O6-Phenyl-deoxyinosine (O6-Ph-dI) is classified as a convertible dA nucleotide. After incorporation into an oligo, reaction of the O6-phenyl on the inosine base with a primary amine displaces the oxygen atom, and converts the nucleotide into a N6-substituted dA. Oligos containing O6-Ph-dI modifications are useful precursors in studies requiring a base-modified dA in which the modification is a specific moiety. For example, O6-Ph-dI modified oligos have been reacted with 1,4-diaminobutane(1) in order to subsequently form a DNA molecule with active amines at the N6 position of several A positions in the oligo, for use as part of an affinity purification matrix. Oligos containing O6-Phenyl-dI modifications are also useful precursors in studies requiring cross-linking, at A position(s), between oligos, or between an oligo and an enzyme (2)
1. Larson, C.J.; Verdine, G.L. A High-Capacity Column for Affinity Purification of Sequence-Specific DNA Binding Proteins. Nucleic Acids Res. (1992), 30: 3525.
2. Corn, J.E.; Berger, J.M. FASTDXL. Structure (2007), 15: 773-780.