indenoisoquinolines as topoisomerase inhibitors I useful as antineoplastic agents

摘要

A number of indenoisoquinolines were prepared and evaluated for cytotoxicity in human cancer cell cultures and for activity vs. topoisomerase I. The two most cytotoxic indenoisoquinolines proved to be cis-6-ethyl-5,6,12,13-tetrahydro-2,3-dimethoxy-8,9-(methylenedioxy)-5,11-dioxo-11H-indeno[1,2-c]isoquinoline and cis-6-allyl-5,6,12,13-tetrahydro-2,3-dimethoxy-8,9-(methylenedioxy)-5,11-dioxo-(11H)indeno[1,2-c]isoquinoline. Two of the most potent topoisomerase I inhibitors were 6-(3-carboxy-1-propyl)-5,6-dihydro-5,11-dioxo-11H-indeno[1,2-c]isoquinoline (26) and 6-ethyl-2,3-dimethoxy-8,9-(methylenedioxy)11H-indeno[1,2-c]isoquinolinium chloride (27). Two additional potent topoisomerase I inhibitors, 6-allyl-5,6-dihydro-2,3-dimethoxy-8,9-(methylenedioxy)-5,11-dioxo-11H-indeno[1,2-c]isoquinoline (13c) and 5,6-dihydro-6-(4-hydroxybut-1-yl)-2,3-dimethoxy-8,9-methylenedioxy-5,11-dioxo-(11H)indeno[1,2-c]isoquinoline (19a), did not unwind DNA and did not affect topoisomerase II.