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Updated: Mar 22, 2026

Author Spotlight: Integrating 2D-HPLC-MS and Molecular Networking in Natural Medicine Analysis
Published on: December 8, 2023
Leojaponic acids A and B, two new homologous terpenoids, isolated from Leonurus japonicus
Han-Kui Wu1, Yan-Jun Mao2, Shan-Shan Sun1
1College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China.
Abstract:
The present study aimed at isolation and purification of the bioactive terpenoids from the herb of Leonurus japonicus by chromatographic separations such as silica gel, sephadex LH-20 and C18 reversed phase silica gel, as well as preparative HPLC. As a result, leojaponic acids A (1, C17H24O4) and B (2, C18H26O4), two homologous terpenoids, together with (-)-loliolide (3), 1-(3-ethylphenyl) ethane-1, 2-diol (4) and dibutyl phthalate (5), were isolated from the EtOH extract of L. japonicus. All the chemical structures of the isolates were elucidated on the basis of 1D and 2D NMR analyses. Compounds 1 and 2 were new terpenoids, and Compounds 3 and 4 were isolated and identified for the first time from this plant. In addition, the α-glucosidase and tyrosinase inhibitory activity of the new compounds were evaluated.
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