$$\hbox {Re}_{2}\hbox {O}_{7}$$ Re 2 O 7 -catalyzed formal [3 + 2] cycloaddition for diverse naphtho[1,2-b]furan-3-carboxamides and their biological evaluation
作者:Likai Xia、Akber Idhayadhulla、Yong Rok Lee
DOI:10.1007/s11030-015-9630-2
日期:2016.2
Diverse naphtho[1,2-b]furan-3-carboxamide derivatives 12a–12q were synthesized in high yield via the novel $$\hbox Re}_2}\hbox O}_7}$$ -catalyzed formal [3 $$+$$ 2] cycloaddition of 1,4-naphthoquinones with $$\beta $$ -ketoamides as the key step. This methodology offers several advantages, such as environmentally benign character, the use of a mild catalyst, high yields, and ease of handling. The synthesized compounds were screened for their tyrosinase inhibitory, antioxidant, and antibacterial activities. The results showed that compound 12c exhibited excellent tyrosinase inhibitory activity with an $$\hbox IC}_50}$$ of $$13.48\,\upmu \hbox g/mL}$$ , which is comparable to that of kojic acid ( $$\hbox IC}_50 }= 19.45\,\upmu \hbox g/mL}$$ ). Compounds 12a, 12b, and 12i displayed moderate antioxidant activities in a DPPH assay. Compound 12m showed good activity against S. aureus ( $$\hbox MIC} = 16\,\upmu \hbox g/mL}$$ ), and compound 12p was found to be active against E. coli ( $$\hbox MIC} = 16\,\upmu \hbox g/mL}$$ ).
通过新型$\textRe}_2\textO}_7$催化剂催化的1,4-萘醌与$\beta$-酮酰胺的关键[3+2]环加成步骤,高效合成了多种萘并[1,2-b]呋喃-3-羧酰胺衍生物12a–12q。该方法具有多个优势,如环境友好性、温和催化剂的使用、高产率及操作简便。合成的化合物被筛选用于酪氨酸酶抑制、抗氧化以及抗菌活性。结果显示,化合物12c表现出卓越的酪氨酸酶抑制活性,其$\textIC}_50}$为$13.48\,\mu\textg/mL}$,与曲酸的抑制效果($\textIC}_50} = 19.45\,\mu\textg/mL}$)相当。化合物12a、12b和12i在DPPH测试中显示出适度的抗氧化活性。化合物12m对金黄色葡萄球菌($\textMIC} = 16\,\mu\textg/mL}$)表现出良好的活性,而化合物12p则对大肠杆菌($\textMIC} = 16\,\mu\textg/mL}$)有活性。