Vol. 11 | No. 4 |1765 - 1770| October - December | 2018 ISSN: 0974-1496 | e-ISSN: 0976-0083 | CODEN: RJCABP http://www.rasayanjournal.com http://www.rasayanjournal.co.in Rasayan J. Chem., 11(4), 1765-1770(2018) http://dx.doi.org/10.31788/RJC.2018.1143051 SYNTHESIS AND ANTIOXIDANT ACTIVITY OF PRENYLATED RESVERATROL Tagor Marsillam Siregar 1,2,* , Emil Budianto 2 , Herry Cahyana 2 and Widajanti Wibowo 2 1 Laboratory of Chemistry, Food Technology Department, Faculty of Science and Technology, Universitas Pelita Harapan, Lippo Karawaci, Tangerang 15811, Indonesia 2 Postgraduates Program, Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok 16424, Indonesia *E-mail : tagor.siregar@uph.edu ABSTRACT Resveratrol derivatives have been reported to have important bioactivities. Synthesis of monomeric resveratrol derivatives has been a challenging topic in both organic and medicinal chemistry. A Synthesis of prenylated resveratrol was developed through prenylation between resveratrol (3,5,4'-trihydroxystilbene) and prenyl bromide (3,3-dimethyl allyl bromide) using heterogeneous superbase catalyst γ-Al2O3/NaOH/Na. The aim of this research is to obtain prenylated resveratrol compound that has important bioactivity and to identify a type of prenylation, O- or C-prenylation. Characterization of the product was carried out using liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance ( 1 H-NMR). The antioxidant activity of the samples was determined using DPPH radical scavenging assay. The results of LC-MS analysis of the product showed the molecular ion peak at m/z 365.38 [M+H] + that indicated the presence of prenylated resveratrol with two prenyl (C5H9-) substituent. The 1 H-NMR spectrum of the product indicated that the addition of two prenyl substituent occurs at the hydroxyl group on the structure of resveratrol (O-prenylation). Prenylation caused decreasing free radical scavenging activity of the product (IC50 = 102,75 ppm) compared to resveratrol (IC50 = 63,52 ppm) and it means that the addition of prenyl substituents occurs through O-prenylation. Keywords: Antioxidant activity, Prenylation, Prenyl bromide, Prenylated resveratrol, Resveratrol, Superbase catalyst γ-Al2O3/NaOH/Na © RASĀYAN. All rights reserved INTRODUCTION Resveratrol (3,5,4'-trans-trihydroxystilbene) and its derivatives belong to a group of plant polyphenolic compound “stilbene”, which has a molecular structure in the form of two phenyl rings linked by an ethylene bridge 1 . Resveratrol and its derivatives have been found in particular families of plants including Vitaceae, Dipterocarpaceae, Gnetaceae, Cyperaceae, Leguminosae, Moraceae, Pinaceae and Polygonaceae 2-10 . The biosynthesis of resveratrol in-plant is catalyzed by stilbene synthase. Resveratrol that has formed subsequently undergo structure modifications through glycosylation, methylation, oligomerization, isomerization, and prenylation generate various resveratrol derivatives with intriguing chemical diversity 11-16 . Resveratrol derivatives have been reported to have important bioactivities. Therefore, Synthesis of monomeric resveratrol derivatives has been a challenging topic in both organic and medicinal chemistry. In recent years, a number of catalytic methods have been developed to generate chemical diversity synthetically 16,17 . Prenylation plays a major role in the diversification of aromatic natural products, such as phenylpropanoids, flavonoids, and coumarins 18 . Prenylation is a chemical or enzymatic addition of a hydrophobic isoprenoid side chain to an accepting molecule such as a flavonoid or polyhydroxy aromatic compound 19 . Polyphenols such as flavonoid and stilbenoid have been reported to possess isoprenoid group on its structure 20 . These prenylated polyphenols have diverse and significant