Mechlorethamine Hydrochloride
(me'' klor eth' a meen hye'' droe klor' ide).
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C5H11Cl2N·HCl 192.51

Ethanamine, 2-chloro-N-(2-chloroethyl)-N-methyl-, hydrochloride.
2,2¢-Dichloro-N-methyldiethylamine hydrochloride [55-86-7].
» Mechlorethamine Hydrochloride contains not less than 97.5 percent and not more than 100.5 percent of C5H11Cl2N·HCl, calculated on the anhydrous basis.
Packaging and storage— Preserve in tight, light-resistant containers.
Labeling— The label bears a warning that great care should be taken to prevent inhaling particles of Mechlorethamine Hydrochloride and exposing the skin to it.
USP Reference standards 11
USP Mechlorethamine Hydrochloride RS Click to View Structure
B: Transfer 100 mg to a test tube containing 1 mL of sodium thiosulfate solution (prepared by dissolving 1 g of sodium thiosulfate and 100 mg of sodium carbonate in 40 mL of water), shake, allow to stand for 2 hours, then add 1 drop of iodine TS: the color of free iodine remains.
Melting range 741: between 108 and 111.
pH 791: between 3.0 and 5.0, in a solution (1 in 500).
Water, Method I 921: not more than 0.4%.
Ionic chloride content— Dissolve about 30 mg, accurately weighed, in 30 mL of water contained in a beaker. Add 5 mL of nitric acid and stir. Titrate with 0.02 N silver nitrate VS to a potentiometric endpoint, using a silver combination electrode. Perform a blank determination (see Titrimetry 541), and make any necessary correction. Each mL of 0.02 N silver nitrate is equivalent to 0.709 mg of ionic chloride: not less than 18.0% and not more than 19.3% of ionic chloride is found.
Assay— Transfer about 100 mg of Mechlorethamine Hydrochloride, accurately weighed, to a 125-mL conical flask. Add 100 mg of sodium bicarbonate and 20.0 mL of 0.1 N sodium thiosulfate VS. Allow to stand for 2½ hours, add 3 mL of starch TS, and titrate the excess sodium thiosulfate with 0.1 N iodine VS. Each mL of 0.1 N sodium thiosulfate is equivalent to 9.626 mg of C5H11Cl2N·HCl.
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Monograph Feiwen Mao, M.S.
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(SM32010) Monographs - Small Molecules 3
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USP35–NF30 Page 3775
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