Microwave-assisted preparation and antimicrobial activity of O-alkylamino benzofurancarboxylates

ABSTRACT A series of derivatives of 2 and 3-benzofurancarboxylates were synthesized under microwave-assisted conditions. Their in-vitro antimicrobial properties were assessed. Inhibition by the compounds of the growth of antibiotic-susceptible standards and clinically isolated strains of Gram-positive and Gram-negative bacteria, yeasts, and a human fungal pathogen was moderate to significant. Methyl 5-bromo-7-[2-(N,N-diethylamino)ethoxy]-6-methoxy-2-benzofurancarboxylate hydrochloride was identified as the most active compound (MIC 3-12 × 10-3 μmol/cm3 against Gram-positive bacteria; MIC 9.4 × 10-2 μmol/cm3 against Candida and Aspergillus brasiliensis). The molecular and crystal structures of 2-(N,N-diethylamino)ethyl 6-acetyl-5-hydroxy-2-methyl-3-benzofurancarboxylate were established by single-crystal X-ray diffraction. GRAPHICAL ABSTRACT .