title: Gas chromatographic method for the quantification of the new calcium antagonist benidipine hydrochloride in plasma using electron capture detection.
abstract: A gas chromatographic assay procedure was developed for measuring subnanogram order concentrations of (+/-)-(R*)-2,6-dimethyl-4-(m-nitrophenyl)-1,4-dihydropyridine-3,5- dicarboxylic acid (R*)-1-benzyl-3-piperidinyl ester, methyl ester hydrochloride (benidipine hydrochloride, KW-3049) in plasma. KW-3049 yielded the oxidation product partially during gas chromatography. To avoid decomposition, KW-3049 was oxidized in advance by nitrogen dioxide, extracted by diethylether under alkaline condition, chromatographed on the OV-1 column and measured using electron capture detector.
authors.affiliation: Pharmaceutical Research Laboratories, Kyowa Hakko Kogyo Co., Ltd., Shizuoka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kobayashi
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
authors.forename: A
authors.initials: A
authors.lastname: Inoue
authors.forename: T
authors.initials: T
authors.lastname: Oka
authors.forename: N
authors.initials: N
authors.lastname: Nakamizo
mesh_terms: D000818:Animals; D002121:Calcium Channel Blockers / Q000097:blood*; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D009543:Nifedipine / Q000031:analogs & derivatives* / Q000097:blood; D010084:Oxidation-Reduction; D051381:Rats
chemical_list: D002121:Calcium Channel Blockers; C050883:benidipine hydrochloride; D009543:Nifedipine