苷和染料木素的薄层展开剂分别为V(三氯甲烷)∶V(甲醇)∶V(冰乙酸)=25∶7∶4和V(三氯甲烷)∶V(甲醇)∶V(冰乙酸)=15∶1∶0.1,染料木苷和染料木素分别在0.5～3.0μg和0.9～5.0μg范围内呈良好线性。该方法为中药槐角和中成药槐角丸的质量控制提供检测方法。     

薄层扫描法测定槐角及槐角丸中染料木苷和总染料木素的含量

槐角(Fructus Sophorae)为豆科植物的干燥成熟果实,冬天采收,有人工栽培和野生,全国大部分地区有生产.槐角丸是由槐角、黄芩、枳壳、防风、当归、地榆组成的常用中成药,具有清肠疏风、凉血止血的功效.槐角在处方中是君药,而染料木素、染料木苷为槐角的主要成分,具有极强的抗癌活性、抗繁殖性、抗氧化性、抗菌和消炎作用.关于槐角丸的有效成分测定方法主要有紫外分光光度法测总黄酮,薄层色谱法测定芦丁和黄芩苷,高效液相色谱测定黄芩苷和测定染料木素.本文在硅胶G薄层色谱板上,采用双波长薄层扫描法建立了测定槐角、槐角丸中的染料木苷和总染料木素的分析方法.染料木苷和染料木素的薄层展开剂分别为三氯甲烷-甲醇-冰醋酸(2574)和三氯甲烷-甲醇-冰醋酸(1510.1),染料木苷和染料木素分别在0.5～3.0 μg和0.9～5.0μg范围内呈良好线性.该方法快速、简便,为中药槐角和中成药槐角丸的质量控制提供科学依据.     

Liquid chromatography/electrospray ionization mass spectrometry for the characterization of twenty-three flavonoids in the extract of Dalbergia odorifera

A method incorporating high-performance liquid chromatography (HPLC) with electrospray ionization and tandem mass spectrometry, with parallel analysis by HPLC with UV detection using a diode-array detector, was developed for the qualitative characterization of flavonoids in D. odorifera. Twenty-three flavonoids, including six isoflavones, six neoflavones, four isoflavanones, three flavanones, two chalcones, one isoflavanonol and one pterocarpan, were unambiguously identified by comparing their retention times, UV and MS spectra with those of authentic compounds. Furthermore, the collision-induced dissociations of the [M-H]- ions were studied to clarify the MS behavior of the different types of flavonoids. In negative ion ESI-MS all the flavonoids yielded prominent [M-H]- ions in the first order mass spectra. Fragments involving losses of CH3*, H2O, CO, C2H2O, and CO2 were observed in the MS/MS spectra. Each of the seven types of flavonoid showed characteristic MS/MS fragmentation patterns. The isoflavanones, flavanones and chalcones were observed to undergo retro-Diels-Alder fragmentations. The spectra of almost all the neoflavonoids unexpectedly exhibited only [M-H-CH3]-* radical anions as base peaks without any further fragmentation. Substitution positions also remarkably influenced the fragmentation behavior, which could assist in distinction among the flavonoid isomers. The fragmentation rules deduced here could aid in the characterization of other flavonoids of these types.     

Identification of phenolic constituents in Radix Salvia miltiorrhizae by liquid chromatography/electrospray ionization mass spectrometry

The phenolic components from Radix Salvia miltiorrhizae Bunge, a well-known herbal medicine (Dan-Shen in Chinese), have been investigated by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC/ESI-MS/MS). HPLC analyses were performed on a reversed-phase C18 column using gradient elution. In the ESI mass spectra a predominant [M-H]- ion was observed in negative mode and provided molecular mass information. ESI-MS/MS spectra of the [M-H]- ions were used for structural analysis, based on the spectra of standards. It was found that caffeic acid and its monomeric analogs containing a carboxyl group readily lost CO2, while dimers, trimers and tetramers of caffeic acid expelled successively danshensu or caffeic acid or their esters. Twenty-eight phenolic compounds in S. miltiorrhizae were characterized, of which eight compounds were positively identified by comparison with standards. The remaining twenty phenolics for which standards were not available were tentatively identified based on their UV spectra and MS/MS fragmentation characteristics.     

Screening non-colored phenolics in red wines using liquid chromatography/ultraviolet and mass spectrometry/mass spectrometry libraries

Liquid chromatography/ultraviolet (LC/UV) and mass spectrometry/mass spectrometry (MS/MS) libraries containing 39 phenolic compounds were established by coupling a LC and an ion trap MS with an electrospray ionization (ESI) source, operated in negative ion mode. As a result, the deprotonated [M-H]- molecule was observed for all the analyzed compounds. Using MS/MS hydroxybenzoic acid and hydroxycinnamic acids showed a loss of CO2 and production of a [M-H-44]- fragment and as expected, the UV spectra of these two compounds were affected by their chemical structures. For flavonol and flavonol glycosides, the spectra of their glycosides and aglycones produced deprotonated [M-H]- and [A-H]- species, respectively, and their UV spectra each presented two major absorption peaks. The UV spectra and MS/MS data of flavan-3-ols and stilbenes were also investigated. Using the optimized LC/MS/MS analytical conditions, the phenolic extracts from six representative wine samples were analyzed and 31 phenolic compounds were detected, 26 of which were identified by searching the LC/UV and MS/MS libraries. Finally, the presence of phenolic compounds was confirmed in different wine samples using the LC/UV and LC/MS/MS libraries.     

A non-covalent dimer formed in electrospray ionisation mass spectrometry behaving as a precursor for fragmentations

A non-covalent-bonded dimer was detected in the positive ion electrospray ionisation (ESI) mass spectra of a synthetic impurity. In tandem mass spectrometry (MS/MS) experiments using collision-induced dissociation (CID), the ion was found to behave as a [M+H]+-type precursor ion for fragmentation until MS5. The dimer was probably formed through multi-hydrogen bonds over a proton bridge. When the fragmentation occurred at the center of the bridge, the dimer was broken apart to give monomer fragments at MS6. However, no corresponding deprotonated dimer [2M-H]- was found in the negative ion ESI spectra. The dimer was extremely stable, and it could still be observed when a fragmentation voltage of up to 50 V was applied in the ionisation source. The formation of the non-covalent dimer was also found to be instrument-dependent, but independent of sample concentration. Accurate mass measurements of the [2M+H]+ and [M+H]+ ions, and their MSn product ions, provided the basis for assessing the fragmentation mechanism proposed for [2M+H]+. The fragmentation pathway was also illustrated for the deprotonated molecule [M-H]-.     

Studies on Fragmentation Pathways of N-Ethoxy （phenyl） phosphoryl Amino Acids by Electrospray Ionization Tandem Mass Spectrometry

IntroductionPhosphorylation often acts as a molecular switchcontrolling the protein activity in different pathways asin metabolism,signal transduction,cell division,andso on.Therefore,N-phosphoryl amino acids play aspecial and important role in biological…     

Generation of alkoxide anions from a series of aliphatic diols and alcohols and their ion-molecule reactions with carbon dioxide in the gas phase

Alkoxide anions, [M-H](-) from a series of aliphatic diols and alcohols are generated in the source under negative ion electrospray ionisation conditions by cone-voltage fragmentation of the corresponding [M + F](-) ions. The collision-induced dissociation (CID) spectra of [M-H](-) ions consist of [M-H-2H](-) ions, in addition to the other characteristic fragment ions, and the relative abundance of [M-H-2H(-) ions among the series of diols varies as a function of chain length that could be explained based on their stabilities through intramolecular hydrogen bonding. The reactivity of alkoxide anions is studied through ion-molecule reactions with CO(2) in the collision cell of a triple quadrupole mass spectrometer. All the alkoxide anions reacted with CO(2) and formed corresponding carbonate anions, [M-H + CO(2)](-) ions. The reactivity of alkoxide anions within the series of diols also reflected the stability of their [M-H](-) ions.     

Characterization of alpha- and gamma-glutamyl dipeptides by negative ion collision-induced dissociation

The low-energy CID mass spectra of the [M-H](-) ions of a variety of dipeptides containing glutamic acid have been obtained using cone-voltage collisional activation. Dipeptides with the gamma-linkage, H-Glu(Xxx-OH)-OH, are readily distinguished from those with the alpha-linkage, H-Glu-Xxx-OH, by the much more prominent elimination of H-Xxx-OH from the [M-H](-) ions of the former isomers, resulting in formation of m/z 128, presumably deprotonated pyroglutamic acid. Dipeptides with the reverse linkage, H-Xxx-Glu-OH, show distinctive fragmentation reactions of the [M-H](-) ions including enhanced elimination of CO(2) and formation of deprotonated glutamic acid. Exchange of the labile hydrogens for deuterium has shown that there is considerable interchange of C-bonded hydrogens with labile (N- and O-bonded) hydrogens prior to most fragmentation reactions. All dipeptides show loss of H(2)O from [M-H](-). MS(3) studies show that the [M-H-H(2)O](-) ion derived from H-Glu-Gly-OH has the structure of deprotonated pyroglutamylglycine while the [M-H-H(2)O](-) ions derived from H-Glu(Gly-OH)-OH and H-Gly-Glu-OH show a different fragmentation behaviour indicating distinct structures for the fragment ions.     

Use of solid-phase extraction, reverse osmosis and vacuum distillation for recovery of aromatic sulfonic acids from aquatic environment followed by their determination using liquid chromatography-electrospray ionization tandem mass spectrometry

Three different sample preparation techniques (i) solid-phase extraction, (ii) reverse osmosis and (iii) vacuum distillation have been investigated and the recoveries were compared for determination of highly water-soluble benzene and stilbene sulfonic acids in aqueous environment by liquid chromatography with photodiode array (PDA) and electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). The recoveries were quite high using vacuum distillation (>90%) compared to solid phase extraction and reverse osmosis. The negative ion ESI mass spectra containing the peaks of quasimolecular ion [M-H]- allow the molecular mass determination of unknown compounds whereas the structures were proposed using fragments obtained from MS/MS analysis of [M-H]- ions. At lower fragmentation voltages only the quasimolecular ion [M-H]- was observed and as fragmentation voltages increased, it led to the formation of fragment ions corresponding to [M-H-SO3]-, [M-H-SO2]-, and SO3-. The detection limits were 1-28 microg/L with LC-ESI-MS. The sample collected from wastewater treatment plant was found to contain 21.1, 13.3, 12.1, 41.8 and 9.9 microg/L of cis-4,4(l)-diaminostilbene-2,2(l)-disulfonic acid (cis-DASDA), trans-4,4(l)-diaminostilbene-2,2(l)-disulfonic acid (trans-DASDA), 3-amino acetanilide-4-sulfonic acid (3-AASA), 4-chloroaniline-2-sulfonic acid (4-CASA), 2-chloroaniline-5-sulfonic acid (2-CASA), respectively.     

Tandem mass spectrometric analysis of glyphosate,glufosinate, aminomethylphosphonic acid and methylphosphinicopropionic acid

A detailed MS(n) study of glyphosate, glufosinate and their main metabolites, aminomethylphosphonic acid and methylphosphinicopropionic acid, using an ion trap mass spectrometer, was performed. The analytes show good response in negative ion electrospray mass spectrometry (ES-MS) as [M-H](-) ions. Tandem-MS spectra reveal a wealth of structurally specific ions, allowing characterisation of the fragmentation pathways of the four analytes in their native form for the first time. The ions formed at each stage of fragmentation reveal ions common to each analyte, such as phosphinate, as well as analyte specific transitions. Simplex optimisation allows optimum trapping and fragmentation parameters to be determined leading to improved response for particular transitions and transition sequences, and revealing previously unseen ions.     

Electrospray ionization mass spectrometry for analysis of low-molecular-weight anticancer drugs and their analogues

In this study, several anticancer drugs and their analogues consisting of organic and organometallic compounds were analyzed by electrospray ionization mass spectrometry (ESI/MS) using a quadrupole mass spectrometer. Protonated molecular ions [M+H]⁺ were observed for all of the compounds studied, and in the case of the two steroid sulfates, deprotonated molecular ions [M-H]^? were obtained. Tandem mass spectrometry was performed on these quasimolecular ions, and the product ions formed provided useful fragmentation patterns that were characteristic for the compounds. This study provides evidence that ESI/MS is a sensitive technique for structure confirmation and identification of small organic and organometallic molecules.