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Updated: May 31, 2026

Nitropeptide Profiling and Identification Illustrated by Angiotensin II
Published on: June 16, 2019
Peptide release upon photoconversion of 2-nitrobenzyl compounds into nitroso derivatives
Koji Nakayama1, Inge Heise, Helmut Görner
1Max-Planck-Institut für Bioanorganische Chemie, Mülheim an der Ruhr, Germany.
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.
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