Carborane-Based Carbonic Anhydrase Inhibitors: Insight into CAII/CAIX Specificity from a High-Resolution Crystal Structure, Modeling, and Quantum Chemical Calculations
(a) Structural formulas of 2 and 3. (b) Interactions of 2 and 3 with the CAII active site. Compound 2 is represented with golden carbon atoms, while the carbon atoms of 3 are colored turquoise. Surface of residues making contacts with the isoquinoline moiety of 2 and 3 are highlighted in yellow and blue, respectively. Surface of residues colored orange make contacts with both compounds. Atoms involved in contacts with the sulfonamide groups are not highlighted. (c) Interactions of 1 with the CAII active site. Surface of residues making contacts with the carborane and linker moiety of 1 are highlighted in green. Atoms involved in contacts with the sulfonamide groups are not highlighted. (d) Superposition of binding poses of 1, 2, and 3 in the CAII active site. Superposition of the complex structures was based on the best fit for Cα atoms of CAII residues 6–261.