Table 1.

Inhibitory activities of target compounds 1–16 against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in comparison with the standards galantamine and rivastigmine.

compound	R1	R2	R3	AChEa (%)	AChE IC50 (µM)	BuChEa (%)	BuChE IC50 (µM)
1	Me	piperidine		74.1 ± 0.9	12.7	10.0 ± 0.8	>100
2	Et	piperidine		77.8 ± 0.4	8.58	15.7 ± 1.9	>100
3	Pr	piperidine		79.4 ± 0.3	6.57	21.0 ± 2.5	>100
4	Et	morpholine		16.1 ± 4.2	>100	17.8 ± 3.4	>100
5	Pr	morpholine		25.9 ± 3.2	>100	14.4 ± 2.4	>100
6	Et	Et	Et	42.2 ± 4.3	>100	34.2 ± 2.6	>100
7	Me	Bu	Me	38.0 ± 4.2	>100	20.4 ± 5.8	>100
8	Et	Bu	Me	23.5 ± 2.2	>100	4.7 ± 3.0	>100
9	Pr	Bu	Me	44.5 ± 1.1	>100	29.0 ± 2.9	>100
10	Me	Bu	Et	23.6 ± 2.3	>100	43.6 ± 3.0	>100
11	Et	Bu	Et	24.6 ± 1.9	>100	51.0 ± 2.9	>100
12	Pr	Bu	Et	38.4 ± 1.3	>100	51.1 ± 3.3	>100
13	Bu	Bu	Et	33.5 ± 3.4	>100	48.7 ± 2.6	>100
14	Me	Pr	Me	42.2 ± 1.3	>100	22.3 ± 4.6	>100
15	Et	Pr	Me	45.3 ± 3.4	>100	36.8 ± 2.1	>100
16	Et	Pe	Me	50.6 ± 1.8	>100	46.3 ± 2.0	>100
Galantamine				87.9 ± 0.5	1.1	62.1 ± 1.4	73.6
Rivastigmine				54.8 ± 4.4	87.9	72.9 ± 1.5	11.6

^a Percentage of inhibition at 100 μM expressed as the mean ± SD (n = 5)