Simultaneous measurement of metabolic stability and metabolite identification of 7‐methoxymethylthiazolo[3,2‐a]pyrimidin‐5‐one derivatives in human liver microsomes using liquid chromatography/ion‐trap mass spectrometry

Ethirajulu, Kantharaj; Ehmer, Peter B.; Tuytelaars, An; Vlaslaer, Anne Van; Mackie, Claire; Gilissen, RMCA mammalogy - Emmanuel

doi:10.1002/rcm.1891

Cited by 13 publications

(7 citation statements)

References 11 publications

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“…This ionization technique has promoted a great boom not only in proteomics but also in drug metabolite identification, because it enables the soft ionization of phase II metabolites, providing reliable information on the MWs of these conjugates, unlike other ionization techniques. For parent drug and phase I metabolites with a lower polarity, APCI and APPI may provide better ionization efficiency and sensitivity [ 81 , 82 ]. A better tolerance to salts and matrix effects has been reported for APCI [ 83 ] and APPI [ 84 ] in comparison with ESI.…”

Section: Introductionmentioning

confidence: 99%

High-performance liquid chromatography–tandem mass spectrometry in the identification and determination of phase I and phase II drug metabolites

2008

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Applications of tandem mass spectrometry (MS/ MS) techniques coupled with high-performance liquid chromatography (HPLC) in the identification and determination of phase I and phase II drug metabolites are reviewed with an emphasis on recent papers published predominantly within the last 6 years (2002)(2003)(2004)(2005)(2006)(2007) reporting the employment of atmospheric pressure ionization techniques as the most promising approach for a sensitive detection, positive identification and quantitation of metabolites in complex biological matrices. This review is devoted to in vitro and in vivo drug biotransformation in humans and animals. The first step preceding an HPLC-MS bioanalysis consists in the choice of suitable sample preparation procedures (biomatrix sampling, homogenization, internal standard addition, deproteination, centrifugation, extraction). The subsequent step is the right optimization of chromatographic conditions providing the required separation selectivity, analysis time and also good compatibility with the MS detection. This is usually not accessible without the employment of the parent drug and synthesized or isolated chemical standards of expected phase I and sometimes also phase II metabolites. The incorporation of additional detectors (photodiode-array UV, fluorescence, polarimetric and others) between the HPLC and MS instruments can result in valuable analytical information supplementing MS results. The relation among the structural changes caused by metabolic reactions and corresponding shifts in the retention behavior in reversed-phase systems is discussed as supporting information for identification of the metabolite. The first and basic step in the interpretation of mass spectra is always the molecular weight (MW) determination based on the presence of protonated molecules [M+H] + and sometimes adducts with ammonium or alkali-metal ions, observed in the positive-ion full-scan mass spectra. The MW determination can be confirmed by the [M-H] -ion for metabolites providing a signal in negative-ion mass spectra. MS/MS is a worthy tool for further structural characterization because of the occurrence of characteristic fragment ions, either MS n analysis for studying the fragmentation patterns using trap-based analyzers or high mass accuracy measurements for elemental composition determination using time of flight based or Fourier transform mass analyzers. The correlation between typical functional groups found in phase I and phase II drug metabolites and corresponding neutral losses is generalized and illustrated for selected examples. The choice of a suitable ionization technique and polarity mode in relation to the metabolite structure is discussed as well.

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Section: Introductionmentioning

confidence: 99%

High-performance liquid chromatography–tandem mass spectrometry in the identification and determination of phase I and phase II drug metabolites

2008

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“…However, the quantitation capability of this approach was somewhat worse than that of triple‐quadrupole under SRM mode. Kantharaj et al 10, 11 used a 3‐D ion trap to perform simultaneous metabolic stability measurement and metabolite identification within the same injection cycle. The authors used full‐scan data followed by data‐dependent MS/MS scans to confirm the identities of metabolites, and used extracted full‐scan data to perform the quantitation of parent compounds.…”

Section: Introductionmentioning

confidence: 99%

A novel approach to perform metabolite screening during the quantitative LC–MS/MS analyses of in vitro metabolic stability samples using a hybrid triple‐quadrupole linear ion trap mass spectrometer

Shou¹,

Magis²,

Li³

et al. 2005

J. Mass Spectrom.

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In vitro metabolic stability experiments using microsomes or other liver preparations are important components in the discovery and lead-optimization stages of compound selection in the pharmaceutical industry. Currently, liquid chromatography-tandem mass spectrometric (LC-MS/MS) support of in vitro metabolic stability studies primarily involves the monitoring of disappearance of parent compounds, using selected reaction monitoring (SRM) on triple-quadrupole instruments. If moderate to high turnover is observed, separate metabolite identification experiments are then conducted to characterize the biotransformation products. In this paper, we present a novel method to simultaneously perform metabolite screening in addition to the quantitative stability measurements, both within the same chromatographic run. This is accomplished by combining SRM and SRM-triggered, information-dependent acquisition (IDA) of MS/MS spectra on a hybrid triple-quadrupole linear ion trap (QqQLIT) mass spectrometer. Microsomal stability experiments using model compounds, bufuralol, propranolol, imipramine, midazolam, verapamil and diclofenac, were used to demonstrate the applicability of our approach. This SRM + SRM-IDA approach generated metabolic stability results similar to those obtained by conventional SRM-only approach. In addition, MS/MS spectra from potential metabolites were obtained with the enhanced product ion (EPI) scan function of LIT during the same injection. These spectra were correlated to the spectra of parent compounds to confirm the postulated structures. The time-concentration profiles of identified metabolites were also estimated from the acquired data. This approach has been successfully used to support discovery programs.

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“…Liquid chromatography/mass spectrometry (LC/MS) is a convenient way of determining trace levels of drugs in a variety of biosamples and screening for their metabolites. Data‐dependent scanning uses specified criteria to select one or more ions of interest for tandem mass spectrometry (MS/MS) and subsequent multi‐stage mass spectrometry (MS n ) analysis, which has been widely used in the identification of drug metabolites 19–24. It is capable of providing important structural information of potential metabolites on the chromatographic time scale.…”

mentioning

confidence: 99%

Profiling the metabolic difference of seven tanshinones using high‐performance liquid chromatography/multi‐stage mass spectrometry with data‐dependent acquisition

Sun¹,

Yang²,

Han³

et al. 2007

Rapid Comm Mass Spectrometry

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Tanshinones are a class of bioactive constituents in the roots of Salvia miltiorrhiza named Dan-Shen in Chinese, which possess diverse pharmacological activities. In this study, we employed a sensitive high-performance liquid chromatography/multi-stage mass spectrometry (HPLC/MS(n)) method with data-dependent acquisition and a dynamic exclusion program for the identification of phase I metabolites of seven tanshinones in rat bile after intravenous administration. These seven tanshinones are tanshinone IIA, sodium tanshinone IIA sulfonate (abbreviated as STS, a water-soluble derivate of tanshinone IIA), cryptotanshinone, 15,16-dihydrotanshinone I, tanshinone IIB, przewaquinone A and tanshinone I. Altogether 33 metabolites underwent monohydroxylation, dihydroxylation, dehydrogenation, D-ring hydrolysis or oxidation reactions in the C-4 or C-15 side chain which were characterized by analyzing the LC/MS(n) data. Different metabolic reactions for tanshinones were dependent on the degree of saturation and the substituent group in the skeleton. Dehydrogenation was the major metabolic modification for cryptotanshinone with saturated A and D rings. 15,16-Dihydrotanshinone I containing a saturated D ring was mainly metabolized through D-ring hydrolysis. For tanshinone IIA, possessing a saturated A ring, hydroxylation was the major metabolic pathway. When there was hydroxyl group substitution in the C-17 or C-18 position, such as przewaquinone A and tanshinone IIB, or sulfonic group substitution in the C-16 position, such as STS, higher metabolic stability than that of tanshinone IIA was shown and only trace metabolites were generated. Oxidation in the C-4 or C-15 side chain was a characteristic reaction for tanshinone IIA and hydroxylated tanshinone IIA. For tanshinone I, bearing unsaturated A and D rings simultaneously, no metabolites were detected.

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Simultaneous measurement of metabolic stability and metabolite identification of 7‐methoxymethylthiazolo[3,2‐a]pyrimidin‐5‐one derivatives in human liver microsomes using liquid chromatography/ion‐trap mass spectrometry

Cited by 13 publications

References 11 publications

High-performance liquid chromatography–tandem mass spectrometry in the identification and determination of phase I and phase II drug metabolites

High-performance liquid chromatography–tandem mass spectrometry in the identification and determination of phase I and phase II drug metabolites

A novel approach to perform metabolite screening during the quantitative LC–MS/MS analyses of in vitro metabolic stability samples using a hybrid triple‐quadrupole linear ion trap mass spectrometer

Profiling the metabolic difference of seven tanshinones using high‐performance liquid chromatography/multi‐stage mass spectrometry with data‐dependent acquisition

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