N-benzoylindole-2,3-quinodimethane: Diels-Alder reactivity and synthetic applications for [b]annellated indoles
摘要:
The Diels-Alder reactivity of in situ generated N-benzoylindole-2,3-quinodimethane has been expanded considerably to include reactions with carbon- and hetero-dienophiles which furnish a variety of [b]annellated indoles as well as functionalized and annellated carbazoles. The frontier molecular orbital theory was found to be a useful model for the prediction of the experimental results under consideration of reactivity aspects.
New potential DNA intercalators of the carbazole series from indole-2,3-quinodimethanes: Synthesis, crystal structure, and molecular modeling with a watson-crick mini-helix
1-Alkylpyrano[3,4-b]indol-3-ones 3 react via a Diels-Alder step with an aryne or N-phenylmaleimide to furnish the new [b]annellated carbazoles 4-10 in a one-pot process. In an analogous procedure, the in situ generated N-benzoylindole-2,3-quinodimethane (13) reacted with quinones to furnish the dioxocarbazoles 14-16. Compounds 4 8 and 14-16 with a coplanar skeleton are members of a class of potential DNA intercalators, as has been shown for 5 and 8 by X-ray structural analysis. On the basis of the geometries determined by X-ray crystallography, the intercalative binding of these molecules with a Watson-Crick mini-helix was predicted by molecular modeling methods,