Deazapurine Derivatives. VIII: Synthesis of 7‐substituted 3‐β‐<i>D</i>‐ribofuranosylimidazo[4,5‐<i>b</i>]pyridines: 1‐deazaadenosine and related compounds

Abstract

Abstract Fusion of 7‐chloroimidazo[4,5‐ b ]pyridine (IV, 6‐chloro‐1‐deazapurine) with tetra‐ O ‐acetyl‐β‐ D ‐ribofuranose (V), gave predominantly the tri‐ O ‐acetyl derivative of 7‐chloro‐3‐β‐ D ‐ribofuranosylimidazo[4,5‐ b ]pyridine (β‐VI) and a small amount of the corresponding α‐anomer (α‐VI). After removal of the acetyl groups, the ribofuranosides β‐VII and α‐VII were obtained as crystalline compounds. It has been shown, that the sugar residue in both anomers is attached to position 3. The anomeric configuration has been assigned with the assistance of several independent methods. Starting from the β‐ribofuranoside β‐VII, l‐deazaadenosine (XII) and some related compounds were synthesized.