Synthesis of Isoflavones and Study on Tyrosinase Inhibitory effect

• Main Authors: Yen-Pin Hsieh, 謝燕萍
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/83985646446148451670

碩士 === 大仁科技大學 === 製藥科技研究所 === 100 === Eight isoflavones were synthesized by one-pot approach and tested to find out the inhibiting effect to mushroom tyrosinase and B16F10 cell viability . These isoflavones were 7,8-dihydroxylated and 5,7-dihydroxylated series based on the ring A system with various ring B substitution. 7,8- dihydroxylated series includes 7,8-Dihydroxyisoflavone (1), 7,8-Dihydroxy- 4''-methoxyisoflavone (2), 7,8-Dihydroxy-3''-methoxyisoflavone (3) and 3'',7,8-Trihydroxyisoflavone (4). 5,7-dihydroxylated series includes 5,7-Dihydroxyisoflavone (5), 5,7-Dihydroxy-4''-methoxyisoflavone (6), 5,7-Dihydroxy-3''-methoxyisoflavone (7), and 3'',5,7-Trihydroxyisoflavone (8). All the structures of compounds were identified by spectroscopic and confirmed by comparing with literature data. The results showed that isoflavones are effective mushroom tyrosinase inhibitors, especially the 7,8-dihydroxylated series (1-4) has the best inhibitions. Among the isoflavones, the potency of IC50 in 7,8-Dihydroxy-4''-methoxyisoflavone (2) at 30min and 60min are 50.88±1.80 μM & 51.83±4.61 μM and IC50 in 7,8-Dihydroxy-3''-methoxyisoflavone (3) for 53.87 ± 11.91 μM and 54.20± 9.21 μM exhibited most notable inhibiting activities, three times in potency of arbutin (IC50=154.02 ± 6.32 μM & IC50=146.20 ± 8.32 μM). In addition, these synthesized isoflavones had lower cytotoxic after they had been cultivated for 24 hours and then tested for the viability in the murine melanoma celllines (B16F10). The minimum cell viability of these isoflavones was found to be 60.38 ± 1.23% treated with 80μM of 3. The others were found to be up to 75%. The results showed that the presented isoflavones combined with ortho dihydroxylated ring A combined with lipophilic ring B have good tyrosinase inhibition. Therefore, 7,8-dihydroxylated isoflavones could be potential candidates for new ingredients of tyrosinase inhibitors.