Phosphodiester hydrolysis by metal ion macrocyclic dioxotetraamine complexes bearing alcohol pendant in comicellar solution

Abstract

Four new long chain alkyl substituted 2,6-dioxo-1,4,7,10-tetraazacyclododecanes bearing an alcohol pendant has been synthesized. They coordinate with metal ion (Zn 2+, Cu 2+, Ni 2+, Co 2+) to yield 1:1 five-coordinate complexes. The catalytic properties of these complexes have been investigated for the hydrolysis of bis( p-nitrophenyl) phosphate (BNPP) in comicellar solution. The alcohol pendant has a profound effect on the catalytic properties of macrocyclic complexes, and the nature of transition metal ion, micellar microenvironment, hydrolysis temperature, hydrophobic interactions between the metallocatalyst and substrate are also important factors in the hydrolysis of BNPP. Under the physiological conditions (pH=7.41, 35±0.1 °C), the complexes exhibit higher catalytic activity (up to over 2–3 orders of magnitude) than metal ion or ligand alone in the hydrolysis of BNPP in comicellar solution with 2 mM Brij 35.