7-Nitroindol nucleoside

Among other approaches (Chaps. 10 and 12), the 2-dRL lesion maybe specifically generated by photolyzing the 7-nitroindol nucleoside (Kotera et al. 2000) [reactions (68)—(70)]. 

Kotera M, Roupioz Y, Defrancq E, Bourdat A-G, Coulombeau C, Lhomme J (2000) The 7-nitroindole nucleoside as a photochemical precursor of 2 -deoxyribonolactone access to DNA fragments containing this oxidative abasic lesion. Chem Eur J 6 4163-4169 Kremer ML (1999) Mechanism of the Fenton reaction. Evidence for a new intermediate. PhysChem Chem Phys 1 3595-3605... 

Photolysis of l-(2 -deoxyribosyl)-7-nitroindole was presumed to give the diradical 288, and hence, by radical recombination and fragmentation, the observed photoproducts 2-deoxyribonolactone and 7-nitrosoindole. When the 7-nitroindole nucleoside was incorporated into oligodeoxynucleotides, protolysis led to the formation of abasic positions. ... 

Nitroindole and 3-nitropyrrole have been assessed as universal bases in primers for dideoxy sequencing. The 5-nitroindole nucleoside was found to be superior. The melting temperatures of oligonucleotides containing acyclic universal base derivatives (176a) and (176b) was found to exceed those of the... 

The 5-nitroindole (121), benzimidazole and 5-nitro- and 6-nitro-ben-zimidazole as their 5 -triphosphates are all incorporated opposite each of the natural nucleotides by DNA Pol a and Klenow fragment with efficiencies up to 4000-fold better than a natural mismatch.Pol a preferentially incorporated each opposite pyrimidines, whilst Klenow preferentially incorporated them opposite purines. Both polymerases incorporated the triphosphates opposite an abasic site up to 140-fold more efficiently than dATP, whilst T4 DNA polymerase incorporated (121) 1000-fold more efficiently than dATP. Incorporation of the 5 -triphosphate derivative of the related indole nucleoside opposite... 

JV-6-etheno deoxy and ribo adenosine (112) and 3,A -4-etheno deoxy and ribo cytidine (113), 2-thiothymidine and 2-thiodeoxyuridine (114), nucleoside analogues with long alkyl chains instead of the base, e.g. (115), and 3-nitropyrrole (116) and 4-, 5-, or 6-nitroindole... 

---