Boc-Val-Ala-PAB-PNP

• CAT Number: I016315
• CAS Number: 1884578-00-0
• Molecular Formula: C27H34N4O9
• Molecular Weight: 558.58
• Purity: ≥95%
• Synonyms: [4-[[(2S)-2-[[(2S)-3-methyl-2-[(2-methylpropan-2-yl)oxycarbonylamino]butanoyl]amino]propanoyl]amino]phenyl]methyl (4-nitrophenyl) carbonate
• InChI: InChI=1S/C27H34N4O9/c1-16(2)22(30-25(34)40-27(4,5)6)24(33)28-17(3)23(32)29-19-9-7-18(8-10-19)15-38-26(35)39-21-13-11-20(12-14-21)31(36)37/h7-14,16-17,22H,15H2,1-6H3,(H,28,33)(H,29,32)(H,30,34)/t17-,22-/m0/s1
• InChIKey: PGJUTVVCCBCEIY-JTSKRJEESA-N
• SMILES: CC(C)C(C(=O)NC(C)C(=O)NC1=CC=C(C=C1)COC(=O)OC2=CC=C(C=C2)[N+](=O)[O-])NC(=O)OC(C)(C)C

Boc-Val-Ala-PAB-PNP(CAT: I016315) is a protected, cleavable linker intermediate commonly used in the design of drug delivery systems and prodrugs. It incorporates the Val-Ala dipeptide sequence, a cathepsin-sensitive motif that undergoes enzymatic cleavage in lysosomal environments. The p-aminobenzyl (PAB) group functions as a self-immolative spacer, ensuring efficient release of the attached payload upon cleavage. The para-nitrophenyl carbonate (PNP) ester provides an activated leaving group for coupling with amine- or hydroxyl-containing drugs, while the Boc group serves as a protective functionality, allowing controlled synthetic modifications. This reagent is widely applied in antibody–drug conjugate (ADC) development and targeted therapeutic research.