Table 3.

α-Glucosidase inhibitory activities of compounds 1−16 ^a .

Compound	α-glucosidase inhibitory activityb
	750 μM (%)	IC50 ± SD (μM)
1	37.4 ± 1.4	N.T.
2	42.0 ± 2.7	N.T.
4	49.9 ± 1.8	N.T.
5	93.4 ± 3.1	112.3 ± 4.5
7	86.9 ± 0.4	407.0 ± 3.3
8	77.3 ± 1.0	524.5 ± 2.7
9	48.9 ± 1.1	N.T.
10	92.1 ± 3.4	218.8 ± 5.6
acarbosec	50.7 ± 1.2	743. 4 ± 3.3

^aCompounds 3, 6, and 11−16 were inactive toward α-glucosidase at 750 μM (inhibition rate <30%). ^bValues represent means ± SD based on three individual experiments. ^cPositive control. N.T.: not tested.