Synthesis and antibacterial activity of novel unsaturated diastereomeric (E and Z) sulphur compounds

N. Penchalaiah, R. Mallikarjun

Abstract

The addition of p-chlorobenzenethiol to benzyl p-bromophenylketone resulted in the formation of a mixture of diastereomers (E)- and (Z)-1-p-bromophenyl-2-phenyl-1-p-chlorophenylthioethylene (1 and 2). These compounds on reaction with bromine in acetic acid yielded a mixture of (E)- and (Z)-1-bromo-2-p-bromophenyl-1-phenyl-2-pchlorophenylthioethylenes (5a and 5b). Oxidation of 5a and 5b affords (E)- and (Z)-1-bromo-2-p-bromophenyl-1- phenyl-2-p-chlorophenylsulphonylethylenes (6a and 6b), which on reaction with the p-chlorobenzenethiol gave (E)- and (Z)-1-p-bromophenyl-1-p-chlorophenylsulphonyl-2-phenyl-2-p-chlorophenylthioethylenes (7a and 7b). Upon oxidation of 7a and 7b yielded (E)- and (Z)-1,2-bis(p-chlorophenylsulphonyl)-2-phenyl-1-p-bromophenylethylenes (8a and 8b). The configurations of these compounds were established by elemental analysis, IR, 1H NMR and mass spectra, and by their preparation from p-bromobenzylphenylketone and p-bromophenylphenylacetylene. All these new compounds exhibited pronounced in vitro antibacterialActivity