Anti-tyrosinase, antioxidant, and antibacterial activities of novel 5-hydroxy-4-acetyl-2,3-dihydronaphtho[1,2-b]furans

作者：Xia Likai; Idhayadhulla Akber; Lee Yong Rok^*; Wee Young Jung; Kim Sung Hong

来源：European Journal of Medicinal Chemistry, 2014, 86: 605-612.

DOI：10.1016/j.ejmech.2014.09.025

• Dihydronaphtho[1,2-b]furans
• CAN
• Formal [3+2[ cycloaddition
• Anti-tyrosinase
• Antioxidant
• Antibacterial

Novel 5-hydroxy-4-acetyl-2,3-dihydronaphtho[1,2-b]furans (7a-k) were synthesized using ceric ammonium nitrate (CAN)-catalyzed formal [3 + 21 cycloaddition. Synthesized compounds were evaluated for their tyrosinase inhibitory, antioxidant, and antibacterial activities. A modified spectrophotometric method using L-DOPA as substrate was used to determine tyrosinase inhibitory activities, and a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was used to evaluate antioxidant properties. Antibacterial activities against gram-negative Escherichia colt (KTC-1924) and gram-positive Staphylococcus aureus (KTC-1916) were evaluated using the disc diffusion technique. Of the synthesized compounds, 7b with a 4-acetyl and an electron-enriched dihydronaphthofuran ring showed the highest tyrosinase-inhibition activity (IC50 = 8.91 mu g/mL), which was comparable with that of standard kojic acid (IC50 = 10.16 mu g/ mL), potent antioxidant activity (IC50 = 3.33 mu g/mL), which was comparable with that of BHT (IC50 = 34.67 mu g/mL), and excellent antibacterial activities (MICs: 0.50 mu g/mL against E. coli and S. aureus strains). A mechanistic analysis of 7b demonstrated that its tyrosinase inhibitory activity was reversible and competitive. Compounds 7c and 7d showed potent antioxidant activities (IC50: 6.30 and 5.01 mu g/mL), and compound 7d also exhibited potent inhibitory activity against E. coli with a MIC of 0.5 mu g/mL. Furthermore, compounds 7a, 7e, 7f, and 7i showed potent antibacterial activities against S. aureus with MICs of 0.5 mu g/mL, which was comparable to that of ampicillin (MIC = 0.5 mu g/mL).

• 出版日期2014-10-30