Synthese von Carbazolderivaten, 1. Mitt.: Über die Reaktion von 3-(2-Nitroethenyl)indol-2-malonestern mit Michael-Akzeptoren

Synthesis of Carbazole Derivatives, I: Reaction of 3-(2-Nitroethenyl)-indole-2-malonic Acid Esters with Michael-Acceptors Michael-type reactions of compounds of type 9 were studied. Addition reactions with acrolein and methyl vinyl ketone, respectively, lead — depending on the conditions — to pyridoindoles of type 16 and 14 and/or to tetrahydrocarbazoles of type 17 and 15 . With Triton B compounds 15 undergo retro-Michael-type elimination of the nitromethyl group, followed by hydrolysis/decarboxylation and dehydrogenation, leading to the disubstituted carbazoles 20 . In the case of 17a , the primary elimination product 18 could be isolated. The synthetic potential of these reaction types is discussed. Some of the described compounds and derivatives of them show antimycobacterial activity.