ABSTRACT
References .......................................................................................................................... 640
Optically pure compounds are useful as building blocks and intermediates of pharmaceuticals
and fragrances. Chiral compounds can be synthesized mainly by the following three methods:
1. A chiral pool method to obtain them by chemical conversion of naturally occurring
chiral compounds such as L-amino acids, D-sugars, and organic acids [1]
2. An optical resolution of racemic mixture to obtain them by preferential crystallization
[2], diastereomeric resolution [3], kinetic resolution [4], and chromatographic separ-
ation with chiral stationary phases [5]
3. An asymmetric synthesis method with chiral auxiliaries [6], metal-catalysts [7], and
biocatalysts [8]
The optimal method to obtain chiral compounds is selected according to the quantity
needed, allowable lead time, and cost. The biocatalytic process has several advantages: (1) it is
generally highly regio-and stereoselective; (2) it is performed at a moderate temperature in
aqueous solution; (3) biocatalysts can be reproduced easily and inexpensively; and (4) it is low
environmental burden.
