Oligonucleotides containing 7-vinyl-7-deazaguanine as a facile strategy for expanding the functional diversity of DNA

A modified nucleobase 7-vinyl-7-deazaguanine (VG) produced adducts with maleimides through Diels–Alder cycloaddition under very mild conditions. By this method, post-synthetic modification to oligonucleotides with diverse functionality (carboxylic acid, pyrene, benzophenone, succinimidyl ester, nitroxide and biotin) was accomplished.