DlC'TK)NAl:V 01- THE ACTIVK I'lilNCIl'LliS 01' I'L.VNTS. 



15 



Disagreeable metallic bitter taste. Produces dilatation of the pupil. De- 

 composed readily by strong acids and alkalies (e.\cept ammonia), forming 

 tropine and tropic acid, C,|Hj„Oj. 



Soluble in UdO parts cold, or [>8 of boiling water, 3 chloroform, 30 cold 

 and G boiling ether, 40 benzene ; miscible in nearly all proportions with 

 alcohol ; sdluble also in glycerine, but scarcely in petroleum ether or 

 carbon bisulphide. It is removed by benzene from alkaline solulion, not 

 easily by ether. 



Precipitants : 



Alkaline hydrates (not if 

 dilute), pp. sol. in excess with 

 gradual decomposition. 



Alkaline carbonates. 



\Not bicarbonates.] 



[Xol sodium acetate, compare 

 Opium.] 



Ammonia hydrate. 



\_Not am. carbonate.] 



Tannic acid (1 in 3,000 ? sol. in 

 HCl. not 1 in 200.— Dragen- 

 dorff.* ' No pp. unless acid.' 

 — Dupuy.) 



? Picric acid, 1 in 200, not 1 in 

 50i> ; [ip. sol. excess, or pp. 

 with Daturine, not with 

 Atropine ? 



[Not ferric chloi'ide.] 



? Platinum chloride, no pp. 

 Atropine, pp. Daturine — 

 (Erhardt). 



Gold chloride, lemon-coloured 

 pp. 1 iu 3.01)0? (1 in 100, 

 Dragendorff).* No reduc- 

 tion. 



Mercuric-potassic iodide, up to 

 1 in 7,000. 



Mercuric chloride, cloud at 1 in 

 3,000 then pp, ; partly sol. 

 HCl. 

 * ' Ermitteluiig tier Glf te. ' 



""'Mercuric chloride in alcohol, 



to ihe free base, red pp. 



(HgO). 

 [Nol by potassium ferrocyanide. 



,, ,, feri'icyanide. 



„ „ sulphocyanide. 



Not by potassium chromate.] 

 Potassium bichromate, 1 in 3,000 



gradually. 

 [Not chromic acid, 5 per cent. 



solulion.] 

 [Not silver-potassic cyanide.] 

 Phospho-molybdic acid, yellow 



flocks-v>.blue with ammonia ; 



cloud 1 in 4,000. 

 Phospho-tungstic acid. 

 Phospho antimonic acid, up to 1 



in 6,000, sol. warm, 

 lodo - potassic iodide, reddish- 

 brown, 1 in 3,000. 

 [Not potassic iodide.] 

 Bismuth-potassic iodide, orange; 



flocculent pp. 1 in 10,000 ; faint 



at 1 in 1G,000. 

 Cadmium-]iotassic iodide (1 in 



500— Drageudorff).t 

 [Not zinc-potassic iodide, or but 



slightly.] 

 Mercurods nitrate, dilute solution 



free from excess of acid, gives, 

 * Gerraril test (see'Part III. ). 



compound with Atropine or 

 Hyoscyamine, seen as ladiat- 

 ing leaflets under the micro- 

 scope (■ Characteristic' — T. G. 

 Wormly). 

 Charcoal, partially absorbs. 



when added to a dilute solu- 

 tion of free -4.tropine, a black 

 pp. 

 Bromine water, j'ellow, becoming 



crystalline. 

 Bromine in hydrobromic acid or 



in alcohol, gives crystalline ' 



Colour tests (nearly all are negative ; see, however, V'itali test) : 



Concentrated sulphuric acid, colourless. If atropine sulphate be 



heated first alone till white fumes appear, then sulphuric acid (I',') 



gramme) be added, and farther heated till browned, an agreeable 



odour is produced on subsequent addition of 2 cc. water. On then 



adding potassium permanganate (a fragment), an odour of bitter 



almond oil will be perceived. 



Concentrated sulphuric acid and potassium bichromate, discoloured 



merely. 

 Concentrated nitric acid, crystals become brown ; solution colourless. 

 "Vitali test : Evaporated with nitric acid at 100°, then touched with 

 a drop of freshly-prepared alcoholic potash, magnificent violet 

 changing to cherry red gradually. 

 Concentrated hydrochloric acid, no effect. 

 Periodic acid, not reduced. 

 Frcihde's solution, colourless. 



These have been formed artificially from the 



respective optically active tropic acids with 



(li) DEXTRO-ATROPINE I Trojune ; they form crystals from alcohol, 



(-■) L/EVO-ATROPIHE I the former melting at 110° 111°, and the 



latter at 111°. Rotatory ])Ower of former 



I =-hl0°. 



(d) TROPINE A., C„H,5N0 or C5H-(CfT.,CFI,,0H)NCH, (compare 

 Ecgonine, under Cora). Formed from Atropine or Hyoscyamine by acids 

 or alkalies ; rhombic leaflets ; M.P. (!1°, boils at 229° ; hygroscopic. 



Soluble in water and alcohol readily. Platinum salt soluble. 

 Concentrated sulphuric acid yields («■). 



(e) TROPIDINE A. (from above), CgHuN. 

 like odour ; boils at 1(')2°. 



Soluble in cold water ; less easily hot. 



Picric acid gives yellow pp. 



C/) HOM ATROPINE A., CsH^iNOj (from Tropine and oxytoluic acid). 



An oily liquid with con line- 



