Methylbromide salt

Propantheline Propanetheline, A-methyl-iV-(l-methylethyl)-iV-[2-[(9/f-xanthen-9-ylcarbonyl) oxy]ethyl]-2-propanaminium bromide (14.1.11), is synthesized by reacting xan-then-9-carboxylic acid chloride with 2-di-MO-propylaminoethanol, giving the ester (14.1.10), which upon reaction with methylbromide turns into the quaternary salt, propantheline (14.1.11) [12,13]. 

Homatropine Methylbromide, USP. Homatropini methylbromidc. 3a-hydroxy-8-methyl-1 aN.Sa/f-tropanium bromide mandelate (Novatropine, Mesopin), occurs as a bitter. white, odorless powder and is affected by light. Tbe compound is readily soluble in water and alcohol but insoluble in ether. The pH of a 1% solution is 5.9 and that of a 10% solution is 4.5. Although a solution of the compound yields a precipitate with alkaloidal reagents, such as mercuric potassium iodide test solution, addition of alkali hydroxides or carbonates does not cause the precipitate thil occurs with nonquatemary nitrogen salts (c.g.. atropine, homatropine). 

Clidinium bromide is synthesized by the reaction scheme shown in Figure 6. 3-Quinuclidinol is reacted with methyl benzilate to form the ester. The ester is then reacted with methylbromide to form the quaternary salt, clidinium bromide (10). 

The assay of the alkaloidal base in this salt follows the conventional lines of extraction with chloroform from ammoniacal solution and titration of the dried alkaloid using methyl red as indicator. 1 ml 0 05N acid = 0 01781 g CieHgjOaNjHBr. It can be assayed by non-aqueous titration (p. 792) using 0 5 g. 1 ml 0 1 N perchloric acid — 0 03563 g. Homatropine methylbromide, Ci7H2403NBr, Mol. Wt. 370 3 can also be assayed by this method. 1 ml 0 1 N perchloric acid == 0 03703 g. 

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