Kaurane-type diterpenoids from Chromoleana odorata, their X-ray diffraction studies and potent α-glucosidase inhibition of 16-kauren-19-oic acid

A new diterpenoid, 15-angeloyloxy-16,17-epoxy-19-kauronic acid (1), along with five known metabolites, 16-kauren-19-oic acid (2), 6′-hydroxy-2′,3′,4,4′-tetramethoxychalcone (3), isosakuranetin (4), acacetin (5), and kaempferide (6) was isolated from the organic extracts of the roots of Chromoleana odorata. Their structures were determined by spectroscopic evidences. The structures of 1 and 2 were further confirmed by single-crystal X-ray diffraction studies. Compound 2 exhibited significant α-glucosidase inhibitory and antibacterial activities against Escherichia coli and Bacillus subtilis.

Graphical abstractA new diterpenoid, 15-angeloyloxy-16,17-epoxy-19-kauronic acid, along with five known metabolite, 16-kauren-19-oic acid, was isolated from the organic extracts of the roots of Chromoleana odorata and confirmed by single-crystal X-ray diffraction studies. 16-Kauren-19-oic acid exhibited significant α-glucosidase inhibitory activity.Figure optionsDownload full-size imageDownload as PowerPoint slide