Synthesis and Characterization of 2-Iodo-4-[5′-(4'″-Methylpiperazin-1'″-yl)-2′,5′-bi-1h-Benzimidazol-2 ′-Yl]Phenol (iodoHoechst 33258) and 2,5-Disubstituted Benzimidazole Model Compounds

Abstract

The product of iodination of the DNA-binding dye Hoechst 33258,4-[5′- (4′′′-methylpiperazin-1′′′-yl)-2′,5′-bi-1H-benzimidazol-2′-yl]phenol (1), has been identified as the monoiodo derivative, i.e. 2-iodo-4-[5′- (4′′′-methylpiperazin-1′′′-yl)-2′,5′-bi-1H-benzimidazol-2′-yl]phenol (2), by mass spectrometry and by comparison of the ¹H and ¹³C n.m.r . spectra of (1) and (2) with those of 2,5-disubstituted benzimidazole model compounds (3) and (4).