Stereo- and regioselective azide/alkyne cycloadditions in carbonic anhydrase II via tethering, monitored by
Johannes Schulze Wischeler1, Dong Sun, Nicola U Sandner
1Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032 Marburg, Germany.
Abstract:
The carbonic anhydrase II mutant His64Cys was prepared and applied to tethered alkyne/azide cycloaddition reactions. The azide component could be tethered to the enzyme surface through a disulfide bridge, while the alkyne component was reversibly coordinated through a sulfonamide anchor to the zinc ion in the original catalytic center of the enzyme. The incipient orientation of the reactants in the binding site and of the formed triazole product were characterized by crystallography. The reaction progression could be monitored by HPLC-MS analysis.
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