We employed Circular Dichroism (CD) and UV/Vis-spectrophotometric methods to study the interaction of two Fe-containg cationic porphyrins: meso-tetra (4N-butylpyridyl) porphyrin [FeTButPyP4] and meso-tetra (4N-oxyethylpyridyl) porphyrin [FeTOEtPyP4] with DNA at various ionic strengths. The temperature-dependent absorption titration data were used to determine the binding constants and stoichiom...

New metalloporphyrins bearing one or two aryl-aza-crown ether moieties at meso-positions have been synthesized using a palladium catalyzed amination reaction and fully characterized by spectral techniques. X-Ray structural data have been presented for the zinc and copper complexes of mono-substituted aza-crown ether appended metalloporphyrins. UV-Vis and (1)H NMR spectroscopic studies showed th...

trans-AB(2)C porphyrins with A = C(6)H(4)-COOR, C = C(6)H(4)-NX(2) and B = C(6)H(5) (R = CH(3), H; X = O, H) have been synthesised by a rational high-yield procedure (1a-1d) and their zinc(ii) and copper(ii) complexes have been prepared (2a-2d, 3a-3d ).1a, 2a .THF and 3a display different distortions of the porphyrin core as shown by single crystal X-ray crystallography and NSD analyses. The So...

Two-electron oxidation of cobaltous octaethylporphyrin [Co(II)(Et)(8)P] yields a stable pi-cation radical [Co(III)(Et)(8)P](2+.), the optical spectrum of which exhibits spectral changes dependent upon the nature of the counterion. Comparison of these spectra with those of Compounds I of horseradish peroxidase and catalase leads us to propose that these Compounds I contain a pi-cation radical of...

Monolayer arrays of a series of meso-tetra-substituted porphyrins containing octadecyloxy and carboxyl (or pyridyl) groups were prepared on the highly oriented pyrolytic graphite surface at the liquid/solid interface. It was found by means of scanning tunneling microscopy that some porphyrins from this family assemble into various patterns. Specifically, slightly undulated rows are obtained fro...

Porphyrins provide an excellent material for chemical sensors, and they have been used for sensing species both in air and solution. In the gas phase, the broad selectivity of porphyrins is largely dependant on molecular features, such as the metal ion complexed at the core of the aromatic ring and the peripheral substituents. Although these features have been largely exploited to design gas se...

In this paper we review recent advances in computational chemistry and specifically focus on the chemical description of heme proteins and synthetic porphyrins that act as both mimics of natural processes and technological uses. These are challenging biochemical systems involved in electron transfer as well as biocatalysis processes. In recent years computational tools have improved considerabl...

The influence of skin permeation enhancers, such as dimethyl sulphoxide (DMSO) and 1-[2-(decylthio)ethyl]azacyclopentan-2-one (HPE-101), Labrafac CC, Labrafil, Labrasol and Transcutol in a concentration of 10% (wt./wt.) on the formation of porphyrins in normal mouse skin from topical application of creams with methyl 5-aminolevulinate (MAL) was studied. The concentration of porphyrins in the mo...

In addition to the bile pigments, there are present in the urine and stool another series of pyrrole pigments, the porphyrins. Hemoglobin, myoglobin, and other respiratory pigments contain as their prosthetic group a porphyrin of Type III configuration. The porphyrin excreted in urine and feces by normal individuals, and in most pathological states, is coproporphyrin Type I. This substance cann...