title: The effect of organic solvents on the determination of cyclic boronates of some beta-blockers by gas chromatography/mass spectrometry.
abstract: Formation cyclic boronates for beta-blockers, by use of triethylamine (TEA) and pyridine as catalysts, gives more effective product yield. Eleven beta-blockers, formed by cyclic boronation with n-butylboronic acid and TEA, produced higher yields than by on-column thermal reaction and seven beta-blockers were shown to give the highest yields in the phenyl cyclic boronation with pyridine or TEA by on-column thermal and general reaction. The phenyl cyclic boronate of nadolol produced one peak in the chromatogram and the n-butyl cyclic boronate showed two peaks. On-column derivatization and n-butylboronic acid and pyridine was effective in saving analysis time and for convenience, even though some n-butyl cyclic boronates by cyclic boronation with TEA gave a better yield. In n-butyl cyclic boronation with pyridine by on-column thermal reaction the detection limits were 0.1 to 4 ng/microL in urine with a signal-to-noise ratio of 10:1.
authors.affiliation: Doping Control Centre, Korea Institute of Science and Technology, Seoul, Korea.
authors.forename: J
authors.initials: J
authors.lastname: Lee
authors.forename: D S
authors.initials: DS
authors.lastname: Lho
authors.forename: M
authors.initials: M
authors.lastname: Kim
authors.forename: K
authors.initials: K
authors.lastname: Kim
authors.forename: Y
authors.initials: Y
authors.lastname: Kim
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000737:chemistry* / Q000652:urine; D001896:Boron Compounds / Q000737:chemistry*; D003500:Cyclization; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D012997:Solvents / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D000319:Adrenergic beta-Antagonists; D001896:Boron Compounds; D012997:Solvents