Related entry: Black pepper
C4H10N2 = 86.1.
Synonyms.—Diethylene-diamine; Ethylenimine; Dispermin; Hexahydropyrazine.
Piperazidine, (C2H4NH)2, is an organic base closely allied to the natural alkaloids.—It may be prepared by the action of ammonia on ethylene bromide or chloride. It is also known under the trade-name Piperazine. It occurs in the form of colourless, glassy, lustrous, deliquescent, tables, absorbing carbon dioxide from the air and forming the carbonate, having a strongly alkaline reaction, saline taste, and a faint but characteristic odour. Melting-point, 110° (after drying over quicklime). It is apparently volatile at ordinary temperatures, since it forms a cloud on being brought near the vapour of hydrochloric acid. It boils at 145° without decomposition. It should be free from chlorides and sulphates, and should sublime without leaving any residue. Piperazidine is a strong base, forming crystalline salts with acids; it also forms a hydrate (6H2O), which melts at 44°. It is unaffected by solution of chromic acid, or fuming nitric acid even if heated to 110°, but potassium permanganate gradually oxidises it in the cold. Its aqueous solution yields with solution of mercuric chloride a white precipitate; with Nessler's solution a white precipitate, not reddish (absence of ammonia); with cupric sulphate a light blue precipitate, which does not, however, dissolve in excess of piperazidine. Tannic acid gives a greyish precipitate, easily soluble in hot water; picric acid precipitates it in the form of lemon-yellow needles, soluble in hot water; the hydrochloric acid solution yields with platinum chloride a yellow precipitate which dissolves with difficulty in water and in alcohol; gold chloride, in not too dilute solution, gives a bright yellow precipitate of a well-crystallised double salt, easily soluble in hot water; with solution of bismuth potassium iodide, it gives a brick-red precipitate.
Readily soluble in water, somewhat less so in alcohol; its aqueous solution readily decomposes.
Action and Uses.—Piperazidine acts as a powerful solvent of uric acid in the test-tube, dissolving twelve times as much as lithium carbonate; on this account it is prescribed to prevent or remove the deposit of uric acid in the system by forming soluble urates, which would be eliminated in the urine. It is, however, extremely doubtful whether any such solvent action is exerted in the body; the amount of piperazidine appearing in the urine is very small, and it is found to be in combination with the stronger acids, and not with uric acid. A 0.2 per cent. solution of piperazidine in blood scrum has no solvent effect on sodium biurate, and this strength is not likely to be exceeded or attained in the living body. Piperazidine is conveniently administered as Granulae Piperazidinae, or it may be given dissolved in aerated water, or in mixture form. It has been given hypodermically in doses of 5 to 10 centigrams (¾ to 1 ½ grains). For use in painful gout and rheumatism, it is frequently prescribed with phenocoll hydrochloride or salicylate, with which, however, it is incompatible. In vesical irritation, a 1 per cent. solution is sued to wash out the bladder. Dimethyl-piperazidine tartrate (Lycetol) and ethylene-ethenyl-diamine (Lysidine) are substances resembling piperazidine in their properties. The former is a white powder, readily soluble in water; dose, ½ to 2 grammes (8 to 30 grains). Ethylene-ethenyl-diamine or methyl-gloxalidine is supplied in 50 per cent. solution, the liquid being given in doses of ½ to 2 mils (8 to 30 minims); an acid tartrate (Lysidine Bitartrate) is a white, crystalline powder, readily soluble in water, and given in doses of 1 to 2 grammes (15 to 30 grains). Piperazidine quinate (Sidonal) is similarly employed; it is a white powder, soluble in water, and is given in doses of 5 to 10 decigrams (5 to 25 grains). It must be distinguished from New Sidonal, a gout remedy, which has been stated to consist of quinic anhydride or quinic acid lactone mixed with one-third its weight of quinic acid; it is soluble in water and in alcohol, and is given in similar doses to piperazidine quinate. Piperazidine is incompatible with acetanilide, alkaloidal salts, spirit of nitrous ether, sodium salicylate, and salts of iron and mercury.
Dose.—3 to 10 decigrams (5 to 15 grains).
- Granulae Piperazidinae, B.P.C.—GRANULAR EFFERVESCENT PIPERAZIDINE. 8 in 100.
- Dose.—4 to 12 grammes (60 to 180 grains).