Chapter 3 Naturally occurring halogenated pyrroles and Indoles

Abstract

This chapter describes naturally occurring halogenated pyrroles and indoles. More than 3800 naturally occurring organohalogen compounds are now known to exist, and new examples of these natural products continue to be discovered. This area has been extensively reviewed both in total and by individual organohalogen (organochlorine, organobromine, and organofluorine). Given the enormous reactivity of the n -excessive heterocycles pyrrole and indole towards electrophilic halogenation, it is not surprising that the biohalogenation of these heterocycles has led to a large number of natural halogenated pyrroles and indoles. The chapter focuses mainly on recent discoveries in this area that have not been previously reviewed as well as summarizes some of the classic examples of these fascinating natural products, some of which have extraordinary biological activity. In addition to halogenated pyrroles and indoles, the chapter includes carbazoles and carbolines.