endo-BCN-PEG4-t-butyl ester

endo-BCN-PEG4-t-butyl ester is a click chemistry linker containing a BCN group and a t-butyl protected carboxyl group. The BCN group can react with azide-tagged molecules. The protected carboxyl group (COOH) prevents self coupling or polymerization under standard acid/amine or acid/hydroxyl coupling conditions. The t-butyl ester can be converted to free acid under acidc condition.