Metal(II) Binding Ability of a Novel N-protected Amino Acid. A Solution-State Investigation on Binary and Ternary Complexes With 2,2'-bipyridine

J Inorg Biochem. 2000 Mar;78(4):355-61. doi: 10.1016/s0162-0134(00)00064-7.

Abstract

The binary and ternary systems 2,2'-bipyridine (bpy)-M(II)-NO2psglyH2 (M(II) = Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Pb(II); NO2psglyH2 = N-(2-nitrophenylsulfonyl)glycine) were investigated in aqueous solution by means of potentiometry and electron spectroscopy in order to identify the type, number and stability of the complex species as a function of pH and metal-to-ligand molar ratio. The aim is to evaluate the effect of a substituent on the phenyl ring of the N-sulfonyl amino acids on their coordination properties. The prevailing species in the binary systems is the [ML] (M = Co(II), Ni(II), Cu(II), Cd(II), Pb(II)) where the amino acid molecule is in the dianionic form and coordinates the metal ion through both carboxylic oxygen and deprotonated sulfonamidic nitrogen, while in the Mn(II)- and Zn(II)-containing binary system the only complex species found are those with the amino acid in the monoanionic form. In the ternary 2,2'-bipyridine-containing systems the chelating coordination mode of the dianionic amino acid is maintained with M(II) = Co(II), Ni(II), Cu(II), Cd(II), Pb(II) and the addition of the aromatic base also enables the Zn(II) ion to substitute for the sulfonamide nitrogen-bound hydrogen of NO2psglyH2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2,2'-Dipyridyl / metabolism*
  • Cadmium / metabolism
  • Cobalt / metabolism
  • Copper / metabolism
  • Electrons
  • Hydrogen-Ion Concentration
  • Ions
  • Kinetics
  • Lead / metabolism
  • Manganese / metabolism
  • Metals / metabolism*
  • Nickel / metabolism
  • Potentiometry
  • Spectrum Analysis
  • Zinc / metabolism

Substances

  • Ions
  • Metals
  • Cadmium
  • Lead
  • Cobalt
  • Manganese
  • 2,2'-Dipyridyl
  • Copper
  • Nickel
  • Zinc