hCAI II-IN-2 (compound 2b) is a highly effective dual inhibitor of human carbonic anhydrase I and II (hCA I II), with Ki values of 40.97 nM, 15.15 nM, and 61.88 nM for hCA I, hCA II, and hCA IX, respectively. With its anti-hypoxic properties, hCAI II-IN-2 demonstrates activity against acute mountain sickness (AMS). Furthermore, this compound exhibits low cellular activity [1].