BDP 564/570 is a fluorophore with the emission in orange part of the spectrum. The dye is pretty hydrophobic. It can be used for the labeling of lipids, oligonucleotides, peptides, and many other large and small molecules.
Free carboxylic acid can be used in peptide synthesis as an N-terminal monomer. An NHS ester, with a pre-activated carboxy group, is also available.