(S)-N-Fmoc-2-Thienylalanine

CAS 130309-35-2

Sulfur in an amino acid does not always mean a reactive thiol. In Fmoc-2-thienylalanine, it belongs to a thiophene ring, offering an aromatic replacement for phenylalanine's benzene ring. Researchers can incorporate this residue into a peptide and ask how the changed surface affects molecular organization. A 2010 study investigated self-assembly of a designed thienylalanine-containing peptide in different solvents. Such assembly is distinct from making new peptide bonds: many complete molecules can associate without extending their individual backbones. The sequence and surroundings still matter, so one result is not a universal rule for every peptide containing the residue. This building block makes a precise ring substitution accessible, allowing packing and supramolecular structure to become questions that experiments can answer. Assembly measurements must distinguish ordered structures from simple solution cloudiness.