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Purine analogues are well known for their importance in biological applications as antimetabolites [1], especially in the treatment of cancer and viral diseases. Also, purines are widely used in the CNS stimulation in vivo [2-10], antagonists, antiviral, antibacterial [1, 11] and in the treatment of gout [12]. Also, pyrazolopyrimidine systems are reported as inhibitors for the synthesis of DNA and RNA in the cells of some kinds of cancers [13] and viruses [14, 15].