Two Convergent Approaches toward Novel Carbocyclic C-Nucleosides

Abstract

Two convergent methodologies for construction of novel carbocyclic C-nucleosides allowing the syntheses of derivatives with uracil heterobase substituted at the position C-5 as well as C-6 were developed. The crucial step of the first methodology was the reaction of (6-chloro-2,4-dimethoxypyrimidin-5-yl)lithium, the nucleobase precursor, with suitable ketones, the carbocyclic pseudosugar precursors. The second approach was based on the copper-catalyzed cross-coupling between magnesiated pyrimidine and appropriate allyl chlorides. These methodologies were applied for the synthesis of novel carbocyclic C-nucleosides bearing cyclohexene or cyclohexane as a pseudosugar.