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

A facile synthesis of 2,3-diaryl-cis-3, 3a-dihydropyrazolo [3',4':4,5] thiazolo [3,2-b]-s-triazoles (3) has been achieved by the condensation of 3-aryl-s-triazolo-5-thione (1) with chloroacetic acid and aldehydes in presence of acetic anhydride, anhyd sodium acetate and gl acetic acid to yield 2-aryl-6-arylidene thiazolo [3,2-b]-s-triazolo-5-(6H)ones (2) followed by treatment with arylhydrazines. The structures 3 were supported by IR and PMR spectral data. The appearance of two doublets (J=8.2 Hz) at delta 7.63 and 8.30 corroborates the cyclic structure and cis configuration. The antibacterial and antifungal activity of the system have also been evaluated.