Chiral discrimination of cyclic 1,3-amino alcohol enantiomers

Racemic 1,3-amino alcohols were resolved via lipase-catalysed O-acylation o f their Z derivatives, using vinyl butyrate in different ethers as solvents . In accordance with the empirical rule, most of the screened lipases prefe rred the 1S enantiomer. In order to monitor the enzymatic reactions a high-performance liquid chrom atographic method was developed. The applied chiral stationary phase (Chira lcel OD) allowed simultaneous separation of all the four isomers which were present in the reaction mixture. Retention mechanisms of alcohol and ester analogues were investigated in detail. Besides the direct way, indirect se paration involving precolumn derivatization with 1-fluoro-2,4-dinitrophenyl -5-L-alaninamide permitted the differentiation of 1,3-amino alcohol enantio mers with high resolution. In combination with the addition of standards, b oth direct and indirect methods can be used to identify absolute configurat ions and hence to determine the enzyme selectivity.