Synthesis and molecular recognition of the role of the \
|School||Peking Union Medical College , China|
|Keywords||picket fence porphyrin derivative Molecular Recognition Solvent effect|
The palisade (Picket fence) porphyrin surrounded by protected form a hollow cages cavity structure, when the axial ligand bonded to the porphyrin ring plane, in addition to the role of the center of the axial ligand, the axial ligand and fence additional interaction between the cavity of a cage structure, this additional role will strengthen the fence porphyrin systems molecular recognition ability. Previous studies showed that the cage structure is not only having an identification of neutral molecules, and has a strong role in the anion. The amino acid as an integral part of the biological protein having good biocompatibility and a specific biological function. Thus, to the porphyrin compounds in the introduction of amino acids as the biocompatibility of the fence structure can enhance the synthesis of porphyrin systems. For this purpose, we have designed and synthesized amino acids \In this thesis, the Boc protected amino acid as a palisade structure, using the DCC condensation method, synthesis of 5 kinds of \And as the host molecules to explore their F - sup>, Cl - sup>, Br - sup>, I - sup>, H 2 SO 4 - sup>, AcO - sup>, H 2 PO 4 - sup> seven types of anion recognition behavior. The results show that the model compounds of this series has a strong role in identifying anion binding constants of 10 5 sup>. Magnitude. These seven anions of different compounds on F - sup>, Cl - sup> ions exhibit selective recognition behavior. Metal ion embedded porphyrin ring center have very important physiological activity. To Boc protected glycine \Taking into account Cl - sup> as the human body, the only anion channel, has a very important physiological role, it is selected to study as a guest molecule. Its free-base porphyrin compounds also have to identify the role of Cl - sup> (addition to the copper porphyrin outside). Free base porphyrin in six different polar solvents (toluene, tetrahydrofuran, dichloromethane, acetonitrile, ethanol, and tetrahydrofuran - water (1:1 v / v)) in order to investigate the recognition mechanism, Cl - sup> identifying behavior. Experimental results show that: in an aprotic solvent, such as toluene, tetrahydrofuran, dichloromethane and acetonitrile have a strong bonding ability, in a protic solvent, such as ethanol and tetrahydrofuran - water (1:1 V / V) change is not detected in the mixed solvent, UV - visible titration spectra. Therefore can be drawn: This compound is a hydrogen bond to the main force of the model compound, because of ethanol and tetrahydrofuran - water (1:1 V / v) mixed solvent of water molecules in the available excess of hydrogen bonds, alternative Cl - sup> with the fence in the interaction between the amide bond, and thus in these two solvents is not bonded Cl - sup>. This result suggests that the hydrogen bonding interactions between Boc protected amino acids \, \A cooperative binding of oxygen biologically relevant model will reveal the most simple structure to meet required for synergistic, but also contribute to a better understanding of the hemoglobin allosteric control the energy required. This article was successfully prepared a through ester bond links the ligand containing four pivaloyl fence structure \Existing synthetic model compounds closer bonding mechanism of hemoglobin, the exploratory simulation hemoglobin four heme cooperative binding of oxygen to provide more meaningful basis of theoretical exploration process, the study of artificial blood substitutes.