Condensed bridgehead nitrogen heterocyclic systems:: Synthesis, bioactivity and stereochemistry of pyrazolo [3′,4′:4,5][thiazolo [3,2-b]-s-triazoles

A facile synthesis of 2,3-diaryl-6-o-chiorophenyl-trans-3,3a-dihydropyrazolo [3',4: 4,5] thiazolo [3,2-b]-s-triazoles 3 has been achieved by the condensation of 3-ochlorophenyl-s-triazole-5-thione 1 with chloroacetic acid and aldehydes in the presence of acetic anhydride, anhyd sodium acetate and gl acetic acid to yield 2-o-chlorohenyl-6arylidene thiazolo [3,2-b]-s-triazol-5-(6H)-one 2 followed by treatment with arylhydrazines. The structures 3 were supported by IR and H-1 NMRspectral data. The appearance of two doublets (J=4.2Hz) at delta 7.98 and 8.07 corroborate the cyclic structure and trans configuration. The antibacterial and antifungal activities of the system have also been evaluated.