Chemical and enzyme-catalysed synthesis of quinoline arene hydrates

Arene hydrates of quinoline have been synthesized by enzyme-catalysed benzylic and allylic hydroxylation of dihydroquinolines in growing cultures of the fungus Mortierella isabellina and in liver microsomal preparations. A preference for allylic hydroxylation was generally observed in eukaryotic systems. Evidence of epoxidation of dihydroarenes by both the fungal and animal enzyme systems was also obtained. The chemical synthesis of these arene hydrates (5-hydroxy-5,6-dihydroquinoline, 6-hydroxy-5,6-dihydroquinoline, 7-hydroxy-7,8-dihydroxyquinoline, and 8-hydroxy-7,8-dihydroquinoline) from the corresponding hydroxy-5,6,7,8-tetrahydroquinolines, has also been accomplished.