Anti-rheumatic activity of pseudoephedrine (a substituted phenethylamine) in complete Freund's adjuvant-induced arthritic rats by down regulating IL-1ß, IL-6 and TNF-α as well as upregulating IL-4 and IL-10.

Pseudoephedrine (substituted phenethylamine) is well known as psychotic and bronchodilator. Numerous studies on phenethylamine derivatives indicated that these agents have the potential to abolish inflammatory responses in the non-biological and biological systems. These facts provided the basis to conduct a study on pseudoephedrine to explore its therapeutics in Complete Freund's Adjuvant (CFA)-induced arthritis. Furthermore, existing treatment approaches for RA associated with limited effect on chronic immunological models. Real-time polymerase chain reaction (q-PCR) was performed to execute the expression of pro and anti-inflammatory cytokines in treated and non-treated arthritic rats. These findings were further co investigate by histological observations. The paw volume, paw diameter, weight variations and arthritic score were determined at specific days throughout the experiment of 28 days. Pseudoephedrine at all doses significantly (p < 0.001) suppressed the expression of PGE2, TNF-α, IL-1ß and IL-6. Moreover, pseudoephedrine (20 and 40 mg/kg) caused significant augmentation of IL-4 and IL-10. Similarly, the drug expressed a significant anti-arthritic effect by reducing the paw volume, paw diameter and arthritic score. Similarly, it also reverts the reduction in body weight of arthritic rats at all above-mentioned doses. These findings supported the anti-arthritic potential of pseudoephedrine and recommended it for clinical trials.

Biodegradation of Ephedrine Isomers by Arthrobacter sp. Strain TS-15: Discovery of Novel Ephedrine and Pseudoephedrine Dehydrogenases.

The Gram-positive soil bacterium Arthrobacter sp. strain TS-15 (DSM 32400), which is capable of metabolizing ephedrine as a sole source of carbon and energy, was isolated. According to 16S rRNA gene sequences and comparative genomic analysis, Arthrobacter sp. TS-15 is closely related to Arthrobacter aurescens Distinct from all known physiological paths, ephedrine metabolism by Arthrobacter sp. TS-15 is initiated by the selective oxidation of the hydroxyl function at the α-C atom, yielding methcathinone as the primary degradation product. Rational genome mining revealed a gene cluster potentially encoding the novel pathway. Two genes from the cluster, which encoded putative short-chain dehydrogenases, were cloned and expressed in Escherichia coli The obtained enzymes were strictly NAD+ dependent and catalyzed the oxidation of ephedrine to methcathinone. Pseudoephedrine dehydrogenase (PseDH) selectively converted (S,S)-(+)-pseudoephedrine and (S,R)-(+)-ephedrine to (S)- and (R)-methcathinone, respectively. Ephedrine dehydrogenase (EDH) exhibited strict selectivity for the oxidation of the diastereomers (R,S)-(-)-ephedrine and (R,R)-(-)-pseudoephedrine.IMPORTANCEArthrobacter sp. TS-15 is a newly isolated bacterium with the unique ability to degrade ephedrine isomers. The initiating steps of the novel metabolic pathway are described. Arthrobacter sp. TS-15 and its isolated ephedrine-oxidizing enzymes have potential for use in decontamination and synthetic applications.

Disodium Salts of Pseudoephedrine-Derived Myers Enolates: Stereoselectivity and Mechanism of Alkylation.

Pseudoephedrine-derived dianionic Myers enolates were generated using sodium diisopropylamide (NaDA) in THF solution. The reactivities and selectivities of the disodium salts largely mirror those of the dilithium salts but without the requisite large excesses of inorganic salts (LiCl) or mandated dilute solutions. The disodium salts require careful control of temperature to preclude deleterious aggregate aging effects traced to changes in the aggregate structure and intervening O-alkylations. Structural studies and density functional theory (DFT) computations show a dominant highly symmetric polyhedron quite different from the lithium analogue. No enolate-NaDA mixed aggregates are observed with excess NaDA. Rate studies show an alkylation mechanism involving an intervening tetramer-monomer pre-equilibrium followed by rate-limiting alkylation of tetrasolvated monomers. DFT computations were conducted to explore the possible influences on stereochemistry. A crystal deriving from samples aged at ambient temperature contains six dianionic subunits and two monoanionic (alkoxide-only) subunits. A new preparation of concentrated solutions of NaDA in THF solution is described.

Self-assembly of chiral (1R,2S)-ephedrine and (1S,2S)-pseudoephedrine into low-dimensional aluminophosphate materials driven by their amphiphilic nature.

In an attempt to promote the crystallization of chiral inorganic frameworks, we explore the ability of chiral (1R,2S)-ephedrine and its diastereoisomer (1S,2S)-pseudoephedrine to act as organic building blocks for the crystallization of hybrid organo-inorganic aluminophosphate frameworks in the presence of fluoride. These molecules were selected because of their particular molecular asymmetric structure, which enables a rich supramolecular chemistry and a potential chiral recognition phenomenon during crystallization. Up to four new low-dimensional materials have been produced, wherein the organic molecules form an organic bilayer in-between the inorganic networks. We analyze by molecular simulations the trend of these chiral molecules to form these types of framework, which is directly related to their amphiphilic nature that triggers a strong self-assembly through hydrophobic interactions between aromatic rings and hydrophilic interactions with the fluoro-aluminophosphate inorganic units. Such a self-assembly process is strongly dependent on the concentration of the organic molecules.

Determination of the pseudoephedrine content in pharmaceutical formulations and in biological fluids using a microbore HPLC system interfaced to a microfluidic chemiluminescence detector.

A novel automated precolumn derivatization followed by separation using liquid chromatography for the determination of pseudoephedrine (PSE) by a microfluidic chemiluminescence detector has been developed. An on-line derivatization procedure was utilized by converting PSE into a highly light emitting species in a Ru(bipy)3(2+)-peroxydisulphate chemiluminescence (CL) system by derivatizing it with a 1.0 M formaldehyde solution. The derivatized analyte was directly injected into a microbore high-performance liquid chromatography (HPLC) system coupled to an on-chip chemiluminescence detector. The newly developed highly selective, sensitive and fast HPLC-CL method was validated and successfully applied for the analysis of PSE in pharmaceutical formulations and a human urine sample. The selectivity of the method is not only due to the HPLC separation but is also due to the highly selective detection principle of the Ru(bipy)3(2+)-peroxydisulphate CL system used. There was no interference observed from the common preservatives and excipients used in pharmaceutical preparations, which did not show any significant CL signal. The retention time of PSE was less than 3 min, and the detection limits and quantification limits were found to be 5.7 and 26.0 µg L(-1), respectively.

Pseudoephedrine-Directed Asymmetric α-Arylation of α-Amino Acid Derivatives.

Available α-amino acids undergo arylation at their α position in an enantioselective manner on treatment with base of N'-aryl urea derivatives ligated to pseudoephedrine as a chiral auxiliary. In situ silylation and enolization induces diastereoselective migration of the N'-aryl group to the α position of the amino acid, followed by ring closure to a hydantoin with concomitant explulsion of the recyclable auxiliary. The hydrolysis of the hydantoin products provides derivatives of quaternary amino acids. The arylation avoids the use of heavy-metal additives, and is successful with a range of amino acids and with aryl rings of varying electronic character.

Model compounds for evaluating the reactivity of amphetamine-type stimulants.

The use of controlled precursors for reaction optimisation is not always practical. One approach to limiting the use of controlled substances is to instead use 'model compounds'. Herein, two model compounds resembling norephedrine and ephedrine were selected based on their (i) structural similarity (i.e., presence of key functional groups) and (ii) availability from multiple suppliers without restriction. Model compounds 2-amino-1-phenylethanol and 2-(methylamino)-1-phenylethanol (halostachine), were compared to norephedrine and pseudoephedrine by firstly subjecting them to transformations known in the synthesis of amphetamines, and secondly, comparing the compounds using colourimetric spot tests, FTIR and NMR.

Can the heptapeptide ASSIVSF of the ß2-adrenoceptor recognize ephedrine and pseudoephedrine epimers in a complex system?

Epimer separation is crucial in the field of analytical chemistry, separation science, and the pharmaceutical industry. No reported methods could separate simultaneously epimers or even isomers and remove other unwanted, co-existing, interfering substances from complex systems like herbal extracts. Herein, we prepared a heptapeptide-modified stationary phase for the separation of 1R,2S-(-)-ephedrine [(-)-Ephe] and 1S,2S-(+)-pseudoephedrine [(+)-Pse] epimers from Ephedra sinica Stapf extract and blood samples. The heptapeptide stationary phase was comprehensively characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The separation efficiency of the heptapeptide column was compared with an affinity column packed with full-length ß2-AR functionalized silica gel (ß2-AR column). The binding affinity of the heptapeptide with (+)-Pse was 3-fold greater than that with (-)-Ephe. Their binding mechanisms were extensively characterized by chromatographic analysis, ultraviolet spectra, circular dichroism analysis, isothermal titration calorimetry, and molecule docking. An enhanced hydrogen bonding was clearly observed in the heptapeptide-(+)-Pse complex. Such results demonstrated that the heptapeptide can recognize (+)-Pse and (-)-Ephe epimers in a complex system. This work, we believe, was the first report to simultaneously separate epimers and remove non-specific interfering substances from complex samples. The method was potentially applicable to more challenging sample separation, such as chiral separation from complex systems.

Using heteroaryl-lithium reagents as hydroxycarbonyl anion equivalents in conjugate addition reactions with (S,S)-(+)-pseudoephedrine as chiral auxiliary; enantioselective synthesis of 3-substituted pyrrolidines.

We have developed an efficient protocol for carrying out the stereocontrolled formal conjugate addition of hydroxycarbonyl anion equivalents to α,ß-unsaturated carboxylic acid derivatives using (S,S)-(+)-pseudoephedrine as chiral auxiliary, making use of the synthetic equivalence between the heteroaryl moieties and the carboxylate group. This protocol has been applied as key step in the enantioselective synthesis of 3-substituted pyrrolidines in which, after removing the chiral auxiliary, the heteroaryl moiety is converted into a carboxylate group followed by reduction and double nucleophilic displacement. Alternatively, the access to the same type of heterocyclic scaffold but with opposite absolute configuration has also been accomplished by making use of the regio- and diastereoselective conjugate addition of organolithium reagents to α,ß,γ,δ-unsaturated amides derived from the same chiral auxiliary followed by chiral auxiliary removal, ozonolysis, and reductive amination/intramolecular nucleophilic displacement sequence.

Influence of precursor solvent extraction on stable isotope signatures of methylamphetamine prepared from over-the-counter medicines using the Moscow and Hypophosphorous routes.

A number of methods of clandestine manufacture of methylamphetamine involve the extraction and subsequent reaction of pseudoephedrine hydrochloride with other essential chemicals. The precursor can be easily extracted from over-the-counter medication widely available in the UK and elsewhere. Essential chemicals such as iodine and red phosphorous are also readily available and can be extracted from iodine tinctures and matchboxes, respectively. This work reports the repetitive preparation of methylamphetamine using two popular routes (the Moscow and Hypophosphorous synthesis). The focus was on the extraction solvent used for isolation of the precursor chemical and any consequential isotopic variation which may arise in the final product. Six batches of methylamphetamine were prepared under precisely controlled conditions for each synthetic route and for each of three different precursor extraction solvents. Synthesis of the final product from laboratory grade precursor using the synthetic methods described was used as a template for comparison. The resultant IRMS data from all 48 prepared samples suggests some underlying trends in the identification of the synthetic route which may aid in the interpretation of IRMS data derived from clandestine samples.

Comparative single-dose pharmacokinetics of rasagiline in minipigs after oral dosing or transdermal administration via a newly developed patch.

1. A rasagiline transdermal patch was developed for the treatment of early and advanced Parkinson's disease. Relevant pharmacokinetic parameters of rasagiline obtained after transdermal administration to minipigs were compared with those of rasagiline after oral administration. 2. A total of 18 minipigs were randomly divided into three groups (six animals for each group). A single dose of 1 mg rasagiline tablet was orally administrated to one group. Meanwhile, single dose of 1.25 and 2.5 mg (2 and 4 cm(2)) rasagiline patches were given (at the postauricular skin) to the other two groups, respectively. The pharmacokinetic parameters such as plasma half-life (t1/2), time to peak plasma-concentration (Tmax), mean residence time (MRT), area under the curve (AUC(0-t)) were significantly (p < 0.05) different between transdermal and oral administrations. 3. The plasma half-life (t1/2) of rasagiline (1.25 mg patch: 11.8 ± 6.5 h, 2.5 mg patch: 12.5 ± 4.7 h) in minipig following transdermal administration was significantly prolonged as compared with that following the oral administration (1 mg tablet: 4.7 ± 2.5 h). The dose-normalized relative bioavailability of rasagiline patch in minipig were 178.5% and 156.4%, respectively, for 1.25 and 2.5 mg patches compared with 1 mg rasagiline tablet. The prolonged t1/2 and increased bioavailability of rasagiline patch suggested a possible longer dosing interval compared with oral tablet.

The advent of a new pseudoephedrine product to combat methamphetamine abuse.

BACKGROUND: The personal and societal effects of methamphetamine abuse are well documented. The ease of accessibility to methamphetamine and the quality of the "high" it produces makes the drug highly desired by its abusers. Over time, many methamphetamine users will also become methamphetamine cooks, where pseudoephedrine in over-the-counter cold products is converted to methamphetamine through a simple, albeit extremely dangerous, process. New laws limiting access to these products have had limited success. No existing commercial pseudoephedrine products offer significant impediments to slow or limit the extraction and conversion of pseudoephedrine in clandestine methamphetamine laboratories. OBJECTIVE AND METHODS: A new pseudoephedrine 30 mg tablet product using Impede technology (Nexafed®) to deter methamphetamine production has recently been introduced into the marketplace. Using methods designed to mimic clandestine laboratory processes, the ability of this product to disrupt extraction and conversion of pseudoephedrine to methamphetamine yet provide therapeutic effectiveness was evaluated. RESULTS: Impede™ technology tablets limited the extraction and/or conversion of pseudoephedrine to methamphetamine when compared to a commercially marketed pseudoephedrine product (Sudafed®). Nexafed® tablets were also shown to be bioequivalent to the same control product, thus ensuring therapeutic equivalence. CONCLUSIONS: With the advent of new pseudoephedrine products in the marketplace with features to limit the extraction and conversion of pseudoephedrine to methamphetamine, new tools are now available to minimize the clandestine manufacture of the drug and potentially limit its social impact.

[Simultaneous determination of ephedrine hydrochloride, D-pseudoephedrine and amygdalin in xiao'er pingchuan qutan granule by HPLC].

OBJECTIVE: To establish an HPLC method for the determination of ephedrine hydrochloride, D-pseudo-ephedrine and amygdalin in Xiao'er Pingchuan Qutan granule. METHOD: Pheny ether chromatographic column (4.6 mm x 250 mm, 5 microm) was adopted, with acetonitrile-0.1% phosphoric acid (containing 0.1% three ethylamine) (3:97) as the mobile phase. The UV detection wavelength was at 210 nm, with the flow rate of 1 mL x min(-1), and column temperature was at 35 degrees C. RESULT: The linearity of ephedrine hydrochloride, D-pseudo-ephedrine and amygdalin ranged between 0.078 60-3.144 microg (r = 1.000 0), 0.103 4-2.068 microg (r = 0.999 7) and 0.430 5-3.157 microg (r = 0.999 8), respectively. Their average recoveries were 98.46% (RSD 1.1%), 103.0% (RSD 1.5%) and 97.15% (RSD 2.1%), respectively. CONCLUSION: The method is simple, stable and reliable that it can be used to determine the content of ephedrine hydrochloride, D-pseudo-ephedrine and amygdalin in Xiao'er Pingchuan Qutan granule.

[Ligands of cholinesterases of ephedrine and pseudoephedrine structure].

The paper is a review of literature data on interaction of the mammalian erythrocyte acetylcholinesterase and blood serum butyrylcholinesterase with a group of isomer complex ester derivatives (acetates, propionates, butyrates, valerates, and isobutyrates) of bases and iodomethylates of ephedrine and its enantiomer pseudoephedrine. For 20 alkaloid monoesters, parameters of enzymatic hydrolysis are determined and their certain specificity toward acetylcholinesterase is revealed, whereas 5 diesters of iodomethylates of pseudoephedrine were hydrolyzed only by butyrylcholinesterase. The studied 20 aklaloid diesters and 10 trimethylammonium derivatives turned out to be non-competitive reversible inhibitors of acetylcholinesterase and competitive inhibitors of butyrylcholinesterase. The performed for the first time isomer and enantiomer analysis "structure-efficiency" has shown that in most cases it is possible to state the greater comlementarity of the catalytical surface of enzymes for ligands of the pseudoephedrine structure, such differentiation being realized more often at the reversible inhibition of enzymes. pseudoephedrine.

Amino acid bound surfactants: a new synthetic family of polymeric monoliths opening up possibilities for chiral separations in capillary electrochromatography.

By combining a novel chiral amino-acid surfactant containing an acryloyl amide tail, a carbamate linker, and a leucine headgroup of different chain lengths with a conventional cross-linker and a polymerization technique, a new "one-pot" synthesis for the generation of amino-acid based polymeric monolith is realized. The method promises to open up the discovery of an amino-acid based polymeric monolith for chiral separations in capillary electrochromatography (CEC). The possibility of enhanced chemoselectivity for simultaneous separation of ephedrine and pseudoephedrine containing multiple chiral centers and the potential use of this amino-acid surfactant bound column for CEC and CEC coupled to mass spectrometric detection are demonstrated.

Encapsulation of labetalol, pseudoephedrine in ß-cyclodextrin cavity: spectral and molecular modeling studies.

The absorption and fluorescence spectra of labetalol and pseudoephedrine have been studied in different polarities of solvents and ß-cyclodextrin (ß-CD). The inclusion complexation with ß-CD is investigated by UV-visible, steady state and time resolved fluorescence spectra and PM3 method. In protic solvents, the normal emission originates from a locally excited state and the longer wavelength emission is due to intramolecular charge transfer (TICT). Labetalol forms a 1:2 complex and pseudoephedrine forms 1:1 complex with ß-CD. Nanosecond time-resolved studies indicated that both molecules show triexponential decay. Thermodynamic parameters (ΔG, ΔH, ΔS) and HOMO, LUMO orbital investigations confirm the stability of the inclusion complex. The geometry of the most stable complex shows that the aromatic ring is deeply self included inside the ß-CD cavity and intermolecular hydrogen bonds were established between host and guest molecules. This suggests that hydrophobic effect and hydrogen bond play an important role in the inclusion process.

Separation mechanism of chiral impurities, ephedrine and pseudoephedrine, found in amphetamine-type substances using achiral modifiers in the gas phase.

A new mechanism is proposed that describes the gas-phase separation of chiral molecules found in amphetamine-type substances (ATS) by the use of high-resolution ion mobility spectrometry (IMS). Straight-chain achiral alcohols of increasing carbon chain length, from methanol to n-octanol, are used as drift gas modifiers in IMS to highlight the mechanism proposed for gas-phase separations of these chiral molecules. The results suggest the possibility of using these achiral modifiers to separate the chiral molecules (R,S) and (S,R)-ephedrine and (S,S) and (R,R)-pseudoephedrine which contain an internal hydroxyl group at the first chiral center and an amino group at the other chiral center. Ionization was achieved with an electrospray source, the ions were introduced into an IMS with a resolving power of 80, and the resulting ion clusters were characterized with a coupled quadrupole mass spectrometer detector. A complementary computational study conducted at the density functional B3LYP/6-31g level of theory for the electronic structure of the analyte-modifier clusters was also performed, and showed either "bridged" or "independent" binding. The combined experimental and simulation data support the proposed mechanism for gas-phase chiral separations using achiral modifiers in the gas phase, thus enhancing the potential to conduct fast chiral separations with relative ease and efficiency.

Role of pseudoephedrine as chiral auxiliary in the "acetate-type" aldol reaction with chiral aldehydes; asymmetric synthesis of highly functionalized chiral building blocks.

We have studied in depth the aldol reaction between acetamide enolates and chiral α-heterosubstituted aldehydes using pseudoephedrine as chiral auxiliary under double stereodifferentiation conditions, showing that high diastereoselectivities can only be achieved under the matched combination of reagents and provided that the α-heteroatom-containing substituent of the chiral aldehyde is conveniently protected. Moreover, the obtained highly functionalized aldols have been employed as very useful starting materials for the stereocontrolled preparation of other interesting compounds and chiral building blocks such as pyrrolidines, indolizidines, and densely functionalized ß-hydroxy and ß-amino ketones using simple and high-yielding methodologies.

High-resolution mass-selective UV spectroscopy of pseudoephedrine: evidence for conformer-specific fragmentation.

Using resonance-enhanced two-photon ionization spectroscopy with mass resolution of jet-cooled molecules, a low-resolution S(1) ← S(0) vibronic spectrum of pseudoephedrine was recorded at the mass channels of three distinct fragments with m/z = 58, 71, and 85. Two of the fragments, with m/z = 71 and 85, are observed for the first time for this molecule. The vibronic spectra recorded at different mass channels feature different patterns, implying that they originate from different conformers in the cold molecular beam, following conformer-specific fragmentation pathways. Highly resolved spectra of all prominent vibronic features were measured, and from their analysis based on genetic algorithms, the molecular parameters of the conformers giving rise to the respective bands have been determined. Comparing the experimental results with those obtained from high-level ab initio quantum chemistry calculations, the observed prominent vibronic bands have been assigned to originate from four distinct conformers. The conformers are separated into two groups that have different fragmentation pathways determined by the different intramolecular interactions.

Simultaneous chiral separation of methylamphetamine and common precursors using gas chromatography/mass spectrometry.

Methylamphetamine, ephedrine, and pseudoephedrine were derivatized using trifluoroacetic anhydride and enantiomers of each were analyzed using gas chromatography coupled to mass spectrometry (GC/MS) fitted with a γ-cyclodextrin (Chiraldex™ G-PN) chiral column. A temperature-programmed method was developed and optimized and the results compared with those obtained using a previously published isothermal GC method applied to GC/MS analysis. Trifluoroacetylated 3-(trifluoromethyl)phenethylamine hydrochloride was used as an internal standard, and mass fragmentation patterns are proposed for all derivatives analyzed. Qualitative validation of the optimized chromatographic conditions was completed in accordance with the guidelines published by the United Nations Office on Drugs and Crime (UNODC). Under conditions of repeatability and reproducibility, the method gave relative retention times with a relative standard deviation of less than 0.02% for all six analytes of interest. This surpasses the UNODC's acceptance criteria of 2% for validation of qualitative precision. Ephedrine and pseudoephedrine are common precursors in the clandestine manufacture of methylamphetamine. Seizures of illicit methylamphetamine therefore often contain mixtures of these optically active compounds. The simultaneous enantioseparation of these compounds to produce a profile would provide valuable information to law enforcement agencies regarding the provenance of a methylamphetamine seizure.