Homocamptothecin (hCPT) is a camptothecin (CPT) homologue with the insertion of a methylene (CH2) spacer between the alcohol moiety and carbonyl group of the classical six‐membered α‐hydroxylactone ring. This modification provides higher lactone stability and did not impair its activity against topoisomeraseI (Topo I), but rather appears to improve it compared to CPT. In an attempt to improve the