Study On The Sythesis And Antibacterial Properties Of Fumaric Acid Derivatives

Derivatives of fumaric acid have been extensively applied in the fields of food and medicine. So, research on the synthesis and antibacterial activity of fumaric acid and its derivatives is of great significance.Five n-monoalkyl fumarates and two alkyl p-nitrophenyl fumarates were synthesized and their antibacterial properties were studied.Five n-monoalkyl fumarates were prepared in the presence of catalysts by isomerization of the corresponding n-monoalkyl maleates, which were prepared by reaction of maleic anhydride with methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, respectively. The catalysts used for the isomerization are the corresponding fumaric acid n-monoalkyl monochlorides, which were prepared by reaction of n-monoalkyl fumarate with thioyl chloride. Fumaric acid monomethyl monochloride and fumaric acid monoethyl monochloride were reacted with p-nitrophenol to form methyl p-nitrophenyl fumarate and ethyl p-nitrophenyl fumarate, respectively. Conditions of the mentioned reaction were optimized. All the products were characterized by refractive index, melting point, IR, 1H-NMR or HPLC.The inhibition diameter and the minimal inhibition concentration of seven esters of fumaric acid on the twelve kinds of fungi and the inhibitory effects of five n-monoalkyl fumarates on mixed bacteria separated from sour milk were determined. The results showed that seven esters of fumaric acid have evidently bacteriostatic action on fungi mentioned above. Their inhibition on penicillium is the strongest. The alkyl p-nitrophenyl fumarates are the better bacteriostat. All of the seven esters of fumaric acid have good stability under heat treatment(121℃, 30min). When the concentration of the five n-monoalkyl fumarates is 2g/L, they have evidently bacteriostatic effect on the growth of the mixed bacteria separated from sour milk.