In this report, we describe a simple visible light-triggered Barbier-type reaction by employing acetenyl ketones with benzyl trifluoroborates. Through a radical-radical cross-coupling process, this photocatalytic protocol furnished a wide range of tertiary propargyl alcohols. Mechanistic investigation indicated that proton-coupled electron transfer (PCET) might be involved in the photochemical transformations.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
August 2018
To determine the absorption properties and study the intestinal absorption kinetics of poncidin in rats. In situ single pass perfusion model was combined with High Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS/MS) method to investigate the intestinal absorption characteristics and calculate absorption parameters with aspects of drug absorption, concentration and perfusion medium. The absorption of poncidin under acid condition at pH 6.
View Article and Find Full Text PDFTo establish a sensitive and specific LC-MS/MS method for determination of the binding conditions of ponicidin with bovine serum albumin (BSA) and analysis of its mechanism. The protein binding rates and related binding constants of ponicidin in BSA samples were determined by ultrafiltration and LC-MS/MS. Scatchard equation was used to calculate the binding constant (Ka) of ponicidin in BSA samples as well as the number of binding sites (n), and the mechanism on ponicidin binding with BSA was explored.
View Article and Find Full Text PDFA sensitive and simple liquid chromatography -: electrospray ionization mass spectrometry method has been established and validated for the quantification of Guanfu base G in rats. Phenoprolamine hydrochloride was selected as the internal standard. Sample preparation involved simple liquid-liquid extraction by ethylacetate with high efficiency.
View Article and Find Full Text PDFA reversed-phase ion pair chromatography method with liquid-liquid extraction analytical method was developed and validated for the determination of antazoline hydrochloride in plasma and excreta of rat. The aim of our study was to characterize the preclinical pharmacokinetics and excretion profiles of antazoline hydrochloride in rats after intravenous injection at the dose of 10 mg/kg. Plasma and excreta samples were extracted with ethyl acetate, and phenacetin was used as the internal standard.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
June 2013
In order to evaluate the pharmacokinetics characteristic of antazoline hydrochloride in Beagle dogs, a sensitive and specific HPLC method was developed and validated using phenacetin as the internal standard (IS). The analyte and the IS were extracted from dog plasma by ethyl acetate under the basic condition. The analyte was separated by a C18 column and detected with a variable wavelength UV-detector.
View Article and Find Full Text PDFA highly specific and sensitive liquid chromatography-tandem mass spectrometry method has been developed and validated for the determination of ponicidin in dog plasma. The plasma samples were prepared using liquid-liquid extraction with ethyl acetate as the extraction solvent. Chromatographic separation was accomplished on a Waters XTerra MS C18 column.
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