3- anilidates to protect phosphate groups

Nucleotides in aqueous solution can be alkylated at the phosphate (and in some cases the nucleoside also) by the action of l-oxidopyridin-2-yldiazo-methane (33). - The protecting group may be removed from the phosphate with snake venom phosphodiesterase, or generally by acetic anhydride treatment, followed by ammonia. Phosphoramidates have been described previously as phosphate-protecting groups, and if 2-naphthylamine is used as its anilidate for this purpose, organic solvent extraction (as above) is possible. A variation on this theme is to use dianilidophosphochloridate (34) as a... 

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