SINTESIS, UJI ANTIBAKTERI, DAN UJI SITOTOKSISITAS SENYAWA N-FENILPIRAZOLINA DARI 4-DIMETILAMINOBENZALDEHIDA DAN 4-KLOROASETOFENON

MUHAMMAD NURROHMAN SIDIQ, Dra. Tutik Dwi Wahyuningsih, M.Si, Ph.D ; Dr. Chairil Anwar

2015 | Skripsi | S1 KIMIA

Muhammad Nurrohman Sidiq 10/305289/PA/13479 INTISARI Telah dilakukan sintesis turunan N-fenilpirazolina yaitu N-fenil-3-(4-klorofenil)-5-[4-(dimetilamino)fenil]-2-pirazolina melalui sintesis kalkon dan siklisasi beserta uji aktivitas antibakteri dan uji sitotoksisitasnya. Sintesis kalkon dilakukan berdasarkan mekanisme reaksi kondensasi Claisen-Schmidt terhadap senyawa 4-dimetilaminobenzaldehida dan 4-kloroasetofenon pada temperatur kamar dengan katalis NaOH 40% (b/v). Selanjutnya kalkon direaksikan dengan fenilhidrazin dalam suasana basa NaOH 40% (b/v) sehingga meghasilkan N-fenilpirazolina. Produk hasil sintesis dielusidasi menggunakan spektrometer FTIR, GC-MS, 1H dan 13C-NMR. Senyawa N-fenil-3-(4-klorofenil)-5-[4-(dimetilamino)fenil]-2-pirazolina selanjutnya diuji aktivitas antibakterinya menggunakan metode difusi sumuran pada bakteri uji Gram positif (Staphylococcus aureus, Shigella flexnerri, dan Basillus subtilis) dan Gram negatif (Salmonella typhimurium, Bacillus cereus, dan Escherichia coli) serta DMSO 99% sebagai kontrol negatif dan tetrasiklin (100 ppm) sebagai kontrol positif. Senyawa tersebut kemudian diuji sifat sitotoksisitasnya menggunakan metode Brine Shrimp Lethality Test (BSLT) terhadap hewan uji larva Artemia salina untuk mendapatkan nilai median lethal concentration (LC50) yang dihitung menggunakan analisis probit. Reaksi kondensasi Claisen-Schmidt menghasilkan dimetilamino-kloro-kalkon yang berwujud padatan berwarna kuning dengan rendemen sebesar 63,74% sedangkan hasil siklisasi adalah N-fenilpirazolina yang berupa padatan hijau dengan rendemen 64,86%. Senyawa turunan N-fenilpirazolina menunjukkan aktivitas yang baik sebagai agen antibakteri pada bakteri Gram negatif. Aktivitas antibakteri terbaik pada konsentrasi terendah (100 ppm) ditunjukkan pada penghambatan pertumbuhan bakteri Escherichia coli. Uji sitotoksisitas senyawa turunan N-fenilpirazolina menunjukkan sifat toksik dengan LC50 sebesar 36,85 ppm.

Muhammad Nurrohman Sidiq 10/305289/PA/13479 ABSTRACT Synthesis of N-phenylpyrazoline derivative, N-phenyl-3-(4-chlorophenyl)5-[4-(dimethylamino)phenyl]-2-pyrazoline via stepwise chalcone's synthesis followed by cyclization, and bioassay (i.e antibacterial and cytotoxicity assay) have been done. Chalcone's synthesis based on Claisen-Schmidt's condensation mechanism between 4-dimethylaminobenzaldehyde and 4-chloroacetophenone was performed at room temperature in the presence of NaOH 40% (w/v). The chalcone was then reacted with phenylhydrazine under alkaline condition with NaOH 40% (w/v) catalyst to produce N-phenylpyrazoline. All of the products were analyzed using FTIR, GC-MS, 1H and 13C NMR spectrometers. N-phenyl-3-(4-chlorophenyl)-5-[4-(dimethylamino)phenyl]-2-pyrazoline was tested for its antibacterial activity using "well diffusion" methods on the Gram-positive bacteria (Staphylococcus aureus, Shigella flexnerri, and Basillus subtilis ) and Gram-negative (Salmonella typhimurium, Bacillus cereus, and Escherichia coli) bacteria with DMSO 99% as negative control and tetracycline as positive control. This compound has also been tested to prove it's cytotoxicity activity by "Brine Shrimp lethality Test" methods on Artemia salina leech to gain medium lethal concentration value (LC50) which was then calculated by probit statistical analysis. Claisen-Schmidt's condensation's product yielded yellow solid of dimethylamino-chloro-chalcone in 63.74%, while the cyclization product produced N-phenylpyrazoline as green solid in 64.86% yield. N-phenylpyrazoline derivate showed good antibacterial activity, especially on the Gram-negative bacteria. The best antibacterial activity at the lowest concentration (100 ppm) showed the inhibition of Escherichia coli's bacterial growth. Cytotoxicity assay of N-phenylpyrazoline showed that this compound has a toxic level at LC50 36,85 ppm.

Kata Kunci : kalkon, N-fenilpirazolina, antibakteri, sitotoksisitas