title: Studies of enantiomerization of chiral 3,4-dihydro-1,2,4-benzothiadiazine 1,1-dioxide type compounds.
abstract: An on-column HPLC procedure using a chiral stationary phase (CSP) was developed for the determination of rate constants and free energy barriers of enantiomerization of (+/-)IDRA21. Subsequently, the HPLC method was applied for investigation of two structurally related chiral compounds. The individual enantiomers of the studied compounds were isolated in parallel by preparative HPLC and rate constants and free energy barriers of enantiomerization were determined in different solvents. The on-column enantiomerization data revealed that CSP induces different rate constants for the two enantiomers. The results generated off-line were used to determine the influence of solvents on the racemization of (+) and (-) IDRA21 and to gain further insight into the enantiomerization mechanism of chiral 3,4-dihydro-1,2,4-benzothiadiazine 1,1-dioxide type compounds.
authors.affiliation: Dipartimento di Scienze Farmaceutiche, Università degli Studi di Modena e Reggio Emilia, Modena, Italy. pippi@unimo.it
authors.forename: G
authors.initials: G
authors.lastname: Cannazza
authors.forename: D
authors.initials: D
authors.lastname: Braghiroli
authors.forename: A
authors.initials: A
authors.lastname: Tait
authors.forename: M
authors.initials: M
authors.lastname: Baraldi
authors.forename: C
authors.initials: C
authors.lastname: Parenti
authors.forename: W
authors.initials: W
authors.lastname: Lindner
mesh_terms: D001581:Benzothiadiazines / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: C425327:3,4-dihydro-1,2,4-benzothiadiazine-1,1-dioxide; D001581:Benzothiadiazines