Farrell, David P. published the artcileAnion binding by fluorescent Fmoc-protected amino acids, SDS of cas: 17351-61-0, the publication is Supramolecular Chemistry (2016), 28(1-2), 45-52, database is CAplus.
Two non-natural amino acids with fluorescent urea side-chains were prepared from Fmoc-protected aspartic and glutamic acids. In acetonitrile solution, the emission of the Asp derivative is strongly quenched by HCO3– or H2PO4– (K = 104 M-1) but not by less-basic Cl– or NO3–. Solutions containing excess bicarbonate ion appear peach-colored, with gammaabs at 394 and 495 nm ascribed to the anion complex and urea-deprotonated sensor, resp. Corresponding fluorescence bands are observed at 475 and 579 nm. Dihydrogenphosphate is not sufficiently basic to remove H+ from the ground state of the fluorophore. However, deprotonation of the excited state occurs in the presence of>1 equiv of H2PO4–. According to 1H NMR in DMSO-d6, recognition of H2PO4– occurs at the urea N-H groups and the amino acid backbone N-H. DFT techniques further predict that the backbone C = O group accepts an H-bond from the anion. The Glu derivative has lower affinity for anions; the addnl. CH2 group in its side-chain apparently sets the backbone N-H and C = O too far from the urea to contribute significantly to binding. To demonstrate suitability for standard Fmoc-based solid-phase peptide synthesis, the Asp derivative was incorporated into a 12-residue peptide.
Supramolecular Chemistry published new progress about 17351-61-0. 17351-61-0 belongs to catalysis-chemistry, auxiliary class Phase Transfer Catalyst, name is Tetraethylammonium hydrogencarbonate, and the molecular formula is C9H21NO3, SDS of cas: 17351-61-0.
Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia