SINTESIS DAN UJI AKTIVITAS ANTIBAKTERI SENYAWA TURUNAN N-FORMIL-2-PIRAZOLINA TERSUBSTITUSI GUGUS HIDROKSI DARI p-ANISALDEHIDA; SYNTHESIS AND ANTIBACTERIAL ACTIVITY TEST OF HYDROXYL SUBTITUTED N-FORMYL-2-PYRAZOLINE FROM p-ANISALDEHYDE
Arifani, Pramita S R, Tutik Dwi Wahyuningsih
2015 | Skripsi | FMIPA UGMSynthesis of N-formyl-2-pyrazoline derivative and test of its antibacterial activity have been carried out. The synthesis of pyrazoline was performed via cycloaddition of 1-(2,4-dihydroxyphenyl)-3-(4-methoxyphenyl)-2-propen-1-on (chalcone) by reaction with hydrazine monohydrate in acidic condition. Chalcones was synthesized from Claisen Schmidt condensation of p-anisaldehyde with 2,4-dihydroxyacetophenone. Chalcone was synthesized from p-anisaldehyde using KOH 40% (w/w) at room temperature for 48 hours. Synthesis of 1-formyl-3-(2,4-dihydroxyphenyl)-5-(4-dimethoxyphenyl)-2-pyrazoline was performed by refluxing chalcone and hydrazine monohydrate in the presence of formic acid for 6 hours. All the synthesized compounds were characterized using FTIR, GC-MS, 1H- and 13C-NMR spectrometers. Further, pyrazolines was screened for their antibacterial activities by agar well-diffusion against Gram positive (Staphylococcus aureus, Bacillus cereus, Bacillus subtilis) and negative (Eschericia coli, Shigella flexneri) bacterial, tetracycline (100 ppm) as positive control and dimethylsulfoxide (DMSO 99.9%) as negative control. The result showed that chalcone has been succesfully synthesized in 38% yield. Furthermore, the cycloaddition reaction yielded the pyrazoline 88% and showed significant antibacterial activity against Gram-positive bacterial and Gram negative bacterial. The highest activity showed by its zone of inhibitions(mm)/concentration(ppm) against B. subtillis (5.25/500) and Gram-negative S. flexneri (3.25/100).
Kata Kunci : N-formyl-2-pyrazoline; chalcone; p-anisaldehyde, antibacterial
