The transposition of atoms or groups in the purine nucleobase of G/dG provides isomers that have altered base-pairing capabilities. We offer a family of guanosine isomers in nucleoside and phosphoramidite forms. Isoguanosines are important in the field of non-natural base pairing. In 1989, Benner and co-workers⁽¹⁾ reported the enzymatic incorporation of iso-G into RNA and DNA and characterized the distinct non-natural base pairing that resulted, especially pairing involving the similarly transposed isomer of dC known as iso-dC (we offer the closely-related compound 5-Methyliso-dC, PY7255).
Iso-G and Iso-dG are part of a family that includes Guanosine (PR3703), 2'-Deoxyguanosine (PR3452), the isomeric nucleosides, 2'-Deoxypseudoguanosine (Pseudo-dG, PRA10103), 2'-Deoxypseudoisoguanosine (Pseudoiso-dG, PRA10104), and the phosphoramidites Pseudo-dG-CE Phosphoramidite (BA0312) and Pseudoiso-dG-CE Phosphoramidite (BA 0314).

Ref:

1. Switzer, C. Y.; Moroney, S. E.; Benner, S. A. J. Am. Chem. Soc. 1989, 111, 8322-8323.