(bue sul' fan).
» Busulfan contains not less than 98.0 percent and not more than 100.5 percent of C6H14O6S2, calculated on the dried basis.
Packaging and storage Preserve in tight containers.
Labeling The label bears a warning that great care should be taken to prevent inhaling particles of Busulfan and exposing the skin to it.
A: Fuse about 100 mg with about 100 mg of potassium nitrate and a pellet of potassium hydroxide weighing approximately 250 mg. Cool, dissolve the residue in water, acidify with 3 N hydrochloric acid, and add a few drops of barium chloride TS: a white precipitate is formed.
B: To 100 mg add 10 mL of water and 5 mL of 1 N sodium hydroxide. Heat until a clear solution is obtained: an odor characteristic of methanesulfonic acid is perceptible.
C: Cool the solution obtained in Identification test B, and divide it into two equal portions. To one portion add 1 drop of potassium permanganate TS: the purple color changes to violet, then to blue, and finally to emerald-green. Acidify the second portion of the solution with 2 N sulfuric acid, and add 1 drop of potassium permanganate TS: the color of the permanganate is not discharged.
Melting range 741: between 115 and 118.
Loss on drying 731 Dry it in vacuum at 60 to constant weight: it loses not more than 2.0% of its weight.
Residue on ignition 281: not more than 0.1%.
Assay Transfer about 80 mg of Busulfan, accurately weighed, to a 250-mL conical flask. Add about 30 mL of water, swirl, add phenolphthalein TS, and neutralize with 0.05 N sodium hydroxide. Connect the flask to a reflux air condenser, and boil the mixture gently for not less than 30 minutes, adding water occasionally to maintain the volume. Cool to room temperature, add phenolphthalein TS, and titrate with 0.05 N sodium hydroxide VS. Each mL of 0.05 N sodium hydroxide is equivalent to 6.158 mg of C6H14O6S2.