Model reactions targeted at the synthesis of carbon-14 labeled CI-996, a potent antagonist of angiotensin II receptor (1)

Article abstract of DOI:10.1002/jlcr.2580340303

A reaction sequence suitable for the preparation of an analog of 2-propyl-1-[[2'-(1H-tetrazol-5-yl)[1,1'-biphenyl]-4-yl]methyl-4-[2-(tr ifluoroacetyl)-1H-pyrrol-1-yl]-1H-imidazole-5-carboxylic acid, with ¹⁴C at the methylene bridge was developed. The would-be labeled fragment (12) was derived from 4-iodobenzenemethanol (6) which itself was constructed from 1,4-dibromobenzene by the application of silicon chemistry. Pd(o) catalyzed coupling of TBDMS protected 6 and a tetrazole borate 10 gave the compound 12 which upon further transformation to the mesylate 13, N-alkylated an imidazole to furnish target compound.