71188-40-4

Upstream product

• 872-85-5 pyridine-4-carbaldehyde 
• 109-97-7 pyrrole 
• 100-52-7 benzaldehyde 

Downstream Products

• 127800-97-9 5,10,15-tris(4-pyridyl)-20-(4-aminophenyl)porphyrin 

Relevant academic research and scientific papers

Photodynamic effect of meso-(aryl)porphyrins and meso-(1-methyl-4-pyridinium)porphyrins on HaCaT keratinocytes

Sixteen porphyrins, including neutral, anionic and cationic meso-(aryl)porphyrins and meso-(1-methyl-4-pyridinium)porphyrins were herein evaluated in terms of their photosensitizing properties against HaCaT keratinocytes. After an initial screening, the cationic porphyrins were studied in more details, by both determining their log POWand performing PDT assays in lower porphyrin concentrations. Porphyrins presenting two or more adjacent positively charged groups, directly linked to the macrocycle meso positions, appeared to be the most effective photosensitizers. The present study also included the dicationic 5,10-diphenyl-15,20-di(1-methylpyridinium-4-yl)porphyrin (14b), which has previously shown promising results on a psoriasis-like in vivo model. Overall results indicated that the beneficial effect related to porphyrins on psoriasis can be related to the decreasing of keratinocyte viability. Furthermore, some of the cationic porphyrins studied appeared as candidates to be utilized as photosensitizers for psoriasis treatment.

Regioselective reduction of 5-aryl-10,15,20-tris(pyridyl) porphyrin to 5-aryl-10,15,20-tris(pyridyl)dihydroporphyrin (chlorin)

Dihydroporphyrins or chlorins differ from porphyrins only by saturation of a peripheral double bond of the macrocycle. However, this small structural difference leads to a significant increase of the absorption band at approximately 650 nm, which makes them very interesting candidates for photodynamic therapy applications. The reduction of porphyrins bearing two, three or four pyridyl substituents with tin(II) chloride has been developed for the synthesis of dihydroporphyrins in yields of 15-73%. The reduction of 5-(aryl)-10,15,20-tris(2 or 4-pyridyl)porphyrin with tin(II) chloride dihydrate demonstrated good regioselectivity. Porphyrins with one meso-aryl bearing one electron-donating group (EDG) gave 5-aryl-10,15,20-tris(2-or 4-pyridyl)-17,18-dihydroporphyrins in 17-72% yield. Porphyrins with one meso-aryl bearing one or more electron-withdrawing groups (EWG) gave 5-aryl-10,15,20-tris(4-pyridyl)-17,18-dihydroporphyrins or 5-aryl-10,15,20-tris(4-pyridyl)-7,8-dihydroporphyrins in 15-21% yield and isobacteriochlorin. We have also proven the possibility of functionalizing these compounds to design new regioisomerically pure photosensitizers.

Molecular Imprinting Inside Dendrimers

Synthetic hosts capable of binding porphyrins have been produced by a mixed-covalent-noncovalent imprinting process wherein a single binding site is created within cross-linked dendrimers. Two synthetic hosts were prepared, using as templates 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin and 5,10,15,20-tetrakis(3,5-dihydroxyphenyl)porphyrin. These two templates were esterified with, respectively, fourth- and third-generation Frechet-type dendrons containing homoallyl end-groups. The resulting tetra-and octadendron macromolecules underwent the ring-closing metathesis reaction using Grubbs' Type I catalyst, RuCl2(P(C6H5) 3)2(CHCH2C6H5), to give extensive interdendron cross-linking. Hydrolytic removal of the porphyrin cores afforded imprinted hosts whose ability to bind porphyrins with various peripheral substituents was investigated by UV-visible spectrophotometric titrations and size exclusion chromatography. The results indicate a high yield of imprinted sites that show high selectivity for binding of porphyrins capable of making at least four hydrogen bonds, but only a moderate degree of shape selectivity.

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

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. 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.