Synthesis of “Reversed” and “Double Headed” Nucleosides

Abstract The synthesis of several partially and fully deprotected “reversed” nucleosides are described starting from “reversed” 5-iodouracil-1-yl nucleoside 1. The preparation of a novel purine-purine and mixed purine-pyrimidine “double headed” nucleosides via “reversed” purine nucleoside 12 is also described.