申请人:Pharmacyclics, Inc.
公开号:US05601802A1
公开(公告)日:1997-02-11
Texaphyrin metal complexes having improved functionalization include the addition of electron-donating groups to positions 2, 7, 12, 15, 18 and/or 21 and/or the addition of electron-withdrawing groups to positions 15 and/or 18 of the macrocycle. Electron-donating groups at positions 2, 7, 12, 15, 18 and/or 21 contribute electrons to the aromatic .pi. system of the macrocycle which stabilizes the metal complex to demetallation and the imine bonds to hydrolysis. These texaphyrin metal complexes having enhanced stability are useful for localization, magnetic resonance imaging, radiosensitization, radiation therapy, fluorescence imaging, photodynamic therapy, RNA hydrolysis, DNA photocleavage, and applications requiring singlet oxygen production for cytotoxicity. Electron-withdrawing groups at positions 15 and/or 18 render the macrocycle more readily reduced, i.e. the redox potential is lower and the macrocycle more readily gains an electron to form a radical. Such texaphyrins having a low redox potential are useful for radiation sensitization applications.
Texaphyrin金属配合物的改进功能化包括在大环的2、7、12、15、18和/或21位添加电子给予基团,以及在15和/或18位添加电子吸引基团。在2、7、12、15、18和/或21位的电子给予基团向大环的芳香π系统提供电子,从而稳定金属配合物,使其不易去金属化并使亚胺键不易水解。这些具有增强稳定性的Texaphyrin金属配合物可用于定位、磁共振成像、放射增敏、放射治疗、荧光成像、光动力疗法、RNA水解、DNA光解和需要产生单线态氧以达到细胞毒性的应用。在15和/或18位的电子吸引基团使大环更容易还原,即其氧化还原电位更低,大环更容易获得电子形成自由基。这种具有低氧化还原电位的Texaphyrins可用于放射增敏应用。