One- and two-photon time-resolved fluorescence study of neurotransmitter amino acid–5,6-benzocoumarin conjugates

Phototriggered release of tetrapeptide AAPV from coumarinyl and pyrenyl cages

Ala-Ala-Pro-Val (AAPV) is a bioactive tetrapeptide that inhibits human neutrophil elastase, an enzyme involved in skin chronic inflammatory diseases like psoriasis. Caged derivatives of this peptide were prepared by proper N- and C-terminal derivatisation through a carbamate or ester linkage, respectively, with two photoactive moieties, namely 7-methoxycoumarin-2-ylmethyl and pyren-2-ylmethyl groups. These groups were chosen to assess the influence of the photosensitive group and the type of linkage in the controlled photo release of the active molecule. The caged peptides were irradiated at selected wavelengths of irradiation (254, 300, and 350 nm), and the photolytic process was monitored by HPLC-UV. The results established the applicability of the tested photoactive groups for the release of AAPV, especially for the derivative bearing the carbamate-linked pyrenylmethyl group, which displayed the shortest irradiation times for the release at the various wavelengths of irradiation (ca. 4 min at 254 nm, 8 min at 300 nm and 46 min at 350 nm).

Light triggering of 5-aminolevulinic acid from fused coumarin ester cages

Light-triggered release of 5-aminolevulinic acid from various fused coumarin ester cages under UV/vis irradiation in MeOH/HEPES buffer (80 : 20).

Aminobenzocoumarinylmethyl esters as photoactive precursors for the release of butyric acid

The photorelease of butyric acid from new aminobenzocoumarin ester cages under UV/visible irradiation.