Occurrence of selected linker motifs in the Maple database of published degrader structures. Wavy lines indicate attachment to other linker motifs, protein-binding ligands, or connecting functional groups. Since many PROTACs combine more than one structural motifs into their linkers therefore these percentages sum to more than 100

Structure Linker motif Occurrence in Maple Database structures (%)
PEG 54
Alkyl 31
Other Glycol 14
Alkyne 7
Triazole 6
Piperazine 4
Piperidine 4