Amino acid bioconjugation via iClick reaction of an oxanorbornadiene-masked alkyne with a Mn~Ⅰ(bpy)(CO)_3-coordinated azide

摘要

The catalyst-free room temperature iClick reaction of an unsymme-trically 2,3-disubstituted oxanorbornadiene (OND) as a "masked" alkyne equivalent with [Mn(N_3)(bpy~(CH_3,CH_3))(CO)_3] leads to isolation of a phenylalanine ester bioconjugate, in which the model amino acid is linked to the metal moiety via a N-2-coordinated triazolate formed in a cycloaddition-retro-Diels-Alder (crDA) reaction sequence, in a novel approach to bioorthogonal coupling reactions based on metal-centered reactivity.