Sintesis Turunan Khalkon Berbahan Dasar 4-Hidroksiasetofenon dan Uji Aktivitasnya sebagai Antioksidan

FERDHIANA ARIANIE SAFIRA, Dr. Winarto Haryadi, M.Si. ; Prof. Dr.rer.nat. Harno Dwi Pranowo, M.Si.

2022 | Skripsi | S1 KIMIA

Sintesis senyawa turunan khalkon berbahan dasar 4-hidroksiasetofenon dan uji aktivitasnya sebagai antioksidan telah dilakukan. Senyawa turunan khalkon disintesis melalui reaksi kondensasi Claisen-Schmidt menggunakan katalis basa dan pelarut metanol dengan metode konvensional dan sonokimia menghasilkan senyawa 4â��-hidroksi-3,4-dimetoksikhalkon (khalkon 1) dan 4â��-hidroksi-3,4-dimetoksi-6-nitrokhalkon (khalkon 2). Elusidasi struktur senyawa khalkon dilakukan menggunakan spektrometer FTIR, GC-MS, 1H dan 13C-NMR. Uji aktivitas antioksidan dilakukan dengan metode DPPH (2,2-difenil-1-pikrilhidrazil) dan BHT (butylated hydroxytoluene) sebagai kontrol positif. Hasil penelitian menunjukkan senyawa khalkon 1 berwujud padatan berwarna kuning dengan metode konvensional dan sonokimia dengan waktu reaksi 48 jam dan 90 menit menghasilkan rendemen berturut-turut 31,27% dan 36,93%. Senyawa khalkon 2 berwujud padatan berwarna kuning kunyit dengan metode konvensional dan sonokimia dengan waktu reaksi 48 jam dan 3,5 jam menghasilkan rendemen masing-masing 25,80% dan 22,31%. Hasil uji aktivitas antioksidan senyawa khalkon 1 dan khalkon 2 menghasilkan nilai IC50 berturut-turut 50,416 dan 18,809 �µg/mL yang dikategorikan sebagai antioksidan kuat dan sangat kuat. BHT sebagai kontrol positif dikategorikan sebagai antioksidan sangat kuat dengan nilai IC50 9,749 �µg/mL.

Synthesis of chalcone derivatives from 4-hydroxyacetophenone and its activity as antioxidant had been carried out. Chalcone derivatives were synthesized through the Claisen-Schmidt condensation reaction using base catalyst and methanol as solvent with conventional and sonochemical methods to produce 4â��-hydroxy-3,4-dimethoxychalcone (chalcone 1) and 4â��-hydroxy-3,4-dimethoxy-6-nitrochalcone (chalcone 2). The structure elucidation of all products was confirmed by FTIR, GC-MS, 1H and 13C-NMR spectrometers. Antioxidant activity test was carried out using DPPH method and BHT as positive controls. The results showed that chalcone 1 was a yellow solid using conventional and sonochemical methods with a reaction time of 48 hours and 90 minutes which yielded 31.27% and 36.93%, respectively. The compound chalcone 2 is a turmeric yellow solid using conventional and sonochemical methods with a reaction time of 48 hours and 3.5 hours, resulted in yields of 25.80% and 22.31%, respectively. The results of the antioxidant activity test of chalcone 1 and chalcone 2 gave IC50 values of 50.416 and 18.809 �µg/mL, which were categorized as strong and very strong antioxidants. BHT as a positive control was categorized as a very strong antioxidant with an IC50 value of 9.749 �µg/mL.

Kata Kunci : Antioksidan, hidroksiasetofenon, khalkon