A chemically revertible bioconjugation strategy featuring a new bioorthogonal dissociative reaction employing enamine N-oxides is described. The reaction is rapid, complete, directional, and traceless and displays a broad substrate scope. Reaction rates for the cleavage of fluorophores from proteins are on the order of 82 M⁻¹s⁻¹, and the reaction is relatively insensitive to common aqueous buffers and pHs between 4 and 10. Diboron reagents with bidentate and tridentate ligands also effectively reduce the enamine N-oxide to induce dissociation and compound release. This reaction can be paired with the corresponding bioorthogonal hydroamination reaction to afford an integrated system of bioorthogonal click and release via an enamine N-oxide linchpin with a minimal footprint. The tandem associative and dissociative reactions are useful for the transient attachment of proteins and small molecules with access to a discrete, isolable intermediate. We demonstrate the effectiveness of this revertible transformation on cells by using chemically cleavable antibody-drug conjugates.

描述了一种化学可逆生物共轭策略，其特征是采用烯胺N-氧化物的新型生物正交解离反应。反应快速、完全、定向、无痕，底物范围广泛。从蛋白质上裂解荧光团的反应速率约为 82 M ^-1 s ^-1，并且该反应对常见的水性缓冲液和 4 至 10 之间的 pH 值相对不敏感。具有二齿和三齿配体的二硼试剂也能有效降低烯胺N-氧化物诱导解离和化合物释放。该反应可以与相应的生物正交加氢胺化反应配对，以提供生物正交点击和通过烯胺N-氧化物关键以最小足迹释放的集成系统。串联缔合和解离反应可用于蛋白质和小分子的瞬时附着，并获得离散的、可分离的中间体。我们通过使用化学可裂解的抗体-药物缀合物证明了这种可逆转化对细胞的有效性。