1818-71-9Relevant articles and documents
Nucleosides and nucleotides. XIII. Synthesis of thiopurine nucleosides from adenosine and guanosine derivatives by the sulfhydrolysis
Miura,Ueda
, p. 2064 - 2069 (1975)
-
-
Cramer,Schlingloff
, p. 3201,3203 (1964)
-
Novel isoguanine derivative of unlocked nucleic acid—Investigations of thermodynamics and biological potential of modified thrombin binding aptamer
Kotkowiak, Weronika,Czapik, Tomasz,Pasternak, Anna
, (2018/05/30)
Thrombin binding aptamer (TBA), is a short DNA 15-mer that forms G-quadruplex structure and possesses anticoagulant properties. Some chemical modifications, including unlocked nucleic acids (UNA), 20-deoxy-isoguanosine and 20-deoxy-4-thiouridine were previously found to enhance the biological activity of TBA. In this paper, we present thermodynamic and biological characteristics of TBA variants that have been modified with novel isoguanine derivative of UNA as well as isoguanosine. Additionally, UNA-4-thiouracil and 4-thiouridine were also introduced simultaneously with isoguanine derivatives. Thermodynamic analysis indicates that the presence of isoguanosine in UNA or RNA series significantly decreases the stability of G-quadruplex structure. The highest destabilization is observed for substitution at one of the G-tetrad position. Addition of 4-thiouridine in UNA or RNA series usually decreases the unfavorable energetic cost of the presence of UNA or RNA isoguanine. Circular dichroism and thermal denaturation spectra in connection with thrombin time assay indicate that the introduction of UNA-isoguanine or isoguanosine into TBA negatively affects G-quadruplex folding and TBA anticoagulant properties. These findings demonstrate that the highly-ordered structure of TBA is essential for inhibition of thrombin activity.
Synthesis of 2'-deoxyisoguanosine 5'-triphosphate and 2'-deoxy-5 methylisocytidine 5'-triphosphate
Jurczyk, Simona C.,Kodra, Janos T.,Park, Jeong-Ho,Benner, Steven A.,Battersby, Thomas R.
, p. 1005 - 1015 (2007/10/03)
The syntheses of the 5'-triphosphates of 2'-deoxyisoguanosine (= p3isoC(d)) and 2'-deoxy-5-methylisocytidine (= p3me5isoC(d)), two new bases for the genetic alphabet, are described. The triphosphates were synthesized from the corresponding nucleosides using a transient-protection procedure. The introduction of a methyl group at the 5-position of 2'- deoxyisocytidine remarkably improved the stability of the triphosphate. Characterization of the triphosphates included enzymatic incorporation opposite the complementary base in a template oligonucleotide.