SYNTHESIS OF [C-14] KT3-671, 2-PROPYL-8-OXO-1-[(2'-(1H-[C-14] TETRAZOLE-5-YL) BIPHENYL-4-YL) METHYL]-4,5,6,7-TETRAHYDRO-CYCLOHEPTIMIDAZOLE,A NOVEL POTENT NONPEPTIDE ANGIOTENSIN-II RECEPTOR ANTAGONIST

1-[(2'-(1H-tetrazole-5-yl)biphenyl-4-yl)merhyl]-4, 5, 6, 7-tetrahydroc yclohept imidazole (KT3-671), which has been found to be a potent and selective angiotesin II receptor antagonist, was synthesized in C-14-l abelled form by using potassium[C-14]-cyanide. [C-14](KT3-671) 9 with a specific activity of 1.74GBq/mmol was prepared in four steps in 29.8 % overall radiochemical yield from potassium[C-14]-cyanide.