Metal Ion Chelates as Surrogates of Nucleobases for the Recognition of Nucleic Acid Sequences: The Pd2+ Complex of 2,6-Bis(3,5-dimethylpyrazol-1-yl)purine Riboside

摘要: A 2,6-bis(3,5-dimethylpyrazol-1-yl)purine ribonucleoside has been prepared and incorporated as a conventionally protected phosphoramidite into 9-mer 2'-O-methyl oligoribonucleotide. According to 1H NMR spectroscopic studies, this nucleoside forms with Pd(2+) uridine ternary complex that is stable at micromolar concentration range. CD studies on oligonucleotide hybridization, in turn, suggest the chelate of artificial nucleoside, when 2'-O-methyl-RNA oligomer, able recognize thymine within an otherwise complementary DNA strand. The duplex containing thymidine opposite turned out be somewhat more resistant heating than its counterpart 2'-deoxycytidine place thymidine, but only presence Pd(2+). UV-melting measurements, replacement 2'-O-methyladenosine markedly enhances hybridization target, irrespective identity base With T(m) value 2-4°C higher targets any other dependence much less clear case studies.