Synthesis and antibacterial properties of nitrofuryltriazolothiadiazepines

Methyl aryl ketones I on reaction with 5-nitrofurfuraldehyde 2 give 1-aryl-3-(5-nitro-2-furyl)-2-propen- I -ones 3 which on bromination affords 2,3-dibromo- I -aryl-3-(5-nitro-2-furyl)-2-propen- I -ones 4. Debromination of 4 by triethylamine in benzene results in 1-aryl-3-(5-nitro-2-furyl)-2-propen- 1 -ones 5 which on condensation with 3-substituted-4-amino-5-mercapto-1,2,4-triazole 6 furnishes Michael adducts 7. The Michael adduct 7 undergoes cyclization in conc. sulphuric acid to give 3-aryloxymethyl-6-aryl-8-(5-nitro-2-furyl)-1,2,4-triazolothiadiazepines 8. Antibacterial activity of 7 and 8 has been reported.