120595-71-3Relevant academic research and scientific papers
A convenient synthesis of 2'-deoxy-6-thioguanosine, ara-guanine, ara-6-thioguanine and certain related purine nucleosides by the stereospecific sodium salt glycosylation procedure [1]
Hanna,Ramasamy,Robins,Revankar
, p. 1899 - 1903 (1988)
A simple and high-yield synthesis of biologically significant 2'-deoxy-6-thioguanosine, ara-6-thioguanine and araG has been accomplished employing the stereospecific sodium salt glycosylation method. Glycosylation of the sodium salt of 6-chloro- and 2-amino-6-chloropurine (1 and 2, respectively) with 1-chloro-2-deoxy-3,5-di-O-(p-toluoyl)-α-D-erythro-pentofuranose gave the corresponding N-9 substituted nucleosides as major products with the β-anomeric configuration (4 and 5, respectively) along with a minor amount of the N-7 positional isomers (6 and 7). Treatment of 4 with hydrogen sulfide in methanol containing sodium methoxide gave 2'-deoxy-6-thioinosine in 93% yield. Similarly, 5 was transformed into 2'-deoxy-6-thioguanosine (β-TGdR, 11) in 71% yield. Reaction of the sodium salt of 2 with 1-chloro-2,3,5-tri-O-benzyl-α-D-arabinofuranose gave N-7 and N-9 glycosylated products 13 and 9, respectively. Debenzylation of 9 with boron trichloride at -78° gave the versatile intermediate 2-amino-6-chloro-9-β-D-arabinofuranosylpurine 62% yield. Direct treatment of 14 with sodium hydrosulfide furnished ara-6-thioguanine. Alkaline hydrolysis of 14 readily gave 9-β-D-arabinofuranosylguanine (araG, 17), which on subsequent phosphorylation with phosphorus oxychloride in trimethyl phosphate afforded araG 5'-monophosphate.
Synthesis and duplex stability of oligonucleotides containing adenine-guanine analogues
Brown,Lin
, p. 129 - 139 (2007/10/02)
The nucleosides N6-methoxy-2'-deoxyadenosine (dZ) and 2-amino-9-(2-deoxy-β-ribofuranosyl)-6-methoxyaminopurine (dK) have been synthesised and converted into 5'-O-dimethoxytrityl 3'-(2-cyanoethyl N,N-diisopropylphosphoramidites). These monomers have been used in machine DNA synthesis to give a set of heptadecanucleotides containing up to three analogue nucleotides. The melting transitions (T(m) show that the 17-mer duplexes containing Z·T and Z·C base-pairs have closely similar stabilities, as have those containing K·T and K·C pairs. They are less stable than the corresponding fully complementary duplexes, but more stable than those containing mismatched pairs. This, in the case of dZ, is in accord with the amino-imino tautomeric ratio of ~1:4 observed for the nucleoside in methyl sulfoxide. The application of oligomers containing such 'degenerate' bases in oligonucleotide probes and primers is discussed. The nucleosides N6-methoxy-2′-deoxyadenosine (dZ) and 2-amino-9-(2-deoxy-β-ribofuranosyl)-6-methoxyaminopurine (dK) have been synthesised and converted into 5′-O-dimethoxytrityl 3′-(2-cyanoethyl N,N-diisopropylphosphoramidites). These monomers have been used in machine DNA synthesis to give a set of heptadecanucleotides containing up to three analogue nucleotides. The melting transitions (Tm) show that the 17-mer duplexes containing Z·T and Z·C base-pairs have closely similar stabilities, as have those containing K·T and K·C pairs. They are less stable than the corresponding fully complementary duplexes, but more stable than those containing mismatched pairs. This, in the case of dZ, is in accord with the amino-imino tautomeric ratio of approximately 1:4 observed for the nucleoside in methyl sulfoxide. The application of oligomers containing such 'degenerate' bases in oligonucleotide probes and primers is discussed.
