A greener enantioselective synthesis of the antiviral agent North-methanocarbathymidine (N-MCT) from 2-deoxy-d-ribose

An enantioselective synthesis of suitably protected (1R,2S,4S,5S)-4-amino-1-(hydroxymethyl)bicyclo[3.1.0]hexan-2-ol, a key starting material for the synthesis of conformationally locked carbocyclic nucleosides, including the antiviral active North-methanocarbathymidine, is reported. Starting from 2-deoxyribose the target Boc-protected amine was prepared in 33% overall yield under conditions that are ecologically friendlier than previous methods.