Synthesis of novel lignan-like compounds and their antimicrobial activity

Abstract

Herein we report the preparation of 3,4-dibenzylfurans and some oxidized derivatives with lignan backbone. The compounds were prepared using the Friedel-Crafts reaction with BF₃ etherate as catalyst, demethylation with iodocyclohexane, acetylation and oxidation reactions. The antimicrobial activity was evaluated through their capacity to inhibit the growth of Gram positive and Gram negative bacteria, and of the yeast Candida albicans. Among ten products assayed four furans displayed a good antimicrobial activity against Staphylococcus aureus, S. epidermidis and C. albicans; on the contrary, none of the compounds were active against Pseudomonas aeruginosa. One of them inhibited the growth of S. aureus, S. epidermidis (biofilm producer strain) and C. albicans at 16 μg/mL, showing a bactericidal activity already after one hour of treatment. In summary, the results suggest a possible use of these derivatives for general disinfection practices or antimicrobial agents in cosmesis skin-care.

Keywords: 3,4-Dibenzylfurans; Antimicrobial activity; Demethylation; Friedel–Crafts alkylation; Lignans; Oxidation.