Tan T H Samuel, Worthington Roberta J, Pritchard Robin G, Morral Jordi, Micklefield Jason
School of Chemistry and Manchester Interdisciplinary Biocentre, The University of Manchester, 131 Princess Street, Manchester, UKM1 7DN.
Org Biomol Chem. 2007 Jan 21;5(2):239-48. doi: 10.1039/b613384n. Epub 2006 Dec 1.
By chemically modifying or replacing the backbone of oligonucleotides it is possible to modulate the DNA and RNA recognition properties and fine-tune the physiochemical properties of oligomers. This is important because it challenges our understanding of natural nucleic acid structural and recognition properties and can lead to nucleic acid mimics with a wide range of applications in nucleic acid targeting, analysis or diagnostics. In this paper we describe the solid phase synthesis of pyrrolidine-amide oligonucleotide mimics (POMs) using Fmoc-peptide chemistry. This required the synthesis of adeninyl, cytosinyl, thyminyl and guaninyl pyrrolidine monomers, with Fmoc- and standard acyl-protecting groups on the exocyclic amino groups and nucleobases respectively. These monomers were used to synthesise several thyminyl and adeninyl POM pentamers, with modest coupling efficiency. The pentamers were purified by RP-HPLC, characterised by mass spectrometry and their DNA and RNA binding properties were investigated using UV thermal denaturation/renaturation experiments. This revealed that all the pentamers exhibit strong affinity for complementary nucleic acids. The further evaluation of longer mixed-sequence POMs is described in a second accompanying paper (R. J. Worthington et al., Org. Biomol. Chem., 2006, DOI: 10.1039/b613386j).
通过对寡核苷酸的主链进行化学修饰或替换，可以调节DNA和RNA的识别特性，并微调寡聚物的物理化学性质。这很重要，因为它挑战了我们对天然核酸结构和识别特性的理解，并可能导致在核酸靶向、分析或诊断中有广泛应用的核酸模拟物。在本文中，我们描述了使用Fmoc-肽化学方法固相合成吡咯烷酰胺寡核苷酸模拟物（POMs）。这需要合成腺嘌呤基、胞嘧啶基、胸腺嘧啶基和鸟嘌呤基吡咯烷单体，分别在外环氨基和核碱基上带有Fmoc和标准酰基保护基团。这些单体用于合成几种胸腺嘧啶基和腺嘌呤基POM五聚体，偶联效率适中。通过反相高效液相色谱（RP-HPLC）对五聚体进行纯化，用质谱进行表征，并使用紫外热变性/复性实验研究它们与DNA和RNA的结合特性。结果表明，所有五聚体对互补核酸都表现出很强的亲和力。另一篇配套论文（R. J. Worthington等人，《有机生物分子化学》，2006年，DOI: 10.1039/b613386j）描述了对更长的混合序列POMs的进一步评估。
