Decongestant, ephedrine

Starting with two chiral centres, there should, therefore, be four stereoisomers, and this is nicely exemplified by the natural alkaloid (-)-ephedrine, which is employed as a bronchodilator drug and decongestant. Ephedrine is (li ,25)-2-methylamino-l-phenylpropan-l-ol, so has the structure and stereochemistry shown. 

Nasal decongestants (ephedrine, Tachycardia Nonselective activation of... 

Explain how you would distinguish spectroscopically between the controlled substances meth-amphetamine, 26.36, methcathinone, 26.37, and the decongestant ephedrine, 26.38. 

Many alkaloids have pronounced biological properties, and a substantial number of the pharmaceutical agents used today are derived from naturally occurring amines. As a few examples, morphine, an analgesic agent, is obtained from the opium poppy Papaver somnifemm. Cocaine, both an anesthetic and a central nervous system stimulant, is obtained front the coca bush Erythroxylon coca, endemic to upland rain forest areas of Colombia, Ecuador, Peru, Bolivia, and western Brazil. Reserpine, a tranquilizer and antihypertensive, comes from powdered roots of the semitropical plant Rauwolfia serpentina. Ephedrine, a bronchodilator and decongestant, is obtained front the Chinese plant Ephedra sinica. 

Additive sympathomimetic effects may develop when decongestants are administered with other sympathomimetic drug s (see Chap. 22). Use of the nasal decongestants with the MAOIs may cause hypertensive crisis. Use of a decongestant with beta-adrenergic blocking dragp may cause hypertension or bradycardia. When ephedrine is administered with theophylline, the patient is at increased risk for theophylline toxicity. 

Ephedrine and pseudoephediine are a vasodilator and decongestant respectively used widely in the treatment of asthma and the symptoms of colds and influenza. These pharmaceuticals were derived originally fi om the plant Ephedra sinica and used in traditional Chinese medicinal preparations. Although some are still produced fi om such sources, the major production is via a fermentation process followed by a chemical catalytic reaction. As shown in Figure 1, the intermediate / -phenylacetylcarbinol (PAC) is produced by decarboxylation of pyruvate followed by ligation to benzaldehyde. 

Schematic profile of the titration curve for a weak base B titrated with hydronium ions. The pH values are those for titration of ephedrine, a weak base that is the active ingredient in many decongestants.

Ephedrine, a weak base, is the active ingredient in many commercial decongestants. To analyze a sample of ephedrine dissolved in 0.200 L of water, a chemist carries out a titration with 0.900 M HCl, monitoring the pH continuously. The data obtained in this titration are shown in Figure 18-6. Calculate Zj, for ephedrine and determine the pH of the solution at the stoichiometric point. 

Ephedrine An amphetamine-like drug used as a nasal decongestant. 

Ephedrine is the main alkaloid produced in the roots of Ephedra sinica, preparations of which have found medical application in China for at least 5000 years. It was first purified from its natural source in 1887, and its chemical synthesis was achieved in 1927. It was initially used in cardiovascular medicine, but subsequently found wider application in the treatment of mild hayfever and asthma. It is also used as a nasal decongestant and cough suppressant. 

Manage rebound congestion by stopping ephedrine one nostril at a time, substitute systemic decongestant and/or nasal steroid... 

Ephedrine was originally isolated as the active agent present in plant extracts used in ancient Chinese medicine for respiratoiy ailments. As long ago as 1921 the formation of optically active phenylacetyl carbinol (PAC) from benzaldehyde and pyravate by brewers yeast and cell-free yeast extracts was reported. The PAC can then be reductively animated to produce optically active L-ephedrine (Figure 4.18). L-Ephedrine is widely used in the treatment of asthma and hay fever as a bronchodilating agent and decongestant. 

Ephedrine is found in the ephedra plant (Ephedra sinica— the Chinese herb Ma Huang). It is used as a nasal decongestant... 

Ephedrine is useful for the treatment of chronic and moderate type of bronchial asthma, used as nasal decongestant and as a mydriatic without cycloplegia. It is also useful in preventing ventricular asystole in Stokes Adams syndrome. It is also used in narcolepsy, however amphetamines are the drug of choice. 

Ephedrine has not been extensively studied in humans despite its long history of use. Its ability to activate 3 receptors probably accounted for its earlier use in asthma. Because it gains access to the central nervous system, it is a mild stimulant. Ingestion of ephedrine alkaloids contained in ma huang has raised important safety concerns. Pseudoephedrine, one of four ephedrine enantiomers, has been available over the counter as a component of many decongestant mixtures. However, the use of pseudoephedrine as a precursor in the illicit manufacture of methamphetamine has led to restrictions on its sale. 

N.A. Ephedra nevadensis Wats. Pseudoephedrine, 1-ephedrine, d-pseudoephedrine.100 A decongestant and asthma remedy, for hypertension, hay fever. 

EXTENSIONS AND COMMENT ARY Here is another example of the presentation of a compound for which there has not yet been an effective level determined. Why For a very good reason. This is an example of a whole class of compounds that I have called the pseudos, or the -compounds. Pseudo- as a prefix in the literary world generally stands for false. A pseudopod is a thing that looks like a foot, but isn t one. A pseudonym is a fictitious name. But in chemistry, it has quite a different meaning. If something has a common name, and there is a second form (or isomer, or shape, or orientation) that is possible and it doesn t have a common name, it can be given the name of the first form with a pseudo- attached. Ephedrine is the erythro-isomer of N-methyl-13-hydroxyamphetamine. There is a second stereoisomer, the threo- isomer, but it has no trivial name. So it is called pseudoephedrine, or the Sudafed of sinus decongestant fame. 

Ephedrine sulfate, Kondon s Nasal, Pretz-D, or Vicks Vatronol is classified as a decongestant and vasopressor. 

Nasal Decongestants for Systemic Use Sympathomimetics (pseudoephedrine, phenylpropanolamine, phenylephrine) and structural analogues (epinephrine, ephedrine)... 

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