title: Chromatographic separation of the diastereomers of a dihydropyridine-type calcium channel antagonist as the bis-3,5-dinitrobenzoates.
abstract: The diastereomeric components of the calcium channel antagonist RS-93522-004 are separated as the bis-3,5-dinitrobenzoate ester by reversed-phase high-performance liquid chromatography. The diastereomer ratio determination is shown to be precise, accurate and sensitive, and is not affected by the reaction yield of the derivatization with 3,5-dinitrobenzoyl chloride. The four individual stereoisomers of RS-93522-004 were independently shown to have equal reactivity toward 3,5-dinitrobenzoyl chloride.
authors.affiliation: Analytical and Environmental Research, Syntex Research, Palo Alto, CA 94304.
authors.forename: J R
authors.initials: JR
authors.lastname: Kern
authors.forename: D M
authors.initials: DM
authors.lastname: Lokensgard
authors.forename: T Y
authors.initials: TY
authors.lastname: Yang
mesh_terms: D002121:Calcium Channel Blockers / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D004095:Dihydropyridines / Q000302:isolation & purification*; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D009579:Nitrobenzoates / Q000302:isolation & purification; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: D002121:Calcium Channel Blockers; D004095:Dihydropyridines; D007202:Indicators and Reagents; D009579:Nitrobenzoates; C059331:RS 93522-004; C059332:RS 93522-004 bis(3,5-dinitrobenzoic acid ester)