Methacholine chloride

Acetyl-P-methylcholine chloride [62-51-1/, commonly called methacholine chloride, is a parasympathornimetic bronchoconstrictor with clinical efficacy in bronchial asthma (45,46). 

O-Acetyl-p-methylcholine chloride [Methacholine chloride, Amechol, Provocholine, 2-acetoxypropyl-ammonium chloride] [62-51-1] M 195.7, m 170-173", 172-173". It forms white hygroscopic needles from Et20 and is soluble in H2O, EtOH and CHCI3. It decomposes readily in alkaline solns and slowly in H2O. It should be handled and stored in a dry atmosphere. The bromide is less... 

Metanilic acid, all6 Methacholine chloride, a49 Methacrolein, m27 Methacrolein diacetate, m32 Methallyl alcohol, m400 Methallyl chloride, cl82... 

Materials Required Methacholine chloride 0.4 g glacial acetic acid 50 ml mercuric acetate solution 10 ml 0.1 N perchloric acid and crystal violet solution. 

Calculations The percentage of methacholine chloride in the sample may be calculated by the following expression ... 

Mesyl chloride, m32 Metanilic acid, all9 Methacholine chloride, a49 Methacrolein, m24 Methallyl alcohol, m3 85 Methallyl chloride, cl64... 

Quaternary compounds (substituted ammonium salts, methacholine chloride, mepenzolate bromide, phospholine iodide, etc.) approximately 10%... 

Provocholine methacholine chloride, proxazocaine hydrochloride — pramoxine. 

Methacholine Chloride. 2-(Acetyloxy -N,N,N-tri-mct hyl-1 -propana min i um chloride acetyl-0-methyicholine chloride O-acetyI-d-methylcholine chloride (2-hydroxy-propyl)trimethylammonium chloride acetate (2 Jacetoxy-propyl)trimethylammonium chloride trimethy] -i -acetoxy -propylammonium chloride Amechol Provocholine. C Hia-aNO, mol wt 195.69. C 49.10%. H 9.27%, Cl 18 ] 2%. N 7.16%, O 16.35%. Parasympathomimetic bronchoconstric-tor. Prepn from trimethylacetonylammonium chloride R. T. Major, J. K. Cline, L.S, pat. 2,040,146 (1936 to Merck Co.). Mechanism of ganglionic blockade in cats R. L. 

Carbamylcholine and Methacholine. The potential dependence of A/ / Ro in the cases of carbamylcholine chloride and methacholine chloride (Fig. 42) is similar to that for acetylcholine chloride. Thus the adsorption behavior of these molecules is probably similar to that of acetylcholine. 

A few typical examples of medicinal compormds bleonging to this category are discussed below acetylcholine chloride bethanechol chloride carbachol methacholine chloride pilocarpine nitrate, etc. 

Methacholine, acetyl (3-methylcholine, (see previous structure and SAR discussion) is marketed as the racemic mixture. It is a selective muscarinic agonist with very little activity at nicotinic receptors. Although methacholine chloride is marketed as the racemic mixture, the S-(+)-enantiomer is 240-fold more potent than the R-(-)-isomer at muscarinic receptors. In addition, AChE hydrolyzes S-(+)-methacholine at approximately 54% the rate of acetylcholine, whereas the R-(-)-enantiomer is a weak inhibitor. Methacholine chloride is used via inhalation for the diagnosis of asthma. The resulting bronchospasm may be relieved with bronchodilators. Methacholine chloride is available as a powder that is reconstituted for inhalation. 

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