In vitro antioxidant properties of new thiazole derivatives

A series of novel N2-[2-chloro-4(3,4,5-trimethoxy phenyl azetidin-1-yl]-N4-(substituted aryl)-1,3-thiazole-2,4-diamine (4a–g) were synthesized starting from 3,4,5-trimethoxy benzaldehyde thiosemicarbazone (1). The compound (1) was obtained by condensing 3,4,5-trimethoxy benzaldehyde with thiosemicarbazide in methanol. 3,4,5-Trimethoxy benzaldehyde thiosemicarbazone (1) on treatment with chloracetyl chloride afforded 4-chloro-[2-(3,4,5-trimethoxy benzylidine) hydrazinyl]-1,3-thiazole (2). Compound (2) was reacted with chloracetyl chloride and triethylamine to obtain the corresponding 4-chloro-N-[2-chloro-4(3,4,5-trimethoxy phenyl) azetidin-1-yl]-1,3-thiazole-2-amine (3). Various substitutions on compound 3 with secondary amines yielded series of compounds (4a–g). The newly synthesized compounds were characterized by IR, 1H NMR, elemental analysis and mass spectral studies. All the compounds were screened for their in vitro antioxidant properties. The IC50 values of compounds 3 and 4a–g revealed that some of the synthesized compounds were showing potent antioxidant activity.