Synthesis and antioxidant activity of some novel Fluorobenzothiazolopyrazoline

 A series of 7-chloro-N-(1-(7-chloro-6-fluorobenzo[d]thiazol-2-yl)-5-substituted phenyl-4,5- dihydro-1H-pyrazol-3-yl)-6-fluorobenzo[d]thiazol-2-amine (5a-f) have been synthesized by treating 4-fluoro-3-chloro aniline with KSCN in presence of bromine in glacial acetic acid and ammonia to get 7-chloro-6-fluorobenzo[d]thiazol-2-amine (1), which was treated with hydrazine hydrate in HCl in presence of ethylene glycol to get 7-chloro-6-fluoro-2- hydrazinylbenzo[d]thiazole (2). Alternatively compound 1 was treated with acetic anhydride to get N-(7-chloro-6-fluorobenzo[d]thiazol-2-yl)acetamide (3) which were used to synthesized a series of chalcones via Claisen-Schmidt condensation by using six different substituted aromatic aldehydes to get N-(7-chloro-6-fluorobenzo[d]thiazol-2-yl)-3-substituted phenyl acrylamide (4af). Finally the above chalcones were refluxed with compound 2 to get the novel targeted compound (5a-f). All the compounds were characterized by melting point, TLC and their chemical structures were proved by means of IR, 1 H NMR, mass spectroscopy, and elemental analysis data. All the final compounds and chalcones have been evaluated in vitro for their antioxidant activity by ferric ion reduction and DPPH methods. The final compounds have shown significant antioxidant activity compared to chalcones

Author(s): Kuntal Hazraa , L.V.G. Nargunda, P. Rashmia, J.N. Narendra Sharath Chandraa and B. Nandhab

Abstract | PDF

Share This Article