|摘要: ||在這份研究中，我們用以3,4,5-三甲氧基酚為起始物合成5,6,7-三甲氧基類黃酮的衍生物。而這些合成的類黃酮以清除1,1-diphenyl-2-picrylhydrazyl (DPPH)自由基能力、trolox 當量的抗氧化能力、抑制 liposome脂質過氧化試驗來評估這些化合物的抗氧化能力和抑制酪胺酶試驗來評估美白的效果。也以MTT毒性試驗來作類黃酮衍生物對B16-F0黑色素細胞的毒性。結果顯示出合成的類黃酮衍生物在清除DPPH自由基和脂質過氧化試驗中，抗氧化的能力皆很弱。在trolox 當量的抗氧化試驗中，化合物24在濃度為0.20 mg/ml時，清除率達79.9 %；化合物28在濃度為0.40 mg/ml時，清除率達76.86 %。在酪胺酸酶抑制中，化合物25、27及28在高濃度(0.20 mg/ml)下的抑制率在35%~40%左右。在毒性試驗中B環上的C4’位置接兩個碳的取代系列相對上比接三個碳的取代系列對黑色素細胞還不具有毒性上的傷害。|
In this report, 5,6,7-trimethoxy flavonoids derivatives were synthesized starting from 3,4,5-trimethoxyphenol. The synthesized flavonoids were also experiment for their antioxidant activities, evaluated using assays of 1,1-diphenyl-2-picrylhydrazyl (DPPH), trolox equivalent antioxidant capacity (TEAC), and inhibit liposome peroxidation methods. And they were also evaluated using assays of inhibit tyrosinase for skin-lightening. In the other, thery were experiments using the MTT assay to measure the effects of flavonoisd on cell cytotoxicity. In 1,1-diphenyl-2-picryl-Hydrazyl (DPPH) radical scavenging activity and inhibit liposome peroxidation methods, which free radical scavenging activity were very weak. In TEAC assay, compound 24、28 present more then 75% scavenging activity when the sample concentration were at 0.20 mg/mL and 0.40 mg/mL. In inhibit tyrosinase test, the inhibition activity of compound 25、27 and 28 were between 35% to 40% when the sample concentration were 0.20 mg/ml. In MTT assay demonstrated that the toxicity of three carbon more then two carbon substitute for B-ring of C’4 position on the flavonoids derivatives.