Synthesis of 2′-deoxy-2′-spirocyclopropyl cytidine as potential inhibitor of ribonucleotide diphosphate reductase

Based on the mechanism of action of ribonucleoside diphosphate reductase (RDPR), a new class of nucleosides that may act as inhibitors of this enzyme was designed. Starting from uridine, a 2′-deoxy-2′-spirocyclopropyl derivative of cytosine was prepared. The key step of the synthesis is the condensation of diazomethane with a suitably protected 2′-methylene nucleoside. Light-induced nitrogen extrusion affords the cyclopropane ring.