A series of bisphenol, bromophenol, and methoxyphenol derivatives (2-24) including the natural bromophenols vidalol B, 3,4,6-tribromo-5-(2,5-dibromo-3,4-dihydroxybenzyl)benzene-1,2-diol (2) and 5,5'-methylenebis(3,4,6-tribromo-benzene-1,2-diol) (3) were prepared. In the current study, inhibition of four human carbonic anhydrase (hCA, EC 4.2.1.1) isozymes, I, II, IV, and VI, with these compounds 2-24 was investigated. The compounds 2-24 were found to be promising carbonic anhydrase inhibitors, some of which showed interesting inhibitory activities. Some of the compounds investigated here showed effective hCA inhibitory activity, and might be used as leads for generating novel carbonic anhydrase inhibitors which are valuable drug candidates for the treatment of glaucoma, epilepsy, gastric and duodenal ulcers, neurological disorders, and osteoporosis.