Steering the antitumor drug discovery campaign towards structurally diverse indolines

•Indoline framework is perpended as a privileged heterocycle in medicinal chemistry.•Indoline ring exists in structurally and mechanistically diverse antitumour chemical architectures.•Indoline ring containing mutitargeting agents as well PROTACs have also been reported recently.•Efforts have been made to derisk the aniline alerts associated with indolines.•A good number of anticancer indolines have also been patented in the last decade.