Density functional theory calculations on the effects of fluorine substitution on the chemical properties of Donepezilanti-Alzheimer drug

Donepezilis used to treat dementia in people with Alzheimer's disease. This drug is alsoapplied to treat dementia in people with Parkinson's disease [1]. Donepezil is in a class ofmedications called cholinesterase inhibitors that improves mental function by increasing theamount of acetylcholine (a neurotransmitter) in the brain [2].Selective fluorination in drugdesign is an effective method to improve drug efficiency that is used for this anti-Alzheimerdrug in this work(Fig. 1) [3]. The fluorination effect on the special properties of Huperzine A,which affect the efficiency of this drug, was studied by density functional theory (DFT)methods. For this purpose 7 fluorinated derivatives of this drug were designed as new drugsand were investigated theoretically.