Abstract

Background: Indane-1,3-dione, thiazole, bis-thiazole and thiadiazoles rings are very interested moieties in anti-inflammatory and analgesic drugs.

Objective: The goal of this work is to synthesize new derivatives of bis-thiazoles and bis-1,3,4- thiadiazoles for the investigation of their anti-inflammatory, anti-ulcerogenic and analgesic activities.

Methods: 1,1'-(1,2-phenylene)bis(3-phenylthiourea) (1) reacts with a number of N-aryl arenecarbohydrazonoyl chlorides 2 to give a series of new bis-1,3,4-thiadiazoles 4. Also, reaction of bisthiosemicarbazone of 1,3-indanedione 6 with another type of hydrazonoyl halides namely, N-aryl-2- oxapropanehydrazonoyl chlorides 7 and ethyl-(N-arylhydrazono)chloroacetate 8 in dioxane under reflux in the presence of triethylamine give the respective bis-thiazole derivatives 9 and 10, respectively. The products 9 and 10 can exist in five and seven tautomeric forms for each one. Their actual tautomeric forms were deduced based on electronic absorption data (UV / Vis spectra). Moreover, a series of novel bis-formazans 12 and 13 have been synthesized by reaction of 1,3-dihydrazono-2,3- dihydro-1H-indene (11) with both hydrazonoyl chlorides 7 and 8.

Results: The structure of all the novel products was deduced by elemental analysis and spectral data. In addition, the biological activity of the newly synthesized compounds was evaluated and the results obtained indicate their potency as anti-inflammatory, anti-ulcerogenic and analgesic agents.

Conclusion: In this context, we synthesize new derivatives of bis-thiazoles and bis-1,3,4-thiadiazoles as anti-inflammatory, anti-ulcerogenic and analgesic agents.

Keywords: Indane-1, 3-dione, thiosemicarbazone, bis-formazans, bis-thiazoles, anti-inflammatory activity.

Graphical Abstract