Synthesis and antimicrobial activity of N-alkyl substituted p-methyl (E)-3-and 4-azachalconium bromides

YAYLI N. , Misir G., Yayli N. , YAŞAR A. , demir E., DEMİRBAĞ Z.

TURKISH JOURNAL OF CHEMISTRY, cilt.34, ss.219-228, 2010 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 34 Konu: 2
  • Basım Tarihi: 2010
  • Doi Numarası: 10.3906/kim-0904-41
  • Sayfa Sayıları: ss.219-228


Twenty new N-alkyl substituted p-methyl (E)-3- and 4-azachalcones (1a-j, 2a-j) {3-[(1E)-3-(4-methylphenyl)-3-oxoprop-1-en-1-yl]-1-alkyl (C-5-12,C-14-15) pyridinium bromides (1a-j) and 4-[(1E)-3-(4-methylphenyl)-3-oxoprop-1-en-1-yl]-1-alkyl (C-5-12,C-14-15) pyridinium bromides (2a-j)} were synthesized and tested for antimicrobial activities against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Enterococcus faecalis, Proteus vulgaris, and Escherichia coli. They showed good antimicrobial activity especially against the gram-positive bacteria tested with minimal inhibitory concentration (MIC) values less than 4.7 mu g/mL in most cases. The optimum length of the alkyl chain for better and broader activity is situated in the range of 8-12 carbon atoms in the series of compounds 1a-j, 2a-j. The non-alkylated compounds 1-2 were not effective as were the ones alkylated with 14 or 15 C alkyl groups (1i, 1j, 2i, 2j). N-Alkyl derivatives of p-methyl (E)-3-azachalcone (1a-h) showed better activity in comparison to those of p-methyl (E)-4-azachalcone (2a-h). The antimicrobial activity increased as the length of the alkyl substitution increased from 5 to 12 carbons.