Abstract:
:Various carboxylic acid esters of the N-hydroxymethyl derivative of N-benzyloxycarbonylglycine benzylamide, used as a peptide-like model, were prepared and their decomposition kinetics studied in aqueous solution and in human plasma solutions. These N-acyloxymethylamide derivatives were found to undergo a facile decomposition by a pH-independent process in the pH range 4-8.5, the half-lives being 1-11hr at 37 degrees C. The cause of this limited stability was suggested to be due to the occurrence of an elimination-addition mechanism involving a reactive N-acylminium ion intermediate. In alkaline solutions (pH greater than 10) the derivatives showed a normal ester stability. The ester group in the N-acyloxymethyl derivatives was readily hydrolyzed by plasma enzymes to yield the N-hydroxymethyl amide, which subsequently decomposed to the parent amide. The results obtained suggest that N-acyloxymethylation of a peptide bond may be a useful prodrug approach to obtain derivatives with varying lipophilicities and a ready ability to undergo conversion to the parent peptide in vivo. However, the stability of the derivatives in aqueous solutions is limited.
journal_name
Pharm Resjournal_title
Pharmaceutical researchauthors
Bundgaard H,Rasmussen GJdoi
10.1023/a:1015839426229subject
Has Abstractpub_date
1991-10-01 00:00:00pages
1238-42issue
10eissn
0724-8741issn
1573-904Xjournal_volume
8pub_type
杂志文章abstract::Transdermal drug delivery of ionized drugs can be enhanced by iontophoresis. Drug in the ionic form, contained in some reservoir, can be "phoresed" through the skin with a small current across two electrodes, one above the reservoir and one at a distal skin location. Positive ions can be introduced from the positive p...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/A:1016327822325
更新日期:1986-12-01 00:00:00
abstract:PURPOSE:The growing amount of heterogeneous bioactivity data requires effective strategies to assess the promiscuity/selectivity of small-molecules and aid drug discovery. In the current study, we aim to evaluate the potential of assay profiles (APs, i.e., unique combinations of assay-related features describing how ac...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-018-2523-1
更新日期:2018-10-18 00:00:00
abstract:PURPOSE:(i) To use trehalose as a model compound to evaluate the concept of crystallinity in pharmaceuticals. (ii) To understand the structural nature of dehydrated trehalose dihydrate. MATERIALS AND METHODS:Trehalose dihydrate was dehydrated isothermally at several temperatures below 100 degrees C and the anhydrous p...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-006-9058-6
更新日期:2006-10-01 00:00:00
abstract:PURPOSE:To explore the application of scanning ion occlusion sensing (SIOS) as a novel technology for characterization of nanoparticles. METHODS:Liposomes were employed as model nanoparticles. The size distribution of the liposomes was measured by both SIOS and dynamic light scattering (DLS). Particle number concentra...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-012-0788-3
更新日期:2012-09-01 00:00:00
abstract:PURPOSE:Near-infrared reflectance spectroscopy (NIRS) was used to evaluate and quantify the effect of compression force on the NIR spectra of tablets. METHODS:Flat, white tablets with no orientation (scoring, etc.) were manufactured on a Stokes Rotary Tablet Press. NIRS was used to predict tablet hardness on the follo...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1012071904673
更新日期:1997-01-01 00:00:00
abstract::Excessive production of reactive oxygen species by alveolar macrophages (AMs) in response to inhaled toxic substances is a major cause of oxidative lung injury. Therapeutic approaches designed to protect the lungs from oxidative injury by administering native antioxidant enzymes such as catalase and superoxide dismuta...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1018976529766
更新日期:1994-08-01 00:00:00
abstract:PURPOSE:To demonstrate the applicability of thermally stimulated current (TSC) spectrometry for the detection of low levels of the amorphous phase in crystalline pharmaceutical materials. METHODS:A crystalline drug substance was melt quenched to produce an amorphous material. Blends of the crystalline and amorphous ph...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1011087012826
更新日期:2001-01-01 00:00:00
abstract:PURPOSE:In this work, the alacepril thiolesterase, which catalyzes the hydrolyzing reaction of the thiolester linkage in alacepril and the conversion from alacepril to deacetylalacepril, was purified from rat liver cytosol and characterized. METHODS:A purification procedure for the thiolesterase consisted of ammonium ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1025073720126
更新日期:2003-08-01 00:00:00
abstract:PURPOSES:To evaluate the effects of component contents in different colistin methanesulfonate (CMS) formulas on their clinical pharmacokinetics of the prodrug CMS and the formed colistin. METHODS:Two CMS formulas (CTTQ and Parkedale) were investigated in a single dose, randomized, open-label, crossover study conducted...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-021-02991-4
更新日期:2021-01-26 00:00:00
abstract:PURPOSE:A polysaccharide-flavonoid conjugate was developend and proposed for the treatment of pancreatic ductal adenocarcinoma (PDAC). METHODS:The conjugate was synthesized by free radical grafting reaction between catechin and dextran. The chemical characterization of the conjugate was obtained by UV-Vis, 1H-NMR, FT-...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-012-0790-9
更新日期:2012-09-01 00:00:00
abstract:PURPOSE:The purpose of this work was to determine whether a new modeling methodology using fuzzy logic c an predict skin permeability coefficients that are given compound descriptors that have been proven to affect percutaneous penetration. METHOD:Three fuzzy inference models were developed using subtractive clusterin...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1022273115847
更新日期:2003-02-01 00:00:00
abstract::We describe a simplified and rapid liquid chromatographic determination of antipyrine clearance (CLAP) calculated from peak height ratios of drug/internal standard. Saliva or plasma was collected 24 hr after the oral administration of 1 g of antipyrine to the subject. A 25-microliter aliquot of the sample is deprotein...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015816825920
更新日期:1991-02-01 00:00:00
abstract:PURPOSE:Safe, targeted delivery of therapeutics remains a focus of drug/gene delivery, the aim being to achieve optimal efficacy while minimising off-target delivery. Dendrimers have a vast array of potential applications and have great potential as gene and drug delivery tools. We previously reported the development o...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-014-1408-1
更新日期:2014-11-01 00:00:00
abstract:PURPOSE:Percutaneous absorption assays of molecules for pharmaceutical and cosmetology purposes are important to determine the bioavailability of new compounds, once topically applied. The current method of choice is to measure the rate of diffusion through excised human skin using a diffusion cell. This method however...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-015-1654-x
更新日期:2015-08-01 00:00:00
abstract::An alternative procedure for the simultaneous determination of trimethoprim and sulfamethoxazole in an intravenous pharmaceutical formulation is presented. Infrared spectra of 14 calibration and 6 validation samples were collected using Fourier transform-infrared/attenuated total reflectance (FT-IR/ATR). Partial least...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015957632242
更新日期:1989-07-01 00:00:00
abstract:PURPOSE:The purpose of this study was to establish a useful methodology, possibly providing information on the stoichiometry of pharmaceutical drug salts obtained from salt screening by using a multiwell plate and a Raman microscope. METHODS:Tamoxifen salt screening was conducted with monobasic and polybasic acids on ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-006-9644-7
更新日期:2006-04-01 00:00:00
abstract::High molecular weight drugs in general, and peptides in particular, are usually delivered by parenteral route because they are poorly absorbed or degraded in the gastrointestinal tract. To optimize therapy, it is desirable to search for nonparenteral routes of administration and to deliver the drug in a controlled-rel...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1018948924992
更新日期:1993-06-01 00:00:00
abstract:PURPOSE:Recombinant human serum albumin (rHSA), secreted by a Pichia pastoris expression system, was purified by a fast and efficient method, the essential feature of which is strong but reversible binding of the protein to Blue Sepharose. The structural characteristics, stability, and ligand-binding properties of the ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1013391001141
更新日期:2001-12-01 00:00:00
abstract::Animal models are used commonly in various stages of drug discovery and development to aid in the prospective assessment of drug-drug interaction (DDI) potential and the understanding of the underlying mechanism for DDI of a drug candidate. In vivo assessments in an appropriate animal model can be very valuable, when ...
journal_title:Pharmaceutical research
pub_type: 杂志文章,评审
doi:10.1007/s11095-010-0157-z
更新日期:2010-09-01 00:00:00
abstract:PURPOSE:The aim of this study was to identify new surfactants with low skin irritant properties for use in pharmaceutical and cosmetic formulations, employing cell culture as an alternative method to in vivo testing. In addition, we sought to establish whether potential cytotoxic properties were related to the size of ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/b:pham.0000041459.63362.6f
更新日期:2004-09-01 00:00:00
abstract::The possible mechanism of hepatic uptake of colchicine (CLC), a microtubule system disrupting agent, was examined using isolated rat hepatocytes. The existence of a carrier-mediated active transport system for CLC was demonstrated. This transport system is saturable, is affected by metabolic inhibitors (dinitrophenol,...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015917601349
更新日期:1989-03-01 00:00:00
abstract:PURPOSE:The purpose of this study was to investigate the delivery of itraconazole (ITZ) particles to a murine lung model by nebulization. METHODS:Three ITZ formulations were prepared and characterized in the dry state using contact angle, dissolution, X-ray powder diffraction, scanning electron microscopy, and Brunaue...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-006-9904-6
更新日期:2006-05-01 00:00:00
abstract:PURPOSE:The cause of antibody positive pure red cell aplasia associated with the subcutaneous administration of EPREX to patients with chronic kidney failure has been determined to be due to the leaching of weakly adjuvant compounds from the uncoated rubber stoppers that were formerly used in prefilled syringes. Other ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-005-5356-7
更新日期:2005-07-01 00:00:00
abstract:PURPOSE:Grapefruit juice (GJ) is known to increase the oral bioavailability of many CYP3A-substrates by inhibiting intestinal phase-I metabolism. However, the magnitude of AUC increase is often insignificant and highly variable. Since we earlier suggested that CYP3A and P-glycoprotein (P-gp) form a concerted barrier to...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1011902625609
更新日期:1999-04-01 00:00:00
abstract:PURPOSE:To investigate whether conjunctival epithelial cells express transport processes for opioid peptides. METHODS:We monitored the uptake of [(3)H]deltorphin II and [(3)H]DADLE, two hydrolysis-resistant synthetic opioid peptides, in the rabbit conjunctival epithelial cell line CJVE and elucidated the characteristi...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-008-9709-x
更新日期:2009-05-01 00:00:00
abstract:PURPOSE:To investigate the influence of primary crystallization conditions on the mechanical properties and secondary processing behaviour of fluticasone propionate (FP) for carrier based dry powder inhaler (DPI) formulations. METHODS:Young's modulus of FP crystals produced using different anti-solvents was determined...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-011-0640-1
更新日期:2012-04-01 00:00:00
abstract::Inhibition of efflux pumps is an emerging approach in cancer therapy and drug delivery. Since it has been discovered that polymeric pharmaceutical excipients such as Tweens or Pluronics can inhibit efflux pumps, various other polymers have been investigated regarding their potential efflux pump inhibitory activity. Am...
journal_title:Pharmaceutical research
pub_type: 杂志文章,评审
doi:10.1007/s11095-007-9347-8
更新日期:2008-03-01 00:00:00
abstract::The internalization of a neuromodulatory adrenocorticotropic hormone (ACTH) analogue, [125I]ebiratide (H-Met(O2)-Glu[125I]His-Phe-D-Lys-Phe-NH(CH2)2NH2), was examined in cultured monolayers of bovine brain capillary endothelial cells (BCEC). HPLC analysis of the incubation solution showed that [125I]ebiratide was not ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015848531603
更新日期:1992-04-01 00:00:00
abstract::A fluorescence measurement system and methods of data analysis were developed to measure rapid kinetics of transdermal transport in vitro. Three variations on the technique were demonstrated, where the receptor compartment concentration was determined by: 1) fluorescence measurements of aliquots removed at discrete ti...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1016254013374
更新日期:1995-04-01 00:00:00
abstract:PURPOSE:To examine whether the glass transition temperature (Tg) of freeze-dried formulations containing polymer excipients can be accurately predicted by molecular dynamics simulation using software currently available on the market. Molecular dynamics simulations were carried out for isomaltodecaose, a fragment of de...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1023831102203
更新日期:2003-06-01 00:00:00