Thioesterification via Activation of C-Terminal Carboxylic Acids

A second straightforward thioesterification method employs simple condensation conditions of the C-terminal carboxylic acid and thiols by using benzotriazol-l-yl-oxytripyrrolidinophosphonium hexafluorophosphate (PyBOP) or other condensation 

SCHEME 113 Synthesis of glycopeptide-athioesters by (a) using safety-catch linker and (b) thioesterification of activated C-terminal carboxylic acids. Boc, ferf-butoxycarbonyl. 

---