2-Acetyl-1,3-cyclopentanedione-oxovanadium(IV) complexes. Acidity and implications for gastrointestinal absorption.
Since vanadyl sulphate has demonstrated insulin-like effects on glucose metabolism in animal and human trials, and organic vanadium complexes are better absorbed by the intestinal tract than vanadyl species, in this work the complexation of oxovanadium(IV) with 2-acetyl-1,3-cyclopentanedione is studied. Kinetic and equilibria in aqueous 1:1 chelation are investigated spectrophotometrically in aqueous solution at 25 degrees C. The mechanism proposed to account for the kinetic data involves a reversible pathway where VO(+2) reacts with the enolate ion of the ligand. From calculated kinetic and thermodynamic parameters, it can be expected that the rates between final and initial monocharged complex concentration could help a better control of the absorption through the lipophilic membranes in the intestinal tract.
Rojas
Antonio
A
Dpto. Ingeniería Agrícola y Forestal (Area de Tecnología de los Alimentos), E.T.S. Ingeníaras Agrarias, Universidad de Valladolid, 34004 Palencia, Spain.
Blanco
Carlos A
CA
Ronda
Felicidad
F
Gomez
Manuel
M
Caballero
Pedro A
PA
D000818:Animals; D002614:Chelating Agents; D003517:Cyclopentanes / Q000737:chemistry* / Q000493:pharmacokinetics; D004578:Electron Spin Resonance Spectroscopy; D006863:Hydrogen-Ion Concentration; D007408:Intestinal Absorption / Q000187:drug effects*; D007700:Kinetics; D013329:Structure-Activity Relationship; D014638:Vanadates / Q000737:chemistry / Q000493:pharmacokinetics*; D017968:Vanadium Compounds / Q000737:chemistry / Q000493:pharmacokinetics
D002614:Chelating Agents; D003517:Cyclopentanes; D017968:Vanadium Compounds; C075743:oxovanadium IV; D014638:Vanadates; C034028:vanadyl sulfate