Name: Fmoc-NH-PEG4-t-butyl ester
Brand: BOC Sciences
Rating: 5 (1 reviews)

Size

Price

Stock

Quantity

$--

In stock

Purity

≥95%

Appearance

Pale Yellow Oily Matter

Storage

Store at 2-8°C

Shipping

Room temperature in continental US; may vary elsewhere.

IUPACName

tert-butyl 3-[2-[2-[2-[2-(9H-fluoren-9-ylmethoxycarbonylamino)ethoxy]ethoxy]ethoxy]ethoxy]propanoate

Synonyms

Fmoc-N-amido-PEG4-t-butyl ester; 5,8,11,14-Tetraoxa-2-azaheptadecanedioic acid, 17-(1,1-dimethylethyl) 1-(9H-fluoren-9-ylmethyl) ester; 2-Methyl-2-propanyl 1-(9H-fluoren-9-yl)-3-oxo-2,7,10,13,16-pentaoxa-4-azanonadecan-19-oate; 2,7,10,13,16-Pentaoxa-4-azanonadecan-19-oic acid, 1-(9H-fluoren-9-yl)-3-oxo-, 1,1-dimethylethyl ester

Boiling Point

666.6±55.0°C at 760 mmHg

Density

1.1±0.1 g/cm3

InChI Key

DRZKEBNWHFGFST-UHFFFAOYSA-N

InChI

InChI=1S/C30H41NO8/c1-30(2,3)39-28(32)12-14-34-16-18-36-20-21-37-19-17-35-15-13-31-29(33)38-22-27-25-10-6-4-8-23(25)24-9-5-7-11-26(24)27/h4-11,27H,12-22H2,1-3H3,(H,31,33)

SMILES

CC(C)(C)OC(=O)CCOCCOCCOCCOCCNC(=O)OCC1C2=CC=CC=C2C3=CC=CC=C13

Fmoc-NH-PEG4-t-butyl ester is a polyethylene glycol-based PROTAC linker building block designed to provide conformational flexibility and improved solubility in linker–ligand conjugates. Its protected carboxylate and Fmoc functionality enable reliable stepwise assembly of bifunctional degraders through orthogonal synthetic handles. The ensuing sections describe the linker’s structural features and practical reactivity considerations for constructing PROTACs in a research setting.

Structure: The linker contains an Fmoc-protected amine and an esterified carboxylate capped with a tert-butyl group, connected through a PEG chain that provides ether-rich, flexible segments. It features aromatic carbamate protection, aliphatic ester linkage, and multiple ether oxygen atoms that support polarity and hydrogen-bonding interactions.

Reactivity: The tert-butyl ester is typically cleaved under acid conditions to reveal a carboxylic acid for amide or other coupling reactions. The Fmoc group can be removed under base to expose an amine for stepwise conjugation. PROTAC assembly commonly employs carbodiimide-mediated couplings in polar aprotic solvents, with appropriate bases and coupling additives to drive amide bond formation while minimizing side reactions.

Stock concentration: *

Desired final volume: *

Desired concentration: *

* Our calculator is based on the following equation:
Concentration (start) x Volume (start) = Concentration (final) x Volume (final)
It is commonly abbreviated as: C₁V₁ = C₂V₂