The Carbonic anhydrase (CA) family of hydrolytic Zn(II) metalloenzymes are ubiquitous to all eukaryotic and prokaryotic cells.[1] For decades, aryl sulfonamides have been a mainstay of clinical intervention as antibacterial agents, but only more recently have sulfonamide CA inhibitors been investigated for their anti-cancer and anti-glaucoma activities.[1,2] Recently, Supuran and coworkers have synthesized and evaluated the activity of a series of ߭glycosyl sulfonamides as topical anti-glaucoma agents in rabbit models with high intra ocular pressures (IOP).[2] Within this study, we have developed a new class of hydrophilic aryl sulfonamides with potential anti-glaucoma activity using the in situ click chemistry approach.[3] Screening of the library was achieved using a flouresent DNSA assay, as well as in situ in the presence of the enzyme using a bioaffinity characterization mass spectrometry (BACMS) methodology.[4] Inhibition constants (Ki's) were found to be in the mid to low nM range for bCAII, comparable to the in vitro activity of current treatments of glaucoma.