Synthesis Characterization and Antibacterial, Antifungal Activity of N-(Benzyl Carbamoyl or Carbamothioyl)-2-hydroxy Substituted Benzamide and 2-Benzyl Amino-Substituted Benzoxazines Academic Article uri icon

abstract

  • New N-(benzyl carbamothioyl)-2-hydroxy substituted benzamides13,20, and21were synthesized using sodium bicarbonate and benzyl amine with 2-thioxo-substituted-1,3-benzoxazines6, 10a, b, 11c, and12a–n. The 2-thioxo-substituted-1,3-oxazines6, 10a-b, 11d 12a–n, and26were converted to the corresponding 2-methylthio-substituted-1,3-oxazines14a–land24which were then converted to 2-benzyl amino-substituted-benzoxazines15a–iby refluxing with benzylamine. Products15a, b, e, f, andgwere also synthesized by boiling the corresponding N-(benzyl carbamothioyl)-2-hydroxy substituted benzamides13a, b, f, l, andmin acetic acid. 2-Oxo-substituted-1,3-benzoxazines22and25were prepared by treating the corresponding 2-methylthio-substituted-1,3-oxazines14and24with dilute HCl. The N-(benzyl carbamoyl)-2-hydroxy substituted benzamide23was synthesized from the reaction of 2-oxo-substituted-1,3-benzoxazine22with benzylamine. The new products were characterized using IR,1H, and13C NMR in addition to microanalysis. Selected compounds were tested in vitro for antibacterial and antifungi activity and the most active compounds were found to be the 4-(substituted-benzylamino)-2-hydroxy benzoic acids9aandd(M. chlorophenolicum, MIC 50 and 25 µgm L−1, resp.),N1,N3-bis (benzyl carbamothioyl)-4,6-dihydroxy-substituted phthalamides20aand20c(B. subtilisMIC 12.5, 50 µgm L−1, resp.) and21(M. chlorophenolicum, MIC 50 µgm L−1).

publication date

  • 2013