Background: In the present study, fourteen new 1,2,4-triazole Schiff bases and eight new
1,2,4-triazolo[3,4-b][1,3,4]thiadiazines incorporating a pyrimidine ring were synthesized and evaluated
for their antibacterial activity.
Methods: 1,2,4-Triazole Schiff bases were prepared from the condensation of 4-amino-3-mercapto-5-
(2-thiomethylpyrimidyl)-1,2,4-triazole with a series of arylaldehydes in the presence of (+)-tartaric acid
as catalyst. On the other hand, the reaction of 4-amino-3-mercapto-5-(2-thiomethylpyrimidyl)-1,2,4-
triazole with substituted phenacyl bromides afforded the corresponding 1,2,4-triazolo[3,4-b][1,3,4]-
Results: The structures of 1,2,4-triazole Schiff bases and 1,2,4-triazolo[3,4-b][1,3,4]thiadiazines were
characterized by IR, NMR and mass spectral data. All the synthesized compounds were screened for
their antibacterial activities using 96-well microbroth dilution assay.
Conclusion: Schiff base with p-hydroxylphenyl substituent and triazolothiadiazine containing 4-
flurophenyl ring displayed moderate antibacterial activity against Pseudomonas aeruginosa at MIC