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Development and validation of LC—ESI—MS/MS method for simultaneous determination of four coumarin derivatives and an alkaloid from root and stem bark of Aegle marmelos Correa

Gajbhiye N. A., Makasana J., Dhanani T., Saravanan R.

Acta Chromatographica

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2016

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Vol. 28, no. 4

473--488

EN

Aegle marmelos Correa (Bael tree) is a medicinal fruit tree, widely used for healing purposes in various systems of medicines. Coumarins and alkaloids present in various parts of bael tree including roots and fruit pulp are the primary active constituents implicated for its biological activities. An efficient liquid chromatography–electrospray ionization—tandem mass spectrometry (LC—ESI—MS/MS) method was developed for identification and simultaneous determination of four coumarin derivatives, namely, umbelliferone, psoralene, marmin, and imperatorin, and an alkaloid, skimmianine, in root and stem bark of A. marmelos. The chromatographic separation of analytes was performed on Altima C18 (50 × 4.6 mm, 3 μm) column using methanol and 0.1% acetic acid in water (54:46, v/v) as the mobile phase under isocratic conditions. The LC–MS/MS parameters were optimized in the positive ionization mode using electrospray ionization source. The quantification of the analytes was performed using multiple reaction monitoring (MRM) transitions, umbelliferone (m/z 163.1 → 107.1), psoralene (m/z 187.2 → 131.1), marmin (m/z 333.5 → 163.2), imperatorin (m/z 271.1 → 203.1), and skimmianine (m/z 260.1 → 227.0). The extraction method was standardized for optimum yield of coumarin derivatives and the alkaloid in different extraction solvents. Higher yield of the analytes was found in methanolic extracts in comparisons to petroleum ether, chloroform, ethyl acetate, ethanol, and water. The method was validated for linear range, intra- and inter-batch precision and accuracy. The distribution of coumarin derivatives and an alkaloid was found to vary significantly in different plant samples, and their concentration was much higher in roots as compared to stem bark.

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Simultaneous and sensitive determination of eight coumarins in rat bile and urine after oral administration of Radix Angelicae Dahuricae extract by liquid chromatography-electrospray ionization-mass spectrometry

Huo H. L., Yu S. H., Liu X. Z., Meng Y., Ren Y. P., Zhang L. T.

Acta Chromatographica

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2013

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Vol. 25, no. 2

201--219

EN

A selective and sensitive liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method was developed and validated for analysis of xanthotoxol (1), xanthotoxin (2), isoimpinellin (3), bergapten (4), oxypeucedanin (5), imperatorin (6), cnidilin (7), and isoimperatorin (8) in rat bile and urine using pimpinellin as an internal standard (IS). An Agilent 1200 liquid chromatography system (Agilent Technologies, USA) equipped with a quaternary pump, an autosampler, and a column compartment was used for all analyses. Chromatographic separations were performed on a Sapphire C18 column (150 mm × 4.6 mm, 5 μm), and the column temperature was maintained at 30°C; the sample injection volume was 10 μL. The specificity, linearity, accuracy, precision, recovery, matrix effect, and several stabilities were validated for all analytes in the rat bile and urine samples. The method was successfully applied in monitoring the concentrations of eight coumarins in rat bile and urine after a single oral administration of Radix Angelicae Dahuricae extract with a dosage of 8.0 mL/kg. In the bile samples, the eight coumarins excreted completely in twenty-four hours. The average percentages of coumarins (1–8) excreted were 0.045%, 0.019%, 0.177%, 0.105%, 0.337%, 0.023%, 0.024%, 0.021%. In the urine samples, the eight coumarins excreted completely in seventy-two hours. The average percentages of coumarins (1–8) excreted were 1.78%, 0.095%, 0.130%, 0.292%, 0.082%, 0.008%, 0.005%, 0.004%. The method is robust and specific and it can successfully complete the requirements of the excretion study of the eight coumarins in Radix Angelicae Dahuricae.

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Computer-assisted searching for coumarins in Peucedanum alsaticum L. and Peucedanum cervaria (L.) Lap.

Skalicka-Woźniak K., Markowski W., Świeboda R., Głowniak K.

Acta Chromatographica

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2009

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Vol. 21, no. 4

531--546

EN

The objective of the work was continuation of our study on identification of target coumarins in extracts from Peucedanum alsaticum L. and Peucedanum cervaria (L.) Lap., by use of ChromSword, on the basis of relationships between retention data and descriptors such as partial molecular volume of structural fragments in water and energies of electrostatic interactions of bond dipoles with water (QSRR). The coumarins were mainly identified by comparing UV spectra from gradient runs with spectra from the literature. The presence of columbianadin, ostruthin, and 8-methoxypeucedanin in the fruits of P. cervaria (L.) Lap. and oxypeucedanin and isoimperatorin in the fruits of P. alsaticum was confirmed. The optimum conditions obtained from DryLab simulation were used for both RP-HPLC and RP-UPLC.

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Intermediates in the von Pechmann Reaction

Nowakowska E. M., Zaleski J., Kyzio J. B.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 7

1399-1399

EN

Condensation of meta-cresol with ethyl acetoacetate in dehydrated phosphoric acid is slow enough to observe formation and disappearance of the in termediates viz 1,2- di -hydro-4,7-dimethyl-4-(4-hydroxy-2-methylphenyl)-coumarin (3) and 1,2- di hydro- 4,7-dimethyl-4-(2-hydroxy-4-methylphenyl)-coumarin (4). GCMS analyses of the reaction mixtures indicated that 4,7-dimethylcoumarin (5) was formed from 3 and 4 by elimination of meta-cresol molecule. The compounds 3 and 4 were isolated by the column chromatography. Their structures were elucidated by the spectroscopic methods but unequivocal assignment of the structure to the particular isomer was not possible. The structures were resolved by X-ray diffraction studies.