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Zou ZZ, Han MJ. Investigation of liquid chromatography-mass spectrometry analysis of a peptide aldehyde SJA6017 with identifying its hemiacetal, gem-diol, and enol ether. JOURNAL OF MASS SPECTROMETRY : JMS 2024; 59:e5022. [PMID: 38659190 DOI: 10.1002/jms.5022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 02/05/2024] [Accepted: 03/08/2024] [Indexed: 04/26/2024]
Abstract
The quantitative analysis of SJA6017, a peptide aldehyde inhibitor of calpain (Calpain Inhibitor VI), has encountered challenges in preclinical drug studies. The complex reverse-phase HPLC chromatographic behavior exhibits two peaks, each containing multiple species. An liquid chromatography-mass spectrometry (LC-MS/MS) study proposed an explanation for this phenomenon, caused by the amide aldehyde structure of SJA6017. Four chemical species corresponding to the two HPLC peaks have been identified as SJA6017 and its methyl hemiacetal, methyl enol ether, and gem-diol. In many instances of preclinical studies, methanol is favored as a substitute for DMSO. The hemiacetal is formed when the amide-activated peptide aldehyde reacts with methanol, which can then be further dehydrated in the mass spectrometer ion source under high temperature to form the methyl enol ether. The hemiacetal and gem-diol can also be decomposed to SJA6017 in the ion source. Additionally, the amide-activated peptide aldehyde can easily hydrate to the gem-diol of SJA6017 during sample incubation or sample preparation. The hemiacetal and gem-diol of SJA6017 are stable enough to have different retention times in the liquid chromatography, which explains why SJA6017 appears as two peaks, each containing multiple species. An LC-MS/MS tandem quadrupole mass spectrometer quantitative analysis method is proposed, enabling the analysis of these types of samples. This work serves as both an illustrative example and a cautionary note for mass analysis, sample incubations, and sample preparations involving compounds of peptide aldehyde, including similar aldehyde-containing metabolites, especially when methanol is present. This study provides the information needed to understand peptide aldehyde behavior at various steps of preclinical in vitro studies in the presence of methanol. It has assisted in the development of the SJA6017 bioanalysis method and will also aid in the development of bioanalysis methods for similar peptide aldehydes.
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Affiliation(s)
- Zhiyang Zack Zou
- Department of DMPK, Bioanalysis & Tox, Sundia Meditech Co., Ltd, Shanghai, China
| | - Ming-Jie Han
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, Airport Economic Area, Tianjin, China
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Gajjela R, Kandula RR, Kuppusamy P, Nimje RY, Gupta A, Bagadi M, Mathur A. Mass spectrometric-based investigation of differentially protected azatryptophan derivatives using Orbitrap mass spectrometry: Differentiation of positional isomers under protonation and alkali-cationization conditions. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2022; 36:e9239. [PMID: 34904316 DOI: 10.1002/rcm.9239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 06/14/2023]
Abstract
RATIONALE Differentiation and structural characterization of positional isomers of differentially protected azatryptophan derivatives using electrospray ionization high-resolution tandem mass spectrometry (ESI-HRMS/MS) is important from the perspective of drug discovery research. Also, these derivatives can be used as building blocks for the synthesis of various biologically active compounds and have attracted significant attention in the field of modern drug discovery, especially peptide-based drugs, protein folding and protein-protein interactions because of their interesting spectral properties. METHODS ESI-HRMS/MS in positive ionization mode was used to differentiate and characterize positional isomers of protected azatryptophan derivatives. RESULTS ESI-HRMS/MS of [M + H]+ and [M + Na]+ ions of positional isomers of differentially protected azatryptophan derivatives display distinct fragmentation patterns. The MS/MS of [M + H]+ ion of isomer 1 showed an additional ion at m/z 358.0846 ([M + H-Boc-C14 H10 -HF]+ ) which was not present for 4. The fragment ion at m/z 332.0857 was observed for 1 and not for 4 which would be formed by the expulsion of butyloxycarbonyl (Boc) and fluorenylmethyloxycarbonyl (Fmoc) groups. Moreover, the ions 422.0812 and 378.0912 are found to be relatively more abundant for isomer 4 which could be probably attributed to the formation of stable ions. Similarly, other positional isomers exhibited distinct fragmentation from one another. CONCLUSIONS The present study demonstrates that ESI-HRMS/MS can be used for differentiation and structural characterization of positional isomers of protected azatryptophan derivatives. The MS/MS of [M + H]+ and [M + Na]+ ions of these positional isomers displayed differences in their fragmentation behaviour. The impact of different substitutions at different positions (1 and 6) of protected azatryptophan derivatives (1-6) on their fragmentation behaviour was also investigated in detail. Also, the nitrogen atom at different positions in the pyrrolopyridine ring led to different fragmentation patterns.
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Affiliation(s)
- Raju Gajjela
- Discovery Analytical Sciences, Biocon Bristol Myers Squibb Research & Development Center (BBRC), Bangalore, India
| | - Ravikanth Reddy Kandula
- Discovery Analytical Sciences, Biocon Bristol Myers Squibb Research & Development Center (BBRC), Bangalore, India
| | - Prakasam Kuppusamy
- Department of Discovery Synthesis, Biocon Bristol Myers Squibb Research & Development Center (BBRC), Bangalore, India
| | - Roshan Y Nimje
- Department of Discovery Synthesis, Biocon Bristol Myers Squibb Research & Development Center (BBRC), Bangalore, India
| | - Anuradha Gupta
- Department of Discovery Synthesis, Biocon Bristol Myers Squibb Research & Development Center (BBRC), Bangalore, India
| | - Muralidhararao Bagadi
- Discovery Analytical Sciences, Biocon Bristol Myers Squibb Research & Development Center (BBRC), Bangalore, India
| | - Arvind Mathur
- Small Molecule Drug Discovery, Bristol Myers Squibb Research and Development, Princeton, New Jersey, USA
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Wang R, Zhao Z, Zhang H, Sheng C, Wang Y, Jiang K. Formation of the exceptional [M - H] + cation in atmospheric pressure ionization mass spectrometry analysis of 2-(diphenylsilyl) cyclopropanecarboxylate esters. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34:e8866. [PMID: 32559337 DOI: 10.1002/rcm.8866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE In general, ionization of analytes in atmospheric pressure ionization mass spectrometry (API-MS) in positive ion mode results in the formation of protonated molecules ([M + H]+ ) and/or cationized molecules (e.g., [M + Na]+ ). The formation of specific [M - H]+ cations in the API process is of significant interest for further investigation. METHODS The ionization processes of 2-(diphenylsilyl)-1-phenyl-cyclopropanecarboxylate esters were investigated using electrospray ionization (ESI)-MS and atmospheric pressure chemical ionization-MS in positive ion mode. Theoretical calculations were carried out with the Gaussian 03 program using the density functional theory (DFT) method at the B3LYP/6-311 + G(2d,p) level. RESULTS The anomalous [M - H]+ ion and the regular [M + Na]+ ion were both observed using ESI-MS. Interestingly, no [M + H]+ ion was obtained in the ESI-MS analysis, and acidification of the ESI solvent accelerated the formation of [M - H]+ rather than [M + H]+ ion. DFT calculations for the typical methyl 2-(diphenylsilyl)-1-phenyl-cyclopropanecarboxylate (1) indicated that the [1 + H]+ ion can thermodynamically and kinetically undergo facile H2 elimination to generate [1 - H]+ . CONCLUSIONS The favorable formation of [M - H]+ ions in these compounds is attributed to the unique diphenylhydrosilyl group in their structure. The [M + H]+ ion formed easily underwent H2 elimination to produce the [1 - H]+ ion in the API source, and thus, acidification of the ESI solvent apparently accelerates the formation of the [1 - H]+ ion.
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Affiliation(s)
- Ruoqian Wang
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Zhiyuan Zhao
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Huarong Zhang
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Chunqi Sheng
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Yan Wang
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Kezhi Jiang
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
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Damont A, Olivier MF, Warnet A, Lyan B, Pujos-Guillot E, Jamin EL, Debrauwer L, Bernillon S, Junot C, Tabet JC, Fenaille F. Proposal for a chemically consistent way to annotate ions arising from the analysis of reference compounds under ESI conditions: A prerequisite to proper mass spectral database constitution in metabolomics. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:567-582. [PMID: 31083780 DOI: 10.1002/jms.4372] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 04/25/2019] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
Nowadays, high-resolution mass spectrometry is widely used for metabolomic studies. Thanks to its high sensitivity, it enables the detection of a large range of metabolites. In metabolomics, the continuous quest for a metabolite identification as complete and accurate as possible has led during the last decade to an ever increasing development of public MS databases (including LC-MS data) concomitantly with bioinformatic tool expansion. To facilitate the annotation process of MS profiles obtained from biological samples, but also to ease data sharing, exchange, and exploitation, the standardization and harmonization of the way to describe and annotate mass spectra seemed crucial to us. Indeed, under electrospray (ESI) conditions, a single metabolite does not produce a unique ion corresponding to its protonated or deprotonated form but could lead to a complex mixture of signals. These MS signals result from the existence of different natural isotopologues of the same compound and also to the potential formation of adduct ions, homomultimeric and heteromultimeric ions, fragment ions resulting from "prompt" in-source dissociations. As a joint reflection process within the French Infrastructure for Metabolomics and Fluxomics (MetaboHUB) and with the purpose of developing a robust and exchangeable annotated MS database made from pure reference compounds (chemical standards) analysis, it appeared to us that giving the metabolomics community some clues to standardize and unambiguously annotate each MS feature was a prerequisite to data entry and further efficient querying of the mass spectral database. The use of a harmonized notation is also mandatory for interlaboratory MS data exchange. Additionally, thorough description of the variety of MS signals arising from the analysis of a unique metabolite might provide greater confidence on its annotation.
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Affiliation(s)
- Annelaure Damont
- Service de Pharmacologie et Immuno-Analyse (SPI), Laboratoire d'Etude du Métabolisme des Médicaments, CEA, INRA, Université Paris Saclay, MetaboHUB, F-91191, Gif-sur-Yvette, France
| | - Marie-Françoise Olivier
- Service de Pharmacologie et Immuno-Analyse (SPI), Laboratoire d'Etude du Métabolisme des Médicaments, CEA, INRA, Université Paris Saclay, MetaboHUB, F-91191, Gif-sur-Yvette, France
| | - Anna Warnet
- Service de Pharmacologie et Immuno-Analyse (SPI), Laboratoire d'Etude du Métabolisme des Médicaments, CEA, INRA, Université Paris Saclay, MetaboHUB, F-91191, Gif-sur-Yvette, France
| | - Bernard Lyan
- Plateforme d'Exploration du Métabolisme, MetaboHUB Clermont, Université Clermont Auvergne, INRA, UNH, F-63000, Clermont-Ferrand, France
| | - Estelle Pujos-Guillot
- Plateforme d'Exploration du Métabolisme, MetaboHUB Clermont, Université Clermont Auvergne, INRA, UNH, F-63000, Clermont-Ferrand, France
| | - Emilien L Jamin
- Toxalim (Research Centre in Food Toxicology), Metatoul-AXIOM platform, Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, F-31027, Toulouse, France
| | - Laurent Debrauwer
- Toxalim (Research Centre in Food Toxicology), Metatoul-AXIOM platform, Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, F-31027, Toulouse, France
| | - Stéphane Bernillon
- UMR1332 Biologie du Fruit et Pathologie, INRA, Univ. Bordeaux, Plateforme Métabolome du Centre de Génomique Fonctionnelle Bordeaux-MetaboHUB, IBVM, Centre INRA de Nouvelle Aquitaine-Bordeaux, 71 av Edouard Bourlaux, 33140, Villenave d'Ornon, France
| | - Christophe Junot
- Service de Pharmacologie et Immuno-Analyse (SPI), Laboratoire d'Etude du Métabolisme des Médicaments, CEA, INRA, Université Paris Saclay, MetaboHUB, F-91191, Gif-sur-Yvette, France
| | - Jean-Claude Tabet
- Service de Pharmacologie et Immuno-Analyse (SPI), Laboratoire d'Etude du Métabolisme des Médicaments, CEA, INRA, Université Paris Saclay, MetaboHUB, F-91191, Gif-sur-Yvette, France
- CNRS, Institut Parisien de Chimie Moléculaire, IPCM, Sorbonne Université, 75005, Paris, France
| | - François Fenaille
- Service de Pharmacologie et Immuno-Analyse (SPI), Laboratoire d'Etude du Métabolisme des Médicaments, CEA, INRA, Université Paris Saclay, MetaboHUB, F-91191, Gif-sur-Yvette, France
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Xiao HM, Wang X, Yang X, Zheng F, Feng YQ. Hydralazine derivative of aldehyde: A new type of [M - H] + ion formed in electrospray ionization mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:239-249. [PMID: 30650224 DOI: 10.1002/jms.4330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 12/19/2018] [Accepted: 01/08/2019] [Indexed: 06/09/2023]
Abstract
Hydralazine has been widely employed in the development of drugs, derivatization reagents, and ligands. In the present work, we reported a new type of dehydrogenated ion [M - H]+ that was produced from the hydralazine derivative of hexanal in electrospray ionization mass spectrometry (ESI-MS). The formation of [M - H]+ ions in the ESI-MS was found to be independent on the mobile phase composition of the liquid chromatography and ESI source parameters. A series of hydralazine derivatives of aldehyde were investigated to confirm this phenomenon. The results showed that hydralazine derivatives of aldehydes that contained an sp3 hybridization carbon with a hydrogen at the α-position of aldehydes could form the unexpected [M - H]+ ions, whereas hydralazine derivative of acetone could only generate [M + H]+ ion in the ESI-MS. We proposed the possible formation mechanism of [M - H]+ ion for the hydralazine derivatives of aldehydes: the [M - H]+ ion was possibly formed by the loss a hydrogen molecule (H2 ) from the protonated ion [M + H]+ . The results obtained from density functional theory (DFT) calculations supported this proposed formation mechanism of [M - H]+ ion.
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Affiliation(s)
- Hua-Ming Xiao
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan, 430072, People's Republic of China
| | - Xian Wang
- Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, College of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan, Hubei, 430074, People's Republic of China
| | - Xing Yang
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Feng Zheng
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan, 430072, People's Republic of China
| | - Yu-Qi Feng
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan, 430072, People's Republic of China
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Potęga A, Garwolińska D, Nowicka AM, Fau M, Kot-Wasik A, Mazerska Z. Phase I and phase II metabolism simulation of antitumor-active 2-hydroxyacridinone with electrochemistry coupled on-line with mass spectrometry. Xenobiotica 2019; 49:922-934. [PMID: 30301406 DOI: 10.1080/00498254.2018.1524946] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Here, we report the metabolic profile and the results of associated metabolic studies of 2-hydroxy-acridinone (2-OH-AC), the reference compound for antitumor-active imidazo- and triazoloacridinones. Electrochemistry coupled with mass spectrometry was applied to simulate the general oxidative metabolism of 2-OH-AC for the first time. The reactivity of 2-OH-AC products to biomolecules was also examined. The usefulness of the electrochemistry for studying the reactive drug metabolite trapping (conjugation reactions) was evaluated by the comparison with conventional electrochemical (controlled-potential electrolysis) and enzymatic (microsomal incubation) approaches. 2-OH-AC oxidation products were generated in an electrochemical thin-layer cell. Their tentative structures were assigned based on tandem mass spectrometry in combination with accurate mass measurements. Moreover, the electrochemical conversion of 2-OH-AC in the presence of reduced glutathione and/or N-acetylcysteine unveiled the formation of reactive metabolite-nucleophilic trapping agent conjugates (m/z 517 and m/z 373, respectively) through the thiol group. This glutathione S-conjugate was also identified after electrolysis experiment as well as was detected in liver microsomes. Summing up, the present work illustrates that the electrochemical simulation of metabolic reactions successfully supports the results of classical electrochemical and enzymatic studies. Therefore, it can be a useful tool for synthesis of drug metabolites, including reactive metabolites.
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Affiliation(s)
- Agnieszka Potęga
- a Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry , Gdańsk University of Technology , Gdańsk , Poland
| | - Dorota Garwolińska
- b Department of Analytical Chemistry, Faculty of Chemistry , Gdańsk University of Technology , Gdańsk , Poland
| | - Anna M Nowicka
- c Laboratory of Theory and Applications of Electrodes, Faculty of Chemistry , University of Warsaw , Warsaw , Poland
| | - Michał Fau
- c Laboratory of Theory and Applications of Electrodes, Faculty of Chemistry , University of Warsaw , Warsaw , Poland
| | - Agata Kot-Wasik
- b Department of Analytical Chemistry, Faculty of Chemistry , Gdańsk University of Technology , Gdańsk , Poland
| | - Zofia Mazerska
- a Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry , Gdańsk University of Technology , Gdańsk , Poland
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7
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Liu Z, Shao Y, Zhu G, Wang X, Chai Y, Wang L. Gas phase reaction between chromones and solvent in an electrospray ionization source. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:66-72. [PMID: 30381853 DOI: 10.1002/jms.4305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/21/2018] [Accepted: 10/22/2018] [Indexed: 05/18/2023]
Abstract
Chromones were measured by using electrospray ionization mass spectrometry in negative mode. Interestingly, in addition to the deprotonated ion ([M - H]- ), unexpected [M + 17]- and [M + 31]- ions were observed in high intensity when water and methanol were used as the solvent. Chromones with different substitutes were tested. Compared with the deprotonated ion, [M + 17]- and [M + 31]- ions were observed with higher abundances when the C-3 site of chromones was substituted by electron withdrawing groups. Based on high performance liquid chromatography-mass spectrometry (LC-MS), deuterium-labeling and collisional-induced dissociation experiments, a covalent gas-phase nucleophilic addition reaction between chromone and water, and the formation of a noncovalent complex between chromone and methanol were proposed as the mechanism for the observed [M + 17]- and [M + 31]- ions, respectively. Understanding and using these unique gas phase reactions can avoid misannotation when analyzing chromones and their metabolites.
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Affiliation(s)
- Zhen Liu
- Department of Chemistry and Chemical Engineering, Beijing University of Technology, Beijing, China
| | - Yunlong Shao
- Department of Chemistry and Chemical Engineering, Beijing University of Technology, Beijing, China
| | - Guizhen Zhu
- Department of Chemistry and Chemical Engineering, Beijing University of Technology, Beijing, China
| | - Xiayan Wang
- Department of Chemistry and Chemical Engineering, Beijing University of Technology, Beijing, China
| | - Yunfeng Chai
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Lin Wang
- Department of Chemistry and Chemical Engineering, Beijing University of Technology, Beijing, China
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El-Maghrabey MH, Nakatani T, Kishikawa N, Kuroda N. Aromatic aldehydes as selective fluorogenic derivatizing agents for α‐dicarbonyl compounds. Application to HPLC analysis of some advanced glycation end products and oxidative stress biomarkers in human serum. J Pharm Biomed Anal 2018; 158:38-46. [DOI: 10.1016/j.jpba.2018.05.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/09/2018] [Accepted: 05/10/2018] [Indexed: 10/16/2022]
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Fang L, Dong C, Guo C, Xu J, Liu Q, Qu Z, Jiang K. Two competing ionization processes in ESI-MS analysis of N-(1,3-diphenylallyl)benzenamines: formation of the unusual [M-H] + ion versus the regular [M+H] + ion. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2018; 24:251-260. [PMID: 29232977 DOI: 10.1177/1469066717717228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A series of N-(1,3-diphenylallyl)benzenamine derivatives (M) were investigated by electrospray ionization mass spectrometry in the positive-ion mode. Both the anomalous [M-H]+ and the regular [M+H]+ were observed in the ESI mass spectra. The occurrence of [M-H]+ has been supported by accurate mass spectrometry, liquid chromatography mass spectrometry, and tandem mass spectrometry analysis. Calculation results indicated that formation of [M-H]+ is attributed to the ion-molecule reaction of M with the protonated ESI solvent molecule (e.g. CH3OH2+) via hydride abstraction from a tertiary Csp3-H. The competing ionization processes leading to [M-H]+ or [M+H]+ were significantly affected by the concentration of formic acid in the electrospray ionization solvent and the proton affinity of the N atom.
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Affiliation(s)
- Liwen Fang
- 1 Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Cheng Dong
- 1 Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Cheng Guo
- 2 Cancer Institute, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jianxing Xu
- 1 Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Qiaoling Liu
- 1 Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Zhirong Qu
- 1 Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
| | - Kezhi Jiang
- 1 Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, China
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Chai Y, Chen H, Liu X, Lu C. Degradation of the Neonicotinoid Pesticides in the Atmospheric Pressure Ionization Source. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:373-381. [PMID: 29260456 DOI: 10.1007/s13361-017-1832-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 10/01/2017] [Accepted: 10/01/2017] [Indexed: 05/21/2023]
Abstract
During the analysis of neonicotinoid pesticide standards (thiamethoxam, clothianidin, imidacloprid, acetamiprid, and thiacloprid) by mass spectrometry, the degradation of these pesticides (M-C=N-R is degraded into M-C=O, M is the skeleton moiety, and R is NO2 or CN) was observed in the atmospheric pressure ionization interfaces (ESI and APCI). In APCI, the degradation of all the five neonicotinoid pesticides studied took place, and the primary mechanism was in-source ion/molecule reaction, in which a molecule of water (confirmed by use of H218O) attacked the carbon of the imine group accompanying with loss of NH2R (R=NO2, CN). For the nitroguanidine neonicotinoid pesticides (R=NO2, including thiamethoxam, clothianidin, and imidacloprid), higher auxiliary gas heater temperature also contributed to their degradation in APCI due to in-source pyrolysis. The degradation of the five neonicotinoid pesticides studied in ESI was not significant. In ESI, only the nitroguanidine neonicotinoid pesticides could generate the degradation products through in-source fragmentation mechanism. The degradation of cyanoamidine neonicotinoid pesticides (R=CN, including acetamiprid and thiacloprid) in ESI was not observed. The degradation of neonicotinoid pesticides in the ion source of mass spectrometer renders some adverse consequences, such as difficulty interpreting the full-scan mass spectrum, reducing the sensitivity and accuracy of quantitative analysis, and misleading whether these pesticides have degraded in the real samples. Therefore, a clear understanding of these unusual degradation reactions should facilitate the analysis of neonicotinoid pesticides by atmospheric pressure ionization mass spectrometry. Graphical Abstract.
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Affiliation(s)
- Yunfeng Chai
- Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China
- Laboratory of Quality and Safety Risk Assessment for Tea (Hangzhou), Ministry of Agriculture, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China
| | - Hongping Chen
- Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China
- Laboratory of Quality and Safety Risk Assessment for Tea (Hangzhou), Ministry of Agriculture, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China
| | - Xin Liu
- Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China.
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China.
- Laboratory of Quality and Safety Risk Assessment for Tea (Hangzhou), Ministry of Agriculture, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China.
| | - Chengyin Lu
- Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China.
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China.
- Laboratory of Quality and Safety Risk Assessment for Tea (Hangzhou), Ministry of Agriculture, 9 South Meiling Road, Hangzhou, 310008, People's Republic of China.
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Burton C, Shi H, Ma Y. Development of a high-performance liquid chromatography – Tandem mass spectrometry urinary pterinomics workflow. Anal Chim Acta 2016; 927:72-81. [DOI: 10.1016/j.aca.2016.05.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 05/01/2016] [Accepted: 05/02/2016] [Indexed: 10/21/2022]
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12
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Zhang X, Jiang K, Zou J, Li Z. Two competing ionization processes in electrospray mass spectrometry of indolyl benzo[b]carbazoles: formation of M⁺• versus [M + H]⁺. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2015; 29:263-268. [PMID: 26411624 DOI: 10.1002/rcm.7103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 11/17/2014] [Indexed: 06/05/2023]
Abstract
RATIONALE Ionization in electrospray ionization mass spectrometry (ESI-MS) mainly occurs as a result of acid-base reactions or coordination with metal cations. Formation of the radical cation M(+•) in the ESI process has attracted our interest to perform further investigation. METHODS A series of indolyl benzo[b]carbazoles were investigated using a quadrupole ion trap mass spectrometer equipped with an ESI source or an atmospheric pressure chemical ionization (APCI) source in the positive-ion mode. Theoretical calculations were performed using the density functional theory (DFT) method at the B3LYP/6-31G(d) level. RESULTS Both the radical ion M(+•) and the protonated molecule [M + H](+) were obtained by ESI-MS analysis of indolyl benzo[b]carbazoles, while only [M + H](+) was observed in the APCI-MS analysis. The relative intensities of M(+•) and [M + H](+) were significantly affected by several ESI operating parameters and the nature of the substituents. CONCLUSIONS Formation of M(+•) and [M + H](+) was rationalized as two competing ionization processes in the ESI-MS analysis of indolyl benzo[b]carbazoles.
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Affiliation(s)
- Xiaoping Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, 311121, China
| | - Kezhi Jiang
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, 311121, China
| | - Jingfeng Zou
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, 311121, China
| | - Zuguang Li
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
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Jiang K, Zhang X, Bai X, Lv H, Li Z, Lee MR. Observation of the intermediates of in-source aldolization reaction in electrospray ionization mass spectrometry analysis of heteroaromatic aldehydes. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2015; 21:51-57. [PMID: 25906035 DOI: 10.1255/ejms.1307] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Electrospray ionization mass spectrometry (ESI-MS) analyses of 2-(1,2,4-triazole-1-yl)-6-methyl-3- quinolinecarboxaldehyde were carried out by using an ion trap mass spectrometer in a positive-ion mode. Interestingly, several unusual [M + 15](+), [M + 33](+), and [M + 47](+) ions were observed with a high abundance in the ESI-MS spectrum when methanol was used as the ESI solvent. However, only the protonated molecule was obtained with acetonitrile as the ESI solvent. These unusual ions have been proposed as the intermediates of an aldolization reaction occurring in the ESI source, which have been validated by a tandem mass spectrometry experiment, high-performance liquid chromatography/mass spectrometry analysis, and theoretical calculations. A full understanding of this reaction can contribute to the avoidance of analysis errors in the ESI-MS analysis of unknown heteroaromatic aldehydes.
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Affiliation(s)
- Kezhi Jiang
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, 311121, China.
| | - Xiaoping Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China. Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, 311121, China.
| | - Xingfeng Bai
- Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, 311121, China
| | - Huiqing Lv
- College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310053, China.
| | - Zuguang Li
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China.
| | - Maw-Rong Lee
- Department of Chemistry, National Chung-Hsing University, Taichung, 40227, Taiwan.
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Neta P, Simón-Manso Y, Liang Y, Stein SE. Loss of H2 and CO from protonated aldehydes in electrospray ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2014; 28:1871-1882. [PMID: 25088131 DOI: 10.1002/rcm.6968] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/15/2014] [Accepted: 06/23/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Electrospray ionization mass spectrometry (ESI-MS) of many protonated aldehydes shows loss of CO as a major fragmentation pathway. However, we find that certain aldehydes undergo loss of H2 followed by reaction with water in the collision cell. This complicates interpretation of tandem mass (MS/MS) spectra and affects multiple reaction monitoring (MRM) results. METHODS 3-Formylchromone and other aldehydes were dissolved in acetonitrile/water/formic acid and studied by ESI-MS to record their MS(2) and MS(n) spectra in several mass spectrometers (QqQ, QTOF, ion trap (IT), and Orbitrap HCD). Certain product ions were found to react with water and the rate of reaction was determined in the IT instrument using zero collision energy and variable activation times. Theoretical calculations were performed to help with the interpretation of the fragmentation mechanism. RESULTS Protonated 3-formylchromones and 3-formylcoumarins undergo loss of H2 as a major fragmentation route to yield a ketene cation, which reacts with water to form a protonated carboxylic acid. In general, protonated aldehydes which contain a vicinal group that forms a hydrogen bridge with the formyl group undergo significant loss of H2. Subsequent losses of CO and C3O are also observed. Theoretical calculations suggest mechanistic details for these losses. CONCLUSIONS Loss of H2 is a major fragmentation channel for protonated 3-formychromones and certain other aldehydes and it is followed by reaction with water to produce a protonated carboxylic acid, which undergoes subsequent fragmentation. This presents a problem for reference libraries and raises concerns about MRM results.
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Affiliation(s)
- Pedatsur Neta
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
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Hongo Y, Nakamura T, Takahashi S, Motoyama T, Hayashi T, Hirota H, Osada H, Koshino H. Detection of oxygen addition peaks for terpendole E and related indole-diterpene alkaloids in a positive-mode ESI-MS. JOURNAL OF MASS SPECTROMETRY : JMS 2014; 49:537-542. [PMID: 24913406 PMCID: PMC4207197 DOI: 10.1002/jms.3360] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 03/05/2014] [Accepted: 03/10/2014] [Indexed: 05/29/2023]
Abstract
This report describes that a regular positive electrospray ionization mass spectrometry (MS) analysis of terpendoles often causes unexpected oxygen additions to form [M + H + O](+) and [M + H + 2O](+), which might be a troublesome in the characterization of new natural analogues. The intensities of [M + H + O](+) and [M + H + 2O](+) among terpendoles were unpredictable and fluctuated largely. Simple electrochemical oxidation in electrospray ionization was insufficient to explain the phenomenon. So we studied factors to form [M + H + O](+) and [M + H + 2O](+) using terpendole E and natural terpendoles together with some model indole alkaloids. Similar oxygen addition was observed for 1,2,3,4-tetrahydrocyclopent[b]indole, which is corresponding to the substructure of terpendole E. In tandem MS experiments, a major fragment ion at m/z 130 from protonated terpendole E was assigned to the substructure containing indole. When the [M + H + O](+) was selected as a precursor ion, the ion shifted to m/z 146. The same 16 Da shift of fragments was also observed for 1,2,3,4-tetrahydrocyclopent[b]indole, indicating that the oxygen addition of terpendole E took place at the indole portion. However, the oxygen addition was absent for some terpendoles, even whose structure resembles terpendole E. The breakdown curves characterized the tandem MS features of terpendoles. Preferential dissociation into m/z 130 suggested the protonation tendency at the indole site. Terpendoles that are preferentially protonated at indole tend to form oxygen addition peaks, suggesting that the protonation feature contributes to the oxygen additions in some degrees.
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Affiliation(s)
| | | | | | | | | | | | - Hiroyuki Osada
- Antibiotics Laboratory, RIKENWako, Japan
- Center for Sustainable Resource Science, RIKENWako, Japan
| | - Hiroyuki Koshino
- Global Research Cluster, RIKENWako, Japan
- Synthetic Organic Chemistry Laboratory, RIKENWako, Japan
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Lu Z, Chai Y, Guo C, Sun C, Pan Y. H2O loss in the fragmentation of deprotonated N-o-tolylamides in tandem mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2013; 48:1010-1014. [PMID: 24078241 DOI: 10.1002/jms.3257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Revised: 07/13/2013] [Accepted: 07/16/2013] [Indexed: 06/02/2023]
Affiliation(s)
- Zhihua Lu
- Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
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