Synthesis and Characterization of Proton Transfer Salts of 2-Aminobenzothiazole Derivatives

Abstract

In this study, (E)-4-oxo-4-(3-sulfamoylphenyl)amino)but-2-enoic acid (Habsmal) was first obtained from the reaction of maleic anhydride (mal) with 3-aminobenzenesulfonamide (abs). Then, salts of 2-aminobenzothiazole (abt) (1) and 2-amino-6-ethoxybenzothiazole (EtOabt) (2) were synthesized by Habsmal. In addition, proton transfer salts were obtained from the reactions of 5-sulfosalicylic acid (H3ssa) with 2-amino-6-hydroxybenzothiazole (HOabt) (3) and 2-amino-6-nitrobenzothiazole (NO2abt) (4). The structures of proton transfer salts obtained in amorphous state have been proposed by elemental analysis, NMR (1H and 13C), FT-IR, charge balance and previous studies. According to the results of this analysis, the acid and base association ratios were found to be 1:1