23-Azido-3,6,9,12,15,18,21-heptaoxatricosan-1-amine
Molecular Formula: C16H34N4O7
CAS#: 1333154-77-0
SMILES: NCCOCCOCCOCCOCCOCCOCCOCCN=[N+]=[N-]
MDL#: MFCD13185016
Catalog#: AMTGC352-AA17
Molecular weight: 394.46 g/mol
Appearance: Colorless liquid
Purity: 97.5%
Storage: Long-term storage in a freezer at -20 °C
Solubility: Dichloromethane, Chloroform, Methanol
Other names:
- N3-PEG7-CH2CH2NH2
- Azido-PEG7-amine
- N3-PEG7-NH2
- NH2-PEG7-N3
- Azido-dPEG7-amine
Fields of Interest
Click chemistry, bioconjugation, chemical biology, medicinal chemistry, drug delivery, PROTAC development, ADC linker development, biomaterials, polymer modification, surface functionalization, molecular linker synthesis, specialty chemical synthesis
Background
23-Azido-3,6,9,12,15,18,21-heptaoxatricosan-1-amine (CAS 1333154-77-0) is a heterobifunctional PEG7 linker containing a terminal azide (N₃) and a terminal primary amine (NH₂). The extended polyethylene glycol spacer provides flexibility, hydrophilic character, and controlled molecular separation between the two reactive termini.
The azide provides a bioorthogonal handle for copper-catalyzed azide–alkyne cycloaddition (CuAAC) and strain-promoted azide–alkyne cycloaddition (SPAAC), while the primary amine provides a complementary site for reactions with carboxylic acids, activated esters such as NHS esters, isocyanates, and other amine-reactive functionalities. This combination of orthogonal functional groups makes Azido-PEG7-amine a versatile building block within a comprehensive portfolio of functionalized PEGs for modular molecular assembly.
Applications
Azido-PEG7-amine is useful in bioconjugation, click chemistry, chemical biology, drug delivery, PROTAC and ADC research, biomaterials, and specialty chemical synthesis. The primary amine can be used to attach the PEG spacer to proteins, peptides, small molecules, polymers, surfaces, or other appropriately activated substrates while retaining the azide for subsequent click chemistry.
Alternatively, the azide can first be conjugated with an alkyne-, DBCO-, or BCN-functionalized component, leaving the primary amine available for a second modification step. The PEG7 spacer provides greater molecular separation than shorter PEG linkers, making it useful when additional distance or hydrophilic character between conjugated components is desirable. Azido-PEG7-amine has also been reported as a linker in the synthesis of bivalent mTOR inhibitors and is commercially classified for use in PROTAC and ADC linker development.
Literature:
- ChemMedChem, 2013, vol. 8, # 3, p. 521 – 526
- European Journal of Medicinal Chemistry, 2026, vol. 305, art. no. 118566
- European Journal of Medicinal Chemistry, 2022, vol. 242, art. no. 114697