X-ray crystallographic and kinetic investigations of 6-sulfamoyl-saccharin as a carbonic anhydrase inhibitor.
Alterio, V., Tanc, M., Ivanova, J., Zalubovskis, R., Vozny, I., Monti, S.M., Di Fiore, A., De Simone, G., Supuran, C.T.(2015) Org Biomol Chem 13: 4064-4069
- PubMed: 25733161 
- DOI: https://doi.org/10.1039/c4ob02648a
- Primary Citation of Related Structures:  
4XE1 - PubMed Abstract: 
6-Sulfamoyl-saccharin was investigated as an inhibitor of 11 α-carbonic anhydrase (CA, EC 4.2.1.1) isoforms of human (h) origin, hCA I-XIV, and X-ray crystallographic data were obtained for its adduct with hCA II, the physiologically dominant isoform. This compound possesses two potential zinc-binding groups, the primary sulfamoyl one and the secondary, acylatedsulfonamide. Saccharin itself binds to the Zn(II) ion from the CA active site coordinating with this last group, in deprotonated (SO2N(-)CO) form. Here we explain why 6-sulfamoyl-saccharin, unlike saccharin, binds to the metal ion from the hCA II active site by its primary sulfonamide moiety and not the secondary one as saccharin itself. Our study is useful for shedding new light to the structure-based drug design of isoform-selective CA inhibitors of the sulfonamide type.
Organizational Affiliation: 
Istituto di Biostrutture e Bioimmagini-CNR, via Mezzocannone 16, 80134 Naples, Italy.