A new series of pyrazolopyrazinoselenolotriazolopyrimidines was synthesized by a facile method based on condensation of 5-amino-3-methyl-1-phenyl-1Hpyrazolo[3,4-b]selenolo[3,2-e]pyrazine-6-carbonitrile (3) with triethyl orthoformate followed by intramolecular cyclization with hydrazine to afford 7-amino-8-imino3-methyl-1-phenyl-1,8-dihydro-7H-pyrazolo[300,400:50 ,60 ]pyrazino[20 ,30 :4,5] selenolo [3,2-d]pyrimidine (5). The latter compound was utilized as a multipurpose precursor for the construction of other new triazoles fused to the pyrazolopyrazinoselenolopyrimidine moiety. Alternatively, acetylation and chloro-acetylation of compound 3 using acetic anhydride and chloroacetyl chloride yielded the acetyl amino 11 and chloroacetamido 12 derivatives, respectively. Compound 12 underwent nucleophilic substitution upon reaction with morpholine to provide the morpholinyl acetamide 13. Furthermore, the pyrazolopyridoselenolopyrazine ring system 14 was synthesized by the reaction of the o-amino-carbonitrile 3 with malononitrile. Assignment of the chemical structures for the new compounds was confirmed depending on elemental and spectral techniques. On the other hand, most of the synthesized compounds revealed promising results against various bacterial and fungal strains