Relative acidity scale of bile acids through ESI-MS measurements.
The anion proton affinity of the most important human bile acids and those of the corresponding keto bile acids have been examined in order to establish a true (intrinsic) relative acidity scale. The measurements have been carried out in the gas-phase using the Cooks' kinetic method. The remarkably high acidity of cholic acid with respect to the other bile acids was confirmed. Rationalization of the differences found for the various acids and comparisons with the available solution-phase data are discussed with the help of theoretical calculations.
Bortolini
Olga
O
Dipartimento di Chimica, Università della Calabria, Via Bucci 12 C, 87036 Rende (CS), Italy. o.bortolini@unical.it
Fantin
Giancarlo
G
Ferretti
Valeria
V
Fogagnolo
Marco
M
Giovannini
Pier Paolo
PP
Medici
Alessandro
A
D001647:Bile Acids and Salts / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D008968:Molecular Conformation; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
D001647:Bile Acids and Salts