4-chloro-3 '-methylsulfinyl-5(6 or 8)-nitro-3,4 '-diquinolinyl Sulfides

Reaction of 4-chloro-3'-methylthio-3,4'-diquinolinyl sulfides 3, 9b, 9c wit h a nitrating mixture proceeds via the 3'-methylthio group monooxidation an d yields 3'-methylsulfinyl diquinolinyl sulfides 4, 5b, 5c, respectively. F urther treatment of 4 with a nitrating mixture followed as C-5- and C-8-nit ration and gives mixture of 5a and 5c. Treatment of 3'-methylsulfinyl quino lines 6 and 7 with hydrochloric acid / potassium iodide system causes reduc tion of the sulfoxide group in 6 and 7 to the sulfide group yielding 8, in case of 4-methoxyquinolines 6, hydrolysis of the 4-methoxyqninoline moiety to the 4-quinolinone moiety takes place simultaneously. The proton and carb on chemical shifts of 4 and 5a were completely assigned following COSY, HET COR and INEPT or COLOC studies.