Bioassay-Guided Isolation of Hepatoprotective Lignans from Vernonia cinerea: DeepSAT-Driven Structural Elucidation and Predictive Mechanistic Insights Against Drug-Induced Liver Injury

Abstract

Three new dibenzylbutane lignans, vernolignans A−C (1−3), along with three known compounds (4−6), were isolated from Vernonia cinerea through a bioactivity-guided isolation process. The planar structures of the new compounds (1−3) were elucidated through comprehensive analysis of HR-ESI-MS, 1D/2D NMR data, with the assistance of AI-based structure annotation tool DeepSAT. The absolute configurations of 1-3 were determined by comparing the experimental and calculated ECD spectra. Compounds 2 and 3 exhibited significant improvements in cell viability and attenuated acetaminophen-induced alanine aminotransferase levels in murine hepatocytes at 20 μM. Bioinformatics analysis and molecular docking suggested that BRAF might be a potential target for these lignans.