BI-3663 is a highly selective PTK2/FAK PROTAC, with cereblon ligands to hijack E3 ligases for PTK2 degradation. BI-3663 inhibits PTK2 with an IC50 of 18 nM. BI-3663 is a PROTAC that composes of BI-4464 linked to Pomalidomide with a linker[1]. Anti-cancer

N3-PEG3-CH2CH2COOH, a PEG-based PROTAC linker, is utilized in the synthesis of BI-3663, BI-4216, and BI-0319. Additionally, Azido-PEG3-acid, a non-cleavable 3-unit PEG ADC linker, is employed in the synthesis of antibody-drug conjugates (ADCs).

Tos-PEG4-t-butyl ester (Tos-PEG4-Boc) is a PROTAC linker characterized by its PEG composition. This compound plays a crucial role in the synthesis of a range of PROTACs, including BI-3663, a highly selective PTK2/FAK PROTAC. It employs cereblon ligands to target E3 ligases for the degradation of PTK2, exhibiting potent inhibitory activity with an IC50 of 18 nM[1].