Semisynthesis, characterisation, and antibacterial evaluation of a novel lecanoric acid-derived amide library

• Ethan D. Abbott,
• Sasha Hayes,
• Jonathan M. White,
• Bernd H. A. Rehm and
• Rohan A. Davis

Beilstein J. Org. Chem. 2026, 22, 1023–1032, doi:10.3762/bjoc.22.81

• , The University of Melbourne, Melbourne, VIC 3010, Australia Centre for Cell Factories and Biopolymers, Griffith University, Brisbane, QLD 4111, Australia NatureBank, Griffith University, Brisbane, QLD 4111, Australia 10.3762/bjoc.22.81 Abstract The known lichen depside, lecanoric acid (1), was

• new semisynthetic compounds were fully characterised following 1D/2D NMR, MS and UV data analysis. Crystalline lecanoric acid was obtained during the chemical investigations of the lichen extract, enabling the first X-ray crystallographic analysis to be undertaken on this depside. Compounds 1–13 were

• of biofilm (21% at 50 µM). Keywords: amide; biodiscovery; depside; lecanoric acid; natural products; Parmotrema tinctorum; Pseudomonas aeruginosa; semisynthesis; Introduction Lichens are organisms resulting from the symbiotic relationship between a fungus (the mycobiont) and an alga (the photobiont