1231941-80-2Relevant academic research and scientific papers
Acetylene bridged porphyrin-monophthalocyaninato ytterbium(iii) hybrids with strong two-photon absorption and high singlet oxygen quantum yield
Ke, Hanzhong,Li, Wenbin,Zhang, Tao,Zhu, Xunjin,Tam, Hoi-Lam,Hou, Anxin,Kwong, Daniel W. J.,Wong, Wai-Kwok
, p. 4536 - 4543 (2012/07/02)
Several acetylene bridged porphyrin-monophthalocyaninato ytterbium(iii) hybrids, PZn-PcYb, PH2-PcYb and PPd-PcYb, have been prepared and characterized by 1H and 31P NMR, mass spectrometry, and UV-vis spectroscopy. Their photophysical and photochemical properties, especially the relative singlet oxygen (1O2) quantum yields and the two-photon absorption cross-section (σ2), were investigated. These three newly synthesized compounds exhibited very large σ2 values and substantial 1O2 quantum yields upon photo-excitation, making them potential candidates as one- and two-photon photodynamic therapeutic agents.
Computational design and elaboration of a de novo heterotetrameric a-helical protein that selectively binds an emissive abiological (porphinato)zinc chromophore
Christopher Fry,Lehmann, Andreas,Saven, Jeffery G.,Degrado, William F.,Therien, Michael J.
, p. 3997 - 4005 (2010/05/15)
The first example of a computationally de novo designed protein that binds an emissive abiological chromohore is presented, in which a sophisticated level of cofactor discrimination is pre-engineered. This heterotetrameric, C 2-symmetric bundle, AHis:BThr, uniquely binds (5, 15-di[(4-carboxymethyleneoxy)phenyl]porphinato)zinc [(DPP)Zn] via histidine coordination and complementary noncovalent interactions. The A2B 2 heterotetrameric protein reflects ligand-directed elements of both positive and negative design, including hydrogen bonds to second-shell ligands. Experimental support for the appropriate formulation of [(DPP)Zn: A His:BThr]2 is provided by UV/visible and circular dichroism spectroscopies, size exclusion chromatography, and analytical ultracentrifugation. Time-resolved transient absorption and fluorescence spectroscopic data reveal classic excited-state singlet and triplet PZn photophysics for the AHis:BThr:(DPP)Zn protein (K fluorescence = 4 x 108 s-1; τtriplet = 5 ms). The A2B2 apoprotein has immeasurably low binding affinities for related [porphinato]metal chromophores that include a (DPP)Fe(III) cofactor and the zinc metal ion hemin derivative [(PPIX)Zn], underscoring the exquisite active-site binding discrimination realized in this computationally designed protein. Importantly, elements of design in the AHis:BThr protein ensure that interactions within the tetra-α-helical bundle are such that only the heterotetramer is stable in solution; corresponding homomeric bundles present unfavorable ligand-binding environments and thus preclude protein structural rearrangements that could lead to binding of (porphinato)iron cofactors.
