Synthesis of new 7-benzothiazol-2-yl quinolone derivatives as antitumor agents

S. A. Hussein, H. Abd El Makso

Abstract

In this work, 3-benzothazol-2-yl-phenylamine(1)was synthesized through the reaction of 2-aminothiophenol and 3- aminobenzoic acid using polyphosphoric acid as dehydrating agent, and used as start for the preparation of the target compounds IV and V. Benzothiazolyl-phenylamine1was reacted with ethoxymethylene diethyl malonate ester (EMME) to afford compound II which was thermally cyclized in diphenyl ether to give 7-benzothizol-2-ylquinolone III. Benzaothiazolylquinolone IV was synthesized from the reflux of 7-benzothizol-2-ylquinolone III with POCl5. The nucleophillic substitution of chloride anion of 7-benzothizol-2-ylchloroquinolone IVwith p-toluidine was preceded by using anhydrous potassium carbonate in DMF. Compounds IV and V were screened for antitumor activity against breast carcinoma cell line (MCF-7). The IC 50% of compounds IV and V were 0.066 and 0.056 umol/mL respectively and showed high activity in comparison to 0.065 umol/mL standard A . The structure of the compounds IV and V was confirmed using IR, NMR, mass spectroscopy and elemental analysis.