STEREOSELECTIVE SYNTHESIS OF N1-6-METHYLURIDINE AND RELATED 2-SUBSTITUTED ANALOGUES

摘要

Coupling reaction of 2-substituted-6-methyl-4(3H)-pyrimidinones(1a,b)with 1-O-acetyl-2,3,5-tri-O-benzoyl-beta-D-ribofuranose(ABR)afforded the corresponding N1-2,6-disubstituted nucleosides(2a,b)without any trace of the N3-isomer.The 2-methylthio-6-methyl derivative(2b)has then proved to be a key intermediate for the synthesis of N1-6-methyluridine(4)and the corresponding N1-2-amino-6-metyhl derivative(5),suggesting the possibility to obtain different 2,6-disubstituted derivatives by means of methylthio nucleophilic substitution.A successful solid phase application was also shown.