| 초록 |
The most commonly employed bioorthogonal reactions with azides have provided the useful tools for new innovations in biology. They are the Staudinger ligation with phosphine probes, and the copper (I)-catalyzed cycloaddition with terminal alkyne probes (click chemistry). More recently copper-free click chemistry has been developed. Unlike the conventional click chemistry labeling method, this new method does not require a cytotoxic metal catalyst because alkyne is highly strained enough to promote rapid cycloaddition with azide to form a stable triazole conjugate. This Cu-free click chemistry has been rapidly applied in a variety of biological system. Here, we report that the strained cyclooctyne compound is highly reactive to free thiol group as it is reactive to azido group. Therefore, free thiol group should be blocked before this reagent is applied to the biological system. |
