A New Hopantenic Acid Derivative from the Rhizomes of Heterosmilax japonica

A new hopantenic acid derivative, (R)-methyl-4-(2,4-dihydroxy-3,3-dimethylbutanamido)butanoate (1), was isolated from the rhizomes of Heterosmilax japonica Kunth, together with three known compounds, (3S)-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (2), daucosterol (3), and ethyl-β-D-xylobioside (4). The structure of 1 was determined by extensive spectroscopic analyses, including 1D and 2D NMR and HR-ESI-MS. Compounds 2 and 4 are new for the genus Heterosmilax.