Synthesis of 5-methyl-5H-pyrrolo[2,3-c]quinoline and 4-methyl-4H-pyrrolo[2,3-c]isoquinoline: two new unnatural D-ring stripped isomers of the cryptolepine series

5-Methyl-5H-pyrrolo[2,3-c]quinoline and 4-methyl-4H-pyrrolo[2,3-c]isoquinoline have been synthesized via a domino condensation - Heck cyclisation of, respectively, 4-bromoquinolin-3-amine or 4-bromoisoquinolin-3-amine and acetaldehyde. Selective methylation of the tricyclic skeletons yielded the title compounds 5-methyl-5H-pyrrolo[2,3-c] quinoline and 4-methyl-4H-pyrrolo[2,3-c] isoquinoline.