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Artículos de revistas sobre el tema "Pyrrole"

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Autor: Grafiati

Publicado: 4 de junio de 2021

Última modificación: 10 de marzo de 2023

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1

Mohamed, Mosaad, Ramdan El-Domany y Rania Abd El-Hameed. "Synthesis of certain pyrrole derivatives as antimicro-bial agents". Acta Pharmaceutica 59, n.º 2 (1 de junio de 2009): 145–58. http://dx.doi.org/10.2478/v10007-009-0016-9.

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Synthesis of certain pyrrole derivatives as antimicro-bial agentsIn an effort to establish new pyrroles and pyrrolo[2,3-d] pyrimidines with improved antimicrobial activity we report here the synthesis andin vitromicrobiological evaluation of a series of pyrrole derivatives. A series of new 2-aminopyrrole-3-carbonitriles (1a-d) were synthesized from the reaction of benzoin, primary aromatic amines and malononitrile, from which a number of pyrrole derivatives (2a-dto5a-d) and pyrrolo[2,3-d]pyrimidines (6a-dto10a, d) were synthesized. Thein vitroantimicrobial testing of the synthesized compounds was carried out against Gram-positive, Gram-negative bacteria and fungi. Some of the prepared compounds, [2-amino-1-(2-methylphenyl)-4,5-diphenyl-1H-pyrrole-3-carbonitriles (1b), 2-amino-3-carbamoyl-1-(3-methylphenyl)-4,5-diphenyl-1H-pyrroles (2b),N-(3-cyano-1-(2-methylphenyl)-4,5-diphenyl-1H-pyrrol-2-yl)-acetamides (3b),N-(3-cyano-1-(3-methylphenyl)-4,5-diphenyl-1H-pyrrol-2-yl)-acetamides (3c), 2-amino-1-(4-methoxyphenyl)-4,5-diphenyl-3-tetrazolo-1H-pyrroles (5d),7-(4-methoxyphenyl)-5,6-diphenyl-7H-pyrrolo [2,3-d]pyrimidin-4(3H)-ones (7d), 7-(3-methylphenyl)-5,6-diphenyl-7H-pyrrolo[2,3-d]pyrimidin-4(3H)-thione (9b) andN-(7-(2-methylphenyl)-5,6-diphenyl-7H-pyrrolo[2,3-d] pyrimidine)-N-aryl amines (10a)] showed potent antimicrobial activity.

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2

Ta, Daniel D., Jeanne M. Favret y Sergei V. Dzyuba. "Facile Synthesis of Pyrrolyl-Containing Semisquaraines in Water as Precursors for Non-Symmetric Squaraines". Compounds 3, n.º 1 (28 de diciembre de 2022): 17–26. http://dx.doi.org/10.3390/compounds3010002.

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One-step reactions between squaric acid and pyrroles, such as 3-ethyl-2,4-dimethyl-pyrrole and 1,2,5-trimethylpyrrole, in water provide the corresponding pyrrol-2-yl- and pyrrol-3-yl-containing semisquaraines in high yields. These semisquaraines serve as useful precursors for the synthesis of various non-symmetric pyrrole-containing squaraine dyes.

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3

Gao, Meng, Wenting Zhao, Hongyi Zhao, Ziyun Lin, Dongfeng Zhang y Haihong Huang. "An efficient and facile access to highly functionalized pyrrole derivatives". Beilstein Journal of Organic Chemistry 14 (20 de abril de 2018): 884–90. http://dx.doi.org/10.3762/bjoc.14.75.

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A straightforward and one-pot synthesis of pyrrolo[3,4-c]pyrrole-1,3-diones via Ag(I)-catalyzed 1,3-dipolar cycloaddition of azomethine ylides with N-alkyl maleimide, followed by readily complete oxidation with DDQ, has been successfully developed. Further transformation with alkylamine/sodium alkoxide alcohol solution conveniently afforded novel polysubstituted pyrroles in good to excellent yields. This methodology for highly functionalized pyrroles performed well over a broad scope of substrates. It is conceivable that this efficient construction method for privileged pyrrole scaffolds could deliver more active compounds for medicinal chemistry research.

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4

Quiclet-Sire, Béatrice y Samir Zard. "Convergent Routes to Pyrroles Exploiting the Unusual Radical Chemistry of Xanthates – An Overview". Synlett 28, n.º 20 (21 de julio de 2017): 2685–96. http://dx.doi.org/10.1055/s-0036-1590809.

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Convergent routes to a variety of pyrroles involving radical additions of xanthates are described. Emphasis is placed on reactions leading to the formation of 1,4-diketones or 1,4-ketoaldehydes or their synthetic equivalents, which can then be condensed with ammonia or primary amines in a variation of the classical Paal–Knorr synthesis of pyrroles. The modification of pyrroles by direct radical addition is also discussed.1 Introduction2 Earlier Routes to Pyrroles3 The Xanthate Radical Addition–Transfer Process4 Application to Pyrrole Synthesis5 Further Variations6 Direct Modification of Existing Pyrrole Rings7 Outlook and Perspectives

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5

Black, DS y RJ Strauch. "Nitrones and Oxaziridines. XL. Oxidation of 2H-Pyrroles and 3-Benzoyloxy-1-pyrrolines". Australian Journal of Chemistry 42, n.º 5 (1989): 699. http://dx.doi.org/10.1071/ch9890699.

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Peracid oxidation of 2H-pyrroles (1a-d) gave the related 2H-pyrrole 1-oxides (2a-d). Similar oxidation of the 3-benzoyloxy-1-pyrroline (7a) also gave a 2H-pyrrole 1-oxide (9), while other benzoyloxy pyrrolines (7b,c) yielded the related oxaziridines (8b,c). Some other oxygenated by-products were also identified.

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6

Taniguchi, Masahiko y Jonathan S. Lindsey. "Diversity, isomer composition, and design of combinatorial libraries of tetrapyrrole macrocycles". Journal of Porphyrins and Phthalocyanines 16, n.º 01 (enero de 2012): 1–13. http://dx.doi.org/10.1142/s1088424612004628.

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Combinatorial libraries of substituted tetrapyrrole macrocycles, which can now be prepared via a variety of approaches, typically are rich in isomers. Terminology for describing such isomers (due to distinct patterns of peripheral substituents) is delineated in several illustrative examples. A hierarchical relationship exists of molecular formula, condensed formula(s) of substituents, set(s) of pyrrole collocates (conveying each pair of β-pyrrolic substituents), and isomers of substituted tetrapyrrole macrocycles. Isomers with identical pyrrole collocate sets can arise owing to distinct positions or orientations of the (homo- or hetero-substituted) pyrrolic units in a macrocycle. Consideration of a handful of virtual combinatorial libraries illustrates tradeoffs of library size, chemical richness, and isomeric content. As one example, octa-derivatization of a tetrapyrrole scaffold with eight reactants A–H affords 2,099,728 members (99.7% isomers, 82,251 pyrrole collocate sets, and 6,435 condensed formulas) whereas the reversible self-condensation of four pyrroles that bear the same eight entities (AB, CD, EF, GH) affords 538 members (93.5% isomers, 35 pyrrole collocate sets, and 35 condensed formulas). Derivatization affords all combinations and permutations whereas self-condensation of substituted pyrroles carries collocational restrictions. Understanding such tradeoffs and the structural origin of isomerism are important aspects in the design of tetrapyrrole combinatorial libraries.

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7

Iqbal, Sarosh, Hina Rasheed, Rabiya Javed Awan, Ramsha Javed Awan, Asma Mukhtar y Mark G. Moloney. "Recent Advances in the Synthesis of Pyrroles". Current Organic Chemistry 24, n.º 11 (11 de septiembre de 2020): 1196–229. http://dx.doi.org/10.2174/1385272824999200528125651.

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: Pyrroles are the most prevalent heterocyclic compounds, which are present as the basic cores in many natural products, such as vitamin B12, bile pigments like bilirubin and biliverdin, the porphyrins of heme, chlorophyll, chlorins, bacteriochlorins, and porphyrinogens. The biological activities of compounds having pyrrole analogs include antimicrobial (antibacterial, antifungal), anti-cancer (anti-cytotoxic, antimitotic), anti-tumor, anti-hyperlipidemic, anti-depressant, anti-inflammatory, antihyperglycemic, antiproliferative, anti-HIV and anti-viral activities. Accordingly, significant attention has been paid to develop competent methods for the synthesis of pyrroles with improved yields in short times. This review gives an overview of different methods for the synthesis of pyrrole using easily available precursors using the following routes. . Synthesis of monosubstituted pyrrole using 2,5-dimethoxyfuran . Synthesis of pyrrole using dialkylacetylene dicarboxylate . Synthesis of pyrroles using β-ketoester . Synthesis of pyrrole using 1,2-dicarbonyl compounds . Synthesis of pyrroles using 1,3-dicarbonyl compounds . Synthesis of pyrroles using 1,3-dicarbonyl, amine, nitro and aldehyde group . Synthesis of pyrroles using 1,4-dicarbonyl compound and amines . Synthesis of pyrrole using enones . Synthesis of pyrroles using moieties having acetylene group

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8

Tam, Teck Lip Dexter, Ting Ting Lin y Steven Lukman. "Understanding the Excited State Photophysics of Pyrrolopyrrole-Dione Isomers and Derivatives Using Time-Dependence Density Functional Theory". Journal of Molecular and Engineering Materials 05, n.º 03 (septiembre de 2017): 1750009. http://dx.doi.org/10.1142/s2251237317500095.

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The ability to understand and predict excited state photophysics is vital for the development of photo- and electroluminescence materials, as well as light harvesting materials and photodynamic therapy. Herein, we demonstrate that single determinant time-dependent density functional theory can be computationally cost-effective and has the ability to explain both experimental singlet and triplet dynamics of pyrrolo[3,4-[Formula: see text]]pyrrole-1,4-dione and pyrrolo[3,2-b]pyrrole-2,5-dione isomers with intriguing photophysical properties. We also used the methodology to predict the photophysical properties of pyrrolo[3,4-c]pyrrole-1,3-dione and a hypothetical hybrid pyrrolo[3,4-b]pyrrole-2,4-dione isomers.

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9

Bi, Wenzhao, Geeng-Fu Jang, Lei Zhang, John W. Crabb, James Laird, Mikhail Linetsky y Robert G. Salomon. "The Adductomics of Isolevuglandins: Oxidation of IsoLG Pyrrole Intermediates Generates Pyrrole–Pyrrole Crosslinks and Lactams". High-Throughput 8, n.º 2 (10 de mayo de 2019): 12. http://dx.doi.org/10.3390/ht8020012.

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Isoprostane endoperoxides generated by free radical-induced oxidation of arachidonates, and prostaglandin endoperoxides generated through enzymatic cyclooxygenation of arachidonate, rearrange nonenzymatically to isoprostanes and a family of stereo and structurally isomeric γ-ketoaldehyde seco-isoprostanes, collectively known as isolevuglandins (isoLGs). IsoLGs are stealthy toxins, and free isoLGs are not detected in vivo. Rather, covalent adducts are found to incorporate lysyl ε-amino residues of proteins or ethanolamino residues of phospholipids. In vitro studies have revealed that adduction occurs within seconds and is uniquely prone to cause protein–protein crosslinks. IsoLGs accelerate the formation of the type of amyloid beta oligomers that have been associated with neurotoxicity. Under air, isoLG-derived pyrroles generated initially are readily oxidized to lactams and undergo rapid oxidative coupling to pyrrole–pyrrole crosslinked dimers, and to more highly oxygenated derivatives of those dimers. We have now found that pure isoLG-derived pyrroles, which can be generated under anoxic conditions, do not readily undergo oxidative coupling. Rather, dimer formation only occurs after an induction period by an autocatalytic oxidative coupling. The stable free-radical TEMPO abolishes the induction period, catalyzing rapid oxidative coupling. The amine N-oxide TMAO is similarly effective in catalyzing the oxidative coupling of isoLG pyrroles. N-acetylcysteine abolishes the generation of pyrrole–pyrrole crosslinks. Instead pyrrole-cysteine adducts are produced. Two unified single-electron transfer mechanisms are proposed for crosslink and pyrrole-cysteine adduct formation from isoLG-pyrroles, as well as for their oxidation to lactams and hydroxylactams.

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10

Isbera, Mostafa, Balázs Bognár, Ferenc Gallyas, Attila Bényei, József Jekő y Tamás Kálai. "Syntheses and Study of a Pyrroline Nitroxide Condensed Phospholene Oxide and a Pyrroline Nitroxide Attached Diphenylphosphine". Molecules 26, n.º 14 (19 de julio de 2021): 4366. http://dx.doi.org/10.3390/molecules26144366.

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The reaction of a diene nitroxide precursor with dichlorophenylphosphine in a McCormac procedure afforded 1,1,3,3-tetramethyl-5-phenyl-1,2,3,4,5,6-hexahydrophospholo[3,4-c]pyrrole-5-oxide-2-oxyl. Lithiation of the protected 3-iodo-pyrroline nitroxide followed by treatment with chlorodiphenylphosphine after deprotection afforded (1-oxyl-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-3-yl)diphenylphosphine oxide, and after reduction, (1-oxyl-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-3-yl)diphenylphosphine was realized, which was also supported by X-ray single crystal diffraction measurements. This pyrroline diphenylphosphine derivative was converted to hexadecylphosphonium salt, which is an analogue of antineoplastic agent, MITO-CP.

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11

Reinus, Brandon y Sean Kerwin. "A Copper-Catalyzed N-Alkynylation Route to 2-Substituted N-Alkynyl Pyrroles and Their Cyclization into Pyrrolo[2,1-c]oxazin-1-ones: A Formal Total Synthesis of Peramine". Synthesis 49, n.º 11 (14 de marzo de 2017): 2544–54. http://dx.doi.org/10.1055/s-0036-1588736.

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Screening of a variety of ligands and reaction conditions for the copper-catalyzed cross-coupling of alkynyl bromides with pyrroles, reveals that the use of the phenanthroline ligand 4,7-dimethoxy-1,10-phenanthroline affords a range of ynpyrroles in good to moderate yields. Furthermore, the utility of these ynpyrroles is demonstrated in the preparation of a series of pyrrolo[2,1-c][1,4]oxazin-1-ones and a formal total synthesis of the pyrrole natural product peramine.

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12

Chen, Fang, Parveen Akhtar, Leon A. P. Kane-Maguire y Gordon G. Wallace. "Synthesis and Characterization of Chiral Conducting Polymers Based on Polypyrrole". Australian Journal of Chemistry 50, n.º 9 (1997): 939. http://dx.doi.org/10.1071/c96189.

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A range of optically active pyrrole monomers have been synthesized in which a chiral sub- stituent is covalently bonded either to the pyrrole N or C3 ring position, namely (–)-(1R)-4-methyl-N-(1-phenylethyl)pyrrole-3-carboxamide, (+)-(1S)-4-methyl-N-(1-phenylethyl)pyrrole-3-carboxamide, (–)-(1R)-4-methyl-N-(1-naphthylethyl)pyrrole-3-carboxamide, (+)-(1S)-4-methyl-N-(1-naphthylethyl)pyrrole-3-carboxamide, (+)-(2S)-2-(1H-pyrrol-1-yl)propionic acid, (+)-(1S)-N-(1-phenyl-ethyl)pyrrole, and (–)-(1R)-N-(1-phenylethyl)pyrrole. Their chiroptical properties have been established by circular dichroism spectroscopy. Electropolymerization of the three N-substituted pyrrole monomers provided films of chiral conducting polymers, whose electrical and spectroscopic properties are described. Although oxidation of the C3 substituted pyrrole monomers was also facile, electrodeposition was poor and films of the associated polymers could not be obtained.

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13

Hu, Fan, Jerome Ng y Pauline Chiu. "Pyrroles as Dienes in (4+3) Cycloadditions". Synthesis 51, n.º 05 (6 de febrero de 2019): 1073–86. http://dx.doi.org/10.1055/s-0037-1611660.

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This short review summarizes the examples to date of successful (4+3) cycloadditions, including formal (4+3) cycloadditions, where pyrrole derivatives reacted as the diene component, to provide aza-bridged bicyclic and polycyclic adducts.1 Introduction2 Unsubstituted Pyrroles as Dienes in (4+3) Cycloadditions3 C-Substituted Pyrroles as Dienes in (4+3) Cycloadditions4 Intramolecular Pyrrole (4+3) Cycloadditions5 Conclusions

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14

Krutošíková, Alžbeta y Mikuláš Hanes. "Substituted 4-Benzylfuro[3,2-b]pyrroles". Collection of Czechoslovak Chemical Communications 57, n.º 7 (1992): 1487–94. http://dx.doi.org/10.1135/cccc19921487.

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Preparation of 4-benzylfuro[3,2-b]pyrroles is described and their reactions with selected dienophiles are discussed. Utilization of 4-acetylfuro[3,2-b]pyrroles for preparation of 4-substituted derivatives of furo[3,2-b]pyrrole and the synthesis of ethyl 4-(2- and 4-nitrobenzyl)furo[3,2-b]pyrrole-5-carboxylates for fusing to a 1,4-diazepine system is presented.

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15

Kumar, Anil, Israr Ahmad y M. Sudershan Rao. "Ytterbium(III) triflate catalyzed synthesis of calix[4]pyrroles in ionic liquids". Canadian Journal of Chemistry 86, n.º 9 (1 de septiembre de 2008): 899–902. http://dx.doi.org/10.1139/v08-121.

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Ytterbium(III) triflate has been utilized as a mild Lewis-acid catalyst for the synthesis of various calix[4]pyrroles by the condensation of pyrrole with different ketones in ionic liquids. The calix[4]pyrroles were obtained in high yield under ecofriendly, economical, and noncorrosive conditions, and the catalyst was recovered and recycled.Key words: calix[4]pyrrole, ionic liquid, ytterbium triflate.

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16

Cordero, Franca, Bhushan Khairnar, Anna Ranzenigo y Alberto Brandi. "Cycloaddition of Benzyne with Alkoxy-Substituted Pyrroline-N-oxides: Unexpected Rearrangement to an N-Phenylpyrrole". SynOpen 02, n.º 01 (enero de 2018): 0025–29. http://dx.doi.org/10.1055/s-0037-1609082.

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Reaction of enantiopure 3,4-dialkoxy-pyrroline N-oxides with benzyne affords the expected tetrahydrobenzo[d]pyrrolo[1,2-b]isoxazoles along with an unexpected 2,3-disubstitued-N-phenyl-pyrrole derived from an unprecedented rearrangement of the adduct of nitrone with two molecules of benzyne. A mechanism for the unusual rearrangement is proposed. The benzo[d]isoxazolidine derivatives are conveniently converted into 2-(2-hydroxyphenyl)-3,4-dialkoxypyrrolidines by reductive opening of the N–O bond.

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17

Kucukdisli, Murat, Dorota Ferenc, Marcel Heinz, Christine Wiebe y Till Opatz. "Simple two-step synthesis of 2,4-disubstituted pyrroles and 3,5-disubstituted pyrrole-2-carbonitriles from enones". Beilstein Journal of Organic Chemistry 10 (24 de febrero de 2014): 466–70. http://dx.doi.org/10.3762/bjoc.10.44.

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The cyclocondensation of enones with aminoacetonitrile furnishes 3,4-dihydro-2H-pyrrole-2-carbonitriles which can be readily converted to 2,4-disubstituted pyrroles by microwave-induced dehydrocyanation. Alternatively, oxidation of the intermediates produces 3,5-disubstituted pyrrole-2-carbonitriles.

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18

Harris, RLN y HG Mcfadden. "Fused Heterocycles From Pyrrolethiols. Thieno[2,3-B]Pyrroles, Thieno[3,2-B]Pyrroles and Thiazolo[3,2-a]Pyrroles From Pyrrol-2-Yl Phenacyl Sulfides". Australian Journal of Chemistry 39, n.º 6 (1986): 887. http://dx.doi.org/10.1071/ch9860887.

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A reinvestigation of the cyclization of pyrrol-2-yl phenacyl sulfides in polyphosphoric acid has shown that the major product is a thieno[3,2-b]pyrrole, where rearrangement of the sulfur substituent from position 2 to position 3 has preceded cyclization. When TiCl4 is used as cyclocondensation reagent minimal rearrangement is observed and the product obtained is either a thiazolo[3,2-a]pyrrole when the pyrrole nitrogen is unsubstituted, or a thieno[2,3-b]pyrrole where an N-substituent is present.

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19

Tedjar, Farouk, Salah Ymmel, Miroslav Janda, Petr Duchek, Petr Holý y Ivan Stibor. "Electrochemical oxidation of pyrrole derivatives in alcoholic medium". Collection of Czechoslovak Chemical Communications 54, n.º 5 (1989): 1299–305. http://dx.doi.org/10.1135/cccc19891299.

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Electrochemical oxidation of pyrrole (I), 1-methylpyrrole (II), 1,2,5-trimethylpyrrole (III), methyl 1-methyl-2-pyrrolecarboxylate (IV) and diethyl 3,5-dimethyl-2,4-pyrroledicarboxylate (V) has been studied. An advantageous method of preparation of polypyrroles (PP) and conductive PVC-PP composites has been elaborated, permitting a 20 fold starting concentration of the monomer. Electrooxidation of II in methanol leads either to 5,5-dimethoxy-1-methyl-3-pyrrolin-2-one (VII) or 1-methyl-2,2,5,5-tetramethoxy-3-pyrroline (VI), their ratio depending on water content in the alcohol used. Oxidation of IV affords the analogous 5-carbomethoxy-5-methoxy-1-methyl-3-pyrrolin-2-one (X), oxidation of III and V leads to products of substitution at the methyl groups.

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20

Pravardhan Reddy, E., A. Sumankumar, B. Sridhar, Y. Hemasri, Y. Jayaprakash Rao y B. V. Subba Reddy. "1,5-Electrocyclization of conjugated azomethine ylides derived from 3-formyl chromene and N-alkyl amino acids/esters". Organic & Biomolecular Chemistry 15, n.º 36 (2017): 7580–83. http://dx.doi.org/10.1039/c7ob00705a.

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A novel strategy has been developed for the synthesis of chromeno[3,4-b]pyrrol-4(3H)-one and substituted pyrrole derivatives. This is the first example of the preparation of highly substituted pyrrole derivatives from chromene-3-carboxaldehydes.

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21

Antonyová, Veronika, Ameneh Tatar, Tereza Brogyányi, Zdeněk Kejík, Robert Kaplánek, Fréderic Vellieux, Nikita Abramenko et al. "Targeting of the Mitochondrial TET1 Protein by Pyrrolo[3,2-b]pyrrole Chelators". International Journal of Molecular Sciences 23, n.º 18 (16 de septiembre de 2022): 10850. http://dx.doi.org/10.3390/ijms231810850.

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Targeting of epigenetic mechanisms, such as the hydroxymethylation of DNA, has been intensively studied, with respect to the treatment of many serious pathologies, including oncological disorders. Recent studies demonstrated that promising therapeutic strategies could potentially be based on the inhibition of the TET1 protein (ten-eleven translocation methylcytosine dioxygenase 1) by specific iron chelators. Therefore, in the present work, we prepared a series of pyrrolopyrrole derivatives with hydrazide (1) or hydrazone (2–6) iron-binding groups. As a result, we determined that the basic pyrrolo[3,2-b]pyrrole derivative 1 was a strong inhibitor of the TET1 protein (IC50 = 1.33 μM), supported by microscale thermophoresis and molecular docking. Pyrrolo[3,2-b]pyrroles 2–6, bearing substituted 2-hydroxybenzylidene moieties, displayed no significant inhibitory activity. In addition, in vitro studies demonstrated that derivative 1 exhibits potent anticancer activity and an exclusive mitochondrial localization, confirmed by Pearson’s correlation coefficient of 0.92.

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22

Pelkey, Erin T. y Gordon W. Gribble. "Novel electrophilic ipso acylation - detosylation reaction of pyrroles". Canadian Journal of Chemistry 84, n.º 10 (1 de octubre de 2006): 1338–42. http://dx.doi.org/10.1139/v06-075.

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A pyrrole and two pyrroloindoles that are substituted with a p-toluenesulfonyl group undergo an ipso acylation – detosylation reaction with acid chlorides and aluminum chloride to afford the corresponding acyl-substituted pyrroles and pyrroloindoles.Key words: pyrrole, pyrroloindole, ipso acylation, detosylation, Friedel–Crafts reaction.

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23

Yu, Qixin, Xiaoyu Li, Xinyue Wang y Jianhui Liu. "Regioselective Synthesis of 2,5-Disubstituted Pyrroles via Stepwise Iododesilylation and Coupling Reactions". Australian Journal of Chemistry 71, n.º 3 (2018): 95. http://dx.doi.org/10.1071/ch17341.

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A new protocol has been developed for the regioselective preparation of 2,5-disubstituted pyrroles. This approach is based on a stepwise iododesilylation and a subsequent coupling reaction, involving a 6-step pathway starting from the simplest pyrrole. A variety of 2,5-disubstituted pyrrole derivatives are accessible in moderate to good yields. In this study, the protection group for the pyrrole nitrogen is carefully chosen and N,N-dimethylaminosulfonyl is the final choice, which facilitates the subsequent double lithiation and makes the pyrrole moiety more stable. However, the attempted removal of this group fails under several different conditions. Instead, unexpected dimethylaminosulfonyl migration to the β-position of the pyrrole ring in the presence of tetrabutylammonium fluoride is observed.

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24

He, Yan-Hong, Gang-Qiang Wang, Ke-Ling Xu y Zhi Guan. "An Efficient Procedure for the Synthesis of Polysubstituted Pyrroles in an Ionic Liquid". Zeitschrift für Naturforschung B 66, n.º 2 (1 de febrero de 2011): 191–96. http://dx.doi.org/10.1515/znb-2011-0212.

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The ionic liquid 1-butyl-3-methyl-imidazolium hydrogen sulfate, [bmim]HSO4, was used as a catalyst and reaction medium for the pyrrole synthesis, and a wide range of aliphatic, aromatic, heteroaromatic and carboxylic 1,4-diketones easily underwent condensations with aniline and ethylenediamine to form polysubstituted pyrroles. Sequential decarboxylation/Paal-Knorr pyrrole condensation was observed, which provides a new and facile approach to monoester pyrroles from 1,4-diketo-2,3-dicarboxylic acid esters.

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25

Jux, Norbert, Daniel Gryko, Rafał Stężycki, David Reger y Helen Hoelzel. "Synthesis and Photophysical Properties of Hexaphenylbenzene–Pyrrolo[3,2-b]pyrroles". Synlett 29, n.º 19 (26 de septiembre de 2018): 2529–34. http://dx.doi.org/10.1055/s-0037-1610286.

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Methods for the synthesis of pyrrolo[3,2-b]pyrroles containing hexaphenylbenzene moieties at the 2- and 5-positions or the 1- and 4-positions have been developed. It was shown that placing a hexaphenylbenzene moiety at the 2- and 5-positions requires a Diels–Alder reaction between an alkyne-substituted pyrrolopyrrole core and a 2,3,4,5-tetraphenylcyclopenta-2,4-dien-1-one. The resulting dyes show a strong blue fluorescence that was hypsochromically shifted by chlorination at the 3- and 6-positions. The overall conjugation between the hexaphenylbenzene moieties and the pyrrolopyrrole core is limited, as evident from their photophysical properties. The hexaphenylbenzene moieties attached to the pyrrolo[3,2-b]pyrrole core could not be transformed into hexa-peri-hexabenzocoronenes through intramolecular oxidative aromatic coupling.

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26

Mai, Huyen Le Thi, Nhung Thanh Thi Truong, Thiet Quoc Nguyen, Bao Kim Doan, Dat Hung Tran, Le-Thu T. Nguyen, Woosung Lee et al. "Synthesis and characterization of donor–acceptor semiconducting polymers containing 4-(4-((2-ethylhexyl)oxy)phenyl)-4H-dithieno[3,2-b:2′,3′-d]pyrrole for organic solar cells". New Journal of Chemistry 44, n.º 39 (2020): 16900–16912. http://dx.doi.org/10.1039/d0nj02616f.

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D–A polymers containing 4-(4-((2-ethylhexyl)oxy)phenyl)-4H-dithieno[3,2-b:2′,3′-d]pyrrole and 2,5-bis(2-ethylhexyl)-3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione were successfully synthesized and applied for organic solar cells.

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27

Menéndez, J., Marco Leonardi, Verónica Estévez y Mercedes Villacampa. "The Hantzsch Pyrrole Synthesis: Non-conventional Variations and Applications of a Neglected Classical Reaction". Synthesis 51, n.º 04 (3 de diciembre de 2018): 816–28. http://dx.doi.org/10.1055/s-0037-1610320.

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Pyrrole is one of the most important one-ring heterocycles because of its widespread presence in natural products and unnatural bioactive compounds and drugs in clinical use. The preparation of pyrroles by reaction between primary amines, β-dicarbonyl compounds, and α-halo ketones, known as the Hantzsch pyrrole synthesis, is reviewed here for the first time. In spite of its age and its named reaction status, this method has received little attention in the literature. Recent work involving the use of non-conventional conditions has rejuvenated this classical reaction and this is emphasized in this review. Some applications of the Hantzsch reaction in target-oriented synthesis are also discussed.1 Introduction2 The Conventional Hantzsch Pyrrole Synthesis3 Hantzsch Pyrrole Synthesis under Non-conventional Conditions4 Applications of the Hantzsch Pyrrole Synthesis5 Conclusions

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28

Black, DSC y RJ Strauch. "Nitrones and Oxaziridines. XXXVII. Some Oxidation Reactions of 1-Pyrroline 1-Oxides". Australian Journal of Chemistry 41, n.º 2 (1988): 183. http://dx.doi.org/10.1071/ch9880183.

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The 2,4-diaryl-1-pyrroline 1-oxides (4) can be converted into the related 2H-pyrrole 1-oxides (5) by treatment with N-bromosuccinimide and anhydrous potassium carbonate. Similar treatment of the 1-pyrroline 1-oxide (6) yielded the succinimido-substituted pyrroline (7). Selenium dioxide oxidation of the tetramethyl nitrone (8) under various conditions gave mixtures containing the compounds (10)-(12). Neither process provides a general conversion of 1-pyrroline 1-oxides into 2H-pyrrole 1-oxides.

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29

Allen, Annette D., Jean-Marc Kwong-Chip, Wing Cheung Lin, Paul Nguyen y Thomas T. Tidwell. "Formation and reactivity of 1-pyrrolyl-2,2,2-trifluoroethyl cations". Canadian Journal of Chemistry 68, n.º 10 (1 de octubre de 1990): 1709–13. http://dx.doi.org/10.1139/v90-265.

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1-(1-Methyl-2-pyrrolyl)-2,2,2-trifluoroethyl p-nitrobenzoate (3) reacts by carbocation formation with an m value for the dependence of rate on the solvent polarity parameter YOTs of 0.56, and a rate 41 times slower than (1-methyl-2-pyrrolyl)methyl p-nitrobenzoate. The products from 3 include significant amounts of material derived from solvent attack at the 5-position of the pyrrole ring. The results indicate a high degree of charge delocalization by the strongly donating pyrrolyl group, resulting in a low k(H)/k(CF3) rate ratio and nucleophilic attack on the ring. 1,1, l-Trifluoro-2-(1-methyl-2-pyrrolyl)propan-2-ol (10) reacted with CF3CO2H via a tertiary carbocation, which led to dimeric products resulting from electrophilic substitution on the pyrrole ring. Keywords: pyrrole, trifluoromethyl substituents, carbocations.

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30

Martyn, Derek C. y Andrew D. Abell. "The Synthesis and Testing of α-(Hydroxymethyl)pyrroles as DNA Binding Agents". Australian Journal of Chemistry 57, n.º 11 (2004): 1073. http://dx.doi.org/10.1071/ch04183.

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The α-(hydroxymethyl)pyrroles 16a and 16b were prepared and shown to be cytotoxic against the P388 cancer cell line. Ethyl 5-hydroxymethyl-1H-pyrrole-2-carboxylate 18 was inactive, demonstrating that an α-(hydroxymethyl)pyrrole group alone is not sufficient for activity. Compound 16b has been shown to bind to DNA with reasonable affinity.

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31

Li, Zhaopeng, Johan van Lier y Clifford C. Leznoff. "Heterocyclic aromatic amide protecting groups for aryl and phthalocyaninesulfonic acids". Canadian Journal of Chemistry 77, n.º 1 (1 de enero de 1999): 138–45. http://dx.doi.org/10.1139/v98-219.

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Pyrroles, indole, imidazole, and a pyrazole were treated with 3,4-dibromobenzenesulfonyl chloride to form 3,4-dibromobenzenesulfonamides. The 1-(3,4-dibromophenylsulfonyl)pyrrole and 1-(3,4-dibromophenylsulfonyl)indole were stable to CuCN in DMF to produce 1-(3,4-dicyanophenylsulfonyl)pyrrole and 1-(3,4-dicyanophenylsulfonyl)indole, which upon treatment with ammonia in 2-N,N-dimethylaminoethanol gave the protected phthalocyanine-2,9,16,23- tetrasulfonamides. Base cleavage of these sulfonamides yielded the free acids. A mixed condensation of 4,5-diheptylphthalonitrile and 1-(3,4-dicyanophenylsulfonyl)pyrrole gave 9,10,16,17,23,24-hexakis(1-heptyl)-2-(1- pyrrolylsulfonyl)phthalocyanine. Cleavage of the latter yielded the lithium salt of the monosulfonic acid.Key words: sulfonic acid blocking groups, phthalocyanine sulfonic acids, 1-(3,4-dicyanophenylsulfonyl)pyrrole, 1-(3,4-dicyanophenylsulfonyl)indole.

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32

Clark, J. Caleb, Bruno Fabre, Frank R. Fronczek y M. Graça H. Vicente. "Syntheses and properties of carboranylpyrroles". Journal of Porphyrins and Phthalocyanines 09, n.º 11 (noviembre de 2005): 803–10. http://dx.doi.org/10.1142/s1088424605000915.

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Synthetic routes to mono- and di-carboranylpyrroles (1-5) bearing the carborane groups linked either directly to the 3- and/or 4-positions of the pyrrole ring or via one or two methylene spacers are described. Several X-ray structures of key intermediates are presented and discussed. Carboranylpyrroles can be cyclotetramerized to afford carboranylporphyrins in low to moderate yields, depending on the number of carborane cages and their linkage to the pyrrole ring. The best yields of porphyrin were obtained with pyrrole 3, bearing a two carbon spacer between the carborane and pyrrole units. The electrochemical polymerization of pyrroles 2 and 3 gave functionalized conducting polymer films with increased overoxidation resistance and thermal stability compared with unsubstituted polypyrrole. Dicarboranylpyrrole 4 did not electropolymerize under a variety of experimental conditions, whereas pyrrole 5 formed only soluble oligomers.

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33

Sakamoto, Toshio, Ayaka Nishida, Naoki Wada, Yutaka Nakamura, Shinji Sato, Tetsuya Konishi y Seiichi Matsugo. "Identification of a Novel Pyrrole Alkaloid from the Edible Mushroom Basidiomycetes-X (Echigoshirayukidake)". Molecules 25, n.º 21 (22 de octubre de 2020): 4879. http://dx.doi.org/10.3390/molecules25214879.

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Three pyrrole alkaloid derivatives were isolated from the edible mushroom Basidiomycetes-X (Echigoshirayukidake) by water extraction followed by ethyl acetate fractionation. The chemical structures determined by MS and NMR were 4-[2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl] butanoic acid (compound I), 4-[2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl] butanamide (compound II), and 5-(hydroxymethyl)-1H-pyrrole-2-carboxaldehyde (compound III). Compound I was found to be the major component, followed by compound II, and compound III was the minor component. The dry powder of Basidiomycetes-X contained approximately 825 μg g−1 compound I and 484 μg g−1 compound II. Compound II was found to be a novel pyrrole aldehyde homologue not previously reported and thus is a specific component of this mushroom.

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34

Bray, Brian L. y Joseph M. Muchowski. "α-(Dialkylamino)-α-pyrrolylacetonitriles. A potpourri of useful synthetic transformations". Canadian Journal of Chemistry 68, n.º 8 (1 de agosto de 1990): 1305–8. http://dx.doi.org/10.1139/v90-201.

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α-(Dialkylamino)-α-(pyrrol-2-yl)acetonitriles (3) are versatile intermediates that are readily converted into regiochemically pure 2-bromo-6-dialkylamino-1-azafulvenes and 5-bromo-2-acylpyrroles (acyl = CHO, COR). In addition, 3 (R1 = H), 4 (R1 = H), and the β-substituted compound 9 are transformed easily and under mild conditions, via the corresponding α-methylthio compounds (e.g., 7a), into the methyl pyrrole carboxylates 8a, 8b, and 10, respectively. Keywords: α-(dialkylamino)-α-(pyrrol-2-yl)acetonitriles, 5-bromo-2-acylpyrroles, methyl pyrrole carboxylates.

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35

Macías, Mario A., Juan-Carlos Castillo y Jaime Portilla. "A series of (E)-5-(arylideneamino)-1-tert-butyl-1H-pyrrole-3-carbonitriles and their reduction products to secondary amines: syntheses and X-ray structural studies". Acta Crystallographica Section C Structural Chemistry 74, n.º 1 (1 de enero de 2018): 82–93. http://dx.doi.org/10.1107/s2053229617017260.

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An efficent access to a series of N-(pyrrol-2-yl)amines, namely (E)-1-tert-butyl-5-[(4-chlorobenzylidene)amino]-1H-pyrrole-3-carbonitrile, C16H16ClN3, (7a), (E)-1-tert-butyl-5-[(2,4-dichlorobenzylidene)amino]-1H-pyrrole-3-carbonitrile, C16H15Cl2N3, (7b), (E)-1-tert-butyl-5-[(pyridin-4-ylmethylene)amino]-1H-pyrrole-3-carbonitrile, C15H16N4, (7c), 1-tert-butyl-5-[(4-chlorobenzyl)amino]-1H-pyrrole-3-carbonitrile, C16H18ClN3, (8a), and 1-tert-butyl-5-[(2,4-dichlorobenzyl)amino]-1H-pyrrole-3-carbonitrile, C16H17Cl2N3, (8b), by a two-step synthesis sequence (solvent-free condensation and reduction) starting from 5-amino-1-tert-butyl-1H-pyrrole-3-carbonitrile is described. The syntheses proceed via isolated N-(pyrrol-2-yl)imines, which are also key synthetic intermediates of other valuable compounds. The crystal structures of the reduced compounds showed a reduction in the symmetry compared with the corresponding precursors, viz. Pbcm to P\overline{1} from compound (7a) to (8a) and P21/c to P\overline{1} from compound (7b) to (8b), probably due to a severe change in the molecular conformations, resulting in the loss of planarity observed in the nonreduced compounds. In all of the crystals, the supramolecular assembly is controlled mainly by strong (N,C)—H...N hydrogen bonds. However, in the case of (7a)–(7c), C—H...Cl interactions are strong enough to help in the three-dimensional architecture, as observed in Hirshfeld surface maps.

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36

More, Satish S., T. Krishna Mohan, Y. Sateesh Kumar, U. K. Syam Kumar y Navin B. Patel. "Synthesis of novel 5-alkyl/aryl/heteroaryl substituted diethyl 3,4-dihydro-2H-pyrrole-4,4-dicarboxylates by aziridine ring expansion of 2-[(aziridin-1-yl)-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters". Beilstein Journal of Organic Chemistry 7 (20 de junio de 2011): 831–38. http://dx.doi.org/10.3762/bjoc.7.95.

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A novel synthetic methodology has been developed for the synthesis of diethyl 5-alkyl/aryl/heteroaryl substituted 3,4-dihydro-2H-pyrrole-4,4-dicarboxylates (also called 2-substituted pyrroline-4,5-dihydro-3,3-dicarboxylic acid diethyl esters) by iodide ion induced ring expansion of 2-[(aziridin-1-yl)-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters in very good to excellent yields under mild reaction conditions. The electronic and steric impact of the substituents on the kinetics of ring expansion of N-vinyl aziridines to pyrrolines has been studied. Various diversely substituted novel pyrroline derivatives have been synthesized by this methodology and the products can be used as key intermediates in the synthesis of substituted pyrrolines, pyrroles and pyrrolidines.

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37

Mohamed, Mosaad S., Aymn E. Rashad, Mostafa Adbel-Monem y Samar S. Fatahalla. "New Anti-Inflammatory Agents". Zeitschrift für Naturforschung C 62, n.º 1-2 (1 de febrero de 2007): 27–31. http://dx.doi.org/10.1515/znc-2007-1-205.

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The pyrrole derivatives 1a, b and 2a, b were used as precursors for the preparation of N-substituted pyrrole derivatives 3a, b-9a, b and pyrrolo[2,3-d]pyrimidines 13-16. Also, all the newly prepared products were tested for anti-inflammatory activity as analogues to fenamates, and some of them revealed moderate anti-inflammatory activity compared to the standard drug indomethacin.

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38

Antonucci, T., J. S. Warmus, J. C. Hodges y D. G. Nickell. "Characterization of the Antiviral Activity of Highly Substituted Pyrroles: A Novel Class of Non-Nucleoside HIV-1 Reverse Transcriptase Inhibitor". Antiviral Chemistry and Chemotherapy 6, n.º 2 (abril de 1995): 98–108. http://dx.doi.org/10.1177/095632029500600204.

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As a result of mass screening of the Parke-Davis Pharmaceutical compound library for inhibitors of HIV-1 reverse transcriptase (RT) activity, a novel class of inhibitor, the pyrroles, was identified. Subsequently, a series of analogues was screened for inhibitory activity against HIV-1 and some structure-activity relationships were identified. Further characterization of the most potent pyrrole involved comparing its effects in peripheral blood lymphocytes (PBLs) with its effects in transformed cell lines; the pyrrole had the same efficacy (EC50 = approximately 2 μM) but was less toxic in PBLs (IC50 = 175 μM) than in the cell lines CEM-SS and MT-2 (IC50 = 60-70 μM). The pyrrole was active against a strain of HIV-1 resistant to AZT (strain G9106) but lost activity against both HIV-2 (strain ROD) and a strain of HIV-1 resistant to a non-nucleoside reverse transcriptase inhibitor (the pyridinone-resistant strain A17). Moreover, in direct enzymatic testing against HIV-1 RT purified from virus particles and against RT expressed recombinantly, the pyrrole showed potent inhibitory activity. We conclude that the pyrroles present a novel class of HIV-1 non-nucleoside reverse transcriptase inhibitor.

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39

Tasior, Mariusz, Khaled Hassanein, Leszek M. Mazur, Ioanna Sakellari, David Gray, Maria Farsari, Marek Samoć, Fabrizio Santoro, Barbara Ventura y Daniel T. Gryko. "The role of intramolecular charge transfer and symmetry breaking in the photophysics of pyrrolo[3,2-b]pyrrole-dione". Physical Chemistry Chemical Physics 20, n.º 34 (2018): 22260–71. http://dx.doi.org/10.1039/c8cp03755h.

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40

Palmieri, Alessandro y Marino Petrini. "Synthesis and practical applications of 2-(2-nitroalkyl)pyrroles". Organic & Biomolecular Chemistry 18, n.º 24 (2020): 4533–46. http://dx.doi.org/10.1039/d0ob00956c.

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Two main approaches can be designed for the synthesis of 2-(2-nitroalkyl)pyrroles using nitroalkenes or nitroalkanes in the reaction with pyrrole derivatives. The obtained nitroalkyl pyrroles can be converted into various bioactive compounds.

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41

Han, Ying, Chao-Guo Yan, Chang-Zhou Liu, Yuan-Yuan Zhang y Jing Sun. "Nucleophilic Phosphine-Promoted Domino Reaction of Dialkyl Acetylenedicarboxylates and 3-Arylamino-1-methyl-1H-pyrrole-2,5-diones". Synthesis 50, n.º 18 (12 de julio de 2018): 3715–22. http://dx.doi.org/10.1055/s-0037-1610438.

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The three-component reaction of triphenylphosphine, dimethyl acetylenedicarboxylate and 3-arylamino-1-methyl-1H-pyrrole-2,5-diones in CH2Cl2 at room temperature resulted in functionalized 3-(triphenyl-λ5-phosphanylidene)succinates in nearly quantitative yields. However, tri(n-butyl)phosphine promoted reaction of dialkyl acetylenedicarboxylates and 3-arylamino-1-methyl-1H-pyrrole-2,5-diones in CH2Cl2 afforded functionalized pyrrolo[3,4-b]pyridine-4-carboxylates in satisfactory yields.

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42

Sakharov, Pavel A., Nikolai V. Rostovskii, Alexander F. Khlebnikov y Mikhail S. Novikov. "Copper(II)-Catalyzed (3+2) Cycloaddition of 2H-Azirines to Six-Membered Cyclic Enols as a Route to Pyrrolo[3,2-c]quinolone, Chromeno[3,4-b]pyrrole, and Naphtho[1,8-ef]indole Scaffolds". Molecules 27, n.º 17 (2 de septiembre de 2022): 5681. http://dx.doi.org/10.3390/molecules27175681.

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A method for the [2+3] pyrroline annulation to the six-membered non-aromatic enols using 3-aryl-2H-azirines as annulation agents is developed in the current study. The reaction proceeds as a formal (3+2) cycloaddition via the N1-C2 azirine bond cleavage and is catalyzed by both Cu(II) and Cu(I) compounds. The new annulation method can be applied to prepare pyrrolo[3,2-c]quinoline, chromeno[3,4-b]pyrrole, and naphtho[1,8-ef]indole derivatives in good to excellent yields from enols of the quinolin-2-one, 2H-chromen-2-one, and 1H-phenalen-1-one series.

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43

Hawes, Chris S., Gearóid M. Ó Máille, Kevin Byrne, Wolfgang Schmitt y Thorfinnur Gunnlaugsson. "Tetraarylpyrrolo[3,2-b]pyrroles as versatile and responsive fluorescent linkers in metal–organic frameworks". Dalton Transactions 47, n.º 30 (2018): 10080–92. http://dx.doi.org/10.1039/c8dt01784k.

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44

He, Ying-Chun, Ji-Gang Pan y Dian-Sheng Liu. "Structural study of the novel deuterated calix[4]pyrrole complex d 12-meso-tetrakis(4-methoxyphenyl)-meso-tetramethylcalix[4]pyrrole–pyridine N-oxide–acetonitrile (1/1/1)". Acta Crystallographica Section C Structural Chemistry 73, n.º 3 (7 de febrero de 2017): 254–58. http://dx.doi.org/10.1107/s2053229617001309.

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Calix[4]pyrroles act as powerful receptors for electron-rich neutral guests and anionic guests in organic solvents. For the electron-rich neutral guest pyridine N-oxide, calix[4]pyrrole, with a deep cavity, provides an appropriate environment. The ability of calix[4]pyrrole to host binding guest molecules is the result of hydrogen bonding, π–π, C—H...π and hydrophobic interactions of the cavity. The novel title complex, C52H40D12N4O4·C5H5NO·C2H3N, based on d 12-meso-tetrakis(4-methoxyphenyl)-meso-tetramethylcalix[4]pyrrole, has been assembled using an excess of pyridine N-oxide and is the first deuterated complex of calix[4]pyrrole. A single-crystal X-ray study shows that the receptor adopts a cone conformation with the N-oxide fragment encapsulated deep within the cavity. 1H NMR spectroscopy was used to probe the molecular binding formation in CD3CN. The results are consistent with the single-crystal X-ray study in identifying that the pyridine N-oxide molecule occupies the cavity of the calix[4]pyrrole molecule. UV–vis spectroscopy revealed that the calix[4]pyrrole receptor molecules are able to form 1:1 inclusion complexes in CH3CN.

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45

Chen, Weiqiang, Hui-Jing Li, Qin-Ying Li y Yan-Chao Wu. "Direct oxidative coupling of N-acyl pyrroles with alkenes by ruthenium(ii)-catalyzed regioselective C2-alkenylation". Organic & Biomolecular Chemistry 18, n.º 3 (2020): 500–513. http://dx.doi.org/10.1039/c9ob02421b.

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46

Cheng, Yukun, Channing K. Klein y Ian A. Tonks. "Synthesis of pentasubstituted 2-aryl pyrroles from boryl and stannyl alkynes via one-pot sequential Ti-catalyzed [2 + 2 + 1] pyrrole synthesis/cross coupling reactions". Chemical Science 11, n.º 37 (2020): 10236–42. http://dx.doi.org/10.1039/d0sc01576h.

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47

A. A. Elbannany, Araf y Laila I. Ibrahim. "Synthesis of Pyrrole, Pyrrolidone, Pyrrolo[3,4-c]pyrazole, Pyrrolo[3,2-b]pyridine and Pyrrolo[3,2-b]pyrrole Derivatives". HETEROCYCLES 27, n.º 9 (1988): 2071. http://dx.doi.org/10.3987/com-88-4628.

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48

Zhu, Lin, Junyi Xue, Yisheng He, Qingsu Xia, Peter P. Fu y Ge Lin. "Correlation Investigation between Pyrrole-DNA and Pyrrole-Protein Adducts in Male ICR Mice Exposed to Retrorsine, a Hepatotoxic Pyrrolizidine Alkaloid". Toxins 14, n.º 6 (28 de mayo de 2022): 377. http://dx.doi.org/10.3390/toxins14060377.

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Pyrrolizidine alkaloids (PAs) have been found in over 6000 plants worldwide and represent the most common hepatotoxic phytotoxins. Catalyzed by hepatic cytochrome P450 enzymes, PAs are metabolized into reactive pyrrolic metabolites, which can alkylate cellular proteins and DNA to form pyrrole-protein adducts and pyrrole-DNA adducts, leading to cytotoxicity, genotoxicity, and tumorigenicity. To date, the correlation between these PA-derived pyrrole-protein and pyrrole-DNA adducts has not been well investigated. Retrorsine is a representative hepatotoxic and carcinogenic PA. In the present study, the correlations among the PA-derived liver DNA adducts, liver protein adducts, and serum protein adducts in retrorsine-treated mice under different dosage regimens were studied. The results showed positive correlations among these adducts, in which serum pyrrole-protein adducts were more accessible and present in higher abundance, and thus could be used as a suitable surrogate biomarker for pyrrole-DNA adducts to indicate the genetic or carcinogenic risk posed by retrorsine.

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49

Tamilavan, Vellaiappillai, Seungmin Kim, Ji Yeong Sung, Dal Yong Lee, Shinuk Cho, Youngeup Jin, Junghyun Jeong, Sung Heum Park y Myung Ho Hyun. "Effects of the incorporation of bithiophene instead of thiophene between the pyrrolo[3,4-c]pyrrole-1,3-dione units of a bis(pyrrolo[3,4-c]pyrrole-1,3-dione)-based polymer for polymer solar cells". New Journal of Chemistry 40, n.º 12 (2016): 10153–60. http://dx.doi.org/10.1039/c6nj02478e.

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50

Gabrielli, Serena, Ludovica Ciabattoni, Susanna Sampaolesi, Roberto Ballini y Alessandro Palmieri. "A new fully heterogeneous synthesis of pyrrole-2-acetic acid derivatives". RSC Advances 6, n.º 50 (2016): 44341–44. http://dx.doi.org/10.1039/c6ra05348c.

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