SYNTHESIS AND BIOLOGICAL EVALUATION OF A SERIES OF SUBSTITUTED PYRAZOLO [3,4-D]-1,2,3-TRIAZOLES AND PYRAZOLO[3,4-D]OXAZOLES

In view of the biological relevance of triazole-based heterocyclic str uctures as antifungal, antiviral, and antitumor agents, we have synthe sized a series of substituted pyrazolo[3,4-d]-1,2,3-triazoles (2e-h, 2 j, 4b) which we evaluated for their cytostatic and antiviral (HIV-1 in cluded) activity and for their capability to inhibit the multiplicatio n of various human pathogenic fungi and bacteria. Moreover, the biolog ical activities of a few compounds, namely pyrazolo[3,4-d]oxazoles (3a -e) and pyrazolo[3,4-d]-1,2,3-triazoles (2a-d, 4a, 5), previously obta ined by us but not investigated for their biological activity, were al so studied. Only compounds 3a-e were endowed with a significative anti proliferative activity on the human lymphoblastoid cell line MT-4 cell s. All pyrazole derivatives proved ineffective in protecting cell cult ures against the HIV-1-induced cytopathogenicity, and none of the comp ounds was active against the bacteria and fungi tested.