Design, Synthesis, and Antimicrobial Evaluation of Novel [1,2,4]Triazolo[3,4-b][1,3,4]thiadiazepine Derivatives

Abstract

The title compounds, 3,3′,3″,3′′′-[methylenebis(oxybenzene-5,1,3-triyl)]tetrakis(6,8-diaryl[1,2,4]triazolo[3,4-b][1,3,4]thiadiazepines), were synthesized starting from dimethyl 4-hydroxyisophthalate which was reacted with dibromomethane to obtain tetramethyl 5,5′-[methylenebis(oxy)]di(benzene-1,3-dicarboxylate). The latter was treated with excess hydrazine hydrate, and the resulting tetrahydrazide was converted to tetrakis-1,2,4-triazolyl derivative via cyclization with ethanolic potassium hydroxide, carbon disulfide, and hydrazine hydrate. In the final stage, cyclocondensation with substituted chalcones afforded the target products. The structure of the newly synthesized compounds was confirmed by elemental analyses and FT-IR and NMR spectra, and their antimicrobial activities against some bacterial and fungal strains were estimated by the disc diffusion method.