[DNA intercalators. 1. Development of 2-hydroxy-benzo(b)carbazole derivatives as cytostatics]

Reaction of p-benzoquinone 3 and aminomethylene indanones 2 via easily oxidized benzocarbazoles 4/5 affords the heterocyclic quinones 6. The structure of 4/5 and 6 is proven by derivatization to 7b and 8b. The product 9 obtained by methylation of 6 is hydrogenated to 10 or debenzylated to 11. Ether cleavage yields 12. Reaction of 9 with lithium-methyl or NaBH4 affords 13 and the intermediates 14 and 15. Phenol 6a was alkylated to 16 or aminomethylated to 17 or 18. The indole quinones 17 and 18 show strong cytotoxic activity against colon cells and pulmonary carcinoma cells.