Abstract: Isoflavonoids are recognized to possess broad biological activities, such as cardiovascular, estrogenicity and so on.3-Pheny l-4(¹H)-quinolinone derivatives are isosteres of isoflavonoids and they have similar spatial structures.So perhaps they can exhibit similar activities.5- Chloro-6-fluro-3-phenyl-4-(¹H)-quinolinone derivatives and 7-chloro-6-fluro-3-phenyl-4- (¹H)-quinolinone derivatives were desig ned and synthesized at the same time.It's difficult to separate them due to their similar polarity.Only two isomeres (4a, 4b)were separated. 1, 2, 3 were mix tures due to their similar polarity of the two corresponding isomeres.The structures were confirmed by ¹H NMR and the contents of the mixtures were determined by HPLC.

Key words: 3-phenyl-4-(¹H)-quinolinone, Derivatives, ¹H NMR, Cardiovascular activity