An Alternative Synthesis of 5-Aminopyrazolo[4,3-d]pyrimidin-7(6H)-one

Recently, the synthesis of 9-deazaguanine, pyrrolo[3,2-d]-pyrimidine ring system was developed by using the commercially available 2-amino-6-methylpyrimidin-4(3H)-one as a starting material, and this procedure was expected to be very efficient in synthesizing our target molecule. A variety of biological effects of formycin has led interests derivatives of. C-Nucleoside guanosine analogue 5-amino-3-(β-D-ribofuranosyl)-pyrazolo[4,3-d]pyrim-idin-7(6H)-one has been prepared from. However, the synthetic route using an initial ring opening of followed by a series of chemical transformation and subsequent ring closure afforded in poor overall yield