Design of new drugs for the treatment of Alzheimer's disease based on tacrine structure.

Tacrine was the first drug approved by FDA for the treatment of Alzheimer's disease. However, its use was restricted in function of side effects observed in some patients. Investigations on the structural basis by which tacrine inhibits cholinesterases activity brought new perspectives for the design of more potent analogs with fewer side effects. This review discusses the recent advances on the development of tacrine-structure-based compounds capable to target multiple molecules involved in Alzheimer's disease. Detailed information on strategies of molecular modifications commonly used in medicinal chemistry, such as bioisosterism, hybridization, dimerization and simplification is presented as well.