Mechlorethamine Hydrochloride
Click to View Image
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.
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.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Feiwen Mao, M.S.
(MDOOD05) Monograph Development-Ophthalmics Oncologics and Dermatologicals
Reference Standards Lili Wang, Technical Services Scientist
USP32–NF27 Page 2857
Pharmacopeial Forum: Volume No. 29(3) Page 636