Dataset Information

Differentiating Isomeric Deprotonated Glucuronide Drug Metabolites via Ion/Molecule Reactions in Tandem Mass Spectrometry.

ABSTRACT: Isomeric O- and N-glucuronides are common drug metabolites produced in phase II of drug metabolism. Distinguishing these isomers by using common analytical techniques has proven challenging. A tandem mass spectrometric method based on gas-phase ion/molecule reactions of deprotonated glucuronide drug metabolites with trichlorosilane (HSiCl₃) in a linear quadrupole ion trap mass spectrometer is reported here to readily enable differentiation of the O- and N-isomers. The major product ion observed upon reactions of HSiCl₃ with deprotonated N-glucuronides is a diagnostic HSiCl₃ adduct that has lost two HCl molecules ([M - H + HSiCl₃ - 2HCl]-). This product ion was not observed for deprotonated O-glucuronides. Reaction mechanisms were explored with quantum chemical calculations at the M06-2X/6-311++G(d,p) level of theory.

SUBMITTER: Kong JY

PROVIDER: S-EPMC6686676 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Differentiating Isomeric Deprotonated Glucuronide Drug Metabolites via Ion/Molecule Reactions in Tandem Mass Spectrometry.

Kong John Y JY Yu Zaikuan Z Easton Mckay W MW Niyonsaba Edouard E Ma Xin X Yerabolu Ravikiran R Sheng Huaming H Jarrell Tiffany M TM Zhang Zhoupeng Z Ghosh Arun K AK Kenttämaa Hilkka I HI

Analytical chemistry 20180723 15

Isomeric O- and N-glucuronides are common drug metabolites produced in phase II of drug metabolism. Distinguishing these isomers by using common analytical techniques has proven challenging. A tandem mass spectrometric method based on gas-phase ion/molecule reactions of deprotonated glucuronide drug metabolites with trichlorosilane (HSiCl<sub>3</sub>) in a linear quadrupole ion trap mass spectrometer is reported here to readily enable differentiation of the O- and N-isomers. The major product io ...[more]

PMID: 29984992

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Dataset Information

Differentiating Isomeric Deprotonated Glucuronide Drug Metabolites via Ion/Molecule Reactions in Tandem Mass Spectrometry.

Publications

Differentiating Isomeric Deprotonated Glucuronide Drug Metabolites via Ion/Molecule Reactions in Tandem Mass Spectrometry.

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