Mal-PEG1-Val-Cit-PABC-OH

• CAT Number: I016312
• CAS Number: 2055041-37-5
• Molecular Formula: C27H38N6O8
• Molecular Weight: 574.63
• Purity: ≥95%
• Synonyms: (2S)-5-(carbamoylamino)-2-[N-[(2S)-2-[3-[2-(2,5-dioxopyrrol-1-yl)ethoxy]propanoylamino]-3-methylbutanoyl]-4-(hydroxymethyl)anilino]pentanamide
• InChI: InChI=1S/C27H38N6O8/c1-17(2)24(31-21(35)11-14-41-15-13-32-22(36)9-10-23(32)37)26(39)33(19-7-5-18(16-34)6-8-19)20(25(28)38)4-3-12-30-27(29)40/h5-10,17,20,24,34H,3-4,11-16H2,1-2H3,(H2,28,38)(H,31,35)(H3,29,30,40)/t20-,24-/m0/s1
• InChIKey: GAMNLBAYJPQHKS-RDPSFJRHSA-N
• SMILES: CC(C)C(C(=O)N(C1=CC=C(C=C1)CO)C(CCCNC(=O)N)C(=O)N)NC(=O)CCOCCN2C(=O)C=CC2=O

Mal-PEG1-Val-Cit-PABC-OH(CAT: I016312) is a heterobifunctional PEG-based linker containing a maleimide group, a short PEG1 spacer, and the cleavable Val-Cit-PABC (valine–citrulline–p-aminobenzyloxycarbonyl) moiety. The maleimide functionality enables selective conjugation to thiol-containing biomolecules, forming stable thioether linkages. The Val-Cit-PABC segment is a cathepsin B–sensitive dipeptide linker commonly used in antibody–drug conjugates (ADCs), where enzymatic cleavage triggers self-immolative release of the attached payload. The PEG1 spacer enhances solubility and provides minimal flexibility without excessive spacing. This reagent is widely applied in the design of targeted drug delivery systems, particularly in ADC development, as well as in bioconjugation and chemical biology research.