Analysis of estrogen glucuronides. I—characterization of estrogen glucuronides by gas chromatography mass spectrometry

Abstract

The mass spectral characterization of nine kinds of estrogen glucuronides was investigated. The glucuronides were analysed after conversion to n-propyl ester-O-TMS ether derivatives by gas chromatography mass spectrometry. The fragmentation of these derivatives is discussed using deuterium labels and TMS-d9 imidazole. A clear-cut difference was found between aliphatic and aromatic glucuronic acid conjugates. In particular the [M - 362]+- fragment ion was characteristic in the mass spectra of estrogen 3-glucuronides. On the other hand, four isomers of estriol and 16-epiestriol glucuronides containing an aliphatic acetal linkage were also characterized by the fragment ions of m/e value 204, 345, 415, and 431 and their relative intensities. Thus, all nine estrogen glucuronides were discriminated mass spectrometrically.

Mass spectral characterization of the glucuronic acid conjugate of a metabolite of suloctidil in the rhesus monkey

“…Important ions in glucuronide identification like those at mle 635,545,464,465,313,305 and 204 appeared to be more intense in the mass spectrum of the persilylated derivative compared to the corresponding ions of the methylated/silylated derivative. The comparable intensities of the ions mle 464 and 465 of the persilylated derivative and the ions mle 406 and 407 of the other derivative are consistent with the presence of an aliphatic OR-group through which the aglycone is conjugated with the glucuronic acid (25). The differences we observed between the spectra of both derivatives are mostly ill agreement with these observed by Bakke et al (9) for the aliphatic bound glucuronide of a metabolite of crufomate.…”

Mass Spectrometric Fragmentation of Trimethylsilyl and Related Alkylsilyl Derivatives

“…Also present are the common carbohydrate‐derived ions at m/z 275 ( fg ), 217 ( z ) and 204 ( eo ). Glucuronides in which the glucuronic acid is conjugated via an aromatic hydroxyl group undergo a rearrangement involving a TMS migration to the aromatic hydroxyl group (Billets et al, ; Miyazaki et al, ; Mrochek & Rainey, ; Spiegelhalder et al, ) and loss of 334 mass units (methyl esters). Aliphatically‐linked glucuronides, on the other hand, eliminate the intact sugar residue to leave a carbonium ion.…”

More acidic metabolites of Δ1-tetrahydrocannabinol isolated from rabbit urine

“…peak 6 was methyl 2"-hydroxy-Al-THC-7-oate (VI, @ 7 y 0 , , R~ = 0.30, Rt = 2. Phenolic linkage was confirmed by the fragments at m/e 406 (Miyazaki et al 1976) and at mle 386 (Billets et a1 1973). The failure to detect VII with a phenol sensitive spray and the p.m.r.…”