Exploring plant-derived bisindole alkaloids: a comprehensive review of sources, phytochemistry and cytotoxicity

Bisindole alkaloids represent a notable class of natural compounds distinguished by their characteristic bisindole structure and recognized for their anticancer potential. Over the past nine decades, a plethora of bisindole alkaloids have been isolated from plants. The chemical compositions and cytotoxicity of these plant-derived bisindole alkaloids (PDBAs) have been elucidated. Currently, 735 PDBAs have been documented. Predominantly sourced from plants within the Apocynaceae family, these compounds demonstrate formidable cytotoxicity against various tumor types, such as colorectal cancer, breast cancer and lung cancer. This review comprehensively examines the sources, phytochemistry, and cytotoxicity of these compounds. Furthermore, it provides a summary of the structure–activity relationship (SAR) and the mechanisms through which PDBAs exert their cytotoxicity. In summary, the aim of this paper is to offer a comprehensive overview of the advancements in the investigation of PDBAs for their continued development and utilization.