Synthesis and antibacterial activity of some new thiazole and thiophene derivatives.

Dibenzobarrelene 1 was reacted with cyanoacetic acid hydrazide and thiosemicarbazide to give the corresponding 3-oxo-propiononitrile and thioamide derivatives 2 and 16, respectively. The base-catalyzed reaction 3-oxo-propiononitrile derivative 2 with phenyl isothiocyanate yielded the non-isolable intermediate 3. Treatment of 3 with dilute HCl afforded the corresponding thiocarbamoyl derivative 4. The intermediate 3, thiocarbamoyl 4 and thioamide derivatives 16 were utilized as key intermediates for the synthesis of some new thiazole 5, 6a, 6b, 7, 8, 10a, 10b, 12, 14a, 15, 17a, 17b, and 18; and thiophene 13a-d derivatives, respectively. The newly synthesized compounds were characterized by IR, (1)H NMR, (13)C NMR and mass spectral studies. Representative compounds of the synthesized product were tested and evaluated as antibacterial agent.