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camptothecin

An alkaloid isolated from the Chinese tree Camptotheca acuminata, with antineoplastic activity. During the S phase of the cell cycle, camptothecin selectively stabilizes topoisomerase I-DNA covalent complexes, thereby inhibiting religation of topoisomerase I-mediated single-strand DNA breaks and producing potentially lethal double-strand DNA breaks when encountered by the DNA replication machinery. (NCI)
Synonym:(+)-Camptothecin
20-(S)-camptothecine
camptothecine
Chemical structure:(S)-4-ethyl-4-hydroxy-1H-pyrano-[3',4':6,7]indolozino[1,2-b]quinoline-3,14(4H,12H)-dione
1H-pyrano[3',3'.6,7]indolizino[1,2-b]quinoline-3,14(4H,12H)-dione, 4-ethyl-4hydroxy-(S)-(9CI)
21, 22-secocamptothecin-21-oic acid lactone
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