Predmetom publikácie je komplexné spektrálne a fyzikálno- chemické hodnotenie mono[{3-[4-(2-etoxyetoxy)- benzoyloxy]-2-hydroxypropyl}-terc-butylamónium] fumarátu, potenciálneho ultrakrátko pôsobiaceho blokátora ß1-adrenergných receptorov. Totožnosť hodnotenej zlúčeniny (pracovne označenej ako UPB-2) bola potvrdená 1H-, 13C-NMR a IR spektrami. V rámci stanovenia základných fyzikálno-chemických charakteristík bola určená hodnota teploty topenia, rozpustnosť v spektre rozpúšťadiel, čistota (adsorpčná chromatografia na tenkej vrstve), povrchová aktivita (nepriama Traubeho stalagmometrická metóda), acidobázické charakteristiky (hodnota pKa stanovená alkalimetrickou titráciou), hodnoty log ε (spektrofotometricky v UV/ /VIS oblasti), ako aj hodnotenie vplyvu kyslého a zásaditého prostredia na stabilitu UPB-2. Ďalšími experimentálne stanovenými parametrami boli lipohydrofilné deskriptory určené pomocou RP-HPLC (log k’), shake flask metódou stanovené hodnoty rozdeľovacích koeficientov Pexp (resp. log Pexp) v rôznych rozdeľovacích systémoch. Na základe log Pexp-údajov bola predpovedaná schopnosť UPB-2 prechádzať cez hematoencefalickú bariéru. Pre stanovenie obsahu UPB-2 bola aplikovaná RP-HPLC (reversed-phase HPLC) metóda vnútorného štandardu a UV/VIS spektrofotometria pri vlnovej dĺžke 260 nm (vodné prostredie) a 258 nm (prostredie metanolu).
The present paper aims at a complex spectral and physicochemical evaluation of mono[{3-[4-(2-ethoxyethoxy)- benzoyloxy]-2-hydroxypropyl}-tert-butylammonium] fumarate, the potential ultra-short acting blocker of ß1-adrenergic receptors. The identity of the evaluated compound (labelled as UPB-2) was confirmed by 1H-, 13C-NMR and IR spectral data as well. The estimated physicochemical parameters included melting point data, solubility in various media, purity checking (adsorption thin-layer chromatography), surface activity determination (non- -direct Traube stalagmometric method), acidobasic characteristics (pKa value determination by alkalimetric titration), log ε values estimation (spectrophotometrically in UV/VIS region) and a study of the influence of acidic and alkaline media towards the stability of UPB-2. Other experimentally estimated values were lipohydrophilic descriptors using RP- -HPLC (log k’) and the log Pexps in various lipohydrophilic media by the shake flask method. Based on the log Pexp readouts, the ability to permeate across the brain-blood barrier was predicted. For the content determination of UBP-2 the RP-HPLC (reversed-phase HPLC), the method of an internal standard and UV/VIS spectrophotometry at the wavelength of 260 nm (aqueous medium) and at 258 nm (methanolic medium) was applied.
Predmetom prezentovanej práce je komplexné spektrálne a fyzikálno-chemické hodnotenie mono[{3-[4-(2-etoxyetoxy)-benzoyloxy]-2-hydroxypropyl}-izopropylamónium]fumarátu, potenciálneho ultrakrátko pôsobiaceho ß1-blokátora. Totožnosť študovanej substancie (pracovne označenej ako UPB-1) bola potvrdená 1H- a 13C-NMR spektrami ako aj IR spektrometriou. Medzi stanovené základné fyzikálno-chemické charakteristiky patrilo určenie teploty topenia, rozpustnosti v spektre rozpúšťadiel, overenie čistoty (adsorpčná chromatografia na tenkej vrstve), určenie povrchovej aktivity (Traubeho stalagmometrická metóda), acidobázické charakteristiky (hodnota pKa pomocou alkalimetrickej titrácie), určenie hodnôt log ? s využitím spektrofotometrie v UV/VIS oblasti, ako aj hodnotenie vplyvu kyslého a zásaditého prostredia na stabilitu študovanej látky. Ďalšími experimentálne stanovenými parametrami boli lipohydrofilné charakteristiky pomocou RP-HPLC (log k’), shake flask metódou stanovené hodnoty rozdeľovacích koeficientov Pexp (resp. log Pexp) v rôznych lipohydrofilných prostrediach. Na základe log Pexp- dát sa predikovala schopnosť látky prechádzať cez hematoencefalickú bariéru. Pre stanovenie obsahu UPB-1 sa použila RP-HPLC (reversed-phase HPLC) metóda vnútorného štandardu a UV/VIS spektrofotometria pri vlnovej dĺžke 260 nm (vodné prostredie) a 258 nm (prostredie metanolu).
The present paper deals with a complex spectral and physicochemical evaluation of mono[{3-[4-?-(2-etoxyetoxy)-benzoyloxy]-2-hydroxypropyl}-isopropylammonium]fumarate, a potential ultrashort acting ß1-blocker. The identity of the substance under study (labelled as UPB-1) was confirmed by 1H- and 13C-NMR spectra as well as IR spectrometry. The determined fundamental physicochemical characteristics included the determination of the melting point, solubility in a spectrum of solvents, verification of purity (adsorption thin-layer chromatography), determination of surface activity (Traube’s stalagmometric method), acidobasic characteristics (pKa value by means of alkalimetric titration), determination of log ? values using spectrophotometry in UV/VIS region, as well as the evaluation of the effect of acid and basic media on the stability of the substance under the study. Other experimentally determined parameters were lipohydrophilic characteristics essayed by means of RP-HPLC (log k’), and the shake-flask method was employed to determine the values of the partition coefficients Pexp (resp. log Pexp) in different lipohydrophilic media. On the basis of log Pexp- data, the ability of the substance to penetrate the hematoencephalic barrier was predicted. To determine the UPB-1 content, RP-HPLC (reversed-phase HPLC) method of the internal standard and UV/VIS spectrophotometry at the wavelength of 260 nm (aqueous medium) and 258 nm (methanol medium) were used.
Predmetom práce bolo doplnenie niektorých experimentálne stanovených fyzikálno-chemických deskriptorov 1-[3-(3-propoxyfenylkarbamoyloxy)-2-hydroxypropyl]-4-(3-trifluórmetylfenyl)piperazíniumchloridu (pracovne označeného ako 8e), účinnej, relatívne vysokolipofilnej zlúčeniny proti netuberkulóznemu M. kansasii My 235/80. Identita látky 8e bola potvrdená 1H- a 13C-NMR spektrami, spektrometriou v IR oblasti ako aj elementárnou analýzou. Výstup z hmotnostnej spektrometrie potvrdil existenciu molekulového iónu [M + H+]+. Čistota hodnotenej zlúčeniny 8e bola overená pomocou adsorpčnej chromatografie na tenkej vrstve, stabilita jej vodných a metanolových roztokov bola hodnotená pri pôsobení UV/VIS žiarenia. Hodnoty niektorých základných fyzikálno-chemických charakteristík molekuly 8e stanovených v redchádzajúcich publikáciách (pKa, log Pexp) boli korelované s konštantami, ktoré prislúchajú niektorým v praxi používaným antimykobakteriálne aktívnym molekulám (izoniazid, pyrazínamid, kyselina para -aminosalicylová, etiónamid, streptomycín). Pre stanovenie obsahu molekuly 8e sa použila RP-HPLC (reversed-phase HPLC) metóda vnútorného štandardu a UV/VIS spektrofotometria pri vlnovej dĺžke 238 nm (vodné prostredie) a 244 nm (prostredie metanolu).
The purpose of the paper was the completing of the experimentally estimated physicochemical descriptors spectrum of 1-[3-(3-propoxyphenylcarbamoyloxy)-2-hydroxypropyl]-4-(3-trifluoromethylphenyl)piperazinium chloride (labelled as 8e), an effective, highly lipophilic compound against non-tuberculous M. kansasii My 235/80. The identity of the structure 8e was verified by 1H- and 13C-NMR spectral data, IR spectrometry and by elemental analysis as well. The readout from mass spectrometry confirmed an existence of the molecular ion [M + H+]+. The purity of the evaluated compound 8e was checked by absorption thin-layer chromatography, the stability of its aqueous and methanolic solutions was investigated under UV/VIS light. The values of some physicochemical descriptors assigned to 8e, which had been previously published (pKa, log Pexp), were correlated with the constants associated with some antimycobacterially active molecules which are commonly used in therapeutical practice (isoniazid, pyrazinanide, para-aminosalicylic acid, ethionamide, streptomycine). For the content determination of the molecule of 8e, RP-HPLC (reversed-phase HPLC) method with an internal standard and UV/VIS spectrophotometry at the wavelength of 238 nm (aqueous medium) and at 244 nm (methanolic medium) were used.
- MeSH
- Mycobacterium Infections, Nontuberculous drug therapy immunology MeSH
- Spectroscopy, Near-Infrared MeSH
- Chemistry, Pharmaceutical methods MeSH
- Chemistry, Physical methods MeSH
- Chromatography, Liquid MeSH
- Phenylcarbamates analysis MeSH
- Mass Spectrometry MeSH
- Magnetic Resonance Spectroscopy MeSH
- Piperazines analysis MeSH
- Spectrophotometry MeSH
V rámci komplexného štúdia vzťahov medzi chemickou štruktúrou, fyzikálno-chemickými vlastnosťami a biologickou (antiarytmickou, antihypertenzívnou) aktivitou duálne pôsobiacich zlúčenín boli pripravené 1-[3-(Y-alkoxyfenylkarbamoyloxy)-2-hydroxypropyl]-4-(2-?-metylfenyl)piperazíniumchloridy s pracovným označením 7a–7d. Chemická štruktúra príslušných bázických foriem (7a2C–7d2C) a monochloridov (7a–7d) bola potvrdená 1H-NMR, 13C-NMR, MS a IR spektrálnou ako aj elementárnou analýzou. Medzi stanovené základné fyzikálno-chemické charakteristiky patrilo určenie teploty topenia, rozpustnosti v spektre rozpúšťadiel, overenie čistoty (adsorpčná chromatografia na tenkej vrstve), určenie povrchovej aktivity (Traubeho stalagmometrická metóda), acidobázických charakteristík (hodnoty pKa pomocou alkalimetrickej titrácie) a určenie hodnôt log ? s využitím spektrofotometrie v UV/VIS oblasti. Medzi ďalšie experimentálne stanovené parametre patrili lipohydrofilné charakteristiky pomocou chromatografie na tenkej vrstve s obráteným systémom fáz (RM), RP-HPLC (log k’), shake flask metódou stanovené hodnoty rozdeľovacích koeficientov Pexp (resp. log Pexp) v systéme oktán-1-ol/tlmivý fosforečnanový roztok.
1-[3-(Y-Alkoxyphenylcarbamoyloxy)-2-hydroxypropyl]-4-(2-methylphenyl)piperazinium chlorides (labelled as 7a–7d) were prepared within a complex study of the relationships between the chemical structure, physicochemical properties and biological (antiarrhythmic, antihypertensive) activity of dual acting compounds. Chemical structures of basic forms (labelled as 7a2C–7d2C) and appropriate monochlorides (labelled as 7a–7d) were confirmed by 1H-NMR, 13C-NMR, MS and IR spectral and elemental analysis. The estimated physicochemical parameters included the melting point data, solubility profile in various media, purity checking (adsorption thin-layer chromatography), surface activity determination (Traube stalagmometric method), acidobasic characteristics (pKa value determination by alkalimetric titration) as well as the log ? values estimation by UV/VIS spectrophotometry. Other experimental values under consideration were lipohydrophilic characteristics using reversed-phase thin-layer chromatography (RM readouts) RP-HPLC (log k’ data) and the log Pexps estimated in octan-1-ol/phosphate buffer medium.
In this work, we describe the introduction of a post-column solid-state reactor in the HPLC system used for the analyses of amino acids. The reactor used was filled with copper(II) oxide. Passage of the analytes through the reactor leads to the formation of Cu(II) complexes. Unlike free amino acids, the Cu-complexes show significant absorbance in the UV region and accordingly sensitivity of UV-VIS detection is increased by two to three orders of magnitude. As a result of this improvement in sensitivity, we have obtained LOD values in micromolar range and good linearity over the studied concentration range (5.0×10(-5) to 2.0×10(-3) mol/L). The method exhibits advantages typical of solid-state reactors, such as negligible loss of efficiency due to the derivatization, simplicity of realization and a long-term durability. The presented system brings an easy and versatile solution for UV-VIS detection of coordinating compounds, which do not normally absorb well in the UV-VIS region.
OBJECTIVES: The aim of the study was to examine oxidation of carcinogenic Sudan I by peroxidase and characterize the structure of its two major peroxidasemediated metabolites. Another target of the study was to evaluate a mechanism of this oxidation. METHODS: Thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) with ultraviolet (UV) and visible (VIS) detection was employed for the separation of Sudan I metabolites formed by peroxidase. UV/ VIS-, and mass- spectroscopy as well as nuclear magnetic resonance (NMR) were used to characterize structures of two major Sudan I metabolites. RESULTS: Peroxidase oxidizes Sudan I by a one electron oxidation to eight products. Two major Sudan I metabolites were isolated by TLC on silica gel and HPLC and structurally characterized. The major product formed during the Sudan I oxidation by peroxidase is Sudan I metabolite M2, which corresponds to a Sudan I dimer molecule. The second major metabolite (M1) is the product of secondary, enzyme independent reactions, being formed from the Sudan I dimer that lost the benzenediazonium moiety. CONCLUSIONS: The data are the first report on structural characterization of Sudan I metabolites formed by its oxidation with peroxidase.
- MeSH
- Chromatography, Thin Layer MeSH
- Electrons MeSH
- Spectrometry, Mass, Electrospray Ionization MeSH
- Mass Spectrometry MeSH
- Carcinogens chemistry MeSH
- Horseradish Peroxidase MeSH
- Magnetic Resonance Spectroscopy MeSH
- Naphthols chemistry MeSH
- Oxidation-Reduction MeSH
- Hydrogen Peroxide chemistry MeSH
- Spectrophotometry, Ultraviolet MeSH
- Chromatography, High Pressure Liquid MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
In this research, a microbial endophytic strain obtained from the rhizosphere of the conifer Taxus baccata and designated as Streptomyces sp. AC35 (FJ001754.1 Streptomyces, GenBank) was investigated. High 16S rDNA gene sequence similarity suggests that this strain is closely related to S. odorifer. The major fatty acid profile of intracellular lipids was also carried out to further identify this strain. Atomic force microscopy and scanning acoustic microscopy were used to image our strain. Its major excreted substances were extracted, evaluated for antimicrobial activity, purified, and identified by ultraviolet-visible spectroscopy (UV-vis), liquid chromatography-mass spectrometry (LC-MS/MS) and nuclear magnetic resonance as the bioactive isoflavone aglycones-daidzein, glycitein and genistein. Batch cultivation, performed under different pH conditions, revealed enhanced production of antimycin components when the pH was stable at 7.0. Antimycins were detected by HPLC and identified by UV-vis and LC-MS/MS combined with the multiple reaction monitoring. Our results demonstrate that Streptomyces sp. AC35 might be used as a potential source of effective, pharmaceutically active compounds.
BACKGROUND: Uric acid is the final product of purine metabolism in humans. It was determined that this compound has important antioxidative properties and it may be oxidized to allantoin by various reactive oxygen species. Therefore, the measurement of allantoin may be useful for the determination of oxidative stress in humans. METHODS: We measured allantoin and uric acid in human plasma and erythrocytes obtained from patients with chronic renal failure before hemodialysis (n=30) and blood donors (n=30). We used a method based on selective isolation of allantoin from deproteinized plasma and erythrocyte lysate samples on AG 1-X8 resin and its derivatization to glyoxylate-2, 4-dinitrophenylhydrazone. Separation of glyoxylate-2, 4-dinitrophenylhydrazone from interfering substances was achieved on reversed phase HPLC with gradient elution and UV/VIS detection at 360 nm. Uric acid was determined by reversed phase HPLC with UV/VIS detection at 292 nm. RESULTS: We found significant differences in allantoin and uric acid concentration between the patients with chronic renal failure and the control group both in plasma (20.5+/-6.5 micromol/L and 323.9+/-62.9 micromol/L vs. 2.1+/-1.1 micromol/L and 270.1+/-62.3 micromol/L, p<0.05) and erythrocytes [82.8+/-39.1 nmol/g hemoglobin (Hb) and 110.7+/-28.8 nmol/g Hb vs. 20.1+/-6.1 nmol/g Hb and 82.1+/-23.7 nmol/g Hb, p<0.05]. CONCLUSIONS: Significant higher levels of allantoin in both plasma and erythrocytes of patients with chronic renal failure indicate that allantoin may be used as a good marker of oxidative stress.
- MeSH
- Allantoin blood MeSH
- Antioxidants metabolism MeSH
- Biomarkers blood MeSH
- Adult MeSH
- Erythrocytes metabolism MeSH
- Financing, Organized MeSH
- Uric Acid blood MeSH
- Middle Aged MeSH
- Humans MeSH
- Oxidative Stress MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Chromatography, High Pressure Liquid MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
In this study, selective green synthesis of gold nanoparticles (nAu) with the use of Tarragon extract (Artemisia dracunculus) was investigated. Characterization of the synthetized nAu was carried out using several techniques including: UV-Vis, SEM, zeta potential analysis, DLS, and ATR-FTIR. Based on measurements of Tarragon extract by HPLC-MS, significant chemical substances participating as reducing and stabilizing agents were identified. FTIR confirmed typical functional groups that could be found in these acids on the nAu surface, such as O-H, C=O and C-O. The effects of various parameters (concentration of Tarragon extract, Au precursor, and initial pH of the synthesis) on the shape and size of the nanoparticles have been investigated. UV-Vis and SEM confirmed the formation of nAu at various concentrations of the extract and Au precursor and showed correlation between the added extract concentration and shift in maximal absorbance towards higher frequencies, indicating the formation of smaller nanoplates. Zeta potential determined at various pH levels revealed that its value decreased with pH, but for all experiments in the pH range of 2.8 to 5.0, the value is below - 30 mV, an absolute value high enough for long-term nAu stability. In order to evaluate nAu catalytic activity, the reduction of 4-nitrophenol to 4-aminophenol by sodium borohydride was used as a model system. The reaction takes place 1.5 times faster on Au-triangles than on Au-spherical NPs.
- MeSH
- Aminophenols chemistry MeSH
- Borohydrides chemistry MeSH
- Catalysis MeSH
- Hydrogen-Ion Concentration MeSH
- Metal Nanoparticles chemistry MeSH
- Microscopy, Electron, Scanning MeSH
- Nitrophenols chemistry MeSH
- Artemisia chemistry MeSH
- Plant Extracts analysis chemistry MeSH
- Spectrophotometry, Ultraviolet MeSH
- Spectroscopy, Fourier Transform Infrared MeSH
- Tandem Mass Spectrometry MeSH
- Green Chemistry Technology methods MeSH
- Particle Size MeSH
- Chromatography, High Pressure Liquid MeSH
- Gold chemistry MeSH
- Publication type
- Journal Article MeSH
