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), Vol. 137:1
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
COPPER COMPLEXES
BIOCHEMICAL REACTION KINETICS
PLANT GROWTH REGULATORS
EXPERIMENTAL DATA
PH VALUE
POLAROGRAPHY
PURINES
SPECTROPHOTOMETRY
SUPEROXIDE DISMUTASE
SUPEROXIDE RADICALS
TITRATION
AROMATICS
AZAARENES
COMPLEXES
DATA
ENZYMES
HETEROCYCLIC COMPOUNDS
INFORMATION
KINETICS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDOREDUCTASES
RADICALS
REACTION KINETICS
TRANSITION ELEMENT COMPLEXES
560303* - Chemicals Metabolism & Toxicology- Plants- (-1987)