A new highly oxygenated pregnane and two new 5-hydroxymethylfurfural derivatives from the water decoction of Poria cocos.

A new highly oxygenated pregnane steroid, pregn-7-ene-2β,3α,15α,20-tetrol (1) and two new 5-hydroxymethylfurfural derivatives, (5-formylfuran-2-yl)methyl 2-hydroxypropanoate (2) and (5-formylfuran-2-yl)methyl 2-(4-hydroxyphenyl)acetate (3), together with four known compounds, were isolated from the water decoction of Poria cocos. Their structures were established on the basis of extensive spectroscopic analysis. Compound 1 showed moderate inhibitory activity and a known compound (3S,6S)-3-[(1R)-1-hydroxyethyl]-6-(phenylmethyl)-2,5-piperazinedione (5) showed weak inhibitory activity against α-glucosidase, respectively.