A New Synthetic Framework for 11‐Demethylellipticine

A new synthetic route for the synthesis of 5‐methyl‐6 H ‐pyrido[4,3‐ b ]carbazole ( 8 ), so‐called 11‐demethylellipticine, was described. Construction of the tetracyclic structure hexahydro‐1 H ‐pyrido[4,3‐ b ]carbazol‐5(6 H )‐one skeleton ( 6 ) was also achieved by nucleophilic substitution reaction in the synthetic route. Also new tetrahydrocarbazole derivatives ( 2 , 3 , 4 , and 5 ) were synthesized. Several ellipticine analogs and octahydropyridocarbazole‐based G‐protein coupled receptors inhibitors can also be synthesized from tetracyclic structure ( 6 ) because of carbonyl functionality at position 5.