Efficient regioselective synthesis of nucleoside conjugates was achieved by cycloaddition reaction of azides and alkynes using sodium ascorbate/CuSO₄ system as a catalyst. These 16 novel thymidine analogues were obtained in excellent yields (75–100%), employing mild reaction conditions with a broad scope of structural modification. For the compounds tested, no specific antiviral effects could be witnessed against a broad range of viruses.