化学学报 ›› 1965, Vol. 31 ›› Issue (6): 502-508. 上一篇    下一篇

5-羟基嘧啶——Ⅳ.5-烷氧基-5-烷基-2-硫代巴比酸和有关化合物的合成

黄湘舲, 周政, 陶鏡蓉, 錢瑞卿, 陸大荇, 王真, 陈立滇, 伍少蘭, 張滂   

  1. 北京大学化学系
  • 投稿日期:1964-11-20 发布日期:2013-06-03

5-HYDROXYPYRIMIDINES Ⅳ. SYNTHESIS OF 5-ALKOXY-5-ALKYL-2-THIOBARBITURIC ACIDS AND RELATED PYRIMIDINES

HUANG SIANG-LIN, CHOW CHENG, TAO CHIN-YUNG, CHIEN RAY-CHIN, LU TA-HSIN, WANG CHEN, CHEN LI-TIEN, WU SHAO-LAN, P. CHANG   

  1. Departmem of Chemistry, Peking University
  • Received:1964-11-20 Published:2013-06-03

自烷氧基乙酸乙酯的乙氧草酰化,继以热裂去羰化反应,合成了一系列烷氧基丙二酸二乙酯(Ⅵ,R=n-C3H7,n-C4H9,iso-C4H9,iso-C5H11和C6H5CH2);进一步烷基化,得到烷氧基烷基丙二酸二乙酯(Ⅶ,R'=CH3,C2H5,n-C3H7n-C4H-9)。烷氧基烷基丙二酸二乙酯(Ⅶ)与脲、硫脲和与胍的缩合的容易程度相差颇巨。除苯甲氧基乙基丙二酸二乙酯曾与脲缩合生成相应的5,5-二取代巴比酸(I,Y=O)外,其他的各烷氧基烷基丙二酸二乙酯(Ⅶ)均未能与脲顺利地发生缩合。各烷氧基烷基丙二酸二乙酯(Ⅶ)与硫脲的缩合效果较佳,但其中仍有若干未能得到所期望的2-硫代巴比酸(I,Y=S)。两个系列的烷氧基烷基丙二酸二乙酯(Ⅶ,R=n-C3H7和C6H5CH2;R'=CH3,C2H5,n-C3H7,和n-C4H9)与胍的缩合非常顺利,生成相应的5,5-二取代-2-亚氨基巴此酸(I,Y=NH)。5-苯甲氧基-5-烷基-2-亚氨基巴比酸还进行了氢解,得到相应的5-羟基-5-烷基-2-亚氰基巴比酸(I,R=H,R'=烷基,Y=NH)。

This paper reports a synthetic study in the condensation of ethyl alkoxy-alkylmalopates with urea, thiourea, and guanidine. Ethyl alkoxymalonates (Ⅵ,R=n-C3H7,n-C4H9,n-C4H9,i-C5H11 and C6H5CH2) were pre-pared from the corresponding ethyl alkoxyacetates by ethoxalylation with subsequent pyrolytic decarbonylation. Various Ⅵ were then alkylated by standard method to give homologous ethyl alkoxy-alkylmalonates (Ⅶ,R'=CH3,C2H5,n-C3H7 and n-C4H-9). The ease with which ethyl alkoxy-alkylmalonates (Ⅶ) condense with urea, thiourea, and guanidine under the standard conditions promoted by sodium ethoxide varies considerably. All but one ethyl alkoxy-alhlmalonate (Ⅶ,R=n-C6H5CH2;R'=CH3,C2H5,n-C2H5) which gave a low yield of 5-alkoxy-5-alkylbarbituric acid (Ⅰ, Y=O) failed to react with urea.