title: Photosensitizer in a molecular bowl: steric protection enhancing the photonuclease activity of copper(II) scorpionates.
abstract: Steric encumbrance caused by the tripodal ligand in the ternary tris(3-phenylpyrazolyl)borate copper(II) heterocyclic base complexes [Cu(B)(Tp(Ph))](ClO(4)) (B = dipyridoquinoxaline, dipyridophenazine) leads to efficient cleavage of supercoiled DNA to its relaxed form upon exposure to red light at 632.8 and 694 nm as a result of protection of the photosensitizer in the molecular bowl of the {Cu(Tp(Ph))} moiety, which generates singlet oxygen as the reactive species in a type-II process.
authors.affiliation: Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India.
authors.forename: Shanta
authors.initials: S
authors.lastname: Dhar
authors.forename: Akhil R
authors.initials: AR
authors.lastname: Chakravarty
mesh_terms: D003300:Copper / Q000737:chemistry*; D004247:DNA / Q000187:drug effects / Q000378:metabolism; D003851:Deoxyribonucleases / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D006571:Heterocyclic Compounds / Q000737:chemistry; D008024:Ligands; D008027:Light; D009942:Organometallic Compounds / Q000737:chemistry*; D017319:Photosensitizing Agents / Q000494:pharmacology*
chemical_list: D006571:Heterocyclic Compounds; D008024:Ligands; D009942:Organometallic Compounds; D017319:Photosensitizing Agents; D003300:Copper; D004247:DNA; D003851:Deoxyribonucleases