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Toluene.

Aluminium oxide for column chromatography, 80 to 200 mesh, alkaline, Brockman activity 1. To 100 parts of the aluminium oxide add 6 parts of powdered magnesium hydroxide. Shake in a screw-cap bottle to mix, add 8 parts of water, and mix until free from lumps.

Sand; acid washed.

Dimethylformamide solution, 95% v/v.

Dimethylformamide solution, 50% v/v.

Phenylhydrazine, hydrochloride solution: shake 0.25±0.005g of phenylhydrazine hydrochloride in 25ml of water, add 25ml of concentrated hydrochloric acid, and shake to dissolve the solid, filtering if necessary. Prepare this reagent immediately before use.

Methylbenzethonium hydroxide solution: about 10% in methanol.

Nifursol standard solution: weigh, to the nearest 0.1mg, 25mg of pure nifursol into a 100ml graduated flask, add 5ml of 95% v/v dimethylformamide solution (3.4), and mix until all the solid has dissolved. Dilute to the mark with methanol. Prepare this solution freshly each day.