- Functionalization of Deutero- and Protoporphyrin IX Dimethyl Esters via Palladium-Catalyzed Coupling Reactions
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Herein, we report the functionalization of the β-positions of deutero- and protoporphyrin IX dimethyl esters. Initial halogenations were carried out on both deutero- and protoporphyrin IX dimethyl esters. Although previously reported, vastly optimized yields with respect to deuteroporphyrin halogenation were obtained. Methods were developed for the bromination of the vinyl groups of protoporphyin IX dimethyl ester. Subsequent palladium-catalyzed coupling reactions were utilized to modify the periphery of these naturally occurring porphyrin derivatives with a variety of functionalities. The described Suzuki, Sonogashira, and "Click" reactions demonstrate the ease at which these porphyrins may be manipulated and even interchangeable, as will be discussed for one example. X-ray crystallographic analysis successfully determined the structure of two derivatives synthesized. Results identified a unique head-to-tail stacking pattern for 3,8-diphenyldeuteroporphyrin IX dimethyl ester, most likely due to the presence of additional aromatic moieties on the periphery of the porphyrin.
- O'Brien, Jessica M.,Sitte, Elisabeth,Flanagan, Keith J.,Kühner, Hannes,Hallen, Lukas J.,Gibbons, Dáire,Senge, Mathias O.
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- NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY OF PETROPORPHYRINS Self-Aggregation Effects, Nuclear Overhauser Enhancements, and Spin-Lattice Relaxation used in Structural Elucidation
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The substitution pattern of the two major petroporphyrins of Marl Slate, the ETIO III and the C32 DPEP, is determined by NMR spectroscopy alone, using self-aggregation effects, nuclear Overhauser enhancements and spin-lattice relaxation times.Protoporphyrin IX dimethyl ester was used as a model compound.
- Krane, Jostein,Skjetne, Tore,Telnaes, Nils,Bjoroy, Malvin,Solli, Hauk
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- Synthesis and biological evaluation of thioglycosylated porphyrins for an application in photodynamic therapy
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The aim of this work is the synthesis of a new family of glycosylated poryphrins in which the sugar moieties are linked to the tetrapyrrole ring by a thioglycosidic bond. Two series have been designed. The first one corresponds to meso-aryl porphyrin derivatives. The second one has been obtained from protoporphyrin IX derivatization. Aryl-porphyrins were prepared from tristolyl o- and p-hydroxyporphyrins followed by bromoallylation and thioglycosylation with peracetylated S-glucose, mannose and galactose and deprotection. The other series has been synthesized from protoporphyrin IX dimethylester with a regioselective glycosylation of terminal alkenyl carbon. The UV-visible, NMR and MALDI mass spectra are presented. Photocytotoxicities of the synthesized compounds against K562 chronic leukaemia cell line has been evaluated. Synthesis and biological evaluation of the following porphyrins. Copyright
- Sylvain,Zerrouki,Granet,Huang,Lagorce,Guilloton,Blais,Krausz
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- Microwave-Assisted Synthesis of α-Amino Phosphonates Derived from Formylporphyrins of Natural Origin
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The first synthesis of α-amino phosphonates comprising porphyrin core was accomplished. Three methods of obtaining α-amino phosphonates 5-8 were compared. Conventional heating of formylporphyrins 1-4 with r-BuNH 2 and (EtO)2P(O)H in
- Pavlov, Vsevolod Yu.,Kabachnik, Maria M.,Zobnina, Elena V.,Timofeev, Vladimir P.,Konstantinov, Igor O.,Kimel, Boris G.,Ponomarev, Gelii V.,Beletskaya, Irina P.
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- Albumin aggregation promoted by protoporphyrin in vitro
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Protoporphyrin upon its binding with serum albumin changes its secondary structure due to the conversion of part of α helices into β-folding. This process results in the association of albumin globules in vitro.
- Gubarev, Yury A.,Kiselev, Aleksey N.,Lebedeva, Natalya Sh.,Syrbu, Sergey A.,Yurina, Elena S.
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- Photophysical properties of porphyrin derivatives: Influence of the alkyl chains in homogeneous and micro-heterogeneous systems
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This work is focused on the evaluation of the photophysical properties of protoporphyrin-IX derivatives with different alkyl chains. The goal of this work is to understand the physicochemical properties and select prototypes of photosensitizers for photodynamic therapy. Solvents with different dielectric constants were used to obtain relevant data on different physical and chemical processes, such as fluorescence quantum yield and emission level of aggregation in nonpolar media. In addition, studies were conducted in micro-heterogeneous systems through the interaction of porphyrin derivatives with different surfactants, such as cetyltrimethylammonium bromide, sodium dodecyl sulfate and octyl phenol ethoxylate. The compounds were characterized by electronic absorption spectroscopy in the ultraviolet-visible region and fluorescence emission spectroscopy. The comparative study between the different chemical environments evaluated in the present study represents a relevant contribution to the comprehension of the properties acquired by the porphyrins in different micro-heterogeneous systems, which allows us to understand various interactions that these compounds are subject in biological medium, such as the influence of the polarity of the medium in the reactivity of porphyrins with nonpolar substituents. These results show the decisive physicochemical influence of the alkyl chains on the properties of the tetraazomacrocycle porphyrin.
- Santos, Sandra Cruz Dos,Moreira, Leonardo Marmo,Novo, Diogo La Rosa,Santin, Luiza Rosimeri Romano,Bianchini, Daniela,Bonacin, Juliano Alves,Romani, Ana Paula,Fernandes, Adjaci Uchoa,Baptista, Mauricio S.,De Oliveira, Hueder Paulo Moises
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- Light harvesting in silicon(111) surfaces using covalently attached protoporphyrin IX dyes
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We report the photosensitization of crystalline silicon via energy transfer using covalently attached protoporphyrin IX (PpIX) derivative molecules at different distances via changing the diol linker to the surface. The diol linker molecule chain length was varied from 2 carbon to 10 carbon lengths in order to change the distance of PpIX to the Si(111) surface between 6 ? and 18 ?. Fluorescence quenching as a function of the PpIX-Si surface distance showed a decrease in the fluorescence lifetime by almost two orders of magnitude at the closest separation. The experimental fluorescence lifetimes are explained theoretically by a classical Chance-Prock-Silbey model. At a separation below 2 nm, we observe for the first time, a F?rster-like dipole-dipole energy transfer with a characteristic distance of R0 = 2.7 nm.
- Alderman, Nicholas,Danos, Lefteris,Fang, Liping,Grossel, Martin C.,Markvart, Tom
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- Syntheses, stability, and tumorcidal activity of porphyrin dimers and trimers with ether linkages
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The first syntheses of a series of regiochemically pure porphyrin dimers and trimers with ether linkages which are structurally related to Photofrin-II are described. Stability of these oligomers was investigated using variable temperature proton NMR spectroscopy, and preliminary biological results reveal that manupulation of peripheral substituents causes a remarkable difference in photosensitizing ability in vivo.
- Pandey, Ravindra K.,Shiau, Fuu-Yau,Medforth, Craig J.,Dougherty, Thomas J.,Smith, Kevin M.
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- Induction of aminolevulinic acid synthase gene expression and enhancement of metabolite, protoporphyrin IX, excretion by organic germanium
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Poly-trans-[(2-carboxyethyl) germasesquioxane], Ge-132 is a water-soluble organic germanium compound. Oral intake of dietary Ge-132 changes fecal color and we attempted to identify the fecal red pigment, which increased by the intake of dietary Ge-132. Sprague Dawley rats were given diets containing Ge-132 from 0 to 0.5% concentration. Fecal red pigment was extracted and purified for optical and structural studies. We examined the fecal red pigment content by high performance liquid chromatography (HPLC), and hepatic gene expressions relating to heme synthesis by reverse transcription polymerase chain reaction (RT-PCR). The purified red pigment had particular optical characteristics on the ultraviolet (UV)-visible spectrum (Soret band absorbance at 400 nm) and fluorescence emission at 600 nm by 400 nm excitation, and was identified as protoporphyrin IX by LC-MS analysis. Protoporphyrin IX significantly (P 0.05) increased 2.4-fold in the feces by the intake of a 0.5% Ge-132 diet. Gene expression analysis of the liver explained the increase of protoporphyrin IX by dietary Ge-132 as it enhanced (P 0.05) aminolevulinic acid synthase 1 (Alas1), a rate-limiting enzyme of heme synthesis, expression 1.8-fold, but decreased ferrochelatase (Fech) expression 0.6-fold (P 0.05). The results show that the intake of dietary Ge-132 is related to heme metabolism. Because protoporphyrin IX is used to treat chronic hepatitis, Ge-132 may be a beneficial substance to increase protoporphyrin IX in the liver.
- Nakamura, Takashi,Saito, Miki,Shimada, Yasuhiro,Fukaya, Haruhiko,Shida, Yasuo,Tokuji, Yoshihiko
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- Synthesis of protoporphyrin-lipids and biological evaluation of micelles and liposomes
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Protoporphyrin IX (PPIX) lipids were synthesized by introducing a long alkyl chain, such as C13, C15, and C17, at each vinyl group on PPIX via hydrobromination. The PPIX lipids exhibited a water-soluble property by forming their micelles in water and the PPIX-lipid micelles showed relatively low cytotoxicity toward HeLa cells (IC50 = 151.7-379.9 μM) without light irradiation. PL-C17 liposomes (post-inserted liposomes) were readily prepared by adding PL-C17 micelle solution to the liposome solution. The IC 50 values of PPIX, PL-C17 micelles, and PL-C17 liposomes toward HeLa cells were 0.53, 5.65, and 12.9 μM, respectively, after irradiation with a xenon lamp in the 400-800 nm range for 2 min. PL-C17 liposomes were selectively accumulated in the Golgi apparatus in cells.
- Tachikawa, Shoji,El-Zaria, Mohamed E.,Inomata, Ryu,Sato, Shinichi,Nakamura, Hiroyuki
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- Boron-containing protoporphyrin ix derivatives and their modification for boron neutron capture therapy: Synthesis, characterization, and comparative in vitro toxicity evaluation
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A novel series of boronated porphyrins for potential use in boron neutron capture therapy (BNCT) and photodynamic therapy (PDT) for tumor suppression is described. Protoporphyrin IX {i.e., bis(α-methyl-β-pen-tylethylether)protoporphyrin IX, and bis(α-methyl-β-dodecanylethylether)protoporphyrin IX} bearing polyhedral borane anions (B12H11SH2-, B12H11NH3-, or B12H11OH2-) were synthesized with reasonable yields. Modification of the protoporphyrin IX structure was achieved by variation of the lengths of the alkyl chains (pentyl and dodecanyl) attached through ether linkages to the former vinyl groups. The goal of this modification was to develop boronated porphyrins with chemical and physical properties that differed from those of protoporphyrin IX. Performance of an MTT assay with each derivative revealed that the synthesized boronated porphyrins showed low cytotoxicities in a variety of cancer cells. Of these compounds, B12H11NH22--conjugated porphyrin induced a significant increase in the level of boron accumulation and PDT efficacy against HeLa cells.
- El-Zaria, Mohamed E.,Ban, Hyun Seung,Nakamura, Hiroyuki
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- The identification of a carbon linked oligomer in hematoporphyrin derivative and Photofrin II
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The presence of carbon linked oligomeric porphyrins in hematoporphyrin derivative and Photofrin II has been established by FAB mass spectrometry and hydrolysis studies. A dimer derived from this material has been isolated and characterized by nmr spectroscopy and mass spectrometry.
- Byrne,Ward
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- Development of the sensitizer for generating higher-energy photons under diluted condition via the triplet-triplet annihilation-supported upconversion
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It was previously reported that photon upconversion can occur in the solution containing anthracene and the Pt complex of octaethylporphyrin (PtOEP) via the triplet-triplet annihilation process. In this study, by employing the modified Pt complex of the dual anthracene-tethered porphyrin, DA-PtP as a sensitizer, it is demonstrated that shorter-wavelength light can be generated under diluted condition. We synthesized DA-PtP and compared upconversion properties by changing the type of sensitizers. Accordingly, it was shown that the photon upconversion proceeded with the xenon lamp (540 nm) in the presence of DA-PtP. Furthermore, it was found that the emission band in the shorter wavelength light in the near UV region was observed from the solution containing DA-PtP even under diluted condition. From the mechanistic investigation, it was proposed that the anthracene moieties in DA-PtP might inhibit to form agglomeration with the free anthracene. As a result, reabsorption of the higher-energy light generated from upconversion could be suppressed.
- Tanaka, Kazuo,Ohashi, Wataru,Inafuku, Kenichi,Shiotsu, Shohei,Chujo, Yoshiki
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- Preparation method of protoporphyrin disodium
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The invention provides a preparation method of protoporphyrin disodium, and belongs to the field of synthesis of organic compounds. The method comprises the following steps: ensuring that protoporphyrin, absolute methanol and concentrated sulfuric acid are subjected to alcohol acid reaction in an ultrasound condition, so as to obtain protoporphyrin diester; ensuring that the protoporphyrin diester, a NaOH methanol solution and methylbenzene are subjected to saponification reaction in an ultrasound condition, so as to obtain the protoporphyrin disodium. The method has the advantages that assistance of ultrasonic wave is adopted to replace high-temperature reflux, so as to form the protoporphyrin disodium, hydrogen chloride gas is not required to be prepared during preparation, the adoptionof strong-toxicity reagents, such as chloroform, is further avoided, a high-temperature condition is not required to be use, the technology is simplified, and the whole process is easy to operate.
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Paragraph 0063-0082
(2018/11/22)
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- Facile iodination of the vinyl groups in protoporphyrin IX dimethyl ester and subsequent transformation of the iodinated moieties
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Iodination of protoporphyrin IX dimethyl ester using phenyliodine bis(trifluoroacetate) (PIFA) and I2 was studied. Iodine added to both the C3- and C8-vinyl groups equally to afford the iodohydrin or iodoether in the presence of water or alcohol, respectively. Any meso-hydrogen atom was not substituted by an iodine atom under these conditions, although both the vinyl group and one of the meso positions of methyl pyropheophorbide-a bearing a chlorin π-system, a chlorophyll-a derivative, was modified with PIFA and I2. The reaction intermediates derived from the porphyrin were more reactive than those from the chlorin and liable to form intermolecular linkages. The obtained 2-iodo-1-hydroxyethyl group was transformed into a formyl group by a mild treatment. The corresponding iodoether moiety was readily converted into the acetyl group under basic conditions. These transformations were also applicable to smaller olefins such as styrene.
- Miyata, Kota,Yasuda, Satoru,Masuya, Takuto,Ito, Satoshi,Kinoshita, Yusuke,Tamiaki, Hitoshi,Oba, Toru
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supporting information
p. 3707 - 3711
(2018/05/28)
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- Chlorin derivatives sterically-prevented from self-aggregation with high antitumor activity for photodynamic therapy
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In this study two new chlorin derivatives sterically prevented from aggregation were synthesised by the Diels-Alder reaction between protoporphyrin IX dimethyl ester and 1-(2-hydroxyethyl)maleimide. The compounds were fully characterised by 1H NMR, 13C NMR, UV-Vis and high-resolution mass spectroscopy (HRMS) and their photochemical properties such as singlet oxygen quantum yield (?0), fluorescence quantum yield (?f) and photodegradation were also evaluated. Furthermore, the partition coefficient (log P) revealed that these compounds present amphiphilic properties. Studies of the photodynamic action in tumour cells (HEp-2 and HeLa) and non-tumour cells (Vero) were also performed in order to confirm the photodynamic therapy (PDT) activity that was indicated by the preliminary photophysical studies. Those phototoxicity results were 55–77% higher than the results obtained with the commercial photosensitiser verteporfin. Finally, cytotoxic assays were performed with the new photosensitiser candidates and cell death was determined using fluorescence microscopy, which provided information about the mechanisms of cell death. In general, we have obtained improved and accessible compounds for PDT studies, as highlighted by the research presented here.
- Linares, Irwin A.P.,de Oliveira, Kleber T.,Perussi, Janice Rodrigues
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p. 518 - 527
(2017/06/29)
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- Protonation-deprotonation equilibria in tetrapyrroles Part 4: Mono- and diprotonations of deutero-, hemato-, meso-, and protoporphyrin IX dimethyl esters in methanolic hydrochloric acid
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The N-protonations in the deutero, hemato, meso and protoporphyrin IX dimethyl esters (DME) were investigated by spectrophotometric titrations using HCl as the acid and methanol as the solvent. Two spectroscopically different protonated species were observed for each porphyrin DME in addition to the neutral form. These were assigned to the N-protonated monocation and dication. There were no difficulties encountered in observing the monocation formation in the HCl-MeOH system. Very sharp isosbestic points were characteristic of each protonation stage. The pK3 values for the porphyrins in the above order were 3.23, 4.70, 2.93 and 3.37; the pK4 values were 2.48, 2.62, 2.41 and 2.64, respectively. For all porphyrins studied, no further spectral changes were observed after the dication was completely formed. This was interpreted as indicating that the formation of more highly protonated species is not possible in fullydelocalized porphyrins possessing the 18 π-electron [18]diazaannulene delocalization pathway. When the titration was performed on the free dicarboxylic acid porphyrins, aggregation obscured the first protonation step and no clear monocation spectrum could be distinguished. However, also in that case the titration ended up to a UVvis spectrum typical of the dication and the effect of aggregation on the pK4 values was negligible. The UVvis spectrometric parameters are given for the neutral forms and for the protonated species of the porphyrin DMEs. The results are discussed in terms of the NH tautomerization connected to the π-electron delocalization pathway (aromaticity), which tends to hinder outofplane distortions in the porphyrin plane, and in terms of solvation and counterion stabilization of the protonated forms.
- Hynninen, Paavo H.
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p. 385 - 395
(2015/05/20)
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- Synthesis of functionalized chlorins sterically-prevented from self-aggregation
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The synthesis of six new regioisomeric chlorin derivatives sterically-prevented from self-aggregation is described. The compounds were prepared by the Diels-Alder reaction between protoporphyrin IX dimethyl ester, and N-[p-(1,3-dithiolan)phenyl]maleimide and N-(p-formylphenyl)maleimide. The protopophyrin IX dimethyl ester was synthesized in 2 steps from natural hematoporphyrin using a modified procedure from literature, and the substituted maleimides were conveniently synthesized, aiming at producing formyl-chlorins for subsequent functionalization with amphiphilic groups. The Diels-Alder reactions were systematically studied in order to establish optimized conditions for the cycloadditions. The regioisomers were fully characterized and the aggregation studies were performed by NMR, UV-Vis spectroscopy, and also HRMS (ESI-TOF and MALDI-TOF). Preliminary evaluations on the photosensitizing activities and amphiphilicity were carried out indicating that these new compounds are potential candidates, to be studied in more advanced tests of Photodynamic Therapy (PDT). This work represents on advance on our previous study, with respect to these new structures, their photophysical properties and amphiphilicity.
- Dos Santos, Fabiane A.B.,Uchoa, Adjaci F.,Baptista, Mauricio S.,Iamamoto, Yassuko,Serra, Osvaldo A.,Brocksom, Timothy J.,De Oliveira, Kleber T.
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p. 402 - 411
(2013/10/08)
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- A convenient hydrogenation method for the synthesis of metallo- mesoporphyrin IX dimethyl esters via self-catalyzed CoCl2-NaBh 4 reagent system
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A convenient protocol has been developed for the hydrogenation of metallo-protoporphyrin IX dimethyl esters (MPPDMEs) to their mesoporphyrin analogues using CoCl2-NaBH4 reagent system. Metallo-porphyrin complexes were found to perform as self-catalysts in this procedure. This method provides several advantages such as safe and simple procedure, short reaction time, high yields and low cost. Copyright
- Xu, Shichao,Hu, Bingcheng,Hu, Tianjing,Wang, Huan,Huang, Xiuyou,Lou, Xingkun,Liu, Zuliang
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p. 2461 - 2465
(2013/01/15)
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- Process For Preparing Porphyrin Derivatives, Such As Protoporphyrin (IX) And Synthesis Intermediates
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The present invention relates to a process for preparing a porphyrin of formula (I), optionally in the form of a salt with an alkali metal and/or in the form of a metal complex: in which: R and R′ are as defined in claim 1, comprising: a step of condensation, in an acidic medium, between a dipyrromethane of formula (II): in which R′b is as defined above for (I), and a dipyrromethane of formula (III): in which R″ is as defined in claim 1, and also the compounds of formula (III).
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Page/Page column 20-21
(2008/12/07)
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- New Syntheses and Reactions of Some Halogenated Porphyrins
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Efficient syntheses of 2,4-dibromo- and 2,4-diiododeuteroporphyrin IX have been carried out by treating zinc(II) 2,4-bis(chloromercurio)deuteroporphyrin IX dimethyl ester (2) with bromine or iodine.Unavoidable mesochlorination occurs when 2 is treated with chlorine and with other free-radical chlorinating agents.Regioselective meso-chlorination and peripheral (β) bromination are shown to occur from brief treatment of copper(II) deuteroperphyrin IX or β-unsubstituted a,c-biladienes with the corresponding copper(II) halide in refluxing dimethylformamide.Protoporphyrin IX has been synthesized by vinylation of 2 via ethylene/LiPdCl3 (35percent yield), with vinyl bromide and Wilkinson's catalyst (63percent), or from 2,4-dibromodeuteroporphyrin IX with ethenyltributylstannane/(Ph3P)4Pd0 (85percent).
- Minnetian, Ohannes M.,Morris, Ian K.,Snow, Kevin M.,Smith, Kevin M.
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p. 5567 - 5574
(2007/10/02)
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- A FACILE PORPHYRIN ESTERIFICATION / ETHERIFICATION PROCEDURE
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Porphyrin carboxylic acids and 1-hydroxyethyl groups can be rapidly esterified and etherified using alcohol/trialkyl orthoformate/strong acid mixtures; addition of water to the reagent permits esterification only.
- Byrne, Christopher J.,Ward, A. David
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p. 1421 - 1424
(2007/10/02)
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- SYNTHESES OF HEMATOPORPHYRIN DIMERS AND TRIMERS WITH ETHER LINKAGES
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In order to aid in elucidation of the structure of the active components in hematoporphyrin derivative (Hpd), the first syntheses of an ether-linked hematoporphyrin dimer (6) and trimer (12) are described.After hydrolysis, these compounds were positively identified, by comparative HPLC, as components in Photofrin-II.
- Pandey, Ravindra K.,Dougherty, Thomas J.,Smith, Kevin M.
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p. 4657 - 4660
(2007/10/02)
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- Biosynthesis of Porphyrins and Related Macrocycles. Part 25. Synthesis of Analogues of Coproporphyrinogen-III and Studies of their Interaction with Copropophyrinogen-III Oxidase from Euglena gracilis
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Analogues of coproporphyrinogen-III have been synthesized in which the propionate groups respectively on ring-A and on ring-B are modified either by homologation or esterification.Coproporphyrinogen-III oxidase from Euglena gracilis acts on the analogues which possess normal substituents on ring-A to generate a vinyl group on that ring.The enzyme does not affect the analogues in which the ring-A propionate group has been changed.Conditions have been defined for the MacDonald synthesis of porphyrins which yield products of high isomeric purity.
- Robinson, John A.,McDonald, Edward,Battersby, Alan R.
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p. 1699 - 1710
(2007/10/02)
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- New Efficient Total Syntheses of Derivatives of Protoporphyrin-IX Bearing Deuterated Methyl Groups
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New total syntheses of hemins which are regioselectively deuterated in the 1,5 (2), 5 (3) or 8 (4) methyl groups are described.Syntheses of hemins 2 and 3 follow the progression from pyrromethane 12 to t-butyl tripyrrene-carboxylate hydrobromide (17 and 30) and then to a,c-biladiene dihydrobromide (19 and 31), but for reasons of economy in use of labeled monopyrroles, the a,c-biladiene dihydrobromide 40 for hemin 4 is approached in an initially "clockwise" manner by synthesis of a benzyl tripyrrene-carboxylate hydrobromide 37 from the pyrromethane 5.Cyclization of the a,c-biladienes (19, 31, and 40) was accomplished by brief heating in dimethylformamide in the presence of copper(II) chloride.
- Smith, Kevin M.,Pandey, Ravindra K.
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p. 1383 - 1388
(2007/10/02)
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- Mercuration Reactions of Porphyrins: New Efficient Syntheses of Harderoporphyrin and Isoharderoporphyrin
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Treatment with mercury(II) acetate of metal complexes of porphyrins bearing peripherally unsubstituted positions gives the corresponding mercurated derivatives; using the palladium-olefin reaction, this observation is exploited in the synthesis of coproporphyrin III tetramethyl ester (2), harderoporphyrin trimethyl ester (3), and isoharderoporphyrin trimethyl ester (4).
- Smith, Kevin M.,Langry, Kevin C.
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p. 217 - 218
(2007/10/02)
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- Biosynthesis of Porphyrins and Related Macrocycles. Part 13. Structure of the Protoporphyrin Isomer derived from Coproporphyrinogen lV by the Action of Beef-Liver Coproporphyrinogenase: Synthesis of Protoporphyrin Xlll
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Coproporphyrinogen lV (8) is synthesised and is oxidatively decarboxylated by coproporphyrinogenase from beef-liver to produce, after aromatisation, a porphyrin proved to be protoporphyrin Xlll (11) by spectroscopy and by unambiquous synthesis; the synthesis route is described.A monovinylporphyrin, derived from an intermediate for the conversion (8) -> (11), is also isolated.The importance of these results for earlier biosynthetic studies with pyrromethanes is discussed.
- Battersby, Alan R.,Hamilton, Andrew D.,McDonald, Edward,Mombelli, Luisa,Wong, Oi-Hoong
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p. 1283 - 1289
(2007/10/02)
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- The Chemistry of Pyrrolic Compounds. XLV. Haematoporphyrin Derivative: Haematoporphyrin Diacetate as the Main Product of the Reaction of Haematoporphyrin with a Mixture of Acetic and Sulfuric Acids
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A mixture of acetic and sulfuric acids converts haematoporphyrin into a complex mixture of porphyrins of which the main product has been characterized as the diacetate (1g).Other compounds identified in the reaction mixture were the known vinylporphyrins (1b-d), (1h) and (1i) and the isomeric monoacetoxyethyl(monohydroxyethyl)porphyrins (1l) and (1m).Analysis of the reaction mixture was complicated by the presence of 1'-ethoxyethyl derivatives (1e) or (1f), (1j) and (1k) which presumably arose by solvolysis of the corresponding acetate with ethanol present in the chloroform used for the the chromatographic separation.
- Clezy, Peter S.,Hai, Ton That,Henderson, Robert W.,Thuc, Le van
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p. 585 - 597
(2007/10/02)
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