Synthesis of N-1-Skatyl Uracil Derivatives

N-1 skatyl derivatives were obtained in moderate yields via the reaction of uracil, 5-fluorouracyl, and cytosine with gramine N-oxide or its methyl iodide. Gramine N-oxide was converted into gramine in good yield upon microwave irradiation in DMF solution. Gramine was also formed in DMF solution in the presence of DBU from gramine methyl iodide although microwave irradiation did not affect the yield of gramine. Gramine did not form from its methyl iodide upon microwave irradiation without DBU.