Abstract:
PURPOSE:To show, using a model study, how electronic structure theory can be applied in combination with LC/UV/MS/MS for the prediction and identification of oxidative degradants. METHODS:The benzyloxazole 1, was used to represent an active pharmaceutical ingredient for oxidative forced degradation studies. Bond dissociation energies (BDEs) calculated at the B3LYP/6-311+G(d,p)//B3LYP/6-31G(d) level with isodesmic corrections were used to predict sites of autoxidation. In addition, frontier molecular orbital (FMO) theory at the Hartree-Fock level was used to predict sites of peroxide oxidation and electron transfer. Compound 1 was then subjected to autoxidation and H2O2 forced degradation as well as formal stability conditions. Samples were analyzed by LC/UV/MS/MS and degradation products proposed. RESULTS:The computational BDEs and FMO analysis of 1 was consistent with the LC/UV/MS/MS data and allowed for structural proposals, which were confirmed by LC/MS/NMR. The autoxidation conditions yielded a number of degradants not observed under peroxide degradation while formal stability conditions gave both peroxide and autoxidation degradants. CONCLUSIONS:Electronic structure methods were successfully applied in combination with LC/UV/MS/MS to predict degradation pathways and assist in spectral identification. The degradation and excipient stability studies highlight the importance of including both peroxide and autoxidation conditions in forced degradation studies.
journal_name
Pharm Resjournal_title
Pharmaceutical researchauthors
Reid DL,Calvitt CJ,Zell MT,Miller KG,Kingsmill CAdoi
10.1023/b:pham.0000041469.96466.12subject
Has Abstractpub_date
2004-09-01 00:00:00pages
1708-17issue
9eissn
0724-8741issn
1573-904Xjournal_volume
21pub_type
杂志文章abstract:PURPOSE:Following extracellular drug clearance, we analyzed the rate of doxorubicin efflux from the nucleus of three human leukemic cells (K562, Molt4 and CCRF-CEM) and related it to their differential sensitivity to this drug, after a short drug pulse. RESULTS:For many pulse-chase regimes, K562 cell viability was lea...
journal_title:Pharmaceutical research
pub_type: 杂志文章
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更新日期:2007-11-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
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journal_title:Pharmaceutical research
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journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-018-2392-7
更新日期:2018-03-29 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
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abstract:PURPOSE:The purpose was to develop a population pharmacokinetic model for montelukast after intravenous administration. Clinical trial simulations were conducted using the model developed to identify the lowest intravenous dose in 6- to 14-year-old children that would give montelukast systemic exposures that were compa...
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pub_type: 杂志文章,随机对照试验
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abstract:PURPOSE:Evista (raloxifene HCl) is a nonsteroidal selective estrogen receptor modulator that displays estrogen agonist effects on bone and lipid metabolism but estrogen antagonist effects on the breast and endometrium. The potential for drug-drug interaction between raloxifene and warfarin was assessed in 15 healthy po...
journal_title:Pharmaceutical research
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doi:10.1007/s11095-015-1667-5
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pub_type: 杂志文章
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abstract::A novel application of attenuated total reflectance IR spectroscopy (ATR-IR) was used to monitor the outer several microns of the stratum corneum (SC) and, thereby, demonstrate enhanced percutaneous absorption in vivo in man. 4-Cyanophenol (CP) as a model permeant yielded a unique IR signal, distinct from those of the...
journal_title:Pharmaceutical research
pub_type: 杂志文章
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更新日期:1990-08-01 00:00:00
abstract::A new high-performance liquid chromatographic (HPLC) assay suitable for pharmacokinetic studies of enantiomers of fenoprofen (FEN) was developed. Following the addition of internal standard (IS; racemic ketoprofen), the plasma or urine constituents are extracted into a mixture of isooctane:isopropanol (95:5), back ext...
journal_title:Pharmaceutical research
pub_type: 杂志文章
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更新日期:1988-01-01 00:00:00
abstract:PURPOSE:The aim of the present study was to design a new mucosal drug delivery system composed of liposomes dispersed within a bioadhesive hydrogel containing methyl-beta-cyclodextrin (Me(beta)CD) for controlled drug release. METHODS:A hydrophilic model molecule, inulin, was encapsulated within positively charged and ...
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doi:10.1007/s11095-005-4591-2
更新日期:2005-06-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1016225707807
更新日期:1995-09-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-008-9564-9
更新日期:2008-07-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015803922401
更新日期:1992-09-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-013-1094-4
更新日期:2013-10-01 00:00:00
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journal_title:Pharmaceutical research
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doi:10.1023/a:1015917601349
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pub_type: 杂志文章
doi:10.1007/s11095-010-0221-8
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pub_type: 杂志文章
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更新日期:1992-10-01 00:00:00
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pub_type: 杂志文章
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更新日期:2015-06-01 00:00:00
abstract:PURPOSE:To compare the permeation characteristics of amide bond-containing HIV-1 protease inhibitors and their pyrrolinone-containing counterparts across Caco-2 cell monolayers, a model of the intestinal mucosa. METHODS:Transepithelial transport and cellular uptake of three pairs of amide bond-containing and pyrrolino...
journal_title:Pharmaceutical research
pub_type: 杂志文章
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更新日期:1998-05-01 00:00:00
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pub_type: 杂志文章
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更新日期:2012-01-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-010-0317-1
更新日期:2011-03-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1018967401000
更新日期:1994-12-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章,评审
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更新日期:1989-09-01 00:00:00
abstract:PURPOSE:Since the molecular mechanism of the cell cycle was established, various theoretical models of this process have been developed. A recent study revealed significant variability in cell cycle duration between mother and daughter cells, but this observation has not been incorporated into the theoretical models. ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
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更新日期:2019-02-22 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
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更新日期:2016-05-01 00:00:00
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journal_title:Pharmaceutical research
pub_type: 杂志文章
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更新日期:1999-02-01 00:00:00