Synthesis, characterization and evaluation biological activity of some new Ethyl-2-amino benzothiazole -6- carboxylate derivatives

Abstract

In the current study aimed to investigate a number of heterocyclic compounds 4-
amino benzoate (procaine) (A1), where the ester was synthesized by esterification of 4-amino
benzoic acid with ethanol. Then, this compound was treated with potassium thiocyanate,
followed by oxidative cyclization of the produced thiourea with bromine solution to afford
ethyl-2-aminobenzothiazole-6-carboxylate (A2). The produced compound was further treated
with some substituted benzaldehyde yielding the Schiff bases (A3a-d). Compound (A2) was
also treated with acetic anhydride giving the corresponding N-(ethyl-2-amino benzo
thiazolyl-6-carboxylate acetamide (A4). Compound (A4) was allowed to react with hydrazine
hydrate afforded 2- benzothiazolyl-6- hydrazido acetamide (A5),which was then condensed
with substituted aromatic aldehydes affording 6-[(arylidine hydrazino)-carbonyl]-2-
acetamidobenzothiazole as a final product (A6a-d).
All the synthesized compounds were characterized by the Infrared (FT-IR) technology. Some
of the studied samples were checked by either their elemental analysis, (CHNS), 1H-NMR
method, and biological evaluations antibacterial activities for some of the synthesized imides
were evaluated against four types of bacteria and in addition to systematic identification of
some actives functional groups in these compounds