Superoxide dismutase mimetic activity of cytokinin-copper(II) complexes
Dissociation constants of cytokinins, derivatives of purine which form complexes which cupric ion, were determined by spectrophotometry and the stability constants of their copper complexes by pH titration. The values found for kinetic were 3.76, 9.96, 7.8, and 15.3 for pK/sub 1/ for pK/sub 2/, logk/sub 1/, and log..beta../sub 2/, respectively, and those for 6-benzylaminopurine were, in the same order, 3.90, 9.84, 8.3, and 15.9. The copper(II) complexes with kinetin and 6-benzylaminopurine had superoxide dismutase mimetic activity, and the reaction rate constants with superoxide, which were determined by polarography. were 2.3 x 10/sup 7/ M/sup -1/s/sup -1/ for kinetin and 1.5 x 10/sup 7/ M/sup -1/s/sup -1/ for 6-benzylaminopurine at pH 9.8 and 25/sup 0/C.
- Research Organization:
- Univ. of Tokyo, Japan
- OSTI ID:
- 5071246
- Journal Information:
- Biochem. Biophys. Res. Commun.; (United States), Journal Name: Biochem. Biophys. Res. Commun.; (United States) Vol. 137:1; ISSN BBRCA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AROMATICS
AZAARENES
BIOCHEMICAL REACTION KINETICS
COMPLEXES
COPPER COMPLEXES
DATA
ENZYMES
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
INFORMATION
KINETICS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDOREDUCTASES
PH VALUE
PLANT GROWTH REGULATORS
POLAROGRAPHY
PURINES
RADICALS
REACTION KINETICS
SPECTROPHOTOMETRY
SUPEROXIDE DISMUTASE
SUPEROXIDE RADICALS
TITRATION
TRANSITION ELEMENT COMPLEXES