Synthesis of new biologically active isothiazolo[4,5-b]carbazole-type tetracyclic derivatives via an indole-2,3-quinodimethane approach

A number of isothiazolo[4,5-b]carbazole derivatives were prepared via a Diels–Alder approach involving thermally induced indole-2,3-quinodimethane intermediates. Preliminary biological tests revealed a GSK-3β kinase inhibitor (29) and some free NH group containing compounds (17d, 19c, 29) displayed selective human carbonic anhydrase I inhibitory activities.

Figure optionsDownload as PowerPoint slide