10.1007/BF00479904
The research focuses on the synthesis of benzo[c]pyrilium salts with a cyclopolyether substituent and their conversion to isoquinoline derivatives. The key chemicals involved in the research include homoveratric acid and benzo-15-crown-5 as starting compounds. These compounds react in polyphosphoric acid to form ketone I. Carboxylic acid anhydrides, specifically acetic or propionic anhydride, along with perchloric acid, are used to convert ketone I into benzo[c]pyrilium perchlorates (IIa and IIb). Finally, ammonium carbamate is employed to transform these perchlorates into the desired isoquinoline derivatives (IIIa and IIIb). The study explores the potential of these compounds for developing new biologically active substances that can penetrate biological membranes or influence selective ion transfer in living organisms.