Laccase-Catalyzed Biotransformation of Dihydrostilbenes and Phenanthrenes: A Route to Novel Natural Product Derivatives.

Biotransformation is an eco-friendly and effective strategy for enhancing the chemical diversity of natural products for biological screening. Among various biotransformation methods, laccase-mediated transformations have successfully yielded bioactive compounds across multiple chemical classes. In this study, laccases from Trametes versicolor were used to catalyze the biotransformation of the dihydrostilbene gigantol and the phenanthrenes flavidin and coleonin, leading to the formation of a series of structurally complex derivatives. The selected substrates were subjected to laccase-mediated biotransformation and the reactions were followed using state-of-the-art analytical techniques. Depending on the reaction conditions, the process led to the formation of multiple monomers, dimers and trimers. After optimization and scale-up of the biotransformation reactions, the crude mixtures were purified by high-resolution semipreparative HPLC using dry-load injection. This workflow enabled the isolation of 13 structurally diverse derivatives, with 10 compounds being reported for the first time. All products were comprehensively characterized using high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy. This study underscores the promising potential of fungal laccase-mediated biotransformation as a tool to diversify bioactive natural product structures, thereby generating novel scaffolds of interest for biological screening campaigns.