LAUSR

Abstract A phytochemical study on whole Leathesia nana plants led to isolation of 22 compounds, including 12 bromophenols ( 1 – 12 ), 1 megastigmane sesquiterpene ( 13 ), 4 monoindole alkaloids ( 14 – 17 ), and 5 other small molecules ( 18 – 22 ). Their structures were elucidated by 1 H and 13 C NMR spectroscopy, HRESIMS data, and by comparison with closely related compounds published previously. Compounds 8 – 11 , 13 , 14 , and 17 – 22 were first reported from Leathesia nana , while 1 – 7 , 12 , 15 , and 16 had been previously isolated, which could be considered chemotaxonomic markers. In addition, the biological activities of all of the compounds were evaluated with protein tyrosine phosphatase 1b (PTP1B). Compounds 1 – 3 and 5 – 7 exhibited potent inhibitory effects on PTP1B with IC 50 values of 9.40, 4.30, 7.94, 14.64, 16.40, and 10.95  μ M, respectively, while the other compounds showed no obvious activities (IC 50 values > 20  μ M).