7-Cycloalkylcamptothecin derivatives: Preparation and biological evaluation

A series of 7-cycloalkylcamptothecin derivatives were synthesized from camptothecin with two methods. Their biological activities in vitro were evaluated with sulforhodamine-B (SRB) method on four types of human tumor cell lines A549/ATCC, HT29, NCI-H460 and HL60. Most of these camptothecin analogues show higher antitumor activity than the reference compounds SN-38 and Topotecan, with the IC(50) values low to nM level. Structure-activity relationship studies of these compounds mostly match the conclusion we achieved before from quantitative structure-activity relationship (QSAR) research.