The synthesisfrom 3-thiochromanone of indole and quinoline derivatives is reported. The structures of the compounds obtained, which are analogs of carcinogenicnitrogen polycycles, were determined by means of mass spectrometry and high resolution NMR spectrometry. In the latter case, Nuclear Overhauser Enhancements (NOE) allow the unequivocal determination of structures. Furthermore, direct (or“through