Indolo[2,3-a]carbazoles: diversity, biological properties, application in antitumor therapy

This review presents the history of the discovery of indolo[2,3-a]carbazoles, lists the currently known natural compounds of this subclass, and gives the sources for their isolation. The main approaches used to obtain synthetic indolo[2,3-a]carbazoles are described, and examples of compounds from this group that are most promising because of their high antitumor activity are given. The spectrum of biological properties of natural and synthetic compounds of this subclass is highlighted. The molecular mechanisms of their antitumor action as the most significant in the context of clinical use are separately considered. Particular attention is paid to indolo[2,3-a]- carbazoles that have reached clinical trials or are already in use for the treatment of malignant neoplasms.