O-Des[2-aminoethyl]-O-carboxymethyldehydroamlodipine is a major metabolite of the calcium channel inhibitor amlodipine .1 1.Taguchi, R., Naito, T., Sato, H., et al.Validated LC-MS/MS method for the simultaneous determination of amlodipine and its major metabolites in human plasma of hypertensive patientsTher. Drug Monit.39(6)625-631(2017)