34391-04-3 Usage
Description
Salbutamol, also known as Albuterol, is a bronchodilator medication that works by easing muscle tension in the airways adjoining the lungs and enhancing the flow of air circulating through the lungs. It is a short-acting medication used in the treatment of acute bronchopulmonary disorders, including chronic obstructive pulmonary disorders (COPD), and chronic instances of bronchospasm resulting from acute bronchitis and bronchial asthma. Salbutamol exhibits 29 times more selectivity for beta2 receptors compared to beta1 receptors, providing higher specificity for adrenergic receptors located in the heart. The medication consists of a racemic combination of Sand R-isomers, with the R-isomer demonstrating a higher affinity (about 150 times more) than the S-isomer, which is directly linked to increased toxicity. This has also influenced the development of Levalbuterol.
Uses
1. Used in Respiratory Applications:
Salbutamol is used as a bronchodilator for the prevention and treatment of bronchospasm. It is most commonly administered in its inhaled form by metered-dose inhaler (1–2 puffs of 100μg each) or via nebulizer in more severe cases of bronchospasm (2.5–5mg). In patients with life-threatening asthma, it may be administered intravenously as both a bolus (250μg) and infusion (3–20μg/min). Intravenous administration requires cardiac monitoring due to the potential for tachyarrhythmias.
2. Used in Emergency Medicine:
Salbutamol is used in the management of hyperkalemia, temporarily driving potassium ions (K+) intracellularly via stimulation of the Na+–K+ ATPase pump.
3. Used in Pharmaceutical Industry:
Salbutamol is used in the composition and development of methods to reduce beta-agonist-mediated tachyphylaxis, which is the rapid decrease in the effectiveness of a drug due to repeated administration.
4. Used in Levalbuterol Development:
Levalbuterol, the single R-enantiomer version of racemic albuterol (salbutamol), was launched in the US for the treatment or prevention of bronchospasm in patients with reversible obstructive airway disease. The R-isomer retains the desired bronchodilating effect of the racemic mixture with a lower incidence of beta-mediated side effects such as pulse rate increase, tremor, and decrease in blood glucose and potassium levels. A pivotal clinical trial demonstrated a greater improvement in lung function for the pure enantiomer Levalbuterol.
Brand Name: Xopenex
Indications
Salbutamol is indicated for the treatment of chronic asthma, maintenance of asthma, bronchitis, chronic obstructive pulmonary disease and uncomplicated preterm labor.
Salbutamol is an adrenergic bronchodilator, which is a class of medications that are inhaled through the mouth to ease tension in the bronchial tubes and the lungs. Such drugs also relieve shortness of breath, coughs, breathing complications, and wheezing by enhancing the circulation of air through the air passages.
Contraindications
Salbutamol is contraindicated in patients who are hypersensitive to any of its formulation ingredients. The drug should not be prescribed for children under 4 years, pregnant women and elderly patients who are at high risk of developing kidney, liver and heart problems which are age-related.
Dosage Information
For prevention or treatment of bronchospasm, children above 4 years and adults should inhale (aerosol & powder) 2 puffs every 4-6 hours as required. For prevention of training induced-bronchospasm, children above 4 years and adults should inhale (aerosol & powder) 2 puffs 15-30 minutes before the training session. For prevention and treatment of bronchospasm, children above 12 years and adults should take 2.5mg 3-4 times per day as a solution in a nebulizer, where children 2-12 years should take 0.63-1.25mg 3-4 times per day in a nebulizer.
Pharmacodynamics
Salbutamol, which is a selective beta2-receptor inhibitor has a structure that resembles that of terbutaline, and it is widely indicated as a bronchodilator for the management of asthma and other acute obstructive airway infections. Levalbuterol, the R-isomer influences bronchodilation whereas the S-isomer enhances bronchial reactivity. Levalbuterol comprises the pure form of the R-enantiomer. Levalbuterol and Sepracor manufacturers maintain that the existence of the R-enantiomer results in less severe side effects.
Mechanism of Action
Salbutamol is a beta2-adrenergic inhibitor hence it stimulates the beta2-adrenergic receptors. The bond between the drug and the beta2-receptors releases tension in the smooth muscles of the bronchi and the lungs. Salbutamol enhances the secretion of cyclic AMP by restoring adenylate cyclase, hence the drug-action is effectuated by cAMP. The stimulated cAMP enhances the functionality of cAMP-dependent Kinase A, and further suppresses the phosphorylation of myosin which reduces calcium levels within the cell. A reduction in calcium levels within the cell results in relaxation of the smooth muscles and bronchodilation. In addition, the drug suppresses the detachment of bronchorestricting agents from mast cells, suppresses microvascular leakage, and facilitates mucociliary clearance.
Drug Interactions
Salbutamol may be prescribed alongside other medications depending on the condition of the patient and the effectiveness of the drug combination. However, Salbutamol may enhance the occurrence of certain side effects if it is combined with Trimipramine, Tianeptine, Opipramol, Protriptyline, Nortriptyline, Melitracen, Lofepramine, Levalbuterol, Imipramine, Doxepin, Dibenzepin, Desipramine, Clomipramine, Atomoxetine, Amoxapine, Amitriptylinoxide, Amitriptyline and Amineptine. This list is not all-inclusive hence one should also consult their doctor for dose adjustments.
Route of Elimination
About 72% of inhaled Salbutamol is eliminated in urine 24 hours after inhalation, where 28% comprises the unaltered form of the drug and 44% as a metabolite. Salbutamol has a half-life of 1.6 hours.
Precautions
Salbutamol should not be used in concurrent treatment with other inhaled medications such as terbutaline, pirbuterol, metaproterenol, levalbuterol and isoproterenol. The drug may result in paradoxical bronchospasm which may be life-threatening.
Side Effects
Common side effects associated with salbutamol include shaking/trembling of the feet or hands, racing, irregular or fast pounding heartbeat. Less common side effects associated with the drug may include unusual weakness, chest tightness, swollen, painful or tender lymph nodes in the groin, neck or armpit, stomach pains, sore throat, runny nose, redness of the arms, neck, face and the upper chest, puffiness of the face, eyelids or the tongue, nausea, lower back pain, loss of appetite, hoarseness, skin rash, hives or itching, fever, diarrhoea, laboured breathing, difficulty in swallowing, coughs, chills, chest pains, bloody urine and bladder pain. In addition, more common side effects may also include congestion and voice changes.
Manufacturing Process
Preparation of 5-glyoxyloyl-salicylic acid methyl ester hydrate using aqueous
HBrTo a 3-neck flask immersed in an oil bath containing a solution of 40 g (0.206
mole) methyl 5-acetylsalicylate in 6 ml methylene chloride is charged with 82
ml of isopropanol. The solution is distilled to remove excess methylene
chloride. When the internal temperature reaches 77°C, 126 ml (1.77 mole or
8.6 equivalents) of DMSO is added to the reaction mixture and the
temperature of the mixture is increased to a temperature of 85° to 90°C.
Then 33 ml (0.29 mole or 1.4 equivalents) of HBr (aqueous, 48%) is added to
the mixture over a period of 20 minutes (exothermic), and the bath
temperature is maintained at 95° to 100°C. As the addition of HBr nears
completion distillation is initiated and dimethysulfide and isopropanol are
distilled off. The mixture is stirred and the volume of the distillate monitored.
After distillation of 82 ml of solvent, 20 ml of isopropanol is added slowly to
maintain a steady rate of distillation. After the reaction completed asdetermined by high performance liquid chromatography (HPLC), the reaction
mixture is quenched with 70 ml of 2.4 N H2SO4, the temperature of the
reaction mixture is allowed to drop to 75°C and residual isopropanol is
distilled off under vacuum. After a total of 165 ml distillate is collected, the
title compound begins to precipitate. A mixture of 30 ml of acetonitrile and 70
ml of water is added slowly at 75°C with stirring. After 30 minutes of stirring,
the reaction mixture is cooled to 15°C over a period of 90 minutes to
complete the precipitation. The reaction mixture is filtered and the cake is
washed with three 300 ml portions of water. The cake is dried in a draft oven
at 50°C for 16 hours to give 39.5 g of the title compound (85% yield).Preparation of albuterol from 5-glyoxyloyl-salicylic acid methyl esterTo a solution of 5-glyoxyloylsalicylic acid methyl ester hydrate (50 g, 0.221
mol) in ethylene glycol diethyl ether, 440 mL is added tertiary butylamine
(16.2 g, 0.221 mol) at room temperature. The resulting light orange solution
is stirred for 5 min until a clear solution is formed. The clear solution is then
heated to reflux. Water and DME are distilled off azeotropically. After a total of
200 ml of distillate are collected, the solution is cooled to 25°C. The reaction
mixture is slowly added to a solution containing 49 mL (0.49 mol) of 10.0 M
borane-dimethyl sulfide in 220 mL of ethylene glycol diethyl ether (DME) at
70°C. The resulting reaction mixture is further refluxed for 2.5 hrs. After the
reaction is completed as monitored by HPLC, excess DME is removed via
vacuum distillation. The residue containing complexes of boron and
arylethanolamine is subsequently cooled to 0°C. Quenching of the residue
with 300 mL methanol gives the methylborate of arylethanolamine. The borate
is then removed by azeotropic distillation as trimethylborate, leaving behind
the desired arylethanolamine in the reaction mixture. An additional 300 ml of
methanol and acetic acid (85 mL) are added to ensure the complete removal
of trimethylborate via vacuum distillation to near dryness. The residue
containing the boron-free arylethanolamine is cooled to 25°C and
concentrated sulfuric acid (10.4 g, 0.221 mole) in water (64 mL) is added
following by 570 ml of isopropyl alcohol. Albuterol sulfate is precipitated out
as a white solid. After the reaction mixture is stirred at room temperature for
12 hrs and 0°C for 30 min the albuterol sulfate is filtered, washed with
isopropyl alcohol (two 50 mL portions) and dried at 50°C for 12 hrs to give
49.75 g of the title compound (78% yield) as racemate.The optically pure albuterol may be prepared by resolving a mixture of
enantiomers methyl benzoate albuterol precursors which prepared by
procedures well known to persons skilled in the art. The starting material 4-
benzyl albuterol is commercially available from Cipla (Bombay, India).(-)-D-Dibenzoyltartaric acid (D-DBTA) (32.2 g, 90 mmol, 1.0 eq) is added to a
hot solution of racemic 4-benzyl albuterol (29.6 g, 90 mmol, 1.0 eq) in 180
mL of anhydrous denatured ethanol (type 3A, denatured with 5 vol % 2-
propanol). The resulting solution is refluxed for 15 min and cooled to room
temperature over 40 min and seeded with 99% ee (R)-4-benzyl albuterol DDBTA salt. The mixture is cooled to 5°-10°C and stirred for 1 hour. The white
solid is collected by filtration and dried at 40°C and 28 inches of Hg for 1 hour
to give (R)-4-benzyl albuterol D-DBTA salt (31.8 g, 50% yield, 83.6% ee).
The solid is redissolved in 240 mL of ethanol at 55°-60°C and the solution is
cooled to room temperature and stirred at room temperature for 2 hours and
at 0°-5°C for 1 hour. The resulting solid is collected by filtration and dried at40°C and 28 inches of Hg for 2 hours as (R)-4-benzyl albuterol D-DBTA salt
(22.9 g, 37.1% yield, 99.3% ee). The salt (22.9 g) is then treated with 204
mL of 5 wt % aq. Na2CO3 solution in 570 mL of ethyl acetate. The solid is
worked-up, and recrystallization from 30 mL of ethyl acetate and 30 mL of nheptane gives optically pure (R)-4-benzyl albuterol free base as a white
powder (10.1 g, 34.1% yield from racemic compound 99.6% ee and 99.8%
purity).A mixture of (R)-4-benzyl albuterol as a free base (3.2 g, 9.73 mmol) and
10% Pd/C (0.64 g) in 24 mL of ethanol (denatured with 5 vol % 2-propanol)
is shaken on a Parr-hydrogenator under 50 psi of hydrogen at room
temperature for 3 hours. The catalyst is removed by filtration and the filtrate
is concentrated to ca. 9 mL in volume containing crude (R)-albuterol and
treated with anhydrous HCl in ether (1.0 M, 9.5 mL, 0.98 eq) at 0°-5°C. After
30 min at room temperature, 9 mL of methyl t-butyl ether (MTBE) is added,
the resulting mixture is stirred at room temperature for 30 min and at 0°-5°C
for 2 hours. The white solid (R)-albuterol hydrochloride is collected by
filtration and recrystallized from 25 mL of ethanol and 12.5 mL of MTBE to
give pure (R)-albuterol hydrochloride (2.17 g, 80.9% yield, 99.6% purity),
white powder.
Therapeutic Function
Bronchodilator
Clinical Use
Beta2
-adrenoceptor agonist:
Reversible airways disease
Drug interactions
Potentially hazardous interactions with other drugs
Increased risk of hypokalaemia when diuretics,
theophylline or large doses of corticosteroids are
given with high doses of salbutamol.
Antihypertensives: acute hypotension with IV
infusion of salbutamol and methyldopa.
Metabolism
Salbutamol is subject to first-pass metabolism in the
liver and possibly in the gut wall but does not appear to
be metabolised in the lung; the main metabolite is the
inactive sulphate conjugate.
Salbutamol is rapidly excreted, mainly in the urine, as
metabolites and unchanged drug; a smaller proportion is
excreted in the faeces.
Check Digit Verification of cas no
The CAS Registry Mumber 34391-04-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,4,3,9 and 1 respectively; the second part has 2 digits, 0 and 4 respectively.
Calculate Digit Verification of CAS Registry Number 34391-04:
(7*3)+(6*4)+(5*3)+(4*9)+(3*1)+(2*0)+(1*4)=103
103 % 10 = 3
So 34391-04-3 is a valid CAS Registry Number.
InChI:InChI=1/C13H21NO3/c1-13(2,3)14-7-12(17)9-4-5-11(16)10(6-9)8-15/h4-6,12,14-17H,7-8H2,1-3H3
34391-04-3Relevant articles and documents
Preparation and characterization of a new open-tubular capillary column for enantioseparation by capillary electrochromatography
Li, Yingjie,Tang, Yimin,Qin, Shili,Li, Xue,Dai, Qiang,Gao, Lidi
, p. 283 - 292 (2019/02/05)
In order to use the enantioseparation capability of cationic cyclodextrin and to combine the advantages of capillary electrochromatography (CEC) with open-tubular (OT) column, in this study, a new OT-CEC, coated with cationic cyclodextrin (1-allylimidazolium-β-cyclodextrin [AI-β-CD]) as chiral stationary phase (CSP), was prepared and applied for enantioseparation. Synthesized AI-β-CD was characterized by infrared (IR) spectrometry and mass spectrometry (MS). The preparation conditions for the AI-β-CD-coated column were optimized with the orthogonal experiment design L9(34). The column prepared was characterized by scanning electron microscopy (SEM) and elemental analysis (EA). The results showed that the thickness of stationary phase in the inner surface of the AI-β-CD-coated columns was about 0.2 to 0.5?μm. The AI-β-CD content in stationary phase based on the EA was approximately 2.77?mmol·m?2. The AI-β-CD-coated columns could separate all 14 chiral compounds (histidine, lysine, arginine, glutamate, aspartic acid, cysteine, serine, valine, isoleucine, phenylalanine, salbutamol, atenolol, ibuprofen, and napropamide) successfully in the study and exhibit excellent reproducibility and stability. We propose that the column, coated with AI-β-CD, has a great potential for enantioseparation in OT-CEC.
(R)- albuterol hydrochloride asymmetric preparation method (by machine translation)
-
, (2017/08/25)
The present invention relates to a high-efficient chiral catalyst synthesis of (R)- albuterol hydrochloride the asymmetric synthesis of the new method, the synthesis step includes: 1) salicylaldehyde with a halo of acetyl halogen crafts acylation reaction halo; 2) obtained after the the halogenated ketone uses unclebutylamine amine solution obtained after hydrolysis to the protection of the salicylaldehyde aminoketone; 3) this aminoketone in chiral amino alcohol derivative of the chiral borane the presence of a catalyst, is reduced to (R)- albuterol crude product, then the purified hydrochloric salt to obtain the high purity of the (R)- albuterol hydrochloride. (by machine translation)
Comparison of three S-β-CDs with different degrees of substitution for the chiral separation of 12 drugs in capillary electrophoresis
Wang, Zhaokun,Zhang, Qiongwen,Luo, Linda,Sun, Tiemin,Guo, Xingjie
, p. 558 - 565 (2017/08/26)
Three kinds of sulfated β-cyclodextrin (S-β-CD), including a single isomer, heptakis-6-sulfato-β-cyclodextrin (HS-β-CD), degree of substitution (DS) of 7, which was synthesized in our laboratory and another two commercialized randomly substituted mixtures, a sulfated β-cyclodextrin with DS of 7 to 11, as well as a highly sulfated-β-cyclodextrin with DS of 12 to 15, were used for the enantioresolution of 12 drugs (the β-blockers, phenethylamines, and anticholinergic agents) in capillary electrophoresis. The enantioseparation under varying concentrations of S-β-CD and background electrolyte pH were systematically investigated and compared. Based on the experimental results, the effect of the nature of S-β-CD and analyte structure on the enantioseparation is discussed.