ACHE and Alzheimer disease: The multipotent approach includes novel tacrine-melatonin hybrids, dual inhibitors of AChE and MAO or serotonin transporters, potent cholinesterase inhibitors with antioxidant and neuroprotective properties, gallamine-tacrine hybrids binding at cholinesterases and M2 muscarinic receptors, NO-donor, tacrine hybrids as hepatoprotective drugs focusing on AD or fluorescent tacrine, coumarin hybrids [23].