A selective process is described for producing monohalogenated derivatives of 7-hydroxy coumarin wherein the halo substituent is at the desired position and the final product is free of other monohalogenated isomers. The resulting products, especially those wherein the halo substituent is at the 8 position, have valuable specific coronary vasodilating activity.
                            描述了一种选择性过程,用于生产单卤代衍
生物的7-羟基
香豆素,其中卤代取代基位于所需位置,并且最终产物不含其他单卤代同分异构体。得到的产物,特别是卤代取代基位于8位的产物,具有有价值的特定冠状动脉扩张活性。