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Wu F, Yang S, Dai X, Gu L, Xu F, Fang X, Yu S, Ding CF. Discrimination of Aminobiphenyl Isomers in the Gas Phase and Investigation of Their Complex Conformations. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:716-724. [PMID: 33527834 DOI: 10.1021/jasms.0c00426] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The analysis of positional isomers is of great significance because their different chemical properties but similar structures make separation difficult. In this work, a simple method for simultaneously discriminating three positional isomers of 2-aminobiphenyl (2-ABP), 3-ABP, and 4-ABP was studied by ion mobility spectrometry (IMS) and quantum mechanical calculations at the molecular level. In the experiments, three ABP isomers were mixed with α-, β-, and γ-cyclodextrins (CD), and the IMS results show that the three ABP isomers were clearly recognized by the formed complex of [α-CD + ABP + H]+ via measuring their IMS, in which the different ion mobilities of 1.515, 1.544, 1.585 V·s·com-2 with the collision cross sections (CCS) of 307.3, 312.5, 320.8 Å2 were obtained for [α-CD + 2-ABP + H]+, [α-CD + 3-ABP + H]+, and [α-CD + 4-ABP + H]+, respectively. Collision induced dissociation analysis of the three [α-CD + ABP + H]+ isomer complexes were further studied, indicating that the same fragmentation process required different collisional energies, and the greater the CCS for the [α-CD + ABP + H]+ with looser structure and the smaller energy required. Besides, the favorable conformation and the CCS value of the different [CD + ABP + H]+ isomer complexes were measured via quantum mechanical calculations to detail their intermolecular interactions. It revealed that the intermolecular binding between 2-ABP and α-CD is different from that of 3- and 4-ABP, resulting in different molecular conformations and CCS, and the interaction modes of ABP with β-CD are similar to that with γ-CD, which are very consistent with the experimental observations. Finally, relative quantification of the method was performed, and satisfactory linearity with correlation coefficients (R2) greater than 0.99 was obtained. This method for isomer discrimination and conformation analysis possesses the advantages of simplicity, sensitivity, cost-effectiveness, and as such it may be widely applied in chemistry and pharmaceutical sciences.
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Affiliation(s)
- Fangling Wu
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China
- National Institute of Metrology, Beijing 100029, China
| | - Shutong Yang
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China
- National Institute of Metrology, Beijing 100029, China
| | - Xinhua Dai
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China
- National Institute of Metrology, Beijing 100029, China
| | - Liancheng Gu
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China
- National Institute of Metrology, Beijing 100029, China
| | - Fuxing Xu
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China
- National Institute of Metrology, Beijing 100029, China
| | - Xiang Fang
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China
- National Institute of Metrology, Beijing 100029, China
| | - Shaoning Yu
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China
- National Institute of Metrology, Beijing 100029, China
| | - Chuan-Fan Ding
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China
- National Institute of Metrology, Beijing 100029, China
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An insight into the vicarious nucleophilic substitution reaction of 2-nitro-5,10,15,20-tetraphenylporphyrin with p-chlorophenoxyacetonitrile: Synthesis and gas-phase fragmentation studies. ARAB J CHEM 2020. [DOI: 10.1016/j.arabjc.2020.04.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Malinowska M, Kozlowska M, Hryniewicka A, Morzycki JW. New olefin metathesis catalyst bearing N-mesitylimidazole and nitrate ligands – Synthesis, activity, and performance in aqueous media. J Organomet Chem 2019. [DOI: 10.1016/j.jorganchem.2019.06.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Domingues MRM, Domingues P, Neves MG, Tomé AC, Cavaleiro JA. Recent developments in the structural characterization of substituted meso-tetraarylporphyrins by electrospray tandem mass spectrometry. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424609000620] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
meso-tetraarylporphyrins with different substituents linked either to an aryl ring or to a β-pyrrolic position were studied by Electrospray (ESI) Tandem Mass Spectrometry (MS/MS). The electrospray mass spectra (ESI-MS) of meso-tetraarylporphyrins show the molecular ions and no significant fragmentation is noted. Structural information can be obtained by inducing fragmentation of the ions generated under ESI conditions. The product ions formed and registered in the tandem mass spectra (ESI-MS/MS) are characteristic of the chemical structure of the groups linked to the porphyrin and depend on their location. Also, the same functional group linked either to the aryl ring or to the β-pyrrolic position yields different product ions that confirm their position. Taking into consideration the Portugal-Spain special issue of the Journal of Porphyrins and Phthalocyanines, in this highlight we analyze the work done at the University of Aveiro related to the use of mass spectrometry in the structural characterization of meso-tetraarylporphyrins with carbohydrate, nitro and amino acid groups.
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Affiliation(s)
- M. Rosário M. Domingues
- Department of Chemistry, Mass Spectrometry Center, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Pedro Domingues
- Department of Chemistry, Mass Spectrometry Center, University of Aveiro, 3810-193 Aveiro, Portugal
| | | | - Augusto C. Tomé
- Department of Chemistry, QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal
| | - José A.S. Cavaleiro
- Department of Chemistry, QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal
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Nemykin VN, Rohde GT, Barrett CD, Hadt RG, Sabin JR, Reina G, Galloni P, Floris B. Long-Range Electronic Communication in Free-Base meso-Poly(Ferrocenyl)-Containing Porphyrins. Inorg Chem 2010; 49:7497-509. [DOI: 10.1021/ic101012a] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Victor N. Nemykin
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812
| | - Gregory T. Rohde
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812
| | - Christopher D. Barrett
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812
| | - Ryan G. Hadt
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812
| | - Jared R. Sabin
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812
| | - Giacomo Reina
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812
- Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma “Tor Vergata”, via della ricerca scientifica, 00133 Rome, Italy
| | - Pierluca Galloni
- Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma “Tor Vergata”, via della ricerca scientifica, 00133 Rome, Italy
| | - Barbara Floris
- Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma “Tor Vergata”, via della ricerca scientifica, 00133 Rome, Italy
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Samankumara LP, Zeller M, Krause JA, Brückner C. Syntheses, structures, modification, and optical properties of meso-tetraaryl-2,3-dimethoxychlorin, and two isomeric meso-tetraaryl-2,3,12,13-tetrahydroxybacteriochlorins. Org Biomol Chem 2010; 8:1951-65. [PMID: 20449503 DOI: 10.1039/b924539a] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Lalith P Samankumara
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, CT 06269-3060, USA
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Ryppa C, Niedzwiedzki D, Morozowich NL, Srikanth R, Zeller M, Frank HA, Brückner C. Stepwise conversion of two pyrrole moieties of octaethylporphyrin to pyridin-3-ones: synthesis, mass spectral, and photophysical properties of mono and bis(oxypyri)porphyrins. Chemistry 2009; 15:5749-62. [PMID: 19388039 PMCID: PMC3748135 DOI: 10.1002/chem.200900280] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Free-base octaethylporphyrin (OEP) was converted in two steps (beta,beta'-dihydroxylation and oxidative diol cleavage with concomitant aldol condensation) to the corresponding oxypyriporphyrin. This conversion was previously described to be applicable only to the Ni(II) complex of OEP. Modified diol cleavage conditions made this reaction sequence now applicable to free-base OEP. The single-crystal structure of the resulting free-base oxypyriporphyrin was determined, proving its near-perfect planarity. The reaction sequence can also be applied to oxypyriporphyrin itself, generating the unprecedented bacteriochlorin-type bis(oxypyri)porphyrin as two separable isomers. The ground-state (UV/Vis and fluorescence spectroscopies) and excited-state (transient triplet-triplet absorption, triplet lifetimes, and triplet EPR spectroscopy) photophysical properties of all chromophores are compared with those of OEP, chlorins, and oxochlorins. The pyridone-modified porphyrins possess unique spectroscopic signatures that distinguish them from regular porphyrins or chlorins. The presence of the pyridone moiety alters the ESI(+) collision-induced fragmentation properties of these oxypyriporphyrins only to a minor degree when compared with those of OEP or chlorins, confirming their stability.
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Affiliation(s)
- Claudia Ryppa
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, CT 06269-3060 (U.S.A.), Fax: (+1) 860 486 2743
| | - Dariusz Niedzwiedzki
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, CT 06269-3060 (U.S.A.), Fax: (+1) 860 486 2743
| | - Nicole L. Morozowich
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, CT 06269-3060 (U.S.A.), Fax: (+1) 860 486 2743
| | - Rapole Srikanth
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, CT 06269-3060 (U.S.A.), Fax: (+1) 860 486 2743
| | - Matthias Zeller
- Department of Chemistry, Youngstown State University, One University Plaza, Youngstown, OH 44555-3663 (U.S.A.)
| | - Harry A. Frank
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, CT 06269-3060 (U.S.A.), Fax: (+1) 860 486 2743
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, CT 06269-3060 (U.S.A.), Fax: (+1) 860 486 2743
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Barros AIRNA, Nunes FM, Barros C, Silva AMS, Domingues MRM. Structural characterization of nitrated 2'-hydroxychalcones by electrospray ionization tandem mass spectrometry. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2009; 15:605-616. [PMID: 19679941 DOI: 10.1255/ejms.1020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Isomeric 2'-hydroxychalcones bearing nitro and methoxy groups in different positions of their skeleton were analyzed by tandem mass spectrometry (MS/MS) with electrospray ionization (ESI), in positive mode. Collision-induced dissociation of the protonated molecules, [M + H](+), formed under electrospray conditions were studied and it was found that the product ion spectra of these chalcones presented different fragmentation patterns depending on the position of the substituents on the molecule. The product ion spectra (ESI- MS/MS) of the B ring ortho-nitro substituted 2'-hydroxychalcone and of the 4'-methoxychalcones showed loss of OH, 2OH and combined losses of OH and H(2)O. These fragment ions were absent in the spectra of the respective meta- and para isomers. The observed differences in the product ion spectra of these nitrochalcones allowed identification of the o-nitro derivatives. Distinction between the meta- and para derivatives was not achieved. Chalcones bearing 6'-methoxy substituents showed distinct fragmentation from the one observed for their isomers, 4'-methoxychalcones, since they present only one fragment ion, a typical ((0,alpha)A - H)(+) and, therefore, do not allow detailed structural information to be obtained, nor to differentiate between the o-, m- or p-nitro isomers. Overall, it was found that small changes in the substitution pattern of chalcones change their fragmentation considerably in the ESI-MS/MS, and that these features permit the differentiation of specific isomers of these 2'-hydroxynitrochalcones.
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Affiliation(s)
- Ana I R N A Barros
- Chemistry Department, University of Trás-os-Montes e Alto Douro, 5001-911 Vila Real, Portugal.
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9
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Silva EMP, Domingues P, Tomé JPC, Faustino MAF, Neves MGPMS, Tomé AC, Dauzonne D, Silva AMS, Cavaleiro JAS, Ferrer-Correia AJ, Domingues MRM. Electrospray tandem mass spectrometry of beta-nitroalkenyl meso-tetraphenylporphyrins. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2008; 14:49-59. [PMID: 18401045 DOI: 10.1255/ejms.908] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Beta-nitroalkenyl meso-tetraphenylporphyrins [beta-TPPCHC(NO(2))R)], as free-bases and Zn(II) complexes, were studied by electrospray mass spectrometry (ESI-MS). Under this ionisation condition the [M + H](+) ions are formed. The fragmentation pattern of the resulting [M + H](+) ions were studied by electrospray tandem mass spectrometry (ESI-MS/MS). The ESI-MS/MS of beta- nitroalkenylporphyrins, either as free-bases or as Zn(II) complexes, show several interesting features, distinct from the typical behaviour of nitro compounds. For the studied compounds, common main fragmentation patterns are observed, namely characteristic losses of NO(2), HNO(2), 2OH, RNO(2), RCNO, RCNO(2), RCH(2)NO(2), C(6)H(5) plus NO(2) and the formation of the protonated macrocycle, [TPP + H](+) or [ZnTPP + H](+). However, depending on the presence or absence of the metal and the nature of the R substituent, important differences are observed on the relative abundances of the ions formed by the same fragmentation pathway. The presence of bromine in the alkenyl group leads to a peculiar behaviour, since the main fragmentation pattern corresponds to the combined elimination of the bromine atom with the typical nitro group fragments. When R = Br, the loss of the nitro group occurs in low relative abundance (11-16%). However, when R = CH(3), the relative abundance of the ion due to the loss of HNO(2) changes drastically from 100%, observed for the free-base porphyrin, to 29% in the case of the Zn(II) complex. These variations of the relative abundance of the fragment corresponding to the loss of the nitro moiety (typically considered as a diagnostic fragment) can induce to an erroneous interpretation of their MS/MS spectra. Some fragmentations are observed only for the free-base porphyrins, namely the loss of CH(NO(2)R and HNO(2) plus C(2)H(2), while the loss of OH, H(2)O, OH plus H(2)O and RCCH plus H(2)O is observed only for the complexes. Unusual and unexpected fragmentations are also observed, namely the losses of RCNO, RCNO(2) and HNO(2) plus C(2)H(2). This work demonstrates that valuable structural information about the beta-nitroalkenyl substituents linked to meso- tetraarylporphyrins can be achieved using MS/MS. These results can also be useful for the interpretation of the mass spectra of other nitroalkenyl substituted compounds.
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Affiliation(s)
- Eduarda M P Silva
- Organic Chemistry Group, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
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Moolayil JT, George M, Srinivas R, Giblin D, Russell A, Gross ML. Protonated nitro group as a gas-phase electrophile: experimental and theoretical study of the cyclization of o-nitrodiphenyl ethers, amines, and sulfides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2007; 18:2204-2217. [PMID: 17977011 PMCID: PMC2744296 DOI: 10.1016/j.jasms.2007.09.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Revised: 09/26/2007] [Accepted: 09/26/2007] [Indexed: 05/25/2023]
Abstract
A novel gas-phase electrophilic cyclization, initiated by the protonation of a nitro group, occurs for 2-nitrophenyl phenyl ether and for the analogous sulfide and amine, leading to heterocyclic intermediates in each case. Subsequently, the cyclic intermediates dissociate via two pathways: (1) unusual step-wise eliminations of two OH radicals to afford heterocyclic cations, [phenoxazine - H](+), [phenothiazine - H](+), and [phenazine + H](+), and (2) expulsion of H(2)O, to yield a heterocyclic ketone, followed by loss of CO. The proposed structures of the gas-phase product ions and reaction mechanisms are supported by chemical substitution, deuterium labeling, accurate mass measurements at high mass resolving power, product-ion mass spectra obtained by tandem mass spectrometry, mass spectra of reference compounds, and molecular orbital calculations. Using a mass spectrometer as a reaction vessel, we demonstrate that, upon protonation, a nitro group becomes an electrophile and participates in cyclization reactions in the gas phase.
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Affiliation(s)
- Joseph T Moolayil
- Department of Chemistry, Sacred Heart College Thevara, Cochin, Kerala, India
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11
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Nemykin VN, Barrett CD, Hadt RG, Subbotin RI, Maximov AY, Polshin EV, Koposov AY. Mixed-valence states formation in conformationally flexible metal-free 5,10,15,20-tetraferrocenylporphyrin and 5,10-bisferrocenyl-15,20-bisphenylporphyrin. Dalton Trans 2007:3378-89. [PMID: 17664974 DOI: 10.1039/b703581k] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metal-free 5,10,15,20-tetraferrocenylporphyrin and 5,10-bisferrocenyl-15,20-bisphenylporphyrin have been prepared and characterized by UV-Vis, MCD, (1)H, (13)C, and variable-temperature NMR, APCI- and ESI-MS, and Mössbauer spectroscopy, while their redox properties were investigated using electrochemical (cyclic voltammetry and differential pulse voltammetry), spectroelectrochemical, and chemical oxidation approaches. The electronic structure calculations at Density Functional Theory level reveal that both compounds adopt saddle conformations and the HOMOs in both complexes are predominantly metal-centered, while the LUMOs predominantly consist of porphyrin pi* orbitals. In spite of the rotational freedom of ferrocenyl substituents at room temperature, both metal-free 5,10,15,20-tetraferrocenylporphyrin and 5,10-bisferrocenyl-15,20-bisphenylporphyrin are able to form mixed-valence states upon the successive ferrocene-based two- and one-electron oxidations, respectively, as confirmed by UV-Vis, MCD, Mössbauer, electro-, and spectroelectrochemical methods, and thus, the earlier suggested (Boyd et al. Chem. Commun., 1999, 637) requirements for the formation of mixed-valence states in ferrocene-containing porphyrins should be revised.
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Affiliation(s)
- Victor N Nemykin
- Department of Chemistry and Biochemistry, University of Minnesota Duluth, 1039 University Drive, Duluth, MN 55812, USA.
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Lau KSF, Sadilek M, Gouterman M, Khalil GE, Brückner C. Observation of phenyl-fused porphyrinoids during the ESI mass spectrometric analysis of meso-pentafluorophenyl-substituted porphyrin and corrole. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2006; 17:1306-14. [PMID: 16857382 DOI: 10.1016/j.jasms.2006.06.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Revised: 06/08/2006] [Accepted: 06/09/2006] [Indexed: 05/10/2023]
Abstract
The results of ESI(+) and ESI(-) mass spectrometry/mass spectrometry investigations of meso-tetrakisphenylporphyrin (TPP) and meso-trisphenylcorrole (TPC) in comparison with their meso-tetrakis(pentafluorophenyl)-substituted analogs T(F)PP and T(F)PC are reported. The fragmentation patterns of TPP and TPC show the expected loss of meso-aryl radicals. Analyzing the meso-pentafluorophenyl substituted analogs T(F)PP and T(F)PC, we found ESI(-) to be an excellent ionization mode. Rich and well-defined HF-elimination fragmentation patterns unique to the presence of meso-tetrafluorophenyl groups and evocative for the formation of fragments with direct covalent o-phenyl-to-beta-linkages are observed. A computation of the feasibility and relative energies of the resulting species corroborates the interpretation of the experimental findings. The computations indicate the presence of cooperative interactions between the linkages that direct the linkage formations to occur in a unidirectional fashion. MS/MS/MS experiments also provide indications for the regioselectivity of the fusions. Our observations further detail earlier reports of similar HF-eliminations and allow a generalization of the findings. The results presented may also point to strategies towards the bulk synthesis of novel porphyrinoid structures.
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Affiliation(s)
- Kimberly S F Lau
- Department of Chemistry, University of Washington, Seattle, Washington, USA
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Tai Y, Pei S, Wan J, Cao X, Pan Y. Fragmentation study of protonated chalcones by atmospheric pressure chemical ionization and tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:994-1000. [PMID: 16479556 DOI: 10.1002/rcm.2404] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Fragmentation mechanisms of protonated chalcone and its derivatives with different functional groups were investigated by atmospheric pressure chemical ionization with tandem mass spectrometry (MS/MS). The major fragmentation pathways were loss of the phenyl group from the A or B ring, combined with loss of CO. Losses of H(2)O and CO from the precursor ions of [M+H](+) are proposed to occur via rearrangements. Elimination of water from protonated chalcones was observed in all the title compounds to yield a stable ion but it was difficult to obtain skeletal fragmentation of a precursor ion. Loss of CO was found in the MS/MS spectra of all the compounds except the nitro-substituted chalcones. When the [M+H--CO](+) ion was fragmented in the MS/MS experiments, there were distinctive losses of 15 and 28 Da, as the methyl radical and ethylene, respectively. The ion at m/z 130, found only in the nitro-substituted chalcones, was assigned as C(9)H(6)O by Fourier transform ion cyclotron resonance (FTICR)-MS/MS; m/z 130 is a common fragment ion in the electron ionization (EI) spectra of chalcones. In order to more easily distinguish the constitutional isomers of these chalcones, breakdown curves were produced and these provided strong support in this study.
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Affiliation(s)
- Yuanpo Tai
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang Province 310027, China
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Silva EMP, Serra VV, Ribeiro AO, Tomé JPC, Domingues P, Faustino MAF, Neves MGPMS, Tomé AC, Cavaleiro JAS, Ferrer-Correia AJ, Iamamoto Y, Domingues MRM. Characterization of cationic glycoporphyrins by electrospray tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:3605-11. [PMID: 17091537 DOI: 10.1002/rcm.2766] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Novel cationic porphyrin derivatives having a galactose or a bis(isopropylidene)galactose unit linked directly to a pyridine or to an aminophenyl group were characterized by electrospray tandem mass spectrometry (ESI-MS/MS). The electrospray mass spectra (ESI-MS) show the M(+) ions, since these porphyrins are already monocharged in solution. The fragmentation of these ions under ESI-MS/MS conditions was studied and it was found that elimination of the sugar residue as a radical (-163 or -243 Da) is a common fragmentation pathway. Loss of the sugar unit as a neutral fragment (-162 or -242 Da) and cross-ring fragmentations typical of glyco-derivatives are also observed for the pyridinium glycoporphyrins, but they are absent in the case of ammonium glycoporphyrins. The cationic beta-pyridiniumvinyl porphyrins show an atypical fragmentation due to the cleavage of the C(5)-C(6) bond of the sugar unit. Overall, the different patterns of fragmentation observed in the ESI-MS/MS spectra of the sugar pyridinium porphyrins and of the sugar ammonium phenyl porphyrins can give important information about the type of spacer between the porphyrin and the sugar unit.
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Affiliation(s)
- Eduarda M P Silva
- Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
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Silva EMP, Domingues MRM, Barros C, Faustino MAF, Tomé JPC, Neves MGPMS, Tomé AC, Santana-Marques MG, Cavaleiro JAS, Ferrer-Correia AJ. Characterization of dinitroporphyrin zinc complexes by electrospray ionization tandem mass spectrometry. Unusual fragmentations of beta-(1,3-dinitroalkyl) porphyrins. JOURNAL OF MASS SPECTROMETRY : JMS 2005; 40:117-122. [PMID: 15643640 DOI: 10.1002/jms.789] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The zinc complexes of diaryl bis(p-nitrophenyl)porphyrins and beta-(1,3-dinitroalkyl)tetraphenylporphyrins were studied by electrospray ionization (ESI) tandem mass spectrometry (MS/MS). All porphyrins showed the protonated molecule under ESI conditions. The protonated molecules were induced to fragment and the corresponding ESI tandem mass spectra were analysed. Porphyrins with two p-nitrophenyl groups showed, as expected, characteristic fragmentations including either loss of one nitro group, as the major fragment of the tandem mass spectra, and loss of both nitro groups. In contrast, MS/MS of the beta-(1,3-dinitroalkyl)porphyrins provided interesting and unexpected results such as the absence (or in insignificant abundance) of the ions formed by loss of one nitro group. However, these porphyrins show an abundant fragment due to combined loss of the two nitro groups. Also, the typical beta-cleavage of the alkyl chain is not observed per se, only when combined with loss of HNO2 or *NO2. Instead, alpha-cleavage, with loss of the beta-pyrrolic substituent, is the most favourable process.
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Affiliation(s)
- E M P Silva
- Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
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Serra VV, Domingues MRM, Faustino MAF, Domingues P, Tomé JPC, Neves MGPMS, Tomé AC, Cavaleiro JAS, Ferrer-Correia AJ. Electrospray tandem mass spectrometry of new porphyrin amino acid conjugates. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:2569-80. [PMID: 16106376 DOI: 10.1002/rcm.2097] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Porphyrin amino acid conjugates with one or two porphyrin units were analyzed by electrospray ionization tandem mass spectrometry (ESI-MS/MS). The ESI-MS spectra of all the porphyrins studied, obtained in positive ion mode, show the presence of the corresponding protonated molecule [M+H]+; ESI-MS spectra of diporphyrinyl compounds also show the doubly charged ions [M+2H]2+. The fragmentations of these ions induced by collision with argon were studied (ESI-MS/MS). ESI-MS/MS gives detailed structural information about the amino acids associated with the porphyrin. Cleavage of the bonds in the vicinity of the porphyrin moiety and those involving the side chain of amino acid residues gives structural information about this type of association. A fragmentation common to all derivatives corresponds to the cleavage of the phenyl-CO bond. The expected cleavage of the amide bond, that links the porphyrin to the amino acid moiety, is a minor fragmentation, which in some cases is even absent. The MS/MS spectra of the monoporphyrinyl derivatives show product ions characteristic of the amino acid linked to the porphyrin; the fragmentation also indicates when the amino acids has a terminal carboxylic group or a terminal ester group. The fragmentations of the diporphyrinyl compounds occur mainly by the cleavage of the spacer, leading, in the case of the doubly charged ions, to predominantly mono-charged ions, indicating a preferential location of the two protons in separated porphyrinic units.
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Affiliation(s)
- V Vaz Serra
- Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
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Prasain JK, Patel R, Kirk M, Wilson L, Botting N, Darley-Usmar VM, Barnes S. Mass spectrometric methods for the analysis of chlorinated and nitrated isoflavonoids: a novel class of biological metabolites. JOURNAL OF MASS SPECTROMETRY : JMS 2003; 38:764-771. [PMID: 12898656 DOI: 10.1002/jms.492] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Electrospray ionization combined with tandem mass spectrometry was applied to a study of some representative chlorinated and nitrated isoflavones-potential metabolites of isoflavones in inflammatory cells. Upon collision-induced dissociation of deprotonated [M - H](-) ions of these compounds, a number of structurally characteristic product ions were produced. The product ion analysis of 3'- and 8-chlorodaidzein in the tandom mass spectra led to ready differentiation of these isomers. 3-Nitro derivatives of both genistein and daidzein have product ions due to the losses of HNO(2) and two OH groups. Chlorinated derivatives of isoflavones were detected in cell-based experiments and their structures were proposed by comparing the tandem mass spectra of their product ions with those of standards. This work provides a suitable analytical basis to aid the characterization of chlorinated and nitrated metabolites in studies in vivo and in vitro.
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Affiliation(s)
- Jeevan K Prasain
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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Domingues MRM, Marques MGOS, Alonso CMA, Neves MGPMS, Cavaleiro JAS, Ferrer-Correia AJ, Nemirovskiy OV, Gross ML. Unexpected fragmentation of beta-substituted meso-tetraphenylporphyrins induced by high-energy collisional activation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2002; 13:1427-1431. [PMID: 12484462 DOI: 10.1016/s1044-0305(02)00705-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The protonated molecules and radical cations of meso-tetraphenylporphyrins with beta-pyrrolic substituents, when formed by fast atom bombardment (FAB) and subjected to high-energy collisions, give rise to unexpected fragment ions. The reaction involves hydrogen migration from the ortho position of the phenyl ring to the a atom of the substituent, with formation of an intramolecular, six-membered ring. The process is analogous to condensed-phase cyclizations described for the same type of compounds. The fragmentation requires the presence of a double bond in the substituent group attached to the pyrrolic ring. A rearrangement process involving anchimeric assistance by the phenyl group (analogous to an ortho effect) is proposed for the formation of these ions.
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2001; 36:976-987. [PMID: 11523099 DOI: 10.1002/jms.95] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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