Condensation of schiff bases with compounds containing labile hydrogen atoms

Development of the catalytic synthesis of compounds of the quinoline series (the N. S. Kozlov reaction) (Review)*

“…On the basis of the obtained amino derivatives new mono-and bisazomethines of the 4,7-phenanthroline series 33-35 were synthesized. The condensation of azomethines with cyclic ketones [45][46][47][48][49][50][51][52] deserves special attention since it makes it possible to insert cyclopentane and cyclohexane rings, which are fragments of a series of natural compounds (steroids, alkaloids, prostaglandins) exhibiting cytotoxic, antitumor, pesticidal, and other types of activity, into the azaphenanthrene molecule. 3-Aryl-substituted 4,7-phenanthrolines 36 annelated with a cyclopentane or cyclohexane ring were synthesized by boiling arylmethylidene-6-quinolylamines with cyclopentanone and cyclohexanone in n-butyl alcohol in the presence of concentrated HCl [53,54].…”