Antibacterial activities of halogenated bis(hydroxyphenyl)methanes

Abstract

Biologically active bromophenols were isolated from red alga Odonthalia corymbifera. And a series of modified halophenols was prepared by the reaction of bis(hydroxyphenyl)methanes with effective halogenating agents such as bromine, sulfuryl chloride, and xenon fluoride. One of these compounds, a bromophenol, 2,2',3,3'-tetrabromo-4,4',5,5'-tetrahydroxydiphenylmethane, .frequently isolated from red algae, was synthesized for the first time. Other halophenols included several novel compounds were synthesized from the phenolic intermediates, bis(3,4-dihydroxyphenyl)methane and bis(2-hydroxyphenyl)methane. All of these halophenols were tested for antibacterial activity against three Gram-positive, three Gram-negative bacteria. Of all these halophenols, 3,3',5,5'-tetrachloro-2,2'-dihydroxydiphenylmethane exerted a powerful antibacterial effect against Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus, Proteus vulgaris, and Salmonella typhimurium. The preliminary structure–activity relationship will be described.