Heterocyclic Chiral Auxiliaries in Total Synthesis of Natural Products

Abstract

Heterocyclic chiral auxiliary is widely considered to be an efficient choice to bring about asymmetric induction in the stereoselective synthesis of natural products. Various heterocyclic chiral auxiliaries are frequently used in asymmetric alkylation, Diels-Alder, Michael addition, and aldol reaction to synthesize complex chiral intermediates in enantiomerically pure form that are further employed in the synthesis of natural targets of biological and pharmaceutical importance. Amongst the various auxiliaries, Evans’ oxazolidinones and their sulfur analogues are the most sought after chiral auxiliaries in asymmetric synthesis owing to their ability to induce good to excellent selectivities. The versatility of oxazolidinones is brought forth by their utilization in the total synthesis of complex natural targets like brefeldin A, calcaripeptides A, B, and C, and apoptolidinone. In addition to Evans’ oxazolidinones, this chapter will also focus on application of Enders’ SAMP/RAMP hydrazone, camphorsultam, phosphonamide, pyrimidinone, and oxazolinyl ketone as chiral auxiliaries in the total synthesis of natural products and bioactive molecules.