Syntheses of a radiolabelled CXCR2 antagonist AZD5069 and its major human metabolite

The CXCR2 antagonist AZD5069 has been synthesized in tritium and carbon-14-labelled forms. [(3) H]AZD5069 was prepared via reductive dehalogenation of an iodinated precursor with tritium gas to provide material with a specific activity of 25.1 Ci/mmol. [(14) C]AZD5069 was labelled in the pyrimidine ring from [(14) C]thiourea in an overall radiochemical yield of 18%. In addition, a synthetic route to the major metabolite of AZD5069 was developed. The synthesis of this metabolite was achieved from AZD5069 using a chemoselective Lindgren-Pinnick reaction in order to minimize oxidation of the sulphide group.