3′‐Methylsulfinyl‐3,4′‐diquinolinyl sulfides

Reactions of 4‐methoxy‐ or 1,4‐dihydro‐4‐oxo‐3′‐methylthio‐3,4′‐diquinolinyl sulfides 1 and 7 with a nitrating mixture ran as the 3′‐methylthio group 5‐mono‐oxidation followed by C 6 ‐ and C 8 ‐nitration and led to the mixture composed of products 3, 4, 5 and 6 (in the case of substrate 1 ) or compounds 5 and 6 (for substrate 7 ). In the reaction with hydrochloric acid 4‐methoxy‐3′‐methylsulfinyl‐3,4′‐diquinolinyl sulfides 3 and 4 could be hydrolysed to 3′‐methylsulfinyl‐4(1 H )‐quinolinones 5 or 6 respectively, the methylsulfinyl group remaining unaffected.