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Updated: Jun 20, 2025

Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase
Published on: November 23, 2016
Design, synthesis and activity evaluation of usnic acid monoesterification derivatives
Qing Zhang1, Jun-Li He1, Xiao-Xia Zhuo1
1School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin, China.
Abstract:
A new series of usnic acid (UA) monoesterified derivatives 2-15 were designed and synthesised using UA (1) as starting material. The structural characterisation of all compounds was elucidated using 1H-NMR and 13C-NMR spectral data. In vitro studies demonstrated thatmost UA derivatives exhibited higher inhibitory activity against Candida albicans and Staphylococcus aureus. Among them, compound 7 displayed the highest inhibitory activity against C. albicans with a minimum inhibitory concentration (MIC) of 32 μg/mL. Compounds 5, 8, 9, 11and 13 demonstrated superior inhibition of S. aureus (MIC, 16 μg/mL) and biofilm formation in a concentration-dependent manner. With the exception of 11, compounds 5, 8, 9 and 13 were all more effective than UA in inhibiting S. aureus biofilms. This research highlights the potential of UA monoesterified derivatives for the development of dual antimicrobial and antibiofilm agents.
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