Synthesis of deuterium-labelled 6-[5-(4-amidinophenyl)furan-2-yl]nicotinamidine and N-alkoxy-6-{5-[4-(N-alkoxyamidino)phenyl]-furan-2-yl}-nicotinamidines

6-[5-(4-Amidinophenyl)furan-2-yl]nicotinamidine-d(4) (5) was synthesized from 6-[5(4-cyanophenyl)furan-2-yl]nicotinonitrile-d(4) (3), through the bis-O-acetoxy-amidoxime followed by hydrogenation. Compound 3 was prepared from 6-(furan-2-yl)nicotinonitrile by a Heck coupling reaction with 4-bromobenzonitrile-d(4), a product of selective cyanation reaction of 1,4-dibromobenzene-d(4) with Cu(1)CN. Deuterium-labelled N-methoxy-6-{5-[4-(N-methoxy-amidinophenyl]-furan-2-yl}-nicotinamidines were prepared via methylation of their respective amidoximes with dimethyl sulfate-d(6) in aqueous sodium hydroxide in good yields. Copyright (C) 2004 John Wiley Sons, Ltd.