Name: Fluorescein-PEG5-acid
Brand: BOC Sciences
Rating: 5 (1 reviews)

Size

Price

Stock

Quantity

$--

In stock

Purity

98%

Solubility

Water, DMSO, DMF, DCM

Storage

Please store the product under the recommended conditions in the Certificate of Analysis.

Shipping

Room temperature in continental US; may vary elsewhere.

IUPACName

3-[2-[2-[2-[2-[2-[(3',6'-dihydroxy-3-oxospiro[2-benzofuran-1,9'-xanthene]-5-yl)carbamothioylamino]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid

Synonyms

1-((3',6'-Dihydroxy-3-oxo-3H-spiro[isobenzofuran-1,9'-xanthen]-5-yl)amino)-1-thioxo-5,8,11,14,17-pentaoxa-2-azaicosan-20-oic acid; 1-[({3',6'-dihydroxy-3-oxo-3H-spiro[2-benzofuran-1,9'-xanthen]-5-yl}carbamothioyl)amino]-3,6,9,12,15-pentaoxaoctadecan-18-oic acid

Excitation

494

Emission

517

InChI Key

CYVBKXKXVSETJX-UHFFFAOYSA-N

InChI

InChI=1S/C34H38N2O12S/c37-23-2-5-27-29(20-23)47-30-21-24(38)3-6-28(30)34(27)26-4-1-22(19-25(26)32(41)48-34)36-33(49)35-8-10-43-12-14-45-16-18-46-17-15-44-13-11-42-9-7-31(39)40/h1-6,19-21,37-38H,7-18H2,(H,39,40)(H2,35,36,49)

SMILES

C1=CC2=C(C=C1NC(=S)NCCOCCOCCOCCOCCOCCC(=O)O)C(=O)OC23C4=C(C=C(C=C4)O)OC5=C3C=CC(=C5)O

Fluorescein-PEG5-acid is a PEG-based linker incorporating a fluorescein scaffold, designed to support targeted protein degradation workflows by enabling robust conjugation handles and improved physicochemical performance in PROTAC constructs. Its flexible poly(ethylene glycol) segment can help modulate linker reach and solubility, while the fluorescein motif provides an intrinsic optical reporter for monitoring synthesis and studying conjugate behavior. The points below describe its structure and practical reactivity considerations in PROTAC assembly.

Structure: The molecule contains a fluorescein core linked to a PEG chain terminating in a carboxylic acid. It features aromatic ring systems, ether linkages within the PEG segment, and an acid-functional group capable of forming stable amide derivatives. Overall, it combines hydrophilicity with a conjugation-ready handle.

Reactivity: The terminal carboxylic acid is suitable for standard PROTAC linker coupling strategies that form amide bonds with amine-bearing ligands or warheads. Typical approaches use carboxyl-activation chemistry (for example, carbodiimide-mediated coupling or activated ester formation) under mild conditions compatible with heteroaromatic fluorescein. Common solvents include polar aprotic media, and base is selected to promote nucleophilic acyl substitution without degrading the fluorophore.

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* 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