NEW PHOSPHITYLATING REAGENT IN THE NUCLEOTIDE CHEMISTRY CONTAINING 2 4-NITROPHENOXY LEAVING GROUPS - REMARKABLY FAST AND CLEAN PHOSPHITYLATIONS ACTIVATED BY DBU LEADING TO THIO-OLIGONUCLEOTIDES AND SELENO-OLIGONUCLEOTIDES
J. Helinski et al., NEW PHOSPHITYLATING REAGENT IN THE NUCLEOTIDE CHEMISTRY CONTAINING 2 4-NITROPHENOXY LEAVING GROUPS - REMARKABLY FAST AND CLEAN PHOSPHITYLATIONS ACTIVATED BY DBU LEADING TO THIO-OLIGONUCLEOTIDES AND SELENO-OLIGONUCLEOTIDES, Tetrahedron letters, 34(40), 1993, pp. 6451-6454
A new synthetic approach to modified oligonucleotides based on N,N'-di
isopropyl-di- (4-nitrophenyl)phosphoroamidite 1 is described. The proc
edure involves displacement of either 4-nitrophenoxy or diisopropylami
no ligands. The former proceeds very fast in the presence of DBU, the
latter requires activation by tetrasole. This method allows rapid and
almost quantitative construction of modified nucleotides derived from
thio- and selenophosphorus acids.