Heetebrij Robert J, de Kort Martin, Meeuwenoord Nico J, den Dulk Hans, van der Marel Gijs A, van Boom Jacques H, Reedijk Jan
Leiden Institute of Chemistry Gorlaeus Laboratories, Leiden University, P.O. Box 9502, The Netherlands.
Chemistry. 2003 Apr 14;9(8):1823-7. doi: 10.1002/chem.200390209.
Undesired N(7) platination of 2'-deoxyguanosine residues at predetermined sites in an oligodeoxynucleotide (ODN) sequence is prevented by applying the sterically demanding diphenylcarbamoyl (DPC) as an O(6)-protecting group. The presence of a base-labile oxalyl linker between the immobilized 3'-nucleotide and controlled pore glass (CPG) allows cleavage of the protected ODN from the support and leaves DPC protection unaffected. This method provides an ODN with specifically blocked guanine-N(7) sites for platination. In the hexanucleotides prepared in this study, 5'-GGBGGT-3'(for B=T, C and A), a platinum GG adduct is introduced at G4,G5. These site-specific platinated hexamers were isolated in a yield of 65 %, and were fully characterized by using reversed-phase HPLC (high performance liquid chromotography), LCMS (liquid chromatography-mass spectrometry), MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry), PAGE (polyacrylamide gel electrophoresis) and Maxam-Gilbert sequencing analysis.
通过应用空间位阻较大的二苯基甲酰基（DPC）作为O(6)-保护基团，可防止在寡脱氧核苷酸（ODN）序列的预定位点上出现不期望的2'-脱氧鸟苷残基的N(7)铂化。固定化的3'-核苷酸与可控孔径玻璃（CPG）之间存在碱不稳定的草酰连接子，这使得受保护的ODN能够从载体上裂解下来，而DPC保护不受影响。该方法提供了具有特定封闭鸟嘌呤-N(7)位点的ODN用于铂化。在本研究制备的六核苷酸5'-GGBGGT-3'（其中B = T、C和A）中，在G4、G5处引入了铂GG加合物。这些位点特异性铂化的六聚体以65%的产率分离得到，并通过反相高效液相色谱（HPLC）、液相色谱-质谱联用（LCMS）、基质辅助激光解吸/电离飞行时间质谱（MALDI-TOF MS）、聚丙烯酰胺凝胶电泳（PAGE）和Maxam-Gilbert测序分析进行了全面表征。
