The Carbolines

This chapter deals with the chemistry of the carboline ring systems. The chapter focuses on the general aspects of carboline chemistry, including the relevant findings, which emerged incidentally in the course of degradative and synthetic work in the field of indole alkaloid chemistry. Synthetic methods leading to the different oxidation states of the carboline ring systems, as well as the methods for the interconversion of these different oxidation states are summarized. The reactions at carbon and at nitrogen of fully aromatic carbolines, and their reduced and oxidized derivatives are reviewed. Nuclear rearrangements and methods for extending the tricyclic system to four and five rings are surveyed, and a discussion of the structure and chemistry of pseudo- and anhydro-bases derived from carbolines is presented. The chapter concludes by reviewing the biogenesis and biosynthesis of naturally occurring simple carbolines and the spectral data related to carbolines conclude this report.