Abstract:
:The physicochemical properties and crystal structures of the crystalline salts formed by the interaction of an achiral anion, salicylate, with homochiral and racemic ephedrinium and pseudoephedrinium cations were determined. The interaction of ephedrinium or pseudoephedrinium with salicylate in aqueous solution yielded crystalline salts with the notable exception of homochiral ephedrinium. Evaporation of the solvent from solutions of homochiral ephedrine and salicyclic acid in various organic solvents, as well as grinding together solid homochiral ephedrine and solid salicylic acid, yielded viscous semisolids suggesting that homochiral ephedrinium salicylate has a low melting point and/or a high aqueous solubility. Mixing of the two viscous solids, obtained by grinding each of the opposite enantiomers of ephedrine with equimolar salicylic acid, resulted in the formation of racemic ephedrine and subsequently, upon heating, in the formation of racemic ephedrinium salicylate. While racemic ephedrinium salicylate exists as a crystalline compound (P2(1)/n space group) with an equal number of opposite enantiomers in the unit cell, its diastereomer, racemic pseudoephedrinium salicylate, exists as a conglomerate, i.e. a physical mixture, of the homochiral crystals of the opposite enantiomers (each P2(1) space group). The inability of homochiral ephedrinium to exist as a crystalline salicylate salt at 20-25 degrees C is attributed to its high energy conformation and/or to the poor packing of homochiral ephedrinium salicylate molecules in the crystal lattice.
journal_name
Pharm Resjournal_title
Pharmaceutical researchauthors
Duddu SP,Grant DJdoi
10.1023/a:1018945401484subject
Has Abstractpub_date
1994-11-01 00:00:00pages
1549-56issue
11eissn
0724-8741issn
1573-904Xjournal_volume
11pub_type
杂志文章abstract:PURPOSE:The purpose of this study was to evaluate the feasibility of delivering vapreotide, a somatostatin analogue, by transdermal iontophoresis. METHODS:In vitro experiments were conducted using dermatomed porcine ear skin and heat-separated epidermis. In addition to quantifying vapreotide transport into and across ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-005-5276-6
更新日期:2005-08-01 00:00:00
abstract:PURPOSE:To study the miscibility of proteins and polymer excipients in frozen solutions and freeze-dried solids as protein formulation models. METHODS:Thermal profiles of frozen solutions and freeze-dried solids containing various proteins (lysozyme, ovalbumin, BSA), nonionic polymers (Ficoll, polyvinylpyrrolidone [PV...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1026412107574
更新日期:2000-10-01 00:00:00
abstract:PURPOSE:There is evidence that cholesterol affects the ATPase and transport functions of P-glycoprotein (P-gp). To study the influence of cholesterol on P-gp in a well defined lipid environment, we reconstituted P-gp in egg phosphatidylcholine (PhC) and PhC/cholesterol proteoliposomes with negligible residual amounts o...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-007-9326-0
更新日期:2007-11-01 00:00:00
abstract:PURPOSE:The purpose of this work was to determine the jejunal permeability of cyclosporin A (CsA) in humans and whether formulation variables modulate the effects of P-glycoprotein (P-gp) on the permeability of CsA in Caco-2 cells. METHODS:A solution containing CsA, phenylalanine, propranolol, polyethyleneglycol (PEG)...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1023481418576
更新日期:2003-05-01 00:00:00
abstract::The pharmacokinetic parameters of leuprolide acetate, a potent analogue of LH-RH, were determined in rats and dogs after i.v. and s.c. dosing with leuprolide solution. The effective human dose of once-a-month injectable microspheres of leuprolide was estimated to be about 3.2 to 8.1 mg analogue/month using these param...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015818504906
更新日期:1991-06-01 00:00:00
abstract:PURPOSE:To quantitatively compare in vitro dissolution data in biorelevant and compendial media, to investigate whether in vitro differences are reflected in the simulated plasma profile and to specify under which circumstances prediction of the plasma profile of orally administered lipophilic drugs can be achieved. M...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1011071401306
更新日期:2001-03-01 00:00:00
abstract:PURPOSE:Heparin immobilized porous poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres were prepared for sustained release of basic fibroblast growth factor (bFGF) to induce angiogenesis. MATERIALS AND METHODS:Porous PLGA microspheres having primary amine groups on the surface were prepared using an oil-in-water (O/...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-006-9039-9
更新日期:2006-08-01 00:00:00
abstract:PURPOSE:To evaluate the potential of several bis-ester prodrugs of the antiviral agent 9-(2-phosphonylmethoxyethyl)adenine (PMEA, adefovir) to enhance the oral absorption of PMEA. METHODS:Caco-2 monolayers were used to estimate intestinal transport and metabolism of the bis(pivaloyloxymethyl)-ester [bis(POM)-] and a s...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1011914618109
更新日期:1998-02-01 00:00:00
abstract::A method for determination of absorption rate and bioavailability was developed to reduce the influence of intraindividual variability and applied to the absolute intraperitoneal availability of lithium in the rat. In this method the test and the reference doses are given with a few hours' interval, and the resulting ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015939917646
更新日期:1989-09-01 00:00:00
abstract::Significant efforts are made to characterize molecular liabilities and degradation of the drug substance (DS) and drug product (DP) during various product life-cycle stages. The in vivo fate of a therapeutic protein is usually only considered in terms of pharmacokinetics (PKs) and pharmacodynamics (PDs). However, the ...
journal_title:Pharmaceutical research
pub_type: 杂志文章,评审
doi:10.1007/s11095-019-2689-1
更新日期:2020-01-03 00:00:00
abstract::The delivery of therapeutic nucleic acids to neurons has the potential to treat neurological disease and spinal cord injury. While select viral vectors have shown promise as gene carriers to neurons, their potential as therapeutic agents is limited by their toxicity and immunogenicity, their broad tropism, and the cos...
journal_title:Pharmaceutical research
pub_type: 杂志文章,评审
doi:10.1007/s11095-007-9439-5
更新日期:2008-05-01 00:00:00
abstract:PURPOSE:Novel itraconazole (ITZ)-based dry powders for inhalation (DPI) were optimized for aerodynamic and dissolution properties and contained excipients that are acceptable for inhalation. METHODS:The DPI were produced by spray drying solutions. The drug content, crystallinity state, and morphological evaluation of ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-012-0779-4
更新日期:2012-10-01 00:00:00
abstract::Lidocaine was administered to healthy volunteers at different sites in the rectum. Unchanged drug and monoethylglycinexylidide (MEGX) concentrations were measured in plasma with a newly developed gas chromatographic method. Lidocaine was given rectally by means of an osmotic system (Osmet(®)) which delivered 25 mg/h a...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/A:1016380104424
更新日期:1984-05-01 00:00:00
abstract::One thousand milligrams of aspirin, as its lysine salt was administered intravenously, orally, and intramuscularly to nine male and nine female young healthy adult volunteers. After intravenous injection mean (+/- SD) values of clearance, steady-state volume of distribution, and terminal half-life were 12.2 +/- 2.2 ml...
journal_title:Pharmaceutical research
pub_type: 临床试验,杂志文章
doi:10.1023/a:1015978104017
更新日期:1989-08-01 00:00:00
abstract:PURPOSE:The in-situ particle size of delavirdine mesylate in dry mix and tablets was determined. METHODS:Optical microscopy and fluorescence microscopy combined with image analysis were used for qualitative and quantitative measurements. RESULTS:Using optical microscopy, it was demonstrated qualitatively that fragmen...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1018875130152
更新日期:1999-04-01 00:00:00
abstract::The pharmacokinetics of cefixime, a new orally active cephalosporin, was studied after an intravenous dose of 50 mg/kg to four beagle dogs. Cefixime was shown to exhibit concentration dependent serum protein binding and saturable tubular reabsorption. The drug was excreted mainly in the urine, the net result of glomer...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/A:1016309923717
更新日期:1986-06-01 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:To examine the theoretical/practical utility of the liver-to-blood partition coefficient (Kpuu) for predicting drug-drug interactions (DDIs), and compare the Kpuu-approach to the extended clearance concept AUCR-approach. METHODS:The Kpuu relationship was derived from first principles. Theoretical simulations i...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-020-02797-w
更新日期:2020-03-25 00:00:00
abstract:PURPOSE:The development of a physiologically based absorption model for orally administered drugs in rats is described. METHODS:Unlike other models that use a multicompartmental approach, the GI tract is modeled as a continuous tube with spatially varying properties. The mass transport through the intestinal lumen is ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/b:pham.0000003373.72652.c0
更新日期:2003-11-01 00:00:00
abstract::This review describes the design and current development of leukotriene biosynthesis inhibitors as potential antiinflammatory agents. Knowledge of the enzymatic mechanism of 5-lipoxygenase led to specific inhibitors of this enzyme which catalyzes a key step in the leukotriene pathway. Competitive inhibitors include ir...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/A:1016381215385
更新日期:1985-11-01 00:00:00
abstract::Molecular modeling has been used to study the complexation between alpha, beta, or gamma-cyclodextrin (CD) and a group of amine compounds having the diphenylmethyl functionality. The computer program SYBYL 5.3 and the Tripos force field (version 5.2) were used for all the calculations. Three-dimensional structures of ...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015816215751
更新日期:1991-10-01 00:00:00
abstract:PURPOSE:To develop novel bioactive-chylomicrons to solve oral delivery obstacles of Berberine chloride and target the lymphatic system. METHODS:Berberine-loaded bioactive-chylomicrons were prepared and underwent full in vitro characterization. Intestinal permeability was appraised via both non-everted gut sac model an...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-017-2307-z
更新日期:2018-01-05 00:00:00
abstract:PURPOSE:The gadopentetic acid (Gd-DTPA)-loaded chitosan nanoparticles (Gd-nanoCPs) were prepared for gadolinium neutron-capture therapy (Gd-NCT) and characterized and evaluated as a device for intratumoral (i.t.) injection. METHODS:Gd-nanoCPs were prepared by a novel emulsion-droplet coalescence technique. The effects...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1018995124527
更新日期:1999-12-01 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::A simple viscometric method was used to quantify mucin-polymer bioadhesive bond strength. Viscosities of 15% (w/v) porcine gastric mucin dispersions in 0.1 N HCl (pH 1) or 0.1 N acetate buffer (pH 5.5) were measured with a Brookfield viscometer in the absence (eta m) or presence (eta t) of selected neutral, anionic, a...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1015812615635
更新日期:1990-05-01 00:00:00
abstract:PURPOSE:A thermodynamic analysis of the binding to rat cortex adenosine A1 receptor of N6-substituted (full agonists) and N6-substituted-deoxyribose (partial agonists) adenosine derivatives was performed. The intrinsic activity of the compounds was evaluated by measurements of the inhibition of forskolin stimulated 3',...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1018987816891
更新日期:1999-07-01 00:00:00
abstract:PURPOSE:Novel multidrug resistance (mdr) modulators have been proved as inhibitors of P-glycoprotein (P-gp). We first investigated the in vitro effects of selected compounds in human cancer cells on multidrug resistance reversal effects compared to drug standards and on P-gp induction to characterize the potential of t...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-008-9736-7
更新日期:2009-01-01 00:00:00
abstract:PURPOSE:The possibility of preparing nanoparticles in the supercooled thermotropic liquid crystalline state from cholesterol esters with saturated acyl chains as well as the incorporation of model drugs into the dispersions was investigated using cholesteryl myristate (CM) as a model cholesterol ester. METHODS:Nanopar...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/b:pham.0000045237.46019.6e
更新日期:2004-10-01 00:00:00
abstract:PURPOSE:To demonstrate that polyanhydride copolymer chemistry affects the uptake and intracellular compartmentalization of nanospheres by THP-1 human monocytic cells. METHODS:Polyanhydride nanospheres were prepared by an anti-solvent nanoprecipitation technique. Morphology and particle diameter were confirmed via scan...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1007/s11095-008-9760-7
更新日期:2009-03-01 00:00:00
abstract:PURPOSE:To study epidermal and polyethylene membrane penetration and retention of the sunscreen benzophenone-3 (BP) from a range of single solvent vehicles and evaluate solvent effects on permeability parameters. METHODS:The solubility of BP was measured in a number of solvents. Penetration of BP across human epidermi...
journal_title:Pharmaceutical research
pub_type: 杂志文章
doi:10.1023/a:1011958006973
更新日期:1998-12-01 00:00:00