355390-06-6Relevant articles and documents
Site-specific insertion of the (5R*) and (5S*) diastereoisomers of 1-[2-deoxy- β-D-erythro-pentofuranosyl]-5-hydroxyhydantoin into oligodeoxyribonucleotides
Muller,Gasparutto,Lebrun,Cadet
, p. 2091 - 2099 (2007/10/03)
The insertion of the (5R*) and (5S*) diastereoisomers of 1-[2-deoxy-β-D-erythro-pentofuranosyl]-5-hydroxyhydantoin (1) a major oxidation product of 2′-deoxycytidine upon exposure to OH radicals, excited photosensitizers, or ozone - into oligonucleotides is reported. It was achieved by means of phosphoramidite chemistry, using the solid-phase synthesis approach. The synthesis of the phosphoramidite synthon 7 required 6 steps from 3′-O-(tert-butyldimethylsilyl)-2′-deoxycytidine and involved protection of the secondary hydroxy group (5-OH) of the modified base by the nonstandard levulinyl group. The modified phosphoramidite synthon 7 was efficiently incorporated into several oligonucleotides (3-mer, 14-mer, 22-mer) by solid-support assembling. The presence and the integrity of the (5R*) and (5S*) diastereoisomers of 1-[2-deoxy-β-D-erythro-pentofuranosyl]-5-hydroxyhydantoin in the synthetic oligomers was confirmed by electrospray ionization mass spectrometry, together with HPLC and MALDITOF mass-spectrometric analyses of enzymatic digestions. The use of exonucleases (calf spleen phosphodiesterase and bovine intestinal mucosa phosphodiesterase) clearly showed that enzymatic hydrolysis of the phosphodiester bonds between the (5R*) and (5S*) diastereoisomers of 1-[2-deoxy-β-D-erythro-pentofuranosyl]-5-hydroxyhydantoin and normal 2′-deoxyribonucleosides is prevented, while endonuclease (nuclease P1) is able to cleave the lesion residue from the oligonucleotides.
