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Abstract: A simple synthesis of new amphiphilic chlorin derivatives from protoporphyrin-IX dimethyl ester is reported. The preparation of such compounds is based in a straightforward methodology, which involves the Diels–Alder reaction of protoporphyrin-IX dimethyl ester with maleic anhydride followed by addition of nucleophilic species to the initially formed cycloadducts, a transformation, which is highly regioselective. Preliminary photophysical studies with the new compounds show that they meet adequate features for PDT applications. [Copyright &y& Elsevier]

Conjugates based on porphyrin (porph) and rhodamine (rh) moieties linked by amide bonds, dyad 1 (porph-spacer-rh) and triad 2 (porph-spacer-rh-spacer-porph), were prepared respectively from precursor 1 and precursor 2 . The sensing ability of precursor 1 , dyad 1 and triad 2 towards the divalent metal ions Cu 2+ , Zn 2+ , Cd 2+ , Pb 2+ , Hg 2+ and the monovalent Hg + was explored in solution by absorption and fluorescence spectroscopy as well as in gas phase using matrix-assisted laser desorption/ionization (MALDI)-TOF mass spectrometry. In solution one-metal-per-ligand molar ratio was obtained with precursor 1 and triad 2 , however, a two-metal-per-ligand molar ratio was observed with dyad 1 . Additionally, the results obtained by MALDI-TOF-MS confirmed the gas-phase sensing abilities of dyad 1 towards all metal ions tested and of triad 2 towards Zn 2+ . Computational DFT calculations confirm the same stoichiometry. [ABSTRACT FROM AUTHOR]

Highlights: [•] Iron(III) enzymes involved on indigo synthesis were mimicked for dye production. [•] Indole is oxidized by H2O2 in the presence of a Fe(III)porphyrin in ethanol. [•] A simpler and more efficient methodology is obtained relatively to bio-catalysis. [•] The yields of indigo and indolinoid co-products were dependent on the metalloporphyrin system. [•] The results were justified by the formation of different active species. [ABSTRACT FROM AUTHOR]

Highlights: [•] Indole is oxidized by H2O2 in the presence of Mn(III)porphyrins in mild conditions. [•] The biomimetic oxidation of indole can replace biocatalytic and natural processes. [•] Optimization of the reaction allowed the isolation of indigo and indirubin pigments. [•] 2-Oxoindole, isatin, indoxyl and other coupling derivatives were produced. [•] The reaction has relevance for biomedical studies and dye industry. [Copyright &y& Elsevier]

Abstract: New flavonoid–porphyrin conjugates were synthesized using the cross-coupling Buchwald–Hartwig amination for the coupling of flavonoid and porphyrin moieties. A unique di-substituted flavone–porphyrin conjugate was also synthesized under similar reaction conditions for the first time. All the conjugates were fully characterized by NMR spectroscopy. The photophysical properties namely fluorescence and singlet oxygen production were evaluated considering their use for photodynamic therapy applications. [Copyright &y& Elsevier]

Abstract: New porphyrin indolin-2-one conjugates were synthesized via palladium-catalyzed amination reactions of iodinated and dibrominated indolin-2-one derivatives with (2-amino-5,10,15,20-tetraphenylporphyrinato)nickel(II). The combination of palladium catalysts and the phosphine ligand dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos) is an effective methodology for catalyzing the coupling of 5-iodo-, 5,7-dibromo- and 4,6-dibromo-1,3,3-trimethylindolin-2-one with 2-aminoporphyrin to give the corresponding mono-(2-aminoporphyrinyl)- and di-(2-aminoporphyrinyl)-substituted indolin-2-ones in satisfactory yields under mild conditions. The mono brominated porphyrinic derivatives also underwent cross-coupling reactions under similar catalytic conditions. The studies also demonstrated that the course of the coupling process depends on factors, such as the catalytic system, number and position of the halogen substituents and the heating condition. Insights into the reactivity trends of the 5-iodo; 4,6- and 5,7-dibrominated indolin-2-one derivatives was carried out using theoretical calculations performed using density-functional theory with the B3LYP functional. [Copyright &y& Elsevier]

Abstract: 2-Vinyl-5,10,15,20-tetraphenylporphyrinatozinc(II) reacts with nitrile imines, generated in situ from ethyl hydrazono-α-bromoglyoxylates, affording the corresponding pyrazolines in good to excellent yields. Treatment of pyrazoline derivatives with DDQ affords the corresponding pyrazole derivatives with moderate to excellent yields. When the hydrolysis of ester group in the pyrazoline derivatives was considered, it was observed the concomitant oxidation of the heterocyclic unit, which allowed directly obtaining porphyrin-pyrazole derivatives with a carboxylic group, in very good yields. The photophysical properties of the pyrazoline and pyrazole porphyrin derivatives show that the influence of the heterocyclic substituents is limited by the tendency of these molecules to aggregate. All other properties and especially the triplet kinetics remain unaffected. The adducts with low tendency to aggregate showed very high singlet oxygen yield, which makes these compounds interesting for their use as photosensitizers for PDT. [Copyright &y& Elsevier]

Abstract: New porphyrin/4-quinolone conjugates were synthesized from the Suzuki–Miyaura coupling reaction of a β-borylated porphyrin with bromo-4-quinolones containing N-ethyl and N-d-ribofuranosyl substituents. The use of electrospray ionization tandem mass spectrometry showed important information about the fragmentation pathways of the new compounds. It was possible to distinguish between those compounds with the porphyrin moiety linked at the 6-position of the quinolone unit from their 7-substituted isomers. The new compounds showed to be good singlet oxygen generators. [Copyright &y& Elsevier]

Abstract: The catalytic insertion of ethyl diazoacetate into a porphyrin derivative bearing an NH2 substituent, in the presence of a Rh-based catalyst, was investigated. The X-ray analysis of one of the isolated products reveals the formation of a chiral supramolecular system. [Copyright &y& Elsevier]

Abstract: The biomimetic oxidation of caffeine with hydrogen peroxide using metalloporphyrins as catalysts, which are known to be good biomimetic models of cytochrome P450 enzymes, is investigated. The two manganese porphyrins tested, chloro[5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrinato]manganese(III), [Mn(TDCPP)Cl], and chloro [5,10,15,20-tetrakis(pentafluorophenyl)porphyrinato]manganese(III), [Mn(TPFPP)Cl], afford high conversions of caffeine for all substrate/catalyst molar ratios. Selectivity was found to be dependent on the catalyst employed, and a new spiro racemic compound is described and fully characterized in the solid state from X-ray diffraction studies. [Copyright &y& Elsevier]

Abstract: 5,10,15-Tris(pentafluorophenyl)corrole slowly undergoes oligomerization when left in solution at room temperature, under air and ambient light. This transformation was studied in different solvents (chloroform, dichloromethane, and toluene) and the main resulting products were identified as the 3,3′-corrole dimer 2a and the 3,3′,17′,3′′-corrole trimer 3a. [Copyright &y& Elsevier]

Electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (ESI-MS/MS) have been used to differentiate the 2- and 4-methylpyridyl isomers of free-base and metallated cationic β-vinylpyridylporphyrins. The analysis by ESI-MS/MS of the deuterated analogs and semiempirical calculations of structural and electronic parameters were also undertaken. The two free-base isomers are easily differentiated by ESI-MS/MS but the presence of a metallic center renders differentiation of the metallated isomers less effective. The data acquired show that of all the studied compounds, the free-base 2-methylpyridyl isomer, which was operative in the in vitro photoinactivation of Herpes simples virus, has a different gas-phase behavior. Local distortion of the macrocycle due to the presence of the β-vinylpyridyl substituent occurs for all the compounds, but a different electron density distribution can account for the observed gas-phase behavior of this potential virus photoinactivator. [Copyright &y& Elsevier]

Abstract: (2-Amino-5,10,15,20-tetraphenylporphyrinato)nickel(II) reacts with 1,4-benzoquinone, 1,4-naphthoquinone and 2-hydroxy-1,4-naphthoquinone, in the presence of a catalytic amount of sulfuric acid, to afford new porphyrin–quinone dyads and π-extended heterocyclic-fused porphyrin derivatives. [Copyright &y& Elsevier]

Abstract: A simple and efficient procedure for the synthesis of porphyrins bearing 1,3-dicarbonyl moieties at the β-position is described. The new compounds were further functionalized and new derivatives containing an heterocyclic ring, an ethyl acetate residue or a 2-oxopropyl group at the β-position have been obtained. [Copyright &y& Elsevier]

Abstract: Porphyrinic pyridinium ylides react with 1,4-benzoquinone and 1,4-naphthoquinone to afford novel meso-substituted indolizine porphyrins. [Copyright &y& Elsevier]

Abstract: An easy route to cationic β-vinyl substituted meso-tetraphenylporphyrin derivatives is described. Two novel compounds were tested in vitro for their antiviral photoactivity against herpes simplex virus type 1. One of these compounds exhibited a significant activity, reaching 99% of virus inactivation after 15min of photoactivation. [Copyright &y& Elsevier]

Abstract: Several manganese(III) porphyrin complexes were evaluated as catalysts in the oxidation of indane and tetralin with hydrogen peroxide, in the presence of ammonium acetate as a co-catalyst. Catalysis by Mn(III) meso-tetra-2,6-dichlorophenylporphyrins gave rise, in a first stage, to benzylic monooxygenation products (1-alcohols and 1-ketones). However, addition of excess of oxidant gave rise to over-oxidation products and, in certain conditions, hydroxy-keto compounds were selectively obtained. Reactions catalysed by Mn(III) meso-tetra-pentafluorophenylporphyrins showed higher capability to generate dehydrogenated products. As a result, 1H-indene and naphthalene were formed. To understand the reactions’ pathway, the oxidations of 1-indanol, 1-indanone, 2-indanol, 1H-indene, 1-tetralol, 1-tetralone, 1,4-dihydroxytetralin and 4-hydroxy-1-tetralone were also considered with manganese (III) meso-tetra-2,6-dichlorophenylporphyrin chloride, Mn(TDCPP)Cl, as catalyst. [Copyright &y& Elsevier]

Focuses on the application of porphyrins to supramolecular chemistry. Synthesis of beta-substituted meso-tetraphenylporphyrins for dipolar cycloaddition reaction; Demethylation of nickel complexes with a mixture of sulfuric acid; Isolation of quinones on didehydro and tetradehydro adducts.

Abstract: Novel π-extended porphyrins were obtained from the Diels–Alder reaction of meso-tetraarylporphyrins with a pyrazine o-quinodimethane derivative. [Copyright &y& Elsevier]