Pictet-Spengler Reactions of Nb-Hydroxytryptamines and Their Application to the Synthesis of Eudistomins

Methods for preparing Nb-hydroxytryptamines, their PictetSpengler reactions with various aldehydes via nitrones, and their asymmetric inductions are reviewed.Syntheses of oxathiazepine-containtng eudistomins and related natural products which incorporate these reactions are also reviewed.Contents : I. Introduction 11. Preparation of Nb-hydroxyhyptamines 111.PictetSpengler reactions of Nb-hydroxytryptamines with simple aldehydes IV.Asymmetric PictetSpengler reactions of Nb-hydroxytryptamines V. Application of the PictetSpengler reaction of Nb-hydroxytryptamines to the synthesis of natural products V-1.Synthesis of neoechinulin analog V-2.Synthesis of verruculogen TR-2 and fumitremorgin C-1.3-Dipolar cycloaddition of nitrones derived from Nb-hydroxytryptamines V-3.Synthesis of oxathiazepine-containing eudistomins V-3.1.Pictet-Spengler reactions of Nb-hydroxytryptamines with cysteinals V-3-2.Oxathiazepine ring formation from substituted b-carbolines V-3-3.Intramolecular Plctet-Spengler reaction to form an oxathiazepine-P-carboline ring V1.Conclusion