Review article

Some Examples of Non-catalytic, Catalytic and Biocatalytic Preparations of Chiral Molecules

Vitomir Šunjić ; Ruđer Bošković Institute. P.O.B. 1016, 41001 Zagreb, Croatia

Abstract

Practical solutions for the preparation of enantiomerically pure compounds (EPC) by enantioselective synthesis have now been found for most important organic reactions, and for a number of economically important classes of organic compounds. This author-review, therefore, covers only representative examples of those methods to which the author's group made some contribution.
Non-catalytic preparation of chiral molecules can be achieved either by separation of racemic mixtures, or by enantioselective synthesis using stoichiometric quantities of a chiral auxiliary agent. Examples of various separations of racemic 1,4-benzodiazepines will be given. Non-catalytic enantioselective preparation of specific a-amino acids and some therapeutically important compounds, will examplify the use of chiral auxiliaries, derived from the »chiral pooh of Nature.
Biocatalytic transformations of chiral molecules that are not natural substrates of the enzymes, represent a rapidly growing field of application of enzymes and microorgasnisms in organic synthesis. Recently, we successfully used microbial lipases for enantioselective hydrolysis of some precursors of C3 and C4 chiral synthons, for kinetic resolution of rac 3-(2-nitrophe- noxy) butanoates, precursors for l,5-benzoxazepin-4(5H)-ones with ACH inhibitory activity, and also in chemoenzymatic syntehsis of S-fenpropimorph, the biologically active enantiomer of a commercially important fungicide. Complete stereoselectivity in the hydrolysis and acylation of resorcyclic acid macrocyclic lactones, intermediates in the production of a-zearanol, a commercially important growth-promoting agent, catalyzed by microbial lipases, prompted us to propose a new »helical model« for interaction of substrates with the Pseudomonas sp. lipase active site.

Keywords

Hrčak ID:

136880

URI

https://hrcak.srce.hr/136880

Publication date:

1.11.1994.

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