Complex formation of nucleic acids with 5-[4′-(2″-amino-6″-oxo-1″H-purin-8″-yl)phenyl]-10,15,20-tris(N-methylpyridin-3′-yl)porphyrin in solutions

Asymmetrically substituted porphyrin containing a guanine residue at the periphery of the porphyrin cycle was synthesized in an acetic acid medium using the C—H activation method. The quaternization of the product was carried out to prepare water-soluble porphyrin. The structure of the porphyrin was confirmed by electronic absorption spectroscopy, ¹H NMR spectroscopy, and mass spectrometry. According to the results of studying the photochemical properties and complexing ability of the synthesized porphyrin with respect to representative oligonucleotides poly[d(AT)₂] and poly[d(GC)₂] and natural calf thymus DNA, the porphyrin forms intercalation complexes with poly[d(GC)₂] and DNA and binds to poly[d(AT)₂] in the groove. The photoirradiation of the porphyrin complexes with poly[d(AT)₂] leads to the formation of associates, while the photoirradiation of the porphyrin complexes with poly[d(GC)₂] and DNA induces a partial destruction of the nucleic acid.