endo-BCN-PEG4-NHS ester

• CAT Number: I045941
• CAS Number: 2252422-32-3
• Molecular Formula: C26H38N2O10
• Molecular Weight: 538.59
• Purity: ≥95%
• Synonyms: (2,5-dioxopyrrolidin-1-yl) 3-[2-[2-[2-[2-(9-bicyclo[6.1.0]non-4-ynylmethoxycarbonylamino)ethoxy]ethoxy]ethoxy]ethoxy]propanoate
• InChI: InChI=1S/C26H38N2O10/c29-23-7-8-24(30)28(23)38-25(31)9-11-33-13-15-35-17-18-36-16-14-34-12-10-27-26(32)37-19-22-20-5-3-1-2-4-6-21(20)22/h20-22H,3-19H2,(H,27,32)
• InChIKey: MFQCOKMBYCIQEJ-UHFFFAOYSA-N
• SMILES: C1CC2C(C2COC(=O)NCCOCCOCCOCCOCCC(=O)ON3C(=O)CCC3=O)CCC#C1

endo-BCN-PEG4-NHS ester（Cat No.:I045941）is a heterobifunctional linker engineered for efficient, copper-free click chemistry and biomolecule conjugation. The endo-bicyclononyne (endo-BCN) group enables strain-promoted azide–alkyne cycloaddition (SPAAC), providing rapid, selective, and biocompatible reactions with azides. The NHS ester reacts efficiently with primary amines on proteins, peptides, or polymers, forming stable amide bonds. A PEG4 spacer enhances solubility, reduces steric hindrance, and improves flexibility, ensuring compatibility in complex biological systems. This reagent is widely applied in antibody–drug conjugates, chemical biology research, diagnostic probe development, and targeted delivery strategies requiring high precision and stability.