Optosensing properties of fac-Re(CO)(3)(dpknph)Cl (dpknph=di-2-pyridyl ketone p-nitrophenyl hydrazone) toward chemotactic N-formylamino acids

Optical measurements on fac-Re(CO)(3)(dpknph)Cl in polar non-aqueous solvents in the presence and absence of NaBH(4)/KPF(6) revealed reversible interconversion between the high (beta-) and low (alpha-) energy electronic states of fac-Re(CO)(3)(dpknph)Cl. The reversibility of these interactions and the disturbance of the equilibrium distribution of the low (alpha-) and high (beta-) energy electronic state upon addition of NaBH(4)/KPF(6) mark improvement in the optosensing properties of fac-Re(CO)(3)(dpknph)Cl. The optical behavior of fac-Re(CO)(3)(dpknph)Cl in the presence and absence of the l-methionine and chemotactic N-formylamino acids: N-formyl-l-methionine (NFM), N-formyl-l-glycine (NFG) and N-formyl-l-phenylalanine (NFP) shows the alpha- and beta-electronic states of fac-Re(CO)(3)(dpknph)Cl to be insensitive to l-methinonine and highly sensitive to N-formylamino acids. N-formylamino acids in concentrations NFG>NFP.