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Updated: May 9, 2026

Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade
Published on: August 14, 2019
Isodonoids A-L: Ent-kauranoid diterpenoid-flavanone conjugates from Isodon rubescens
Can-Can Wang1, Meng-Yu Bao1, Hui-Ying Li1
1State Key Laboratory of Mechanism and Quality of Chinese Medicine & Faculty of Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, 999078, China.
None:
Twelve undescribed ent-kauranoid diterpenoid-flavanone conjugates, isodonoids A‒L (1‒12), were isolated from the aerial part of Isodon rubescens. This is the first time that diterpenoid-flavanone conjugates were discovered from the plant kingdom. Compounds 1‒4 possess an undescribed diterpenoid-flavanone skeleton formed by a direct C-C bond between C-17 of the diterpenoid unit and C-3 of the flavanone A-ring. Compounds 5‒12 are unreported diterpenoid-flavanone conjugates with an oxygen bridge between C-16 and C-3' or C-4' of their precursors. Their structures and absolute configurations were established by HRESIMS, NMR spectroscopic data, DP4+ analyses, and ECD calculations. Compounds 5, 11, 12, and 14 exhibited remarkable cytotoxicity against the cancer cell lines MDA-MB-231, HepG2, H1299, and A375, with IC50 values ranging from 5.0 ± 0.4 to 14.9 ± 0.8 μM. Moreover, 11 and 12 were found to promote apoptosis in MDA-MB-231 cells in a dose-dependent manner.
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