Determination of pKa values of benzoxa-, benzothia- and benzoselena-zolinone derivatives by capillary electrophoresis. Comparison with potentiometric titration and spectrometric data.
Acidity constants of benzoxa-, benzothia- and benzoselena-zolinone derivatives were determined by capillary electrophoresis, potentiometry and spectrophotometry experiments. These three analytical techniques gave pK(a) results that were in good agreement. A convenient, accurate and precise method for the determination of pK(a) was developed to measure changes in acidity constants induced by heteroatom or 6-benzoyl substituted derivatives. pK(a) values were determined simultaneously for two compounds characterized by different electrophoretic mobility (micro(e)) and pK(a) value and in the presence of an analogous neutral marker.
Foulon
C
C
Laboratoire de Chimie Analytique, EA 4034, Faculté des Sciences Pharmaceutiques et Biologiques, Université de LILLE 2, Lille Cedex, France.
Duhal
N
N
Lacroix-Callens
B
B
Vaccher
C
C
Bonte
J P
JP
Goossens
J F
JF
D000143:Acids / Q000737:chemistry; D000465:Algorithms; D052160:Benzothiazoles / Q000737:chemistry*; D001583:Benzoxazoles / Q000737:chemistry*; D002021:Buffers; D019075:Electrophoresis, Capillary; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D016566:Organoselenium Compounds / Q000737:chemistry*; D023303:Oxazolidinones / Q000737:chemistry*; D011199:Potentiometry; D013056:Spectrophotometry, Ultraviolet
D000143:Acids; D052160:Benzothiazoles; D001583:Benzoxazoles; D002021:Buffers; D016566:Organoselenium Compounds; D023303:Oxazolidinones