An Efficient Synthesis and Antimicrobial Studies of Bioactive 4H-1,4-Benzothiazine and Their Sulfone Derivatives

Abstract

4H-1,4-benzothiazines were prepared by condensation followed by oxidative cyclization of substituted 2-aminobenzenethiols with β-diketones in dimethylsulfoxide. On refluxing with 30% hydrogen peroxide in glacial acetic acid, 4H-1,4-benzothiazines yielded 4H-1,4-benzothiazine-1,1-dioxides. Structural evaluation has been done by spectral and elemental analysis. All the synthesized compounds were evaluated for their antibacterial and antifungal activity and all these have shown moderate to high activity against the test microbes.

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GRAPHICAL ABSTRACT

Keywords:

• 4H-1,4-benzothiazine
• heterocycles
• sulfones and antimicrobial activity

Acknowledgments

Authors are thankful to the Department of Chemistry and the Department of Botany, University of Rajasthan, Jaipur (India) for providing laboratory facilities. Authors are also thankful to Central Drug Research Institute, Lucknow (India) for providing IR, NMR, and Mass spectra. UGC Research Award Scheme, New Delhi is duly acknowledged for financial support.