• CAS No.：
  756526-06-4
• Synonyms：
  Amino-PEG8-t-butyl ester;H2N-PEG8-tBu;Amino-PEG8-Boc
• Purity：
  ≥95%
• Molecular formula：
  C₂₃H₄₇NO₁₀
• Molecular weight：
  497.6
• Uses：
  Applicated in medical research, drug-release, nanotechnology and new materials research, cell culture. In the study of ligand, polypeptide synthesis support, a graft polymer compounds, new materials, and polyethylene glycol-modified functional coatings and other aspects of the active compound.

NH2-PEG8-CH2CH2COOtBu (Amino-PEG8-t-butyl ester) is a bifunctional polyethylene glycol (PEG) derivative featuring a primary amine at one end and a tert-butyl-protected carboxyl group at the other. The Boc protection keeps the carboxylate inert during early steps of conjugation, while the amine terminus provides a versatile handle for attaching to drugs, peptides, antibodies, or other biomolecules.

Applications:

● ADC linkers — as a hydrophilic spacer between antibody and cytotoxic payload to improve payload solubility, reduce aggregation, and tune drug-to-antibody ratio (DAR) and PK. 
● PROTAC linkers / targeted-degradation molecules — PEG8 is a common length for balancing flexibility and cell permeability in PROTACs. 
● Peptide/protein conjugation and bioconjugation intermediates — the free amine on one end and a protected carboxyl on the other make it convenient for stepwise synthesis (Boc/t-Bu protectable). Useful in linker design for small-molecule conjugates, imaging agents, etc. 

Huateng Pharma can provide NH2-PEG8-CH2CH2COOtBu from grams to 100 kilograms, contact at sales@huatengusa.com for mor details.