title: Enantioresolution of five β-blockers by reversed-phase high-performance liquid chromatography using fifteen chiral derivatizing reagents having amino acids or their amides as chiral auxiliaries on a cyanuric chloride platform.
abstract: Enantioseparation of five β-blockers, namely, (R,S)-atenolol, (R,S)-propranolol, (R,S)-bisoprolol, (R,S)-metoprolol and (R,S)-carvedilol, was achieved as their diastereomers prepared with chiral derivatizing reagents (CDRs) synthesized on a cyanuric chloride platform. Fifteen CDRs were synthesized by nucleophilic substitution of the Cl atom in cyanuric chloride or its 6-methoxy derivative with amino acids (namely, L-Leu, L-Val, D-Phg, L-Met and L-Ala) or their amides as chiral auxiliaries. The diastereomers were synthesized under microwave irradiation for 70 or 100 s at 85% power. Separation of diastereomers was carried out on a C(18) column and gradient eluting mixtures of methanol with aqueous trifluoroacetic acid with UV detection at 230 nm. Separation efficiencies of the reagents were compared on the basis of effect of chiral auxiliaries (i.e. amino acids or amino acid amides) and achiral substituents (i.e. chlorine or methoxy group) in the CDRs. The method was validated for detection limit, linearity, accuracy and precision.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, India. rbushfcy@iitr.ernet.in
authors.forename: Ravi
authors.initials: R
authors.lastname: Bhushan
authors.forename: Shuchi
authors.initials: S
authors.lastname: Dixit
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000737:chemistry* / Q000302:isolation & purification; D000577:Amides / Q000737:chemistry*; D000596:Amino Acids / Q000737:chemistry*; D056148:Chromatography, Reverse-Phase / Q000379:methods*; D008872:Microwaves; D011412:Propanolamines / Q000737:chemistry / Q000302:isolation & purification; D012044:Regression Analysis; D015203:Reproducibility of Results; D013237:Stereoisomerism; D014227:Triazines / Q000737:chemistry*
chemical_list: D000319:Adrenergic beta-Antagonists; D000577:Amides; D000596:Amino Acids; D011412:Propanolamines; D014227:Triazines; C019309:cyanuric chloride