Imidazoquinolines: Recent Developments in Anticancer Activity.

Cancer remains one of the unsolved diseases of today's advanced drug discovery world even though it is known to humans for centuries. There is continued effort to discover new chemotherapeutic agents to improve the outcome of cancer patients. Small-molecule agonists at tolllike receptor 7 and 8 (TLR7/8) have recently generated renewed interest in cancer research owing to their profound antitumoral activity. TLR-7/8 agonist imidazoquinolines (Imiquimod, and Resiquimod) and dual inhibitor of phosphoinositide 3-kinase and mammalian target of rapamycin (NVP-BEZ235) have emerged as clinically important candidates for treating cancers. This article reviews briefly the synthesis, structure-activity relationship (SAR) and biological activities of clinically studied imidazoquinolines along with novel emerging preclinical imidazoquinolines for the anticancer activity.