Abstract: The present invention relates to a method for synthesizing diversely substituted purines starting from a pyrimidine. Formula (I). The method comprises the formation of an amidine group on the pyrimidine by implementing a Vilsmeier type reagent, the functionalization of the pyrimidine with an amine and the cyclization to form the purine nucleus. Optional steps can also be performed in order to further functionalize the molecule. The invention also relates to new purines and new intermediate product.