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Identifier

000413027

Title

α) Στερεοεκλεκτικές βιοαναγωγές α-αμιδο-β-κετο εστέρων β) Στερεοεκλεκτική σύνθεση οπτικά ενεργών γ-βουτυρολακτονών μέσω ενζυμικών αναγωγών 2-μονο- και 2,2-δι-υποκατεστημένων 1,3-δικετονών

Alternative Title

a) Stereoselective bioreduction of α-amido-β-keto esters b) Stereoselective synthesis of optically pure β,γ-disubstituted and trisubstituted γ-butyrolactones via enzymatic reduction of 2-substituted and 2,2-disubstituted 1,3-diketones

Author

Γιαννόπουλος, Βασίλειος Π.

Thesis advisor

Σμόνου, Ιουλία

Reviewer

Στρατάκης, Εμμανουήλ
Βασιλικογιαννάκης, Γεώργιος

Abstract

The subject of the present thesis is the study of stereoselective enzymatic reductions with ketoreductases for the preparation of compounds, which are useful chiral intermediates-building blocks for the synthesis of high added value natural products. In the first part, the stereoselective bioreduction of α-amido-β-keto esters using various isolated ketoreductases for the synthesis of optically pure β-hydroxy-α-amido esters is presented. In particular, the stereoselective synthesis of the β-hydroxy-α-amido esters, which are derivatives of allo-threonine and β-hydroxy leucine, using NADPH-dependent ketoreductases was achieved with excellent reaction rates and excellent diastereoselectivity. In the case of the β-hydroxy-α-amido ester, which is derivative of allo-threonine, the appropriate ketoreductase, which led to the synthesis of anti-tert-butyl 2-acetamido-3-hydroxybutanoate in high enantioselectivity, was also determined. In the second part, the stereoselective synthesis of optically pure β,γ-disubstituted and trisubstituted γ-butyrolactones via enzymatic reduction of 2-substituted and 2,2-disubstituted 1,3-diketones using ketoreductases is described and has resulted in the synthesis of three different γ-butyrolactones in high chemical yields, high diastereoselectivity and in some cases with good enantioselectivity. One remarkable result is that, one of the three γ-butyrolactones was synthesized successfully in a one-pot process without isolation of the intermediate products and using only one enzyme.

Language

Greek

Subject

Chiral intermediates

Ketoreductases

Stereoselective bioreduction

Κετορεδουκτάσες

Στερεοεκλεκτική βιοαναγωγή

Χειρόμορφα ενδίαμεσα

β-hydroxy-α-amido esters

β-υδρόξυ-α-αμιδο εστέρες

γ-butyrolactones