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CAS Number 203866-15-3

Fluorinated Building Blocks, Heterocyclic Building Blocks, Materials, Monomers

Product Code B2521-500mg
Price £70 ex. VAT

A difluorinated l-proline derivative

Used as a molecular scaffold for biochemistry and a conformational tool for polypeptides

Specifications | MSDS | Literature and Reviews

N-Boc-4,4-difluoro-l-proline (CAS number 203866-15-3) is a tert-butoxycarbonyl (Boc) protected l-proline with two fluorine substituents at 4-position. N-Boc-4,4-difluoro-l-proline is an S-enantiomer, making it an excellent additive/catalyst in asymmetric reactions. In protein/peptide chemistry, N-Boc-4,4-difluoro-l-proline is introduced for conformational control favouring 78% cis-conformers. The conformation selectivity is also expressed in the 19F NMR spectrum which is a powerful tool to study the isomerisation of peptides and proteins.

N-Boc-4,4-difluoro-l-proline is also applied as a molecular scaffold for synthesising fibroblast activation protein, a trans-membrane serine protease.

Multiple functional groups

Multiple functional groups

For facile synthesis

Fluorinated building block

Fluorinated l-proline building block

For organic synthesis, medicinal chemistry and biochemistry research

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High purity 203866-15-3

High purity

>97% High purity

General Information

CAS Number 203866-15-3
Chemical Formula C10H15F2NO4
Full Name (S)-1-(tert-Butoxycarbonyl)-4,4-difluoro-2-pyrrolidinecarboxylic acid
Molecular Weight 251.23 g/mol
Synonyms N-(tert-Butoxycarbonyl)-4,4-difluoro-l-proline
Classification / Family Fluorinated building blocks, Heterocyclic building blocks, Proteins, Peptides, Asymmetric synthesis, Chiral molecules

Chemical Structure

N-Boc-4,4-difluoro-L-proline chemical structure, CAS 203866-15-3.
N-Boc-4,4-difluoro-l-proline chemical structure, CAS 203866-15-3

Product Details

Purity 97%
Melting Point Tm = 120 °C – 140 °C
Optical Rotation −44.19 ° (c = 1, methanol)
Appearance Off-white powder

MSDS Documentation

N-Boc-4,4-difluoro-L-proline MSDS SheetN-Boc-4,4-difluoro-l-proline MSDS Sheet

Literature and Reviews

  1. Deciphering the fluorine code—the many hats fluorine wears in a protein environment, A. Berger et al., Acc. Chem. Res., 2017, 50, 2093–2103(2017); DOI: 10.1021/acs.accounts.7b00226.
  2. Minimising conformational bias in fluoroprolines through vicinal difluorination, G.-J. Hofman et al., Chem. Commun., 54, 5118(2018); DOI: 10.1039/c8cc01493k.
  3. Fluorinated prolines as conformational tools and reporters for peptide and protein chemistry, S. Verhoork et al., Biochemistry, 57(43), 6132–6143(2018); DOI: 10.1021/acs.biochem.8b00787.
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