Diazo Coupling of Catecholamines with Poly(organophosphazenes)

Polymer-bound catecholamines have been prepared by the diazotization of high-polymeric [NP(OC6H5)z(OC6H4NH2-p)),]n, followed by coupling to dopamine, dl-epinephrine, and dl-norepinephrine. These reactions were preceded by model compound studies with the cyclic trimer N3P3(OC6H5)5OC6H4NH2. In both cases, the aminophenoxy units were generated by reduction of 4-nitrophenoxy groups with Pt02 and hydrogen. The phosphazene skeleton was unaffected by the reduction, diazotization, and diazo coupling processes. The physical characteristics of the trimers and high polymers are described. The polymeric azocatecholamine derivatives were purified by gel permeation chromatography, which reduced contamination by the unbound catecholamine to undetectable levels. The polymeric derivatives were found to elicit inhibition of prolactin release from rat pituitary cells in culture for 48 h.