Cycloaddition reactions involving tetrazines have proven to be powerful bioorthogonal tools for various applications. Conceivably, sequential and selective labeling using tetrazine-based reactions can be achieved by tuning the reaction rate. By varying the substituents on tetrazines, cycloaddition rate variations of over 200 fold have been achieved with the same dienophile. Upon coupling with different dienophiles, such as norbornene, the reaction rate difference can be over 14 000 fold. These substituted tetrazines can be very useful for selective labeling under different conditions.
涉及四氮杂环的环加成反应已被证明是多种应用的强大
生物正交工具。可以想象,通过调整反应速率,可以实现基于四氮杂环的顺序和选择性标记。通过改变四氮杂环上的取代基,已实现与相同的二烯亲和体相比超过200倍的环加成速率变化。与不同的二烯亲和体(如诺尔本烯)耦合时,反应速率差异可超过14,000倍。这些取代的四氮杂环在不同条件下的选择性标记中非常有用。