POLYCYCLIC QUINOLONES (PART 2) - SYNTHESIS OF NOVEL 4-OXO-1,4-DIHYDROBENZO[h][1,3]THIAZETOI3,2-a]QUINOLINE CARBOXYLIC ACIDS VIA OXIDATIVE CYCLIZATION OF THE CORRESPONDING 2-MERCAPTOQUINOLINE PRECURSORS

摘要

The first synthesis of a series of 4-oxo-1,4-dihydro-benzo[h][1,3]thiazeto[3,2-a]quinoline carboxylic acids and their esters via oxidative cyclization of ethyl 2-((2-ethoxy-2-oxoethyl)thio)-4-hydroxybenzo-[h]quinoline-3-carboxylate derivatives in the presence of a vicinal dihaloalkane, KI, and K2CO3 is described. Structures of the synthesized compounds were characterized by spectrometric and X-ray crystallographic analyses.