title: Phosphoramidites of base-modified 2'-deoxyinosine isosteres and solid-phase synthesis of d(GCI*CGC) oligomers containing an ambiguous base.
abstract: Novel phosphoramidites (1,2) of appropriately protected 2'-deoxyinosine isosteres (I*) such as allopurinol 2'-deoxyribofuranoside (4a) and 7-deaza-2'-deoxyinosine (4b) have been synthesized. They were employed together with the phosphoramidite of 2'-deoxyinosine in solid-phase synthesis of d(GCI*CGC) hexamers (12a-d). From thermodynamic data of these alternating hexamers it was shown that allopurinol 2'-deoxyribofuranoside destabilizes such duplexes less strongly than 2'-deoxyinosine. Additionally, the phosphoramidite of 7-deaza-2'-deoxyinosine (2) exhibits an extraordinary stability of the N-glycosylic bond. Since the new phosphoramidites are structurally related to 2'-deoxyinosine, they can be used in the construction of hybridization probes containing an ambiguous base.
mesh_terms: D000577:Amides; D001483:Base Sequence; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D006860:Hydrogen Bonding; D007288:Inosine / Q000031:analogs & derivatives; D009682:Magnetic Resonance Spectroscopy; D009838:Oligodeoxyribonucleotides / Q000032:analysis / Q000138:chemical synthesis*; D010756:Phosphoric Acids; D013816:Thermodynamics
chemical_list: D000577:Amides; D009838:Oligodeoxyribonucleotides; D010756:Phosphoric Acids; D007288:Inosine; C011067:phosphoramidic acid