Search results for "phenylenediamine"
showing 2 items of 22 documents
Interaction of mushroom tyrosinase with aromatic amines, o-diamines and o-aminophenols
2004
3-Amino-L-tyrosine was found to be a substrate of mushroom tyrosinase, contrary to what had previously been reported in the literature. A series of amino derivatives of benzoic acid were tested as substrates and inhibitors of the enzyme. 3-Amino-4-hydroxybenzoic acid, 4-amino-3-hydroxybenzoic acid and 3,4-diaminobenzoic acid were oxidized by this enzyme, as previously reported for Neurospora crassa tyrosinase, but 4-aminobenzoic acid and 3-aminobenzoic acid were not. Interestingly, 3-amino-4-hydroxybenzoic acid was oxidized five times faster than 4-amino-3-hydroxybenzoic acid, confirming the importance of proton transfer from the hydroxyl group at C-4 position. All compounds inhibited the m…
A Theoretical and Experimental Investigation of the Spectroscopic Properties of a DNA-Intercalator Salphen-Type ZnIIComplex
2014
The photophysical and DNA-binding properties of the cationic zinc(II) complex of 5-triethylammonium methyl salicylidene ortho-phenylenediiminato (ZnL 2 + ) were investi- gated by a combination of experimental and theoretical methods. DFT calculations were performed on both the ground and the first excited states of ZnL 2 + and on its possi- ble mono- and dioxidation products, both in vacuo and in selected solvents mimicked by the polarizable continuum model. Comparison of the calculated absorption and fluores- cence transitions with the corresponding experimental data led to the conclusion that visible light induces a two-elec- tron photooxidation process located on the phenylenediimi- nato…