Bioactive neolignans and lignans from the roots of Paeonia lactiflora.

Two new neolignans and one new lignan (1–3) were obtained from the roots of Paeonia lactiflora. Their structures were unambiguously elucidated based on extensive spectroscopic analysis, single-crystal X-ray crystallography, and the calculated and experimental electronic circular dichroism (ECD) spectra. Compound 1 was a racemic mixture and successfully resolved into the anticipated enantiomers via chiral-phase HPLC. Compound 3 demonstrated moderate inhibitory activity against human carboxylesterase 2A1 (hCES2A1) with an IC 50 value of 7.28 ± 0.94 μmol·⁻¹. [ABSTRACT FROM AUTHOR]