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The synthesis, chromatographic isolation, and structure elucidation of <i>&#946;</i>,<i>&#946;</i>-substituted isomers of dinitro-5,10,15,20-tetraphenylporphyrin complexes are described. <i>meso</i>-Tetraphenyl-porphyrin chelates (Cu^II, Ni^II, Co^II) upon reaction wit e.g., itric acid (yellow HNO₃, <i>d</i> = 1.52, diluted to 25&#8315;50%) in CHCl₃ formed a mixture of nitro-derivatives with combined yields of <i>ca</i> 80%. This nitration (under optimized conditions: 25&#8315;30% HNO₃, 30&#8315;40 min, r.t.) can be carried out selectively to give mainly <i>&#946;</i>,<i>&#946;</i>-dinitro-compounds in yields of up to 73%. From the above mixtures of five possible regioisomers that can be formed, usually two or three of them were isolated, for which the structures were assigned on the basis of ¹H NMR spectra including COSY and NOESY measure-ments. These types of products are attractive starting materials for synthesis of potential anticancer PDT agents with unique structures, being practically unavailable by any other alternative method.