15770-19-1Relevant articles and documents
Induction of wavelength-dependent photochemistry in bilirubins by serum albumin
McDonagh, Antony F.,Agati, Giovanni,Lightner, David A.
, p. 649 - 660 (2007/10/03)
Quantum yields for Z ? E photoisomerization of the natural bi-chromophore bilirubin IXα in ammoniacal methanol solution were found to vary with excitation wavelength, whereas no variation (within experimental error) was observed for xanthobilirubic acid and for symmetrically substituted bilirubins (bilirubin IIIα, bilirubin XIIIα, and mesobilirubin XIIα) in the same solvent. The quantum yield for Z ? E photoisomerization of xanthobilirubic acid bound to human serum albumin was also invariant with excitation wavelength. In contrast, quantum yields for Z ? E photoisomerization of the symmetrically-substituted bilirubins did show marked excitation wavelength dependency when they were bound to human serum albumin. These results show that quantum yields for Z ? E photoisomerization of bilirubins are markedly sensitive to protein binding and to the nature of pyrrole ring β-substituents. They also demonstrate that wavelength-dependent photochemistry is characteristic of bilirubins with non-identical pyrromethenone chromophores, as expected from exciton coupling theory, and that complexation with albumin induces wavelength-dependent photochemistry in symmetrically substituted bilirubins.
POLYMER BOUND PYRROLE COMPOUNDS- II. SYNTHESIS AND PROPERTIES OF POLYSTYRENE-BOUND LINEAR TETRAPYRROLE PIGMENTS AND RELATED 5(1H)-PYRROMETHENONES
Castan, Pilar,Giralt, Ernest,Perez, Juan C.,Ribo, Josef M.,Siscart, Nuria,Trull, Francesc R.
, p. 2593 - 2608 (2007/10/02)
The title chromophores have been reversibly and covalently attached to differently functionalized polystyrenes including the α-poly(styrene-co-divinylbenzene), and its desnitro derivate.The influence on the reaction
Xanthobilirubic Acid and Its Amides. Synthesis, Spectroscopy, and Solution Structures
Lightner, D. A.,Ma, J.-S.,Adams, T. C.,Franklin, R. W.,Landen, G. L.
, p. 139 - 144 (2007/10/02)
Xanthobilirubic acid, 5--2,4-dimethyl-1H-pyrrol-3-propanoic acid, its methyl ester, amide, N-methylamide and dimethylamide, and kryptopyrromethenone have been synthesized and characterized spectroscopically.In d6-DMSO solution all pyrromethenones were monomeric, with lactam and pyrrole N-Hs H-bonded to solvent.In deuteriochloroform, the pyrromethenones preferred a dimeric form, with intramolecular H-bonding between the lactam C=O of one unit and the lactam and pyrrole N-Hs of the second.
ON THE ROLE OF SINGLET OXIGEN IN THE SELF-SENSITIZED PHOTO-OXYGENATION OF BILIRUBIN AND ITS PYRROMETHENONE MODELS
Landen, G. L.,Park, Y. -T.,Lightner, D. A.
, p. 1893 - 1908 (2007/10/02)
4-Ethyl-3-methyl-5-(4-ethyl-3,5-dimethylpyrrolyl-2-methylidene)-3-pyrrolin-2-one (1), 3,4-diethyl-5-(4-ethyl-3,5-dimethylpyrrolyl-2-methylidene)-3-pyrrolin-2-one (2) and xanthobilirubinic acid (XBR) undergo self-sensitized photo-oxygenation, as does bilirubin.The reaction products of 1 consist of methylethylmaleimide, kryptopyrrole aldehyde and its photo-oxygenation product and oxygenated dipyrroles.The same products are formed from 2, except xeronimide is found instead of methylethylmaleimide.Kinetic studies indicate that singlet oxygen is not necessarily involved in the photo-oxygenation reactions.Geometric photoisomerization (ZE) of 1 and 2, and XBR proceeds at an even faster rate than photosensitized oxygenation.
