Purity ~98% (HPLC). A cell permeable benzenesulfonamide Carbonic Anhydrase (CA) inhibitor that is selective for human hCA IX and hCA XII (Ki = 0.9nM and 5.7nM, respectively) against two other physiologically relevant hCA isoforms (Ki = 23.4nM and 15nM for hCA I and hCA II, respectively), as compared with another CA inhibitor AAZ (Ki = 250nM, 12nM, 25nM, and 5.7nM for hCA I, hCA II, hCA IX, and hCA XII, respectively). It is shown to effectively inhibit the formation of metastases by 4T1 breast cancer cells in a mouse model dose-dependently at pharmacologic concentrations of 15-45mg/kg. Formula: C13H12N4O5S Molecular Weight: 336.3 Solubility: DMSO (50mg/ml)