The document reports results from assays testing compounds 15a, 15b, tacrine, 6-chlorotacrine, and donepezil against human BChE, human AChE, and bovine AChE. It provides IC50 values in nM for each compound and enzyme combination. It also reports reduction of fluorescence percentages from a thioflavin T competition assay for tacrine, 6-chlorotacrine, donepezil, 15a, and 15b. Structures are provided for compounds 15a and 15b, which are donepezil-tacrine hybrids.