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The synthesis has been carried out of nickel complexes of oximes of two isomers of meso-formyletioporphyrin-II and their conversion in the heterophase system methylene chloride-water into nickel complexes of tripyrrolylisoxazoles has been studied. The structure of one of them was established by X-ray structural analysis.

The extensive published data on methods for the modification of peripheral substituents in chlorophylls a and b and their various semisynthetic derivatives are classified and analyzed. Special attention is paid to specific transformations arising from the presence of the unique macrocyclic tetrapyrrole fragment. Data on certain main pathways to modification of the exocyclic fragment of chlorophylls are also presented.

Porphyrins and chlorins containing acetylacetone residues in the peripheral substituents [-CH(Me)CHAc2] are converted under alkaline conditions into the corresponding deacetylated compounds with [-CH(Me)CH2Ac] residues. Reduction of the latter as acids using sodium borohydride gives the corresponding alcohols and, after esterification, their acetates with branched peripheral [-CH(Me)CH2CH(OAc)Me] substituents. Porphyrins and chlorins with such substituents in water-soluble form may hold interest as new photosensitizers in photodynamic cancer therapy.

We have obtained various adducts, including homodimers and heterodimers of ethanebisporphyrins and ethanebischlorins containing pyrrole and dipyrrylmethane insertions, by reaction of mesodimethylaminomethylporphyrins and chlorins with α-unsubstituted pyrrole derivatives in the presence of methyl iodide.

Porphyrins which contain 1-hydroxy(alkoxy)ethyl or alkoxymethyl substituents on the periphery of the macrocycle (i.e. formally able to yield “benzyl type” carbocations) react with nucleophiles (4-tert-butylphenol or the β-diketones acetylacetone, benzoylacetone, dibenzoylmethane, or 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione) in the presence of excess zinc acetate. They give high yields of the corresponding addition products, which are the zinc complexes of porphyrins with a 1-(4-tert-butylphenoxy)ethyl substituent or with substituents containing β-diketone residues.

The formation of complexes of β-formyl-heptaethylporphyrin and β-(2-formylvinyl)-heptaethylporphyrin in addition to the expected mesoformylporphyrin was detected when formylating the platinum complex of actaethylporphyrin by the Wilsmeier reaction. A possible mechanism is proposed for the unusual formation of similar compounds.

The mass spectral behavior of 1, 2-di (mesoetioporphyr inyl-1)- and 1, 2-di (mesooctaethylporphyrlnyl) ethanes and ethylenes, their Cu and Ni complexes, as well as Ni Schiff bases of 1, 2-di (mesooctaethylporphyrinyl)ethane complexes, under ionization by electron impact and bombardment by accelerated atoms, was studied. Peaks of molecular ions, for which the basic decomposition pathways were established on the basis of an analysis of the parent and daughter ions, were observed in the electron impact mass spectra of all these compounds.

Diquinone derivatives of hematoporphyrin IX with different structures of the quinone fragments were synthesized by the method of mixed anhydrides. The compounds obtained were investigated by UV, IR, PMR, and fluorescence spectroscopy. Pronounced quenching of the fluorescence of porphyrin in the porphyrin quinones, which depends on the acceptor properties of the quinones and the spatial orientation of the donor and acceptor, was observed.

The synthesis of a diquinone derivative of the amino-containing analog of hematoporphyrin IX, obtained by the sequential modification of the tetramethyl hematoporphyrin IX, was accomplished.

The Cu and Ni complexes of etioporphyrin II were subjected to Vilsmeier formylation, and a steric effect of the peripheral substituants on the direction of electrophilic meso substitution in the porphyrins was observed. The corresponding meso-N,N′-dimethylaminomethyl derivatives, which were separated by thin-layer chromatography (TLC) on silica, gel, were obtained. Their structures were proved by means of the IR, PMR, electronic, and mass spectra.

Nickel complexes of the dimethyl esters of meso-dimethylaminomethyl derivatives of mesoporphyrin-II and mesoporphyrin-IX are synthesized. The structure of the prepared isomeric compounds is determined by analysis of their chromatographic properties, visible spectra, as well as of their PMR spectra using the nuclear Overhauser effect.

The dependence of the chemical shifts of the protons in the PMR spectra of mesodimethylaminomethyl derivatives of etioporphyrin and octaethylporphyrin, as well as the Schiff bases of meso-formylporphyrins, on the concentration of trifluoroacetic acid was studied. The order of protonation of the nitrogen atoms of these compounds was determined. The effect of various solvents and acids on the ratio of the equilibria of proton transfer along the hydrogen bond and dissociation of the H complexes with the formation of solvated ions was examined. The PMR spectra of various salts of the Schiff bases of meso-formylporphyrins were studied.

The structures of the products of the polyformylation of Cu, Ni, and Co complexes of etioporphyrin (EP) as monoformyl-, α,γ-diformyl-, α,β-diformyl-, and α,β,γ-triformyl-EP were established by electronic, IR, and PMR spectroscopy and mass spectrometry. α-Formyl-γ-(N-methylformaldimine)-EP and porphyrins that contain a cyclopentane ring can be formed by alkaline treatment of the Vilsmeier formylation products.

It is shown that α-chloro-γ-formyloctaethylporphyrin and porphyrins that contain a cyclopentane ring are formed along with monoformyloctaethylporphyrin and α,γ-diformyloctaethylporphyrin in the Vilsmeier formylation of the Co complex of octaethylporphyrin. Two crystalline modifications of the Zn complex of octaethylporphyrin were obtained, and their UV and IR spectra were studied.

A method was developed for the preparation, from hemin, of a porphyrin with hydroxypropyl substituents in the 13 and 17 positions of the macroring and a number of its derivatives.

Reduction of the corresponding acyl derivatives by means of sodium borohydride [1, 2] is usually employed to obtain porphyrins with α-hydroxyalkyl substituents.