In this study, three new triterpenes (
1−
3) and fourteen known triterpenoids (
4−
17) were isolated from the ethanol extract of Kochiae Fructus, and their structures were elucidated by analyzing UV, IR, HR-ESI-MS, 1D, and 2D NMR
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In this study, three new triterpenes (
1−
3) and fourteen known triterpenoids (
4−
17) were isolated from the ethanol extract of Kochiae Fructus, and their structures were elucidated by analyzing UV, IR, HR-ESI-MS, 1D, and 2D NMR spectroscopic data. Among them, compounds
6,
8, and
11−
17 were isolated for the first time from this plant. The screening results of the glucose uptake experiment indicated that compound
13 had a potent effect on glucose uptake in 3T3-L1 adipocytes at 20 μM. Meanwhile, compounds
3,
9 and
13 exhibited significant inhibitory activities against
α-glucosidase, with IC
50 values of 23.50 ± 3.37, 4.29 ± 0.52, and 16.99 ± 2.70 µM, respectively, and their
α-glucosidase inhibitory activities were reported for the first time. According to the enzyme kinetics using Lineweaver–Burk and Dixon plots, we found that compounds
3,
9 and
13 were
α-glucosidase mixed-type inhibitors with
Ki values of 56.86 ± 1.23, 48.88 ± 0.07 and 13.63 ± 0.42 μM, respectively. In silico molecular docking analysis showed that compounds
3 and
13 possessed superior binding capacities with
α-glucosidase (3A4A AutoDock score: −4.99 and −4.63 kcal/mol). Whereas compound
9 showed +2.74 kcal/mol, which indicated compound
9 exerted the effect of inhibiting
α-glucosidase activity by preferentially binding to the enzyme−substrate complex. As a result, compounds
3,
9 and
13 could have therapeutic potentials for type 2 diabetes mellitus, due to their potent hypoglycemic activities.
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