Synthesis of 1, 4 Benzothiazine Derivatives for Antimicrobial Activity

Compound (3-oxo-3, 4-dihydro-2H-1, 4-benzothiazin-2-yl) acetic acid was synthesized by reacting o-Amino thiophenol and maleic anhydride. (3-oxo-3, 4-dihydro-2H-1, 4-benzothiazin-2-yl) acetate was prepared by Esterification of (3-oxo-3, 4-dihydro-2H-1, 4-benzothiazin-2-yl) acetic acid. Further eight Mannich bases were synthesized by using substituted Aromatic amines. The structures of synthesized compounds were confirmed on basis of IR, NMR and Mass Spectra. All synthesized compounds were screened for their antibacterial activity against strains viz. E. coli, E.fecalis, Klebshilla and S. aureus and antifungal activity against strains viz. C. albican and Aspergillus Niger. [4-({[4-( N-(5-methyl-4,5-dihydroisoxazol-3-yl)-aminosulfonyl) phenyl] amino} methyl)-3-oxo-3,4-dihydro- 2H-1,4-benzothiazin-2-yl]acetic acid, Ethyl[4-({[4-(N-(5-methyl-4,5-dihydro isoxazol-3-yl)-aminosulfonyl)phenyl] amino} methyl)-3-oxo-3,4-dihydro-2H-1,4-benzo thiazin-2-yl]acetate, [4-({[4-(N-pyridin-aminosulfonyl) phenyl] amino} methyl)-3-oxo-3,4-dihydro-2H-1,4-benzothiazin-2-yl]acetic acid and Ethyl [4-({[4-(N-pyridin-aminosulfonyl) phenyl]amino}methyl)-3-oxo-3,4-dihydro-2H-1,4-benzothiazin-2-yl]acetate have shown significant antibacterial and antifungal activity, while other derivatives shown moderate antibacterial and antifungal activity.