title: Photodynamic properties of a bispyrrolecarboxamide-modified hypocrellin B: the role of affinity and ascorbic acid.
abstract: The photodynamic properties of a new hypocrellin B (HB) derivative bearing a bispyrrolecarboxamide pendant (HB-Net) were investigated in detail. EPR experiments revealed that the generation ability of reactive oxygen species (ROS) of HB-Net is inferior to that of HB. DNA melting temperature measurements and ethidium bromide (EB) displacement assay illustrated the affinity of HB-Net toward dsDNA as the result of the bispyrrolecarboxamide unit, which is structurally related to the well-known minor groove binder netropsin. The radical generation abilities of HB and HB-Net can be enhanced by ascorbic acid via the photoinduced electron transfer from ascorbic acid to the photosensitizer, however, only the DNA photodamage capability of HB-Net can be improved significantly by ascorbic acid due to the stronger affinity of HB-Net to DNA. Consequently, the combination of HB-Net and ascorbic acid may lead to efficient DNA photodamage even in anaerobic conditions.
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Liu
authors.forename: Qianxiong
authors.initials: Q
authors.lastname: Zhou
authors.forename: Zhanghua
authors.initials: Z
authors.lastname: Zeng
authors.forename: Rui
authors.initials: R
authors.lastname: Qiao
authors.forename: Xuesong
authors.initials: X
authors.lastname: Wang
authors.forename: Baowen
authors.initials: B
authors.lastname: Zhang
mesh_terms: D000577:Amides / Q000737:chemistry*; D001205:Ascorbic Acid / Q000737:chemistry*; D004247:DNA / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D004996:Ethidium / Q000737:chemistry; D010569:Perylene / Q000031:analogs & derivatives* / Q000737:chemistry; D010778:Photochemotherapy; D011809:Quinones / Q000737:chemistry*; D013696:Temperature
chemical_list: D000577:Amides; D011809:Quinones; D010569:Perylene; D004247:DNA; D004996:Ethidium; D001205:Ascorbic Acid; C064522:hypocrellin B