A series of complex stilbene dimers have been generated through biotransformation of
resveratrol, pterostilbene, and the mixture of both using the enzymatic secretome of
Botrytis cinerea Pers. The process starts with achiral molecules and results in the
generation of complex molecules with multiple chiral carbons. So far, we have been
studying these compounds in the form of enantiomeric mixtures. In the present study, we
isolated the enantiomers to determine their absolute configuration and assess if the
stereochemistry could impact their biological properties. Eight compounds were
selected for this study, corresponding to the main scaffolds generated (pallidol,
leachianol, restrytisol and acyclic dimers) and the most active compounds (trans-δ-
viniferin derivatives) against a methicillin-resistant strain of Staphylococcus aureus
(MRSA). To isolate these enantiomers and determine their absolute configuration, a
chiral HPLC-PDA analysis was performed. The analysis was achieved on a highperformance
liquid chromatography system equipped with a chiral column. For each
compound, the corresponding enantiomeric pair was obtained with high purity. The
absolute configuration of each enantiomer was determined by comparison of
experimental and calculated electronic circular dichroism (ECD). The antibacterial
activities of the four trans-δ-viniferin derivatives against two S. aureus strains were
evaluated.