Simultaneous determination of NSO-heterocycles, homocycles and their metabolites in groundwater of tar oil contaminated sites using LC with diode array UV and fluorescence detection

For monitoring groundwater at tar oil contaminated sites a simple method of analysis was developed for the simultaneous detection of several NSO heterocyclic compounds, homocyclic compounds, mobile two- and three-cyclic PAHs and selected metabolites. The groundwater samples are enriched using SPE with polymer material at pH 4. Chromatographic separation and detection is performed by LC with diode array UV or fluorescence detection. The recoveries of 25 selected compounds were mostly between 80-110% and the detection limits were 0.4-2.4 microg/L for UV detection and for the fluorescence detectable compounds 0.4-140 ng/L. The method was successfully applied to groundwater samples from a wood preserving facility. Especially benzo(b)thiophene showed an increasing dominance downgradient of the source. Detection of metabolites, such as 1-hydroxyiso-, 2-hydroxyquinoline and 2-hydroxy-4-methylquinoline, 2-naphthoic acid, and 1-indanone, indicating in situ biodegradation, was confirmed by LC-ESI-MS analysis.     

Fluorescence of zirconium-naphthalene complexes: effect of ortho-naphthalene substitution

The effect of the position of substituents on the formation of metal-naphthalene complexes has been investigated. Two positional isomers, 1-hydroxy-2-naphthoic acid (1H2NA) and 3-hydroxy-2-naphthoic acid (3H2NA), have been chosen. A comparative study of the luminescence behaviour of the two isomers in the presence of Zr(IV) has been performed. Interesting results were obtained. While 1-hydroxy-2-naphthoic acid is quenched in the presence of Zr(IV), 3-hydroxy-2-naphthoic acid produced high-fluorescence enhancement. Several pH studies were performed between pH 2.5 and 5.0 and the stoichiometries of the complexes were also established at the different pH values tested, by use of the Benesi-Hildebrand method. In addition, the formation constants have been calculated. Finally, quenching and lifetime studies were performed in an attempt to establish the type of quenching (static or dynamic) that is produced when a complex is formed between 1-hydroxy-2-naphthoic acid and zirconium metal ion.     

N.m.r. studies on aromatic compounds. I—13C n.m.r. spectra of some mono- and disulpho-substituted hydroxycarboxylic acids

Carbon-13 n.m.r. spectra of 3-hydroxy-4-sulpho-2-naphthoic, 3-hydroxy-5-sulpho-2-naphthoic, 3-hydroxy-7-sulpho-2-naphthoic, 5-sulphosalicylic, 3-hydroxy-5,7-disulpho-2-naphthoic, 1-hydroxy-4,7-disulpho-2-naphthoic, and 3,5-disulphosalicylic acids were recorded with and without proton noise-decoupling. Analyses of the spectra were carried out for all compounds except 3-hydroxy-5-sulpho-2-naphthoic acid which dimerized. The fine splitting caused by long-range coupling was used in identifying the lines of the ¹³C n.m.r. spectra.     

Synthesis of 4-oxo-1,3-benz- and naphthoxazinium salts from o-hydroxyarylamides

The acid-catalyzed acylation of primary and secondary o-hydroxyarylamides, the probable reaction scheme, and the possibility of the formation of 4-oxo-1,3-arenooxazinium salts and analogs in the reaction of amides of salicylic, coumaric, and 1-hydroxy- and 3-hydroxynaphthoic acids and their N-alkyl(aryl)derivatives with excess amounts of aliphatic acid anhydrides and 70% perchloric acid, as well as by the acid cyclization of O- and N-mono- and diacyl derivatives of these amides, are examined. Twelve previously unknown 2-alkyl- and 2-styryl-4-oxo-1,3-naphth[3,2-e]-and -[1,2-e]oxazinium perchlorates were synthesized. N-Methyl- and N-benzylamides of 8-acetoxy-1-naphthoic acid are formed instead of the expected peri-cyclic analogs of oxazinium salts in the reaction of 8-hydroxy-1-naphthoic acid anilides with acetic anhydride and perchloric acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1611–1616, December, 1979.Original article submitted May 31, 1978; revision submitted April 2, 1979.     

钝化萘衍生物的磺化反应研究

研究了带吸电子取代基的一系列钝化萘衍生物与SO~3进行的磺化反应, 用^1H NMR分析反应混合物的组成.1-萘磺酸以71:20:9的比例产生1,5-, 1,6-和1,7-萘二磺酸, 进一步磺化得到1,3,5-, 1,3,6-萘三磺酸和1,3,5,7-萘四磺酸. 1-萘甲醛的单硫化得到比例为55:9:6:30的5-, 6-,7-和8-磺酸取代物. 1-苯甲酮萘则以83:11:6的比例得到5-,6-,和7-磺酸取代物. 1-硝基萘仅得到5位磺化产物. 1-萘甲酸和1-萘甲酸甲酯得到5位和8位取代产物. 所有的2位取代萘衍生物均先得到5和8位取代产物. 提出了生成SO~3络合物及迫位磺化的历程.     

On-line solid-phase extraction with on-support derivatization for high-sensitivity liquid chromatography tandem mass spectrometry of estrogens in influent/effluent of wastewater treatment plants

A solid-phase extraction coupled to liquid chromatography/tandem mass spectrometry for the determination of estrogens in sewage influent and effluent has been performed. The possibility of preparing estrogen derivatives directly on a solid-phase extraction bed in which the targeted analytes have been previously isolated and pre-concentrated was explored. This method uses an Oasis HLB column (2.1 mm x 20 mm i.d.) for on-line sample cleanup and derivatization support, and a Sunfire C(18) column (150 mm x 2.1 mm i.d.) with a mobile phase consisting of acetonitrile-water-formic acid for separation. After sample introduction, some matrix interferences are removed by washing up SPE column with methanol-water. Phenolic hydroxyl group of estrogens is subsequently derivatized with dansyl chloride. Reaction takes place in the on-line solid-phase extraction column. The excess of reagent and other matrix interferences are then removed by a second washing. Dansylated estrogens are further back eluted and analyzed with HPLC-MS-MS. The optimized on-line protocol is emphasized owing to a low limit of quantification (1 ng L(-1)) is achieved with only around 1 mL of sample and a low sensitive MS instrument. Developed strategy has been demonstrated to be an improvement over existing methods due to its greater sensitivity and the low volume of matrix used and the total analysis time (extraction, derivatization, analysis) is less than 17 min.     

New metallochromic indicators for compleximetric titration of calcium

Seven o,o'-dihydroxyazo dyes were synthesized and tested as metallochromic indicators for calcium: 1-(2-hydroxy-3-sulfo-5-chloro-1-phenylazo)-2-hydroxy-3-naphthoic acid (I), 1-(2-hydroxy-3-sulfo-5-chloro-1-phenylazo)-2-naphthol-3,6-disulfonic acid (II), 1-(2-hydroxy-6-sulfo-1-naphthylazo)-2-naphthol-3,6-disulfonic acid (III), 2,2'-dihydroxy-1, 1'-azonaphthalene-3,3', 6,6'-tetrasulfonic acid (IV), 1-(2-hydroxy-3-carboxy-1-naphthylazo)-2-naphthol-3,6-disulfonic acid (V), 1-(2,3-dihydroxy-1-naphthylazo)-2-naphthol-3, 6-disulfonic acid (VI), 1-(2,3-dihydroxy-6-sulfo-1-naphthylazo)-2-naphthol-3,6-disulfonic acid (VII). The acid dissociation constants and the formation constants of the calcium and magnesium chelates of these dyes were determined. The rate of the decomposition of these dyes and their calcium chelates in alkaline solutions was also examined. From the results of photometric and visual titrations of calcium in the presence of magnesium, indicators III and IV provide the sharpest end-points and the best stability in alkaline solutions.     

Potentiometrische Studien an Mischligand-Komplexen

1∶1∶1, mixed ligand complex formation of La(III) with ethylenediamine-N,N,N′,N′-tetra-acetic acid and certain hydroxy acids such as malic, tartaric, 1-hydroxy-2-naphthoic and 2-hydroxy-3-naphthoic acids has been shown potentiometrically.     

Solid-phase extraction followed by liquid chromatography-tandem mass spectrometry for the determination of hydroxylated benzophenone UV absorbers in environmental water samples

A procedure for the determination of six derivatives of 2-hydroxybenzophenone, used as UV absorbers, in water samples is presented. Compounds were first concentrated using a solid-phase extraction (SPE) cartridge and then selectively determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) using electrospray ionization (ESI). The effect of different parameters on the performance of concentration and determination steps is discussed. The highly polar and acidic 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (BP-4) required the use of ammonium acetate as modifier during desorption of SPE cartridges and also to improve the performance of its separation in the LC column. Under optimized conditions, the proposed method provided limits of quantification from less than 1 to 32 ng L⁻¹, depending on the compound and the type of water sample. Recoveries from the SPE step (83-105%) remained unaffected by the nature of the matrix; however, the efficiency of electrospray ionization was compound and sample dependant. Real sample analysis reflected the presence of three of the six investigated species (BP-4, 2-hydroxy-4-methoxybenzophenone, BP-3, and 2,4-dihydroxybenzophenone, BP-1) in the aquatic environment, particularly in raw wastewater samples. In this latter matrix, BP-4 was the compound presenting the highest concentrations; moreover, it was poorly removed in sewage treatment plants and consequently it also appeared in river water.     

Chloride present in biological samples as a tool for enhancement of sensitivity in capillary zone electrophoretic analysis of anionic trace analytes

Effects originating from the variability of the sample matrix can be efficiently eliminated when the separation conditions are selected so that compounds of like charge with high concentration referred to as macrocomponents are embodied into the system of transient isotachophoresis. For stacking and separation of anionic trace analytes in biological samples, the presence of chloride is shown to be important to balance out effects of other macrocomponents that act against isotachophoretic stacking. Having acetoacetate, malate, citrate, and some drug metabolites in untreated human serum samples, the stacking mechanism of these compounds in an electrolyte system comprising 5 mM mandelic acid and epsilon -aminocaproic acid, pH 3.8, is explained. Analytes are monitored by indirect UV-absorption detection. Attention is paid to the minimum chloride concentration required with respect to the concentration ratio of phosphate (stacker) and lactate (destacker) present in the sample so as to ensure both stacking and separation of trace analytes. Insight into the separation process is given both with computer simulations and experiments. For selected analytes, the effect of chloride concentration on quantitative evaluation, sensitivity and limit of detection is demonstrated as well. Moreover, the applicability of the mobility window between phosphate and lactate for an additional group of metabolites is sketched.     

A study of the interaction between humic acids and acidic metabolites of phenanthrene by capillary electrophoresis

Humic acids (HA) are able to interact with a wide range of pollulants and can influence their solubility, transport and bioavailability. In order to study the interaction between polar aromatic hydrocarbons and these macromolecules, an affinity capillary electrophoretic method, the Hummel-Dreyer (HD) method in its modified version, has been used. Two acidic metabolites of phenanthrene: 1-hydroxy-2-naphthoic acid (1-HNA) and 3,4-dihydroxybenzoic acid (3,4-DBA) were studied. The analysis for the binding studies was carried out by injecting a solution of HA in 25 mM ammonium hydrogen carbonate buffer (pH 9) into an uncoated fused-silica capillary, filled with buffer solutions of 1-HNA or 3,4-DBA in varying and increasing amounts. The results obtained indicate that both compounds bind to HA, as had been confirmed by dialysis experiments and literature data. CE proved to be a useful technique for investigating the link between xenobiotics and environmental macromolecules.     

Preconcentration and determination of calcium and magnesium in brine with flow-injection systems

On-line preconcentration on a chelating resin (Dowex A-1) and elution with 0.1 M hydorchloric acid is followed by spectrophotometry based on the metal complexes formed with 1- (2-hydroxy-4-diethylamino-1-phenylazo)-2-hydroxynaphthalene-3,6-disulfonic acid. The total concentration of calcium and magnesium is determined; in a second sample, calcium is masked with a ligand buffer containing excess of barium(II) and EGTA, and magnesium is determined. The calcium concentration is measured by difference. Magnesium (1–30 μg l^?1 and calcium (8– 10 μg l^?1) in 2.5 M sodium chloride can be determined. Calcium and magnesium in analytical reagent-grade sodium chloride and potassium chloride and primary standard sodium chloride are aslo determined. The method based on the exchange between calcium ions and Mg(EDTA) is proposed to enchance the sensitivity for calcium.     

Lewis acid-assisted oxidative cross-coupling of 2-naphthol derivatives with copper catalysts

The oxidative coupling reactions between 2-naphthol and 3-hydroxy-2-naphthoic acid derivatives using a copper catalyst under an O₂ atmosphere in the presence of a catalytic amount of the Lewis acid, such as Yb(OTf)₃, were carried out. A highly cross-coupling selective or specific reaction effectively proceeded to give a C₁ symmetrical BINOL derivative.     

Evidence for a trianion intermediate in the metalation of 4-hydroxy-6,7-dimethoxy-8-methyl-2-naphthoic acid. Methodology and application to racemic 5,5'-didesisopropyl-5,5'-dialkylapogossypol derivatives

The metalation of 4-hydroxy-6,7-dimethoxy-8-methyl-2-naphthoic acid (8) affording trianion 6 is presented and applied to the regioselective efficient construction of a series of 5,5'-didesisopropyl-5,5'-dialkylapogossypol derivatives 3 that are potent pan-active inhibitors of antiapoptotic Bcl-2 family proteins.     

Dynamic labeling of diagnostically significant microbial cells in cerebrospinal fluid by red chromophoric non-ionogenic surfactant for capillary electrophoresis separations

During bacterial infections of the central nervous system the number of microorganisms in the cerebrospinal fluid is often ranging from few up to hundreds of cells per milliliter. The electrophoretic techniques with the UV-detection reach a detection limit for whole cells of approximately 10⁷ cells per milliliter. The coupling of the filtration cartridge with capillary isoelectric focusing can improve the detection limit by four orders of magnitude. In order to improve the detection limit the red non-ionogenic surfactant 1-[[4-(phenylazo)phenyl]azo]-2-hydroxy-3-naphthoic acid polyethylene glycol ester, PAPAN 1000, has been prepared and used for the dynamic labeling of analytes before filtration of the sample with a concentration modulation in the analysis of proteins or microorganisms. Values of isoelectric points of labeled analytes have been calculated using pI markers detectable at 515 nm and have been found comparable with pI of the native compounds. Minimum detectable amounts of proteins and microorganisms were lower than nanograms and a hundred labeled cells, respectively. The introduced method, coupling of the filtration cerebrospinal fluid spiked with microorganisms and labeled by PAPAN, facilitates their rapid CIEF separation in the pH gradient pH range of 2–5 at their clinically important level 10¹ to 10² cells per milliliter.     

带有致钝取代基的萘衍生物和SO3的反应研究

研究了一系列带有醛基、苯甲酮基、羧基、酯基和硝基等致钝取代基的萘衍生物与SO₃的反应。1-萘甲醛的单磺化得到比例为55:9:6:30的5-、6-、7-和8-磺酸取代物。1-苯甲酮萘则以83:11:6的比例得到5-、6-和7-磺酸取代物。1-硝基萘专一地得到5位磺化产物,1-萘甲酸和1-萘甲酸甲酯得到5位和8位取代产物。所有的2位取代萘衍生物均先得到5和8位取代产物,在过量磺化中生成的主产物为5,7-二磺酸取代物,提出了生成SO₃络合物及迫位磺化的历程,报道了8-磺酸-1-萘甲酸酐的物理数据。     

Ultra-performance liquid chromatographic determination of manufacturing intermediates and subsidiary colors in D&C Red No. 34 and its lakes

An ultra-performance liquid chromatography (UPLC) method was developed to determine the manufacturing intermediates and subsidiary colors in the monosulfo monoazo color additive D&C Red No. 34 and its lakes. This method is currently used for batch certification of the color additives by the U.S. Food and Drug Administration to ensure that each lot meets published specifications for coloring drugs and cosmetics. The new UPLC method has replaced an HPLC method for determining the intermediates and a TLC method for determining the subsidiary colors. The intermediates are 2-amino-1-naphthalenesulfonic acid (Tobias acid) and 3-hydroxy-2-naphthalenecarboxylic acid (3-hydroxy-2-naphthoic acid). Subsidiary colors are positional isomers of the major dye component or related compounds containing lower numbers of substituent groups. The analytes are identified by comparison of their UPLC retention times and UV or visible absorption spectra with those of standards. Validation studies showed that peak area calibrations for the analytes were generally linear (R > 0.999), and recoveries were 98-103%. The LODs were 0.002-0.02%, and the RSDs at the specification levels were 0.7-2.2%. Survey analyses of 12 samples of certified D&C Red No. 34 straight colors and lakes from six domestic and foreign manufacturers yielded results for the intermediates by UPLC and HPLC that were consistent within experimental error. The UPLC analyses yielded results for the subsidiary colors that were consistently lower than results previously obtained by TLC, which we attribute to limitations of the TLC method. The new UPLC method provides sharper peaks, better peak separation, and faster analysis times than the formerly used HPLC method and is more accurate, much faster, and much less labor-intensive than the formerly used TLC method.     

P2O5-Hexamethyldisiloxane (HMDS): An Efficient System to Induce the Three-Component Reaction of Enolic Systems,Aromatic Aldehydes,and Acetonitrile

Three-component reaction of an enolizable compound, such as acetophenone, methyl acetoacetate, 4-hydroxycoumarin, 2-naphthol, or 3-hydroxy-2-naphthoic acid; an aromatic aldehyde, and acetonitrile induced by phosphorus pentoxide and hexamethyldisiloxane leads to 2-acetylamino ketones, methyl 3-(acetylamino aryl methyl)-3-oxobutanoates, 3-(acetylamino aryl methyl)-4-hydroxycoumarins, 1-(acetylamino aryl methyl)-2-naphthols, or 4-(acetylamino aryl methyl)-3-hydroxy-2-naphthoic acids in excellent yields.     

Quantification of anions and cations in environmental water samples. Measurements with capillary electrophoresis and indirect-UV detection.

The aim of this study was to validate two separation methods for determination of inorganic anions and cations from natural waters with capillary electrophoresis (CE) by using indirect-UV detection. The research is related to method development for screening of groundwater samples obtained in site investigations for spent fuel of the Finnish nuclear industry. In CE analysis, anions were separated in pyromellitic acid (pH 7.7) in the order bromide, chloride, sulphate, nitrite, nitrate, fluoride and dihydrogenphosphate. Cations were separated at pH 3.6 after anions using an 18-crown-6-ether solution. In these analyses, ammonium migrated first followed by potassium, calcium, sodium and magnesium. The concentrations of the ions in the natural water samples were calculated by using two or three calibration curves made using reference solutions at concentration levels of 0.5-250 mg/l. The repeatabilities of the anion and cation methods were tested using laboratory-made reference sample mixtures with high and low salt concentrations. The limits of quantification in the analyses were between 0.02 and 0.1 mg/l, depending on the ion. Concentrations of ions tested in natural waters varied from a few milligrams to tens of grams per litre.     

Method for the rapid synthesis of highly functionalized 2-hydroxy-1-naphthoates. Syntheses of the naphthoic acid components of neocarzinostatin chromophore and N1999A2

We describe a four-step sequence for the synthesis of complex 2-hydroxy-1-naphthoic acids involving Z-selective olefination of benzaldehyde derivatives with a novel dioxolenone-containing phenyl phosphonate reagent, followed by dioxolenone cleavage with alkaline trifluoroethanol and oxidative cyclization (Mn(OAc)(3)) of the resultant trifluoroethyl beta-keto esters. [reaction: see text]