Table 2.

Molecular docking data for CP derivative, topotecan, and etoposide against human Topo I (PDB: ID 1K4T) and Topo IIβ (PDB: ID 7YQ8).

Compound	Target	Binding Affinity (Kcal/mol)	Amino Acid Residue DNA Nucleotide Base	Types of Interaction
Topotecan	Topo I	−10.26	LYS 532 ASP 533 ARG 364 GLU 365 DC 112 DA 113 TGP 11 DT 10	H-bond H-bond H-bond Pi-Anion Pi-Pi Pi-Pi Pi-Pi Pi-Pi
CP derivative	Topo I	−12.04	TRP 416	H-bond
			ASN 419	H-bond
			ARG 375	Pi-Anion
			DG 112	Pi-Alkyl
			LYS 425	Pi-Alkyl
			GLU 356	Halogen
			ASP 533	Pi-Anion
			DA 113	Pi-Pi
			TGP 11	Pi-Pi
			DT 10	Pi-Pi
			HIS 632	Pi-Alkyl
			ILE 535	Pi-Alkyl
			ILE 420	Pi-Alkyl
			LYS 374	Pi-Alkyl
			PHE 361	Pi-Alkyl
Etoposide	Topo IIβ	−8.62	DC 28 DG 27 DG 23 ARG 508 PRO 824 MET 787	H-bond Pi-Pi Pi-Pi Pi-cation Pi-Alkyl Pi-Alkyl
CP derivative	Topo IIβ	−8.01	GLY 638 SER 485 GLU 482 GLY 483 PRO 824 ASP 562 DC 28 DG 27 DG 323	H-bond H-bond Halogen Halogen Pi-Alkyl Negative-Negative H-bond Pi-Pi Pi-Pi