Exact Assignment of 13C NMR of Pyrrole-Imidazole Polyamides using HMBC (2)

Abstract

Netropsin and distamycin possess DNA binding properties toward AT-rich regions. Both compounds are constructed by 1-methylpyrrole amide (Py) units and adopt crescent-shaped conformations strictly complementary to the minor groove of the DNA helix. We have already reported about exact 13C NMR assignments of some Py-polyamides using HMBC techniques. It is well known that 1-methylimidazole amide (Im) possesses a DNA binding property toward G. Combination of 1-methylpyrrole amide and 1-methylimidazole amide led to Py-Im polyamide concept which binds to any kind of sequences of double strand DNA. However, as far as we surveyed, exact 13C NMR assignments of 1-methylimidazole amide compounds have not been reported. Therefore we synthesized some 1-methylimidazole amide containing compounds and assigned 13C NMR peaks exactly by mainly using HMQC and HMBC technique