Development of a Chiral Stationary Phase Base don Cinchodine. Comparison with a quinine-based Chiral Column?

SONIA KEUNCHKARIAN; JAIVER OSORIO GRISALES; JUAN M. PADRÓ; SUSANA BOERIS; CECILIA B. CASTELLS

CHIRALITY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2012 vol. 24 p. 512 - 518

0899-0042

A chiral anion-exchanger stationary phase based on cinchonidine (CD) was developed. Two columns were packed with and without endcapping (EC) treatment (CD-chiral stationary phase[CD-CSP(EC)] and [CD-CSP], respectively) and studied for their ability to separate N-2,4-dinitrophenyl α-amino acids (DNP-amino acids) enantiomers over a temperature range of 10?40 °C with a hydro-organic buffer mobile phase. The more hydrophobic, endcapped stationary phase showed significantly larger retentive capacity than the non-endcapped one. The apparent thermodynamic transfer parameters of the enantiomers from the mobile to both CSPs were estimated from van´t Hoff plots within the cited temperature range. Similar studies with two natural quinine-based columns (QN-CSP and QN-CSP(EC)) were previously reported. In this work, a critical comparison in the chiral recognition ability to DNP-amino acids of these cinchonidine and QN-based chiral columns was drawn. It has been found that QN-based CSPs show greater chiral recognition capability towards these derivatives than CD-CSPs. The influence of the QN methoxy group on the equilibrium constants of the enantioselective interaction between these DNP-amino acids with these two cinchona CSPs could be assessed. Chirality 24:512?518, 2012. © 2012 Wiley Periodicals, Inc.