Metal-free hypervalent iodine-mediated synthesis and biological evaluation of 2-[(3-aryl-isoxazol-5-yl)methoxy)]benzaldehydes

A series of 2-[(3-aryl-isoxazol-5-yl)methoxy]benzaldehydes were synthesized through metal-free hypervalent iodine-mediated [3+2]-cycloaddition between 2-(2-propynyloxy)benzaldehyde and aldoximes. All new products were screened for their antibacterial activity against a number of gram-positive and-negative bacterial strains. Further, antifungal activity of these compounds was also evaluated against C. albicans. 2-[(3-(3-Tolyl-isoxazol-5-yl)methoxy)]benzaldehyde and 2-[(3-(3-fluorophenyl-isoxazol-5-yl)methoxy)benzaldehyde were found to be the most potent amongst all the synthesized compounds. Antioxidant properties were also evaluated by using DPPH radical scavenger method in which 2-[(3-(3-bromophenylisoxazol-5-yl)methoxy)benzaldehyde showed the highest antioxidant activity. All new products were also screened for their in vitro cytotoxicity against mouse fibroblast and plant cell germination cell lines.