ISSN:
0899-0042
Keywords:
enantioselective hydrolysis
;
lipase
;
2-chloroethyl esters
;
2-arylpropanoic acids
;
chiral liquid chromatography
;
enantiomer separation
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A technique based exclusively on chiral reversed-phase liquid chromatography has been shown to greatly facilitate studies of enantioselectivity in lipase-catalyzed hydrolysis of chiral organic esters. Only two sets of experimental data are needed to calculate the enantioselectivity (E) of a kinetically controlled enantiomer-differentiating reaction of this kind, viz. the enantiomeric excess of the product (eep) or substrate (ees), and the degree of substrate conversion (c). The product enantiomers are well separated on a BSA-based column, giving eep directly. In addition, separation of the (unresolved) ester substrate from the enantiomeric products gives c by integration. Via an optimization of the mobile phase used in the chiral chromatographic system, both these parameters can often be determined in a single run. Highly precise and detailed kinetic studies of the enzymatic reaction can thus be performed. In this way, E-values have been determined for a series of 2-chloroethyl 2-arylpropanoates hydrolyzed in the presence of a Candida cylindracea lipase at pH 6.0 and 7.1. Effects on the E-values from a partial purification and further processing of the lipase have also been studied.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/chir.530040206
