BocNH-PEG-Val-Cit-PAB-PNP

tert-butoxycarbonyl-protected amino-functionalized discrete poly(ethylene glycol)-valyl-citrulline-p-aminobenzyl p-nitrophenyl carbonate (BocNH-PEG-Val-Cit-PAB-PNP) is an ADC linker intermediate containing a defined-length PEG spacer. It contains a Boc-protected amine reactive terminus and a valine–citrulline dipeptide. Discrete chain lengths with different degrees of polymerization are available. Boc protection separates amine reactions from other synthetic steps. Appropriate deprotection exposes a primary amine for subsequent conjugation. The valine–citrulline dipeptide provides a sequence variable for studies of protease-cleavable linkers. The PAB spacer links peptide cleavage to the subsequent self-immolation process. The PNP-activated terminus can be further coupled to suitable amine-containing payloads.

Customization available.