辅酶Q_(10)的应用概况与合成进展

辅酶Ｑ１０是一种具有应用价值的药物,过去几十年内已报导大量合成辅酶Ｑ１０的方法,作者综述了辅酶Ｑ１０应用与合成进展。     

双（1,2—丙二胺）合铜的TCNQ盐的合成与光谱研究

合成了导电性ＴＣＮＱ盐Ｃｕ（ｐｎ）２（ＴＣＮＱ）ｎ（ｎ＝２和３，ｐｎ＝１，２－丙二胺，ＴＣＮＱ＝７，７，８，８－四氰基对苯二醌二甲烷）。红外光谱、电子光谱和Ｘ－光电子能谱研究表明ＴＣＮＱ盐中存在ＴＣＮＱ°和ＴＣＮＱ－，ＴＣＮＱ°与ＴＣＮＱ－之间发生了部分电子转移，致使铜呈混合价态。它们的粉末室温电导率为１．１×１０－５～２．４×１０－６ｏｈｍ－１ｃｍ－１。     

水杨醛缩—5—碘—5—氨基喹啉的合成及荧光光度法测定煤渣中痕量镓的研究

报道了新息夫碱试剂水杨醛缩－５－碘－５－氨基喹啉（ＳＡＩＡＱ）的合成。用元素分析、红外光谱法确定了其结构。测定了ＳＡＩＡＱ的酸度常数Ｋａ１＝２．４０×１０＾－４，Ｋａ２＝２．９８×１０＾－９。在ｐＨ３．５０￣５．００范围内ＳＡＩＡＱ与Ｇａ＾３＋形成稳定的荧光螯合物，且在λｅｘ／λｅｍ＝４２８ｎｍ／５４０ｎｍ产生强烈荧光。其荧光强度与Ｇａ＾３＋的浓度在１．５μｇ／Ｌ￣２６０μｇ／Ｌ范围内呈线性关系，     

辅酶Q9的合成

以辅酶Q0为起始原料,经Diels-Aider加成,缩合和逆Dicls-Alder分解反应,合成了辅酶Q10的类似物辅酶Q9,总收率61.9%.中间体和Q9的结构经1H NMR和EI-MS表征.     

Δ6 去饱和酶催化合成γ-亚麻酸

报道了含△６去饱和酶的深黄被孢霉菌丝提取物催化亚油酸合成γ－亚麻酸．研究了辅酶、温度、时间等对γ－亚麻酸合成的影响．结果表明,反应温度降低,γ－亚麻酸的产率提高．在１０℃以下．γ－亚麻酸的产率达到最大值;苹果酸盐对该反应有明显促进作用．γ－亚麻酸的产率随体系ｐＨ增加而增加,且在ｐＨ＝７~８时产率较高;该反应需在分子氧存在下进行;ＮＡＤＰＨ,ＡＴＰ和ＣｏＡ是该反应的必需辅酶．在优化的反应条件下,γ－亚麻酸的产量达到０．２１ｍｇ/ｍＬ。     

1—甲氧基—1,3,5（10）,11—四烯—9—酮7αH—15—降桉烷的简便合成

报道了１－甲氧基－１，３，５（１０），１１－四烯－９－酮７αＨ－１５－降桉烷的简便合成，其关键步骤是４，１１－二烯－３，９－二酮－１４－降桉烷的ＤＤＱ重排脱氢反应。     

水杨醛缩-5-碘-8-氨基喹啉的合成及荧光光度法测定煤渣中痕量镓的研究

报道了新息夫碱试剂水杨醛缩－５－碘－８－氨基喹啉（ＳＡＩＡＱ）的合成。用元素分析、红外光谱法确定了其结构。测定了ＳＡＩＡＱ的酸度常数Ｋａ１＝２．４０×１０－４，Ｋａ２＝２．９８×１０－９。在ｐＨ３．５０～５．００范围内ＳＡＩＡＱ与Ｇａ３＋形成稳定的荧光螯合物，且在λｅｘ／λｅｍ＝４２８ｎｍ／５４０ｎｍ产生强烈荧光。其荧光强度与Ｇａ３＋的浓度在１．５μｇ／Ｌ～２６０μｇ／Ｌ范围内呈线性关系，检出限１．５μｇ／Ｌ，考察了共存离子的影响，选择性高。已应用于煤渣中痕量镓的分析。     

NAD－硅胶亲和色谱固定相的合成和在核苷酸及其碱基分析中的应用

ＮＡＤ－硅胶亲和色谱固定相的合成和在核苷酸及其碱基分析中的应用于世林，苗凤琴，杨朝霞，冯茹（北京化工大学应用化学系，北京，１０００２９）关键词烟酰胺腺嘌呤二核苷酸（ＮＡＤ），亲和色谱，核苷酸烟酰胺腺嘌呤二核苷酸（ＮＡＤ，辅酶Ⅰ）是多种脱氢酶的辅酶，通...     

四氰基醌二甲烷修饰碳糊电极催化氧化测定多巴胺

以四氰基醌二甲烷（ＴＣＮＱ）作介体,制成ＴＣＮＱ修饰碳糊电极。研究该电极的性能。该电极对多巴胺（ＤＡ）有良好的电催化氧化作用,在ＤＡ浓度６．７５×１０＾－５－６．７５×１０＾－３ｍｏｌ·Ｌ＾－１内。催化电流与ＤＡ浓度呈线性关系,响应时间小于１０ｓ。该电极用于针剂中多巴胺测量,结果较好。     

Baeyer-Villiger单加氧酶在有机合成中的应用

综述了Baeyer-Villiger单加氧酶在有机合成中的应用.较之传统的化学反应, 氧化酶催化剂反应有较好的选择性、可控性和经济性. 环己酮加氧酶是一种还原型辅酶I (NADPH)依赖型氧化酶, 是最早被报道能够催化Baeyer-Villiger氧化的酶. 这些重要反应产生了合成化学家很感兴趣的扩环产物. 环己酮加氧酶也是有用的生物催化剂, 由于辅酶再生的问题已被工程菌克服了, 所以能像全细胞催化剂那样使用. 对酮包括杂环酮进行Baeyer-Villiger氧化和动态动力学拆分, 放大这种反应作为合成路线是很有前途的.     

Validation and application of an HPLC-EC method for analysis of coenzyme Q10 in blood platelets

Previous studies have indicated that analysis of coenzyme Q10 (CoQ10) in platelets may be clinically useful. The study objectives are to describe, validate and provide application of an HPLC-EC method for platelet CoQ10 analysis. This method analyzes oxidized (ubiquinone-10) and reduced (ubiquinol-10) forms of CoQ10 using two separate injections with the electrochemical analytical cell set at neutral and oxidizing potentials. Results showed that chromatograms were free of interfering peaks. Calibration curves were constructed over a concentration range 116-2317 nmol/L (r(2) = 0.99). The extraction recovery was >95%. The within-run precision CV% was < or =4.2%, and the day-to-day precision was < or =9.9%. Platelets were isolated by differential centrifugation, and frozen at -70 degrees C until analysis. The application of the method was used to compare accumulation of CoQ10 in platelets vs plasma in eight adult volunteers during a 28 day supplementation period (5 mg/kg/day of ubiquinol-10). Mean platelet total CoQ10 was 164 pmol/10(9) cells, and ubiquinol-10:total CoQ10 ratio was 0.56. During supplementation platelet CoQ10 levels were more consistent and predictable than plasma CoQ10 levels. The results indicate that this validated method for platelet ubiquinol-10 and ubiquinone-10 analysis is acceptable for use in the clinical laboratory, and that platelet CoQ10 may have important advantages over plasma during CoQ10 supplementation.     

Determination of ubidecarenone (coenzyme Q10, ubiquinol-10) in raw materials and dietary supplements by high-performance liquid chromatography with ultraviolet detection: single-laboratory validation

A method based on high-performance liquid chromatography with ultraviolet detection has been developed to quantify ubidecarenone [coenzyme Q10 (CoQ10)] in raw materials and dietary supplements. Single-laboratory validation has been performed on the method to determine repeatability, accuracy, selectivity, limits of detection and quantification (LOQ), ruggedness, and linearity for CoQ10. As CoQ10 can exist as the biologically active reduced form, the application of an oxidizing agent, ferric chloride, drives the equilibrium mechanics to the fully oxidized state and allows for exact quantification of total CoQ10 in the sample. This method was found to be fit and linear for the testing of materials containing CoQ10 in the range of approximately equal 50-1000 mg/g. Repeatability precision for CoQ10 was between 2.15 and 5.00% relative standard deviation. Observed recovery of CoQ10 was found to be between 93.8 and 100.9%. LOQ was found to be 9 microg/mL. Further, limited studies showed that some adulterants and degraded material could be satisfactorily separated from CoQ10 and identified.     

Effect of coenzyme Q(10) incorporation on the characteristics of nanoliposomes

Coenzyme Q(10) (CoQ(10)) is incorporated in nanoliposomes composed of egg yolk phospholipid, cholesterol, and Tween 80. Atomic force microscopy, performed to characterize vesicle surface topology, shows some visible influence of CoQ(10) on the nanoliposomal structure. CoQ(10) incorporation can suppress the increase of the z-average diameter of nanoliposomes during storage for 8 months at 4 degrees C. The liposomal lipid peroxidation caused by Fe(III)/ascorbate is also significantly inhibited. Perturbation of acyl chain motion of lipids due to the presence of CoQ(10) in the bilayer is examined by fluorescence probe diphenyl-hexatriene and Raman spectroscopy. Fluorescence probe studies indicate that CoQ(10) incorporation results in the microviscosity increase of nanoliposomes. The steric structure of nanoliposomes reflected by Raman spectroscopy changes obviously and shows CoQ(10) content dependency. The order parameters for the lateral interaction between chains increase. The trans conformation decrease and the gauche conformation increase as the weight contents of CoQ(10) incorporation are at 1%, 5%, 10%, and 32.5%. However, the order parameters for the longitudinal interaction in chains was higher than that of pure nanoliposomes as the weight content of CoQ(10) is at 25%. Results suggest that CoQ(10)might intercalate between lipid molecules and perturb the bilayer structure.     

Pseudorotaxane-like supramolecular complex of coenzyme Q10 with gamma-cyclodextrin formed by solubility method

The purpose of this study is to reveal whether Coenzyme Q10 (CoQ10) forms pseudorotaxane-like supramolecular complex with gamma-cyclodextrin (gamma-CyD). The poorly soluble complex of CoQ10 with gamma-CyD in water was prepared by the solubility method. The X-ray diffraction pattern of the CoQ10/gamma-CyD complex was different from that of the physical mixture, but almost the same as that of polypropylene glycol (PPG)/gamma-CyD polypseudorotaxane. Also, the differential scanning calorimetrical study and FT-IR study demonstrated the interaction between CoQ10 and gamma-CyD in the solid state. The 1H-NMR study and the yield study of the supramolecular complex of CoQ10 with gamma-CyD demonstrated that the stoichiometry was 5 : 1 (gamma-CyD : CoQ10). The dispersion rate of CoQ10 was markedly increased by the formation of the supramolecular complex with gamma-CyD, possibly due to submicron-ordered particle formulation. In fact, CoQ10 was found to form submicron-sized supramolecular particles with gamma-CyD, when prepared by the solubility method. Consequently, the present study showed that CoQ10 forms the pseudorotaxane-like supramolecular complex with gamma-CyD in water.     

Determination of coenzyme Q10 in human breast milk by high-performance liquid chromatography

An isocratic HPLC method was developed for the determination of coenzyme Q(10) (CoQ(10)) in human breast milk. After a single-step liquid-liquid extraction, the milk extract was injected directly into the HPLC system. The analytical method is based on pre-column inline treatment of CoQ(10). Chromatographic separation of CoQ(10) and coenzyme Q(9) (CoQ(9)) internal standard was achieved using a reversed-phase Microsorb-MV C(18) analytical column. CoQ(10) and CoQ(9) were monitored by an electrochemical detector (ECD). An excellent linearity (r = 0.999) was observed for CoQ(10) in the concentration range 0.06-2.5 micromol L(-1) in breast milk. The limit of quantitation (LOQ) was 60 nmol L(-1). Coefficients of variations (CVs) for intra-day and inter-day assay precisions were less than 5%. A total of 194 breast milk samples were analyzed for the CoQ(10) concentration; the mean value was 0.32 +/- 0.21 micromol L(-1).     

Determination of coenzyme Q10 content in raw materials and dietary supplements by high-performance liquid chromatography-UV: collaborative study

An international collaborative study was conducted of a high-performance liquid chromatographic (HPLC)-UV method for the determination of coenzyme Q10 (CoQ10, ubidecarenone) in raw materials and dietary supplements. Ten collaborating laboratories determined the total CoQ10 content in 8 blind duplicate samples. Sample materials included CoQ10 raw material and 4 finished product dietary supplements representing softgels, hardshell gelatin capsules, and chewable wafers. In addition, collaborating laboratories received a negative control and negative control spiked with CoQ10 at low and high levels to determine recovery. Materials were extracted with an acetonitrile-tetrahydrofuran-water mixture. Ferric chloride was added to the test solutions to ensure all CoQ10 was in the oxidized form. The HPLC analyses were performed on a C18 column using UV detection at 275 nm. Repeatability relative standard deviations (RSDr) ranged from 0.94 to 5.05%. Reproducibility relative standard deviations (RSDR) ranged from 3.08 to 17.1%, with HorRat values ranging from 1.26 to 5.17. Recoveries ranged from 74.0 to 115%. Based on these results, the method is recommended for Official First Action for determination of CoQ10 in raw materials and dietary supplement finished products containing CoQ10 at a concentration of >100 mg CoQ10/g test material.     

Determination of coenzyme Q10 in human seminal plasma by high-performance liquid chromatography and its clinical application

A high-performance liquid chromatographic (HPLC) method for the analysis of coenzyme Q10 (CoQ10) in human seminal plasma was developed and applied to investigate its clinical significance as a reference index relating to oxidative stress and infertile status of spermatozoa. After precipitation of proteins in seminal plasma with methanol, CoQ10 and coenzyme Q9 (CoQ9; internal standard) were extracted with hexane. The supernatant after centrifugation was evaporated to dryness with nitrogen at 45 degrees C. The residue was re-dissolved in isopropanol. HPLC separation of the sample solution was performed on a Lichrospher C(18) column with a mobile phase composed of isopropanol-methanol-tetrahydrofuran in the ratio of 55:39:6 (v/v/v) at a flow rate of 1.0 mL/min. Under the chromatographic conditions described, the CoQ10 and CoQ9 had retention times of approximately 5.83 and 4.97 min, respectively. The peaks were detected at UV 275 nm. Good separation and detectability of CoQ10 in human seminal plasma were obtained. The method was linear in the range 0.01-10.00 microg/mL. The relative standard deviations within- and between-assay for CoQ10 analysis were 0.85 and 1.86%, respectively. The average recoveries were 94.1-99.0% for the human seminal plasma samples. The CoQ10 levels in seminal plasma of 195 patients and 23 control subjects were studied. CoQ10 concentrations in the two populations were: 37.1 +/- 12.2 ng/mL in the fertile group and 48.5 +/- 20.4 ng/mL in the infertile group. The large difference (p < 0.01) between the fertile and infertile populations is evident.     

High-performance liquid chromatography of coenzyme Q-related compounds and its application to biological materials

A convenient and precise method for the separation and determination of coenzyme Q (CoQ)-related compounds (CoQ homologues, plastoquinone-9, ubichromenol-9, etc.) was developed using high-performance liquid chromatography (HPLC). All compounds tested were separated using a reverse-phase column with a suitable mobile phase and detected at a wavelength of 275 nm. CoQ extracts in plasma and erythrocytes were purified by thin-layer chromatography prior to HPLC analysis, but such purification was not necessary when determining CoQ in urine and tissues. Hydroquinone forms of CoQ existing in animal tissues were oxidized to the corresponding quinone forms with potassium hexacyanoferrate(III). This HPLC method was applied satisfactorily to the determination of the contents of CoQ homologues in human and animal samples. CoQ10 was the only homologue detected in human samples, and CoQ8, CoQ9 and CoQ10 were native homologues of CoQ in rat tissues. Ubichromenol-9 and plastoquinone-9 were not detected in these samples.     

A rapid and sensitive LC-MS/MS method for determination of coenzyme Q10 in tobacco (Nicotiana tabacum L.) leaves

A rapid and sensitive liquid chromatography-tandem mass spectrometry method with multiple reaction monitoring has been proposed for the analysis of coenzyme Q10 in (CoQ10) tobacco leaves. The method used electrospray ionization with detection in positive ion mode. Sample pretreatment involved ultrasonic extraction of fresh tobacco leaves with anhydrous ethanol for 15 min and followed by extraction of the supernatant with hexane. The separation of CoQ10 was performed on a Symmetry Shield RP18 column with a mixture of acetonitrile and isopropanol (8:7, v/v) containing 0.5% formic acid as mobile phase. Quantification of CoQ10 was performed by the standard addition method. The limit of detection and limit of quantitation of CoQ10 were, respectively, 1.2 ng/mL (S/N = 3) and 4.0 ng/mL (S/N = 10). The relative standard deviations of peak area were 0.91% and 1.21% for intra-day and inter-day, respectively. The recoveries of CoQ10 ranged from 98.2 to 99.3% and the corresponding RSDs were less than 2.4%. Analysis took 5 min, making the method suitable for rapid determination of CoQ10 in tobacco leaves. The proposed method has been successfully applied to the analysis of CoQ10 in the leaves from eight varieties of tobacco.     

Inclusion Complexes of Coenzyme Q10 with Polyamine‐Modified β‐Cyclodextrins: Characterization,Solubilization, and Inclusion Mode

The inclusion‐complexation behavior of coenzyme Q10 (CoQ10) with the three polyamine‐modified β‐cyclodextrins (CDs) 1 – 3 was investigated in both solution and the solid state by means of NMR, XRD, and FT‐IR spectroscopy. The results showed that the apparent solubility of CoQ10 increased linearly upon addition of hosts 1 – 3 , giving A_L‐type phase‐solubility curves. These hosts 1 – 3 were able to solubilize CoQ10 to high levels, up to 1.35, 1.52, and 1.44 mg/ml (calculated as CoQ10), respectively. The host 2 with a moderate‐length chain is the most suitable for inclusion complexation of CoQ10. Accroding to the ROESY experiments, the MeO groups of CoQ10 and the tether of 2 can be co‐included into the cavity of β‐CD through the induced‐fit interaction between host and guest. The binding ability of modified β‐CDs 1 – 3 upon complexation with CoQ10 are discussed from the viewpoints of the size/shape‐matching relationship and the induced‐fit concept between host CDs and guest CoQ10 molecule.