Fig 3.

Structures of the most active compounds. Compound I, 4-hydroxybenzo[cd]indol-2(1H)-one; compound II, β-oxynaphthoic acid; compound III, 2,3-difluoro-1-naphthoic acid; compound IV, 3-[3-(1,3-benzodioxol-5-yl)prop-2-enoyl]-2-hydroxy-cyclohepta-2,4,6-trien-1-one; compound V, 4-hydroxy-3-methoxy-N-(naphthalen-1-ylmethylideneamino)benzamide; compound VI, 1-(5-ethyl-2,4-dihydroxyphenyl)-2-phenoxyethanone; compound VII, 3′-fluoro-4′-hydroxy-4-biphenylcarboxylic acid; compound VIII, 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid; compound IX, 2′,4′-difluoro-4-hydroxybiphenyl-3-carboxylic acid (diflunisal); compound X, 3-phenyl salicylic acid; compound XI, 4,4′-fluorophenyl benzoic acid.