Polymer support synthesis of oligodeoxyribonucleotide with an aminoethyl or aminohexyl group at the 5' end by the phosphite-triester approach.

Abstract

An N-monomethoxytrityloxyethyl or-hexyl group was introduced onto the 5'-phosphoryl group of N-protected-3'-benzoyldeoxynucleosides. After 3'-O-debenzoylation and phosphitylation, they were converted 3'-phosphoramidite derivatives. These were used at the last coupling reaction in the synthesis of octadecadeoxynucleotides with an aminoethyl or aminohexyl group at the 5' end by the phosphite-triester method on long-chain alkylamine controlled pore glass beads. Partially deblocked oligomers, after thiophenol and ammonia treatment, were separated rapidly on a reversed-phase C-18 silica gel column by utilizing the hydrophobic nature of the monomethoxy-trityl group. After AcOH treatment, the octadecamers with an aminoethyl or aminohyxyl group at the 5' end were obtained and then coupled with a fluorescent compound. The ultraviolet-temperature profiles were measured after hybridization with a complementary oligonucleotide.