A New Succinate Derivative from Ajuga decumbens.

A new succinate derivative, ethyl (5-formylfuran-2-yl)methyl succinate (1), along with three known compounds (2-4) have been isolated from the whole plants of Ajuga decumbens Thunb. Their structures were elucidated by extensive spectroscopic (1D and 2D NMR) and HR-ESI-MS data analysis, and literature values. Compound 1 was isolated as a new succinate derivative, and compounds 2 and 3 were for the first time separated from A. decumbens.