The common types of linkers used for the design of PROTACs

Flexible linkers (n, m = 0, 1, 2, 3, 4, etc.)Relatively rigid linkersClick chemistry based linkers

alkane

piperidine/benzene

triazole

alkyne-alkane

triazole-PEG

PEG

benzene

(CLIPTAC)

PEG-alkane

amide

azobenzene (photoswitchable)