SINTESIS DAN UJI AKTIVITAS ANTIBAKTERI SENYAWA N-ASETIL-PIRAZOLINA DARI p-ANISALDEHIDA DAN 4-HIDROKSIASETOFENON

ISNAINI YULIANTI C, Deni Pranowo, S.Si., M.Si.; Dra. Tutik Dwi Wahyuningsih, M.Si., Ph.D.

2015 | Skripsi | S1 KIMIA

Penelitian mengenai sintesis dan uji aktivitas antibakteri senyawa N-asetil-pirazolina dari p-anisaldehida dan 4-hidroksiasetofenon telah dilakukan.Penelitian bertujuan untuk mensintesis senyawa pirazolina dari p-anisaldehida dan 4-hidroksiasetofenon serta mengetahui aktivitas antibakterinya. Penelitian diawali dengan sintesis senyawa 1-(4-hidroksifenil)-3-(4-metoksifenil)-2-propen-1-on(kalkon 1) melalui reaksi kondensasi Claisen Schmidt antara p-anisaldehida dan 4-hidroksiasetofenon menggunakan katalis NaOH 40% dengan metode pengadukan selama 48 jam pada suhu ruang. Selanjutnya siklisasi kalkon menggunakan hidrazin monohidrat dan asam asetat glasial dilakukan untuk menghasilkan senyawa 3-(4-hidroksifenil)-5-(4-metoksifenil)-1-asetil-2-pirazolina (prazolina 1). Sintesisdilakukan dengan metode refluks selama 26 jam. Senyawa produk dianalisis menggunakan spektrometer FTIR, GC-MS, 1H- dan 13C-NMR. Uji aktivitas antibakteri senyawa pirazolina dilakukan dengan metode difusi sumuran terhadapbakteri Gram positif (Staphylococcus aureus, Bacillus cereus, danBacillus subtilis) dan Gram negatif (Escherichia colidan Shigella flexneri). Hasil penelitian yaitu produk kalkon1 berupa kristal kuning dengan titik leleh 94,1-96,9 C dan rendemen 88,19%. Produk senyawa pirazolina 1 berupa kristal tak berwarna (jernih) dengan titik leleh 215,7-216,9 C dan rendemen sebesar 64,52%. Uji aktivitas antibakteri menunjukkan bahwa senyawa pirazolina 1 memiliki aktivitas antibakteri terhadap bakteri Gram positif S. aureus (4,5/300 dan 4,5/500), B.cereus (6,5/300), B. subtilis (3,25/500 dan 3,5/1000) dan bakteri Gram negatif E. coli (5,25/1000). Senyawa pirazolina 1 tidak menunjukkan aktivitas antibakteri pada bakteri Gram negatif S. flexneri. Kata kunci : Kalkon, Pirazolina, p-Anisaldehida, Antibakteri

Synthesis and antibacterialtest of N-acetyl-pyrazoline have been carried out. Theaim of this research is to synthesis N-acetyl-pyrazolinefrom p-anisaldehyde and 4-hydroxyacetophenone and also to know its antibacterial activities. This research was begins by synthesis of 1-(4-hydroxy-phenyl)-3-(4-methoxy-phenyl)-2-propene (chalcone 1) via Claisen Schmidt condensation reaction between p-anisaldehyde and 4-hydroxyacetophenone using NaOH 40% as catalyst under stirring for 48 hours at room temperature. The next step was conducted by chalcone cyclization using hydrazine hydrate and glacial acetic acid to produce 3-(4-hydroxy-phenyl)-5-(4-methoxy-phenyl)-1-acetyl-2-pyrazoline (pyrazoline 1). The synthesis was conducted under reflux method for 26 hours. The product was analyzed using FT-IR, GC-MS, 1H- dan 13C-NMR spectrometer. Antibacterial test of pyrazoline compound was conducted by agar well diffusion method against Gram positive bacteria (Staphylococcus aureus, Bacillus cereus and Bacillus subtilis) and Gram negative bacteria (Escherichia coli and Shigella flexneri). The result showed that chalcone1 product was obtained as yellow crystal with melting point at 94.1-96.9 C and 88.19% yield. Then the cyclizationof chalcone produce pyrazoline 1as colorless crystal with melting point at 215.7-216.9 C in 64.52% yield. Antibacterial test show that pyrazoline 1 was active against selected Gram positive bacteria i.e. S. aureus (4.5/300 dan 4.5/500), B. cereus (6.5/300), B. subtilis (3.25/500 dan 3.5/1000) and Gram negative bacteria i.e. E. coli (5.25/1000). Pirazoline 1 was not active against Gram negative bacteria S. flexneri. Keywords: Chalcone, Pyrazoline, p-Anisaldehyde, Antibacterial activity

Kata Kunci : Kata kunci : Kalkon, Pirazolina, p-Anisaldehida, Antibakteri