Design, synthesis and evaluation of isaindigotone derivatives as acetylcholinesterase and butyrylcholinesterase inhibitors

A series of isaindigotone derivatives 5a–d and 6a–d were designed, synthesized and evaluated as acetylcholinesterase and butyrylcholinesterase inhibitors. Results showed that the novel class of isaindigotone derivatives could inhibit both cholinesterases and the selectivity of AChE over BuChE inhibition was related to the aromatic, the species and length of the alkyl amino side chain of compounds. The structure–activity relationships were discussed and their multiple binding modes were further clarified in the molecular docking studies.