Synthesis and Antimicrobial Activity of Some 2-Alkyl-2H-1,4-benzothiazin-3(4H)-ones and 2-Alkylbenzoimidazolo-thiazolidin-3-ones

Article abstract of DOI:10.1007/BF00812716

Sodium 2-aminothiophenoxide (1) reacts with ethyl 2-bromoalkanoates (2) under direct cyclization to form 2-alkyl-2H-1,4-benzothiazin-3(4H)-ones (3).Reaction of the sodium salt of 2-mercaptobenzimidazole (4) with 2 or 2-bromoalkanoic acids (5) affords only S-alkylated products (6 or 7, respectively).The cyclization products - 2-alkylbenzoimidazolo<2,1-b>thiazolidin-3-ones (8) - can be obtained only from the corresponding 2-(2-benzimidazolylthio)alkanoic acids (7) by the action of acetic anhydride.Both compounds 3 and 8 exhibit only moderate antimicrobial activity against some gram-positive bacteria. - Keywords: 4H-1,4-Benzothiazines; Benzoimidazolo<2,1-b>thiazolidines; Antimicrobial activity.