Synthesis, Characterization and Antibacterial Study of Cinnamic Acid Derivatives

Cinnamic acids are a group of aromatic carboxylic acids found naturally in the plant kingdom. This group of molecules can be found in coffee beans, tea, cocoa, apples, citruses, and potatoes. Cinnamic acids possess outstanding biological and pharmacological activities. In this study, a series of known and new cinnamic acid ester derivatives (3-10) were synthesized by employing acyl halide esterification reactions. All the ester derivatives were characterized using analytical spectroscopic techniques including 1H & 13C Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FTIR). The synthesized compounds were evaluated in-vitro for their antibacterial activity against five different bacteria test strains, which were Gram-positive (Bacillus cereus, Staphylococcus epidermidis, and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria using the disk diffusion method. Among all of the synthesized compounds, derivative 3 exhibited the highest inhibitory activity against all the Gram-positive and Gram-negative bacteria. Most of the synthesized molecules in this study have not yet been reported in the literature, and thus may have biological activities worth investigating.