Ribofuranosylation of a variety of alcohols with ribofuranosyl iodides in the presence of a base and triphenylphosphine oxide afforded the corresponding α-ribofuranosides with diastereoselectivities ≥ 99:1. This reaction can be carried out under mildly basic conditions and is thus compatible with acid-sensitive functional groups.

Inosine derivatives bearing a phosphodiester group at the O6-position of the nucleobase were synthesized via phosphitylation of the carbonyl oxygen using phosphoramidites activated by non-nucleophilic acidic activators.

We developed a method to convert a nucleoside 5′-H-boranophosphonate monoester into the corresponding nucleoside 5′-boranophosphorothioate monoester through temporary protection of the H-boranophosphonate monoester moiety as a diester with 9-fluorenylmethanol, subsequent sulfurization of the P–H group and removal of the 9-fluorenylmethyl group. Although the isolation of the resultant boranophosphorothioate monoester was found to be difficult due to instability of the compound, this new method proved to be useful to synthesize some conjugates of the nucleoside 5′-boranophosphorothioate with other biomolecules, such as cholesterol and an amino acid.

Inosine derivatives bearing a phosphodiester group at the O6-position of the nucleobase were synthesized via phosphitylation of the carbonyl oxygen using phosphoramidites activated by non-nucleophilic acidic activators.