The First Postsynthetic 5′-5′ Intercalators in Triplex DNA - Solid-Phase Postsynthetic<i>Sonogashira</i>Reaction and Homocouplings on Arylacetylenes
作者:Niels Bomholt、Vyacheslav V. Filichev、Erik B. Pedersen
DOI:10.1002/hlca.200800397
日期:2009.4
Abstractmagnified imageWe report herein a new technique for postsynthetic modifications of on‐column oligonucleotides. CPG‐Supported nonamer polypyrimidine oligodeoxynucleotides comprising 2‐(3‐iodobenzyloxy)ethyl phosphate at the terminal 5′‐ends were successfully capped with 1,3‐diethynylbenzene under Sonogashira reaction conditions, resulting in novel intercalating 5′‐5′ linker in alternate strand Hoogsteen triplex‐forming oligonucleotidej (TFO) X. In addition, novel 5′‐5′‐linked alternate strand TFOs, Y and Z, were isolated as a result of on‐column Sonogashira coupling with 1,3‐diethynylbenzene, followed by Cu‐catalyzed oxidative arylacetylenic homocoupling(s) between neighboring terminal arylacetylenes. Linkers X, Y, and Z represent the first postsynthesis 5′‐5′ intercalating linkers for alternate strand TFOs. Reproducibility and verification by independent syntheses using conventional phosphoramidite chemistry and DNA synthesis, as well as thermal stability and molecular modelling studies are included.