hCAIX-IN-8 (compound 7i) is a potent and selective hCAIX inhibitor with IC 50 s of 1.99, 0.024, 1.10 µM for CAII, CAIX, CAVA respectively. hCAIX-IN-8 shows anti-proliferation activity with low toxicity. hCAIX-IN-8 decreases the epithelial to mesenchymal transitions and induces apoptosis. hCAIX-IN-8 inhibits cell migration and colonization potential.