Synthesis, Characterization And Antiurease Activity Of3-(4-nitrophenyl) Acrylic Acid Complexes

Urease is widely found in fungi, bacteria and plants, and it is regarded as avirulent factor of many pathogenic microorganisms. It was the first enzyme shown tocontain two nickel ions in its catalytic center. The nickel ions played an important rolein catalyzing the hydrolysis of urea. Different urease have different structures. Butdue to the catalytic site displayed a highly conserved amino acid sequence, they mayhave the same catalytic mechanism. Helicobacter pylori is the main cause of somestomach diseases, and has been proved to have a direct relationship with gastriccancer. More and more evidence suggest that urease plays a key role whenHelicobacter pylori infecting the stomach, thus the research of urease inhibitorattracts people’s interest.Cinnamic acid is a natural product with a wide range of application in flavors,food additives and other aspects. With further study, cinnamic acid derivatives havebeen demonstrated to have many pharmacological effects such as antibacterial,antioxidant and anticancer activity. Metal coordination compounds such as cisplatinand carboplatin in addition to have an excellent anticancer activity, but also havevariety biological activities such as sterilization, anti-inflammatory and anti-virus.According to published papers, the transition metal complexes showed a good ureaseinhibitory activity.In this paper, we synthesized5new kinds of transition metal complexes using3-(4-nitrophenyl)acrylic acid, organic amine and cooper/nickel/zinc. All5complexeswere structurally determined by single X-ray analysis and FT-IR. Complex1is amononuclear complex which the nickel coordinates with3-(4-nitrophenyl)acrylic acid,N,N’-dimethylethylenediamine and3coordination water molecules (space group: P-1;cell parameters: a=6.2331(5), b=14.2263(11), c=15.0427(12), α=77.244(3)°,β=82.061(3)°, γ=81.259(3)°). Complex2is also a mononuclear complex which thenickel only coordinates with ethylenediamine and2cooridination water molecules(space group: C2/2; cell parameters: a=31.0943(17), b=6.5008(4), c=14.6306(8), α=90°, β=105.478(2)°, γ=90°). Complex3is a binuclear complex containing twocooper ions. Two oxygen atoms bridge the two symmetry-related copper and each copper coordinates with2nitrogen atoms from N,N’-dimethylethylenediamine and3oxygen atoms (space group: P-1; cell parameters: a=7.5763(7), b=8.0475(7),c=15.7825(14), α=77.404(3)°, β=76.433(3)°, γ=79.479(3)°). Complex4has thesimilar structure with complex2, the copper only coordinates with ethylenediamineand2coordination water molecules (space group: C2/c; cell parameters:a=31.0826(13), b=6.0511(3), c=14.6480(7), α=90°, β=105.535(2)°, γ=90°).Complex5is a mononuclear complex which the zinc coordinates with two3-(4-nitrophenyl)acrylic acid and1,2-propanediamine (space group: Pnma; cellparameters: a=6.0983(2), b=25.9204(9), c=13.9274(4), α=90°, β=90°,γ=90°).We evaluated the inhibitory activity of these5transition metal complexes onjack bean urease. The activity results suggest that all the5complexes showed acomparable or better urease inhibitory activity against the positive control(acetohydroxamic acid). Especially, complexes3and4have the best inhibitoryactivity against jack bean urease (IC50=1.23μM and1.17μM). This research showednew use of cinnamic acid and the activity data confirmed that transition metalcomplexes are potential inhibitors against urease.