Synthesis And Biological Test Of ?-Conjugated Tetra-aryl Porphyrins

Porphyrin and its derivatives play an important role in the life activities.They have been widely used in biomedicine,materials,catalysis and actinic fields,especially in diagnosis and photodynamic therapy?PDT?for cancer due to their unique photoactivity.This thesis includes main parts as follow:1.The research development of porphyrin compounds,including the structure,synthetic methods,interaction mode with DNA and their applications were reviewed.Meanwhile,the recent study of?-conjugated porphyrins and water-soluble porphyrins were briefly described.In this context,the design of this thesis was presented.2.The five?-conjugated cationic porphyrins were synthesized by string?,?^'-bromoporphyrin and excess vinyl compounds using a three-step cascade reaction?involving Heck reaction,six-?electrocyclization,and subsequent aromatization?,followed by a methylation reaction?coordinate reaction?.The synthesized porphyins and their intermidiates were characterized by UV,IR,¹H NMR and MS spectrum.After the fused aromatic ring was introduced in?,?^'position of porphyrin,the conjugation degree of system will increase.3.The interaction mode of porphyrin and DNA was studied by UV-vis and fluorescence spectroscopy.The results show that Por 1 adopts the outside stacking and outside binding manner with DNA,Por 2 with intercalative interaction mode,Por3 and Por 4 with outside binding mode,while Por 5 may interact with DNA using the outside binding and intercalative mode.4.With H₂TPP as a control,the singlet oxygen?¹O₂?generation of five porphyrins was tested through 1,3-diphenylisobenzofuran?DPBF?method.The results indicate the synthesized porphyrins show the higher ¹O₂ quantum yield than that of H₂TPP.Finally,the DNA cleavage ability of the five?-conjugated porphyrins was evaluated by the gel electrophoresis,with an order Por 2>Por 5>TMPyP>Por3>Por 1.Impressively,Por 2 could cleave 95.7%DNA when its concentration was adjusted to 2?M.In summary,the?-conjugated cationic porphyrin 2 and 5 was expected to be used as a potential photosensitizer due to the strong interaction with DNA and good DNA cleavage ability,which will provide a basic fundation for the following research.