Isatin dimers and their biological activities.

Dimerization is a promising strategy to develop novel drug candidates that could extend the biological spectrum, enhance the activity, overcome drug resistance, as well as improve pharmacological, pharmacokinetic, and physicochemical profiles. Isatin dimers possess a broad spectrum of biological properties and the isatin dimer indirubin has already been used in the clinic, revealing the potential of isatin dimers as putative drugs. This review covers the recent advances of isatin dimers as pharmacologically significant scaffolds and the structure-activity relationship to set up the direction for the design and development of isatin dimers with higher efficiency and lower toxicity.