TL;DR: This chapter discusses an area of indole alkaloids, which has been neglected in the series for over 30 years—namely, the ajmaline group of alkaloid, where numerous advances in chemistry and biosynthesis have been made recently.
Abstract: Publisher Summary This chapter discusses an area of indole alkaloids, which has been neglected in the series for over 30 years—namely, the ajmaline group of alkaloids, where numerous advances in chemistry and biosynthesis have been made recently. The number of known ajmaline structures has grown markedly in recent years to a present count of 77. Some of these might be artefacts and a few structures have not been convincingly determined. In addition, seven bisindole alkaloids containing at least one monomeric ajmalan unit have been isolated, increasing the total number to 84. Ajmaline alkaloids contain the polycyclic ajmalan ring system. The “biogenetic numbering” of Le Men and Taylor is used throughout the chapter. The priority sequence for the C-17 substituents in the Cahn–Ingold–Prelog system is different in the absence and presence of the COOCH, substituent at C-16. All of the ajmaline alkaloids found thus far occur in the plant family Apocynaceae. They have been recognized in the following genera Alstonia , Aspidospenna , Cabucala , Melodinus , Rauvolfia , Tonduzia (Alstonia), and Vinca .
TL;DR: The number of known ajmaline structures has grown markedly in recent years to a present count of 77 as mentioned in this paper, which has not been convincingly determined and some of these might be artefacts.
Abstract: Publisher Summary This chapter discusses an area of indole alkaloids, which has been neglected in the series for over 30 years—namely, the ajmaline group of alkaloids, where numerous advances in chemistry and biosynthesis have been made recently. The number of known ajmaline structures has grown markedly in recent years to a present count of 77. Some of these might be artefacts and a few structures have not been convincingly determined. In addition, seven bisindole alkaloids containing at least one monomeric ajmalan unit have been isolated, increasing the total number to 84. Ajmaline alkaloids contain the polycyclic ajmalan ring system. The “biogenetic numbering” of Le Men and Taylor is used throughout the chapter. The priority sequence for the C-17 substituents in the Cahn–Ingold–Prelog system is different in the absence and presence of the COOCH, substituent at C-16. All of the ajmaline alkaloids found thus far occur in the plant family Apocynaceae. They have been recognized in the following genera Alstonia , Aspidospenna , Cabucala , Melodinus , Rauvolfia , Tonduzia (Alstonia), and Vinca .