Biomaterial Database

Kinetic studies on anthralin photooxidation. 1990

K Müller, and R C Kanner, and C S Foote

Department of Chemistry and Biochemistry, University of California, Los Angeles 90024.

The photooxidation of the antipsoriatic drug anthralin (1,8-dihydroxy-9-anthrone) has been studied by several kinetic techniques, including direct observation of 1O2 (1 delta g) luminescence at 1.27 microns. The rate of deactivation of 1O2 increases at higher pH, demonstrating that the trihydroxyanthracene anion is the reactive species. Direct determination of the rate constant of 1O2 deactivation (kR + kQ) in deuterated buffer systems by luminescence quenching gave a value of 3.0 x 10(8) M-1 s-1 for the anion; the neutral anthrone is unreactive. The rate constant for the neutral anthrone in benzene-d6 is 2.8 x 10(4) M-1 s-1. Competition experiments with tetramethylethylene in acetonitrile gave a rate constant for reaction alone (kR) of 2.1 x 10(8) M-1 s-1 for the anion.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D010777	Photochemistry	A branch of physical chemistry which studies chemical reactions, isomerization and physical behavior that may occur under the influence of visible and/or ultraviolet light.	Photochemistries
D000875	Anthralin	An anthracene derivative that disrupts function and structure of MITOCHONDRIA and is used for the treatment of DERMATOSES, especially PSORIASIS. It may cause FOLLICULITIS.	1,8-Dihydroxy-9-anthrone,Dithranol,1,8,9-Anthracenetriol,1,8-Dihydroxy-9(10H)-anthracenone,Anthraforte,Anthranol,Cignolin,Cygnoline,Dihydroxyanthranol,Dithrocream,Ditranol FNA,Lasan,Micanol,Psoradrate,Psoricrème,1,8 Dihydroxy 9 anthrone,FNA, Ditranol
D049449	Luminescence	Emission of LIGHT when ELECTRONS return to the electronic ground state from an excited state and lose the energy as PHOTONS. It is sometimes called cool light in contrast to INCANDESCENCE. LUMINESCENT MEASUREMENTS take advantage of this type of light emitted from LUMINESCENT AGENTS.	Luminescence, Physical,Chemiluminescence,Chemiluminescence, Physical,Physical Chemiluminescence,Physical Luminescence