Fmoc-PEG4-Ala-Ala-Asn-PAB

• CAT Number: I016632
• CAS Number: 2055048-57-0
• Molecular Formula: C43H55N5O13
• Molecular Weight: 849.92
• Purity: ≥95%
• Synonyms: (3S)-3-[[(2S)-2-[[(2S)-2-[3-[2-[2-[2-[2-(9H-fluoren-9-ylmethoxycarbonylamino)ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]propanoyl]amino]propanoyl]amino]-4-[4-(hydroxymethyl)anilino]-4-oxobutanoic acid
• InChI: InChI=1S/C43H55N5O13/c1-28(40(53)46-29(2)41(54)48-37(25-39(51)52)42(55)47-31-13-11-30(26-49)12-14-31)45-38(50)15-17-57-19-21-59-23-24-60-22-20-58-18-16-44-43(56)61-27-36-34-9-5-3-7-32(34)33-8-4-6-10-35(33)36/h3-14,28-29,36-37,49H,15-27H2,1-2H3,(H,44,56)(H,45,50)(H,46,53)(H,47,55)(H,48,54)(H,51,52)/t28-,29-,37-/m0/s1
• InChIKey: DUAREHDODGOEJG-PBCNQIPESA-N
• SMILES: CC(C(=O)NC(C)C(=O)NC(CC(=O)O)C(=O)NC1=CC=C(C=C1)CO)NC(=O)CCOCCOCCOCCOCCNC(=O)OCC2C3=CC=CC=C3C4=CC=CC=C24

Fmoc-PEG4-Ala-Ala-Asn-PAB(CAT: I016632) is a cleavable linker building block designed for antibody–drug conjugate (ADC) and prodrug development. It features an Fmoc-protected amine for solid-phase synthesis, a hydrophilic PEG4 spacer to enhance solubility and flexibility, and an Ala-Ala-Asn tripeptide sequence that serves as an enzymatically cleavable linker. The para-aminobenzyl (PAB) self-immolative spacer ensures efficient release of attached payloads following enzymatic cleavage. This modular design allows researchers to introduce controlled, enzyme-sensitive drug release mechanisms into bioconjugates. Fmoc-PEG4-Ala-Ala-Asn-PAB is widely applied in targeted drug delivery, ADC research, and chemical biology, where precision and stability are essential.