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Benzaldehyde [4‐(4‐bromophenyl)thiazol‐2‐yl]hydrazones 5a–5d were prepared by reacting the thiosemicarbazones 2a–2d with 2,4′‐dibromoacetophenone (1) in absolute ethanol. Acetylation of 5a and 5b with Ac₂O/Py at room temperature gave the N‐acetyl derivatives 6a and 6b. 4‐Methyl‐2‐pentanone/cyclopentanone [4‐(4‐bromo‐phenyl)thiazol‐2‐yl]hydrazones (8a) and (8b) were similarly obtained from the reaction of 1 with the thiosemicarbazones 7a and 7b, respectively. Cyclization of D‐galactose thiosemicarbazone (9) and its tautomers 10 and 11 with 1 afforded an equilibrium mixture of the acyclic 2‐thiazolylhydrazone 12, together with its respective cyclic galactosyl derivatives 13 and 14, whose structures were studied by using ¹H and ¹³C NMR spectra. The antimicrobial activity of the synthesized thiazole derivatives was evaluated in vitro by using an agar diffusion technique, and some of these …