Eine einfache Synthese von 5<i>H</i>-[1]Benzopyrano[4,3-<i>d</i>]pyrimidin-Derivaten mit Oxo-, Thioxo- und/oder Imino-Funktionen in 4- und 5-Stellung
作者:Detlef Briel、Siegfried Leistner、Günther Wagner
DOI:10.1055/s-1986-31504
日期:——
A Simple Synthesis of 5H-[1]Benzopyrano[4,3-d]pyrimidine Derivatives having Oxo-, Thioxo-, and/or Imino Functions at Positions 4 and 5 The reaction of 4-dicyanomethylene- or 4[cyano-(ethoxycarbonyl)-methylene]-2-(2-hydroxyphenyl)-4H-1, 3-benzoxazine with ammonium acetate, hydrogen sulfide, or aqueous acid represents a useful method for the preparation of 4,5-(imino, thioxo, or oxo)-disubstituted 2-(2-hydroxyphenyl)-3,4-dihydro-5H-[1]benzopyrano[4, 3-d]pyrimidines.
5H-[1]苯并吡喃并[4,3-d]嘧啶衍生物在4和5位具有氧代、硫代和/或亚氨基官能团的简单合成 4-二氰基亚甲基-或4[氰基-(乙氧羰基)-亚甲基]-2-(2-羟基苯基)-4H-1,3-苯并噁嗪与乙酸铵、硫化氢或水溶液的反应是制备4,5-(亚氨基、硫代或氧代)-二取代2-(2-羟基苯基)-3,4-二氢-5H-[1]苯并吡喃并[4,3-d]嘧啶的有效方法。