Porphyrin chemistry pertaining to the design of anti-cancer drugs; part 1, the synthesis of porphyrins containing meso-pyridyl and meso-substituted phenyl functional groups

Abstract

Condensation of pyrrole with a benzaldehyde and 4-pyridinecarboxaldehyde mixture yields the six possible meso-substituted phenyl or pyridyl porphyrins. Nitration of four of these has yielded 13 other porphyrins containing one to four 4-nitrophenyl moieties, and SnCl2 reduction of eight of these nitrophenylporphyrins gives the corresponding 4-aminophenyl(phenyl)- or 4-aminophenyl(phenyl)(4-pyridyl)-porphyrins. Twelve of the porphyrins are new, but all 27 are fully characterized by 1H NMR; resonances for every proton within each of the phenyl, pyridyl, and pyrrole rings are assigned. Trends in UV–VIS data are discussed, while IR and mass spectral data are noted for selected porphyrins.