Investigation of the lactam side chain length necessary for optimal indenoisoquinoline topoisomerase I inhibition and cytotoxicity in human cancer cell cultures.
Indenoisoquinolines with lactam substituents such as ethylamino, propylamino, and butylamino have previously demonstrated potent biological activity, but an optimal length has never been established. In the present study, a series of simplified indenoisoquinoline analogues possessing a linker spacing of 0-12 carbon atoms between the lactam nitrogen and the terminal amino group have been prepared, determining that 2-4-atom lengths are optimal for topoisomerase I inhibition and cytotoxicity. Using these lengths, analogues were prepared with the amino group and portions of the linker replaced by a pyridine ring. A three-carbon spacer within the pyridine series still demonstrated potent topoisomerase I inhibition.
Morrell
Andrew
A
Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy and Pharmaceutical Sciences, and the Purdue Cancer Center, Purdue University, West Lafayette, Indiana 47907, USA.
Placzek
Michael S
MS
Steffen
Jamin D
JD
Antony
Smitha
S
Agama
Keli
K
Pommier
Yves
Y
Cushman
Mark
M
D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D007192:Indenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D007546:Isoquinolines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D007769:Lactams / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D008958:Models, Molecular; D011725:Pyridines / Q000737:chemistry; D059004:Topoisomerase I Inhibitors
D000970:Antineoplastic Agents; D007192:Indenes; D007546:Isoquinolines; D007769:Lactams; D011725:Pyridines; D059004:Topoisomerase I Inhibitors