Ultrasonic Promoted Regioselective Reactions of the Novel Spiro 3,1-Benzoxazon-Isobenzofuranone Dye Toward Some Organic Base Reagents

Abstract

Ultrasonic and solvent-free condensation of 2-aminobenzoic acid with 4-bromoisobenzofuran-1,3-dione to construct the 4′-bromo-3′H-spiro[benzo[d][1,3]-oxazine-2,1′-isobenzofuran]-3′,4(1H)-dione dye (1) under basic reaction conditions. The spiro product 1 exhibited both electrophilic and nucleophilic centers. A series of nitrogen nucleophiles such as hydrazine, glycine, 2-aminopyridine, pyridin-2-ylmethanamine, 4-methoxyaniline, 4-aminoacetophenone, morpholine, piperidine or 1-ethylpiperazine and carbon electrophiles such as oxiranylmethylchloride, ethyl chloroacetate, chloroacetyl chloride can be treated with 2-benzoxazine-2-yl benzoic acid (BBA) via multicomponent reaction. The fluorescence of the spiro product dyes decreases proportionally to the initial chloride concentration in the solution. The chemical structures of the synthesized compounds can be confirmed by microanalytical, spectral data and optimized by quantum chemical parameters. Biological evaluation showed that these synthesized spiro compounds exhibited moderate to good cytotoxic activity. Among them, compounds 2, 5, and 11 displayed the best cytotoxic activity against MCF7 and Wl-38 cell lines.