Novel Selenoureas Based on Cinchona Alkaloid Skeleton: Synthesis and Catalytic Investigations.

Mariola Zielińska-Błajet,Joanna Najdek

doi:10.3390/ma14030600

Abstract

An efficient approach to the synthesis of chiral selenoureas consisting of Cinchona alkaloid scaffolds was described. The new selenoureas were assessed as bifunctional organocatalysts in the asymmetric Michael addition reactions under mild conditions. The best results were obtained for selenoureas bearing the 4-fluorophenyl group. These catalysts promoted the reactions with enantioselectivities of up to 96% ee. Additionally, the catalytic performance of the thiourea and selenourea counterpart was compared.

Highlights

In recent years, growing attention has been focused on the synthesis and applications of selenourea derivatives
Michael alkaloid-derived selenoureas, and we demonstrate their organocatalytic potential in alkaloid-derived selenoureas, and we demonstrate their organocatalytic potential in asymmetric Michael additions
Preparation of Compounds selenoureas were prepared by coupling reactions of 9-epiCinchona alkaloid-based

Summary

Introduction

In recent years, growing attention has been focused on the synthesis and applications of selenourea derivatives. The structures of selenoureas are closely related to those of analogs of oxygen and sulfur compounds [1,2,3], but the presence of larger, more polarizable selenium results in a change of significant properties They possess various biological properties, such as antioxidant [4,5], antibacterial and antifungal [6], antileishmanial [7], pesticidal [8], and anti-urease activity [9]. Selenoureas demonstrate enzyme inhibition, free-radical scavenging, and anticancer activity [10,11] These compounds are very useful starting materials for the synthesis of selenium-containing heterocycles [12,13] and are used for anion binding and recognition [14,15]. Bolm and coworkers were the first to apply a selenourea derivative as a chiral catalyst in the asymmetric

Methods

Results

Conclusion