• CAS No.：
  186020-66-6
• Synonyms：
  OH-PEG3-TBA
  Hydroxy-PEG3-t-butyl ester
  12-Hydroxy-4,7,10-trioxadodecanoic acid tert-butyl ester
  
• Purity：
  ≥95%
• MF：
  C₁₃H₂₆O₆
• MW：
  278.3
• Recommended Storage Condition：
  Store at -5°C,keep in dry and avoid sunlight.
• 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.

OH-PEG3-CH2CH2COOtBu (Hydroxy-PEG3-t-butyl ester, CAS 186020-66-6) is a short PEG derivative with a hydroxy group and a tert-butyl ester. The PEG3 spacer improves solubility and flexibility, while the tert-butyl ester serves as a removable protecting group that can be converted to the corresponding carboxylic acid.

Applications

Linker in bioconjugation: Used in the preparation of drug-linker systems, such as antibody–drug conjugates (ADCs) and PROTAC.
Intermediate for PEG derivatives: The hydroxy group allows further functionalization (e.g., esterification, etherification), enabling the synthesis of advanced PEGylated compounds.
Drug delivery research: PEG spacers like PEG3 improve solubility, reduce aggregation, and enhance pharmacokinetic profiles.
Medicinal chemistry: Serves as a protected PEG-carboxylate building block for prodrugs, targeted therapies, and polymer–drug conjugates.