title: Spectroscopic studies of DNA binding modes of cation-substituted anthrapyrazoles derived from emodin.
abstract: The DNA binding properties of three cation-substituted anthrapyrazole derivatives of emodin with calf thymus DNA were characterized by spectroscopic methods and the specific binding modes were elucidated. At low drug and high DNA concentrations, compound 1 with a mono-cationic amino side chain exhibited an intercalative binding mode, 2 with a much longer and more flexible di-cationic side chain exhibited an external binding mode, and 3 with a rigid di-cationic side chain exhibited both intercalative and external binding modes. The DNA binding mode of compounds was altered after structural modification. The molecular structure-DNA binding relationships found from this study may be useful for the design of anthrapyrazole derivatives with desired binding characteristics.
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510080, PR China.
authors.forename: Jia-Heng
authors.initials: JH
authors.lastname: Tan
authors.forename: Yu-Jing
authors.initials: YJ
authors.lastname: Lu
authors.forename: Zhi-Shu
authors.initials: ZS
authors.lastname: Huang
authors.forename: Lian-Quan
authors.initials: LQ
authors.lastname: Gu
authors.forename: Jian-Yong
authors.initials: JY
authors.lastname: Wu
mesh_terms: D018943:Anthracyclines / Q000378:metabolism; D002412:Cations; D002942:Circular Dichroism; D004247:DNA / Q000378:metabolism*; D004642:Emodin / Q000378:metabolism*; D004996:Ethidium / Q000737:chemistry; D008024:Ligands
chemical_list: D018943:Anthracyclines; D002412:Cations; D008024:Ligands; D004247:DNA; C055925:anthrapyrazole; D004996:Ethidium; D004642:Emodin