Hericinosides A–M, Cyathane Diterpene Glycosides with α-Glucosidase Inhibitory Activity from the Medicinal Fungus Hericium erinaceus

Thirteen new cyathane diterpene glycosides, hericinosides A-M (1-13), and six known analogs, were isolated from the rice media fermentation of the medicinal fungus Hericium erinaceus. The sugar parts of 1 and 2 were highly modified, forming a unique 5/6/7/5/5/5 ring new skeleton system. All structures were elucidated based on spectroscopic data, and their relative configurations were determined according to the ROESY analysis. Possible biosynthetic pathways for compounds 1-13 were discussed. Compounds 6 and 19 showed significant α-glucosidase inhibitory activity with IC₅₀ values of 82.7 and 199.5 μM, respectively. The results will facilitate further studies to expand the use of diterpene glycosides from this mushroom for actual and potential biological properties in metabolic regulation.