The alkaloids of Picralima klaineana / by T.A. Henry and T.M. Sharp.

  • Henry, Thomas Anderson, 1873-1958
Date:
[1927.]
Catalogue details

Licence: Public Domain Mark

Credit: The alkaloids of Picralima klaineana / by T.A. Henry and T.M. Sharp. Source: Wellcome Collection.

    8/16 (page 1955)
    hydrobromide in appearance, but is of paler colour and rather more soluble in water or alcohol. It has m. p. 227° and [a]ff —26*6° (in water; c = 0*8769) or —32*8° (in alcohol; c = 1*716) and crystallises with one molecule of water (Found : loss in a vacuum at 120°, 4*0. C22H2804N2,HC1,H20 requires H20, 4*1%. Found for dry salt: C, 62*5, 62*6 ; H, 6*9, 6*7 ; N, 7*1; Cl, 8*5, 8*4. C22H2804N2,HC1 requires C, 62*7; H, 7*0; N, 6*6; Cl, 8*4%). The sulphate, prepared as described above, crystallises from hot water or hot alcohol in rosettes of flattened needles, which rapidly become red on exposure to light. It melts at 221° and has [a]}?’ —40*3° (in water; c = 2*0868). The salt is abnormal in composition, crystallises with 10 molecules of water of crystallisation, of which 9 are lost at atmospheric temperature in a vacuous desiccator over calcium chloride. Loss (a) from air-dry salt at 100° in a vacuum, 11*5; (6) from salt previously dried to constant weight in a vacuous desiccator, 1*8. (C22H2804N2)3,2H2S04, for 10H2O, requires H20 11*8%, and for 1H20 1*3% [Found for dry salt: C, 58*8; H, 6*7; S, 4*45. (C22H2804N2)3,2H2S04 requires C, 58*7 ; H, 6*5; S, 4*7%]. This may be a double compound consisting of one molecule of the acid salt with one molecule of the normal salt (B,H2S04; B2,H2S04). In this connexion, it may be noted that another dibasic acid, viz., oxalic acid, yields at least three salts, which, however, have not been satisfactorily separated. The hydriodide is precipitated as a crystalline powder on adding potassium iodide to even a dilute solution in water of any soluble salt of akuammine. It cannot be crystallised from hot water without decomposition, but separates from hot alcohol in anhydrous, minute, pale grey needles, m. p. 226° (Found : C, 52*0; H, 6*0. C22H2804N2,HI requires C, 51*5; H, 5*7%). The nitrate, also prepared by precipitation, crystallises from boiling alcohol in pale cream-coloured needles, m. p. 224°. The thiocyanate, similarly prepared, crystallises from alcohol in pale greyish needles, m. p. 218°. The perchlorate, precipitated by addition of sodium perchlorate to a solution of the hydrochloride in water, crystallises from hot alcohol in colourless, spheroidal granules, m. p. 215°, if the solution is concentrated, and from more dilute solutions in colourless needles also melting at 215°. This salt becomes pink on exposure to air and resinous after several crystallis¬ ations from boiling alcohol. The pier ate crystallises from hot alcohol in rosettes of brilliant yellow needles, m. p. 199°. The picrolonate, precipitated in minute, yellow needles, darkens at 160° and froths at 194°. On dissolution in hot alcohol it deposits a deep blue dye. No chloroaurate has been prepared, as akuammine hydrochloride