Glyburide metabolites

Tiller, P. R. Land, A. P Jardine, I. Murphy, D. M. Sozio, R. Ayrton, A. Schaefer, W. H. 1998. Application of liquid chromatography-mass spectrometry analyses to the characterization of novel glyburide metabolites formed in vitro. /. Chromatogr. A, 794,15-25. 

P.R. Tiller, A.P. Land, I. Jardine, D.M. Murphy, R. Sozio, A. Ayrton, W.H. Schaefer, Application of LC-MS" analyses to characterize novel glyburide metabolites formed in vitro, J. Chromatogr. A, 794 (1998) 15. 

Tiller, PR. Land, A.P Jardine, L Murphy, D.M. Sozio, R. Ayrton, A. Schaefer, W.H. Application of Liquid Chromatography-mass Spectrometry Analyses to the Characterization of Novel Glyburide Metabolites Formed In Vitro, J. Chromatogr. A794, 15-25 (1998). 

A slightly different use of accurate mass measurement in drug metabolism studies has been reported [31]. In this investigation, the accurate masses of the ions derived from Glyburide (Figure 5.48) and some of its metabolites were used to calculate the difference in mass, and thus the elemental composition, between certain of the ions observed in the spectra of the various compounds. 

Table 5.14 Summary of the accurate mass differences (in Da) between the molecnlar ion of Glyburide and the molecular ions of five of its metabolites." Reprinted with permission from Zhang, H., Henion, J., Yang, Y. and Spooner, N., Anal. Chem., 72, 3342-3348 (2000). Copyright (2000) American Chemical Society...

Glyburide (DiaBeta, Micronase, Glynase), also known as glibenclamide, is approximately 150 times as potent as tolbutamide on a molar basis and twice as potent as glipizide (discussed later). Glyburide is completely metabolized in the liver to two weakly active metabolites before excretion in the urine. Its average duration of action is 24 hours. 

Glipizide (Glucotwl) is similar to glyburide, but it is metabolized by the liver to two inactive metabolites these metabolites and glipizide are renally excreted. 

Metabolism/ elimination Acetohexamide, chlorpropamide, tolazamide, glyburide glimepiride weakly active metabolites. Glipizide, tolbutamide inactive metabolites. Inactive metabolites Predominantly inactive metabolites Excreted unchanged in urine Extensively metabolized in liver to metabolites Acarbose inactive metabolites. Miglitol excreted unchanged in urine. 

Six known and two new metabolites of glyburide, a sulfonylurea dmg applied in the treatment of insulin-independent Diabetes mellitus, were identified using DDA in LC-MS" on an ion-trap instmment [39]. DDA was also applied as an alternative to precursor-ion analysis in the screening and identification of moclobemide and remikiren metabolites [32]. More recently, ion-trap MS-MS in DDA mode was applied to perform the simultaneous metabolite identification and assessment of metabolic stability [40-41]... 

Glyburide (active metabolite, -i dose in renal dysfunction)... 

Glipizide and glyburide are extensively metabolized (Fig. 32.5) to less active or inactive metabolites. Glipizide metabolites are excreted primarily in the urine, whereas glyburide s metabolites are excreted equally in the urine and bile. 

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