Various 4-bromomethylcoumarins (1a-k) were reacted with methyl salicylate to yield 2-(2-oxo-2H-chromen-4-ylmethoxy)-benzoic acid methyl esters (2a-k). Formations of (3a-k) were achieved by using DBU under microwave irradiation. Structures of all the compounds were established on the basis of their spectral data. All the compounds were tested in vitro for their antimicrobial activity and cell cytotoxicity. All the tested compounds (2b-k) and (3a-k) were shown to be better activity against Staphylococcus aureus than the standard Ciprofloxacin. The compound (3k) (R = 6-OMe) was found to be more potent cytotoxic than the standard 5-fluorouracil. 1. Introduction Benzofuran and its derivatives [1] have attracted considerable interest in recent years for their versatile properties in chemistry and pharmacology. 3-Benzofuran-5-aryl-1-pyrazolylcarbonyl-4-oxo-naphthyridin [2] was found to be the most potent antitubercular agent against Mycobacterium tuberculosis, even better than standard drug isoniazid. Benzofuran derivatives [3] were found to exhibit favorable antibacterial activity against Staphylococcus aureus and Bacillus subtilis which were better than the control drugs Cefotaxime and Ketoconazole. 2-Phenylbenzofurans [4] exhibited enhanced antiprotozoal activity against Trypanosoma brucei rhodesiense and Plasmodium falciparum. 2-Arylbenzofurans [5] were isolated from the roots of Glycyrrhiza uralensis. They showed significant in vitro protein tyrosine phosphate-1B inhibitory activity. Technetium-99m labeled pyridyl benzofuran derivatives [6] was tested as potential probes for imaging β-amyloid plaques in Alzheimer’s brains using single photon emission computed tomography. Coumarin moieties are widely featured in a broad range of pharmacological and biologically active compounds [7, 8]. Phosphorohydrazine derivatives of coumarin displayed high in vivo antitumour activity against P388 leukemia [9]. Coumarin pyrazoline hybrids were found to possess the highest cytotoxicity against colorectal cell line HCT-116 with IC50 value of 0.01？μM [10]. Thiazolyl coumarin derivatives showed significant inhibition against Haemophilus influenzae with a MIC value of 15？μM which is less than that of tetracycline [11]. Benzo[d]thiazolyl coumarins [12] demonstrated anti-HIV activity against HIV-1 cell with EC50 < 7？μg/mL. Based on the survey of recent literature studies on coumarins and benzofurans and in our effort to discover novel antimicrobial [13–16] and anticancer agents [17, 18], the aim of our work is synthesis of 4-(3-hydroxy-benzofuran-2-yl)coumarins and the
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