Tian Xin-Chuan, Huang Xing, Wang Dan, Gao Feng
Department of Chinese Traditional Herbal, Agronomy College, Sichuan Agricultural University.
Chem Pharm Bull (Tokyo). 2014;62(8):824-9. doi: 10.1248/cpb.c14-00264. Epub 2014 Jun 10.
An efficient one-pot synthesis of quinazoline-2,4(1H,3H)-diones was developed. First, the reactions of anthranilic acid derivatives with potassium cyanate afforded the corresponding urea derivatives. Then, cyclization of the urea derivatives with NaOH afforded the monosodium salts of benzoylene urea. Finally, HCl treatment afforded the desired products in near-quantitative yields. This is an eco-efficient method because all the reactions were carried out in water, and the desired products were obtained simply by filtration. The aqueous filtrate was the only waste generated from the reaction. We scaled up the reaction to 1 kg starting material, thus establishing an alternative approach for the green synthesis of quinazoline-2,4(1H,3H)-diones in the chemical and pharmaceutical industries.
开发了一种高效的一锅法合成喹唑啉-2,4(1H,3H)-二酮的方法。首先，邻氨基苯甲酸衍生物与氰酸钾反应得到相应的脲衍生物。然后，脲衍生物与氢氧化钠环化得到苯甲酰脲的单钠盐。最后，用盐酸处理以近乎定量的产率得到所需产物。这是一种环境友好的方法，因为所有反应均在水中进行，所需产物只需通过过滤即可获得。反应产生的唯一废物是水性滤液。我们将反应扩大到1千克起始原料，从而为化学和制药行业中喹唑啉-2,4(1H,3H)-二酮的绿色合成建立了一种替代方法。
