TCO-PEG-Ala-Ala-Asn-PAB-OH

Trans-cyclooctene-functionalized discrete poly(ethylene glycol)-alanyl-alanyl-asparagine-p-aminobenzyl alcohol (TCO-PEG-Ala-Ala-Asn-PAB-OH) is an ADC linker intermediate containing a defined-length PEG spacer. It contains a trans-cyclooctene (TCO) reactive terminus and an alanine–alanine–asparagine tripeptide. Discrete chain lengths with different degrees of polymerization are available. Trans-cyclooctene can pair with tetrazines in inverse-electron-demand Diels–Alder reactions for assembly of bioorthogonal modules. The alanine–alanine–asparagine tripeptide provides a sequence variable for studies of protease-cleavable linkers. The PAB spacer links peptide cleavage to the subsequent self-immolation process. The PAB hydroxyl group retains a synthetic handle for subsequent activation and payload derivatization.

Customization available.