A carbonic anhydrase inhibitor (Kis = 3.5-52 nM for carbonic anhydrase II, V, VI, IX, XII, XIII, and XIV) that is selective for these isoforms over carbonic anhydrase I, III, and IV (Kis = 50, 8, and 8.5 µM, respectively); inhibits carbonic anhydrase in isolated rabbit iris-ciliary body by 87% at 0.02%; reduces intraocular pressure in an α-chymotrypsin-treated rabbit model of ocular hypertension and in normotensive rabbits at 0.5%, applied topically