Chiral recognition of verapamil by cyclodextrins studied with capillary electrophoresis, NMR spectroscopy, and electrospray ionization mass spectrometry.
Capillary electrophoresis (CE) allows the observation of the opposite affinities of the enantiomers of (+/-)-verapamil [2-isopropyl-2,8-bis(3,4-dimethoxyphenyl)-6-methyl-6-azaoctannitrile+ ++, VP] toward beta-cyclodextrin (beta-CD) and heptakis(2,3, 6-tri-O-methyl)-beta-CD (TM-beta-CD). In addition, in the presence of beta-CD in the background electrolyte, longer migration times and lower separation factors were observed compared to TM-beta-CD. The binding constants of (+)- and (-)-VP with beta-CD and TM-beta-CD determined using (13)C NMR spectroscopy explain the results observed in CE. Electrospray ionization mass spectrometry (ESI-MS) was used as an alternative technique for the characterization of VP-CD complexes.
Chankvetadze
B
B
Institute of Pharmaceutical Chemistry, University of Münster, Hittorfstrasse 58-62, 48149 Münster, Germany.
Burjanadze
N
N
Pintore
G
G
Strickmann
D
D
Bergenthal
D
D
Blaschke
G
G
D002121:Calcium Channel Blockers / Q000737:chemistry*; D003505:Cyclodextrins / Q000494:pharmacology*; D019075:Electrophoresis, Capillary; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D013237:Stereoisomerism; D014700:Verapamil / Q000032:analysis / Q000737:chemistry*; D047392:beta-Cyclodextrins
D002121:Calcium Channel Blockers; D003505:Cyclodextrins; D047392:beta-Cyclodextrins; D014700:Verapamil; C031215:betadex