title: Peptide release upon photoconversion of 2-nitrobenzyl compounds into nitroso derivatives.
abstract: The photoinduced conversion via the aci-nitro into the nitroso form was studied for 4,5-dimethoxy-2-nitrobenzyl alcohols attached to various leaving groups: amino acids histidine (NHis) and aspartate (NAsp) as well as their fluorenylmethoxycarbonyl derivatives (FHis) and (FAsp). In addition, two peptides containing either of the two amino acids were studied, carrying the photoreactive group attached to a histidine (PHis), or to an aspartate (PAsp). The aci-nitro forms with maximum at λ(aci) = 420 nm were observed for FHis and FAsp after the decay of a triplet-triplet absorption, analogous to those of other 2-nitrobenzyl type compounds. For both FHis and FAsp the quantum yield of photoconversion Φ(p) is 0.03 and for the peptides PHis and PAsp ca 0.01 and 0.005, respectively.
authors.affiliation: Max-Planck-Institut für Bioanorganische Chemie, Mülheim an der Ruhr, Germany.
authors.forename: Koji
authors.initials: K
authors.lastname: Nakayama
authors.forename: Inge
authors.initials: I
authors.lastname: Heise
authors.forename: Helmut
authors.initials: H
authors.lastname: Görner
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Gärtner
mesh_terms: D000438:Alcohols / Q000737:chemistry*; D001224:Aspartic Acid / Q000737:chemistry* / Q000378:metabolism; D006639:Histidine / Q000737:chemistry* / Q000378:metabolism; D007700:Kinetics; D018716:Molecular Mimicry; D015394:Molecular Structure; D009578:Nitrobenzenes / Q000737:chemistry*; D009603:Nitroso Compounds / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry; D010782:Photolysis / Q000528:radiation effects*; D011789:Quantum Theory; D060327:Solid-Phase Synthesis Techniques; D014466:Ultraviolet Rays
chemical_list: D000438:Alcohols; D009578:Nitrobenzenes; D009603:Nitroso Compounds; D010455:Peptides; D001224:Aspartic Acid; D006639:Histidine