hCAIX/XII-IN-8 (compound 3g) is a potent inhibitor of the human carbonic anhydrases (CAs) IX and XII, with inhibition constants (K i) of 8.5 nM for CA IX and 6.7 nM for CA XII. It demonstrates significant inhibitory efficacy particularly against tumor-associated, membrane-bound isoforms hCA IX and XII, while exhibiting a high selectivity over the cytosolic isoforms hCA I and II [1].

CA XII (human):6.7 nM (Ki), CA IX (human):8.5 nM (Ki), CA II (human):72.0 nM (Ki), CA (human):5269 nM (Ki)