Abstract
Covalently linked pyrrole (Py)- and imidazole (Im)-containing H-pin polyamides bind in the minor groove of specific DNA sequences with high affinity. The synthesis of 1,2,3-triazole-linked and heterodimeric H-pin polyamides 13a,b formed from the Huisgen reaction of an alkyne-containing f-PyPyPy (6) with an azide-containing f-ImPyIm (7) is reported. The reaction proceeded smoothly under thermal conditions to give an inseparable mixture of 1,4- and 1,5-isomers (13a and 13b, respectively) by column chromatography. When the reaction was conducted under ‘click’ or Cu(I)-catalyzed conditions or in the presence of the cognate DNA sequence, no desired product was observed. Preliminary results from DNA thermal denaturation and circular dichroism titration studies provided evidence of mixture 13a,b binding to the target DNA sequence 5′-TCTCAA-3′.
摘要
共价连接的吡咯(Py)和咪唑(Im)含量的H-pin聚酰胺与特定的DNA序列结合,具有高亲和力。报道了1,2,3-三唑连接和异二聚体H-pin聚酰胺13a、b的合成,其由含炔基的f-PyPyPy (6)与含叠氮基的f-ImPyIm (7)的Huisgen反应形成。反应在热条件下顺利进行,通过柱层析得到不可分离的1,4-和1,5-异构体混合物(分别为13a和13b)。当反应在“click”或Cu(I)催化条件下或在相应的DNA序列存在下进行时,未观察到所需的产物。DNA热变性和圆二色性滴定研究的初步结果表明,混合物13a、b与目标DNA序列5'-TCTCAA-3'结合。