Utilization of cinnamaldehyde for synthesis of nitrogen-containing 2-hydroxy-1,4-naphthoquinone derivatives as antioxidant agent

Cinnamaldehyde is the main compound in the cinnamon (Cinnamomum burmanii) that mostly applied in the essence and aroma industries and can be used as a medicinal product because of its bioactivities. This study aims to modify the cinnamaldehyde compound to 2-hydroxy-1,4-naphthoquinone derivatives containing nitrogen and test their bioactivity as an antioxidant. The synthesis of 2-hydroxy-1,4-naphthoquinone derivatives compounds was conducted which involves the precursors aromatic aldehyde variations (benzaldehyde, cinnamaldehyde, and 4-hydroxy benzaldehyde), and lawsone using iodine catalyst. The products were confirmed by UV-Vis, FTIR, and GC-MS obtained three 2-hydroxy-1,4- naphthoquinone derivatives, namely 2-(hydrazino-phenyl-methyl)-3-hydroxy-2,3-dihydro-[1,4]naphthoquinone (compound 1), 2-(1-hydrazino-3-phenyl-allyl)-3-hydroxy-2,3-dihydro-[1,4]naphthoquinone (compound 2), and 2-[hydrazino-(4-hydroxy-phenyl)-methyl]-3-hydroxy-2,3-dihydro-[1,4]naphthoquinone (compound 3) with yield 91.04, 82.62 and 87.22, respectively. IC₅₀ values of compounds 1 and 2 are 204.94 and 139.06, which indicates that compound 2 is more active in antioxidants than compound 1.